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Combined circulating epigenetic markers to improve mesothelin performance in the diagnosis of malignant mesothelioma
... In MM, several studies investigated miRNA expression in tumor tissue, blood cells, plasma or serum, pleural effusions or cell lines, and a number of miRNAs were implicated in MM pathogenesis and diagnosis (reviewed in [3,29,30]). Among them, miR-103-3p, miR-126-3p, and miR-625-3p were identified as suitable biomarkers in multiple studies [30][31][32][33][34][35][36][37][38][39][40][41][42]. In MM patients, miR-103-3p and miR-126 were downregulated compared to asbestos-exposed or healthy controls [30][31][32][33][34][35][36][37][38][39][40][41], while miR-625-3p was upregulated [30,42]. ...
... Among them, miR-103-3p, miR-126-3p, and miR-625-3p were identified as suitable biomarkers in multiple studies [30][31][32][33][34][35][36][37][38][39][40][41][42]. In MM patients, miR-103-3p and miR-126 were downregulated compared to asbestos-exposed or healthy controls [30][31][32][33][34][35][36][37][38][39][40][41], while miR-625-3p was upregulated [30,42]. Some of the studies also suggested that a combination of a few miRNAs or their combination with mesothelin could serve as a better diagnostic biomarker [32,34,39,40]. ...
... In MM patients, miR-103-3p and miR-126 were downregulated compared to asbestos-exposed or healthy controls [30][31][32][33][34][35][36][37][38][39][40][41], while miR-625-3p was upregulated [30,42]. Some of the studies also suggested that a combination of a few miRNAs or their combination with mesothelin could serve as a better diagnostic biomarker [32,34,39,40]. On the other hand, the role of miRNAs in MM prognosis is not well established. ...
Malignant mesothelioma (MM) is characterized by poor prognosis and short survival. Extracellular vesicles (EVs) are membrane-bound particles released from cells into various body fluids, and their molecular composition reflects the characteristics of the origin cell. Blood EVs or their miRNA cargo might serve as new minimally invasive biomarkers that would enable earlier detection of MM or treatment outcome prediction. Our aim was to evaluate miRNAs enriched in serum EVs as potential prognostic biomarkers in MM patients in a pilot longitudinal study. EVs were isolated from serum samples obtained before and after treatment using ultracentrifugation on 20% sucrose cushion. Serum EV-enriched miR-103-3p, miR-126-3p and miR-625-3p were quantified using qPCR. After treatment, expression of miR-625-3p and miR-126-3p significantly increased in MM patients with poor treatment outcome (p = 0.012 and p = 0.036, respectively). A relative increase in miR-625-3p expression after treatment for more than 3.2% was associated with shorter progression-free survival (7.5 vs 19.4 months, HR = 3.92, 95% CI = 1.20–12.80, p = 0.024) and overall survival (12.5 vs. 49.1 months, HR = 5.45, 95% CI = 1.06–28.11, p = 0.043) of MM patients. Bioinformatic analysis showed enrichment of 33 miR-625-3p targets in eight biological pathways. Serum EV-enriched miR-625-3p could therefore serve as a prognostic biomarker in MM and could contribute to a more personalized treatment.
... Szlosarek et al. 58 1 59 1 60 1 61 1 62 1 63 1 64 1 15 1 65 1 16 1 67 1 69 1 ...
... 35 Several studies compare mesothelioma samples with nontumor samples and most perform a statistical analysis. The following genes, for which only one study compared methylation between mesothelioma and nontumor samples (and are therefore not included in the meta-analysis), revealed a significant difference in methylation: hypermethylated were CDX2 (p ¼ 0.0091), 17 miR-145 (p < 0.01), 8 SLC6A20 (p ¼ 0.0022), 17 and TM (p ¼ 0.0005), 60 whereas hypomethylated were ATM (p ¼ 0.0001), 17 CDKN2B (p < 0.0001), 17 HOXA1 (p ¼ 0.0033), 17 LZTS1 (p ¼ 0.0098), 17 and SYK (p ¼ 0.0003). 17 Tsou et al. 17 reported the percentages of methylationpositive samples but did the statistical comparison with median percentage of methylated reference calculated from the positive methylation values as they used the MethyLight technique, which gives an exact methylation 29 and SHOX2 (72% of 87 MM tissue samples). ...
... 56 Although serum SMRP has a high specificity as diagnostic biomarker, the sensitivity is low, which can possibly be explained by the fact that methylation is retained or regained in a subset of tumors. 56,60 In two studies, a genome-wide methylation analysis was executed; these studies are not included in Table 2. 30,35 Christensen et al. 30 investigated the methylation level of 1505 CpG sites associated with 803 cancerrelated genes using the Illumina GoldenGate methylation bead array. They compared 158 MPM samples with 18 normal pleura samples and identified 969 CpG sites that are aberrantly methylated in mesothelioma samples. ...
Background
Malignant mesothelioma is an aggressive cancer type linked to asbestos exposure. Due to several intrinsic challenges, mesothelioma is often diagnosed in an advanced disease stage. Therefore, there is need for diagnostic biomarkers that may contribute to early detection. Recently, the epigenome of tumours is extensively being investigated to identify biomarkers. This manuscript is a systematic review summarizing the state-of-the-art research investigating DNA methylation in mesothelioma.
Methods
Four literature databases (Pubmed, Scopus, Web of Science, Medline) were systematically searched for studies investigating DNA methylation in mesothelioma up to October 16, 2020. A meta-analysis was performed per gene investigated in at least two independent studies.
Results
Fifty-three studies investigated DNA methylation of 97 genes in mesothelioma and are described in a qualitative overview. Ten studies investigating 13 genes (APC, CDH1, CDKN2A, DAPK, ESR1, MGMT, miR-34b/c, PGR, RARβ, RASSF1, SFRP1, SFRP4, WIF1) were included in the quantitative meta-analysis. In this meta-analysis, the APC gene is significantly hypomethylated in mesothelioma, while CDH1, ESR1, miR-34b/c, PGR, RARβ, SFRP1 and WIF1 are significantly hypermethylated in mesothelioma. The three genes that are the most appropriate candidate biomarkers from this meta-analysis are APC, miR-34b/c and WIF1. However, both study number and study objects comprised in this meta-analysis are too low to draw final conclusions about their clinical applications.
Conclusion
The elucidation of the genome-wide DNA methylation profile of mesothelioma is desirable in the future, using a standardized genome-wide methylation analysis approach. The most informative CpG sites from this signature could then form the basis of a panel of highly sensitive and specific biomarkers that can be used for the diagnosis of mesothelioma and even for the screening of an at high-risk population of asbestos-exposed individuals.
... After an abstract and full-text screening, four studies were included in this systematic review and meta-analysis (20)(21)(22)(23). The characteristics of these included studies are summarized in Table 1. ...
... The characteristics of these included studies are summarized in Table 1. Three studies were from Italy (20)(21)(22), and one was from Germany (23). The sample size ranged from 66 to 240, and the total sample size of this meta-analysis was 615, with 156 of them being MPM. ...
... The type of data collection (prospective, retrospective) was also not reported in all studies. Two studies used U6 as the internal control in detecting circulating miR-126 with PCR (20,23), while the remaining two studies used cel-miR-39 (21,22). The biopsy was used as a gold standard in three studies (20)(21)(22), while one study did not report the gold standard for MPM diagnosis. ...
Background:
Circulating microRNAs are novel diagnostic markers for various types of cancer. Several studies have investigated the diagnostic accuracy of circulating miR-126 for malignant pleural mesothelioma (MPM), but the results varied. Therefore, we performed a systematic review and meta-analysis to investigate the diagnostic value of circulating miR-126 for MPM.
Methods:
The PubMed database was searched to identify potentially eligible studies published before October 2020. The studies investigating the diagnostic value of circulating miR-126 for MPM were included in a systematic review and meta-analysis. A bivariate model was used to pool eligible studies' sensitivity and specificity. The revised tool for the quality assessment of diagnostic accuracy studies (QUADAS-2) was used to assess eligible studies' quality.
Results:
Four studies with 156 MPM patients and 459 controls were included in this systematic review and meta-analysis. The pooled diagnostic sensitivity and specificity of circulating miR-126 for MPM were 0.71 and 0.69, respectively. A high risk of bias was observed in the domains of patient selection, index test, and flow and timing.
Conclusions:
Circulating miR-126 has limited value for diagnosing MPM. Considering that the available studies have a high risk of bias, further rigorous studies are needed to assess the diagnostic value of circulating miR-126 for MPM.
... Several reports have indicated that miR-126 expression was downregulated in cancer tissues compared with non-tumor tissues (67), including MM (80)(81)(82)(83)(84)(85)(86), and its restoration impaired cell growth, migration, invasive properties, and tumorigenesis (87)(88)(89)(90)(91). Promoter methylation resulted in the silencing of miR-126 in colorectal cancer (92,93), breast cancer (94), lung cancer (95,96), esophageal squamous cell carcinoma (97), glioma (98), and MM (66). Hypermethylation of the CGI in EGFL7 intron 2, which harbors the S2 transcriptional initiation site of EGFL7 mRNA and miR-126, was found in MM and was found to be a significant prognostic factor associated with poor survival (66). ...
... subjects with high risk, suggesting that they have a potential role as predictive biomarkers. Indeed, the combination of two circulating epigenetic biomarkers (methylated thrombomodulin and epi-miR-126) with SMRPs for early MM diagnosis overcomes the limitations of using SMRPs alone (83). SMRPs are widely studied tumor markers for the early diagnosis of MM or for monitoring the response to treatment (130). ...
... SMRPs are widely studied tumor markers for the early diagnosis of MM or for monitoring the response to treatment (130). The level of SMRPs can differentiate MM patients from healthy controls with a sensitivity of 60-70% and specificity of 90-100%, and it can better discriminate controls from patients with advanced MM (83,131). However, this correlation was found only in the 40-50% of epithelioid or biphasic MM histotypes and in the 30% of sarcomatoid MM. ...
Asbestos exposure leads to epigenetic and epigenomic modifications that, in association with ROS-induced DNA damage, contribute to cancer onset. Few miRNAs epigenetically regulated in MM have been described in literature; miR-126, however, is one of them, and its expression is regulated by epigenetic mechanisms. Asbestos exposure induces early changes in the miRNAs, which are reversibly expressed as protective species, and their inability to reverse reflects the inability of the cells to restore the physiological miRNA levels despite the cessation of carcinogen exposure. Changes in miRNA expression, which results from genetic/epigenetic changes during tumor formation and evolution, can be detected in fluids and used as cancer biomarkers. This article has reviewed the epigenetic mechanisms involved in miRNA expression in MM, focusing on their role as biomarkers of early diagnosis and therapeutic effects.
... In a new contribution, Santarelli et al. [85] analyzed the diagnostic value of a combination of three markers (miR-126, methylated thrombomodulin promoter or Met-TM and SMRPs) in serum samples of 45 MPM patients, 99 asbestos-exposed subjects and 44 healthy controls to detect MPM. They further evaluated the three biomarkers in 18 MPM, 50 asbestos-exposed subjects, 20 healthy controls and 42 lung cancer (LC) patients. ...
... On the other hand, some relevant information was missing, such as the histological subtypes of MPM patients and how the healthy status of the controls was verified. This study did not find the down-regulation of miR-126 in MPM as previously reported by Santarelli et al. [29,85], who also used serum from asbestos-exposed subjects as comparative controls. ...
... (b) MPM vs. Healthy controls. (c) MPM vs. asbestos-exposed controls vs. healthy controls [29,73,85] Only validated miRNAs (RT-qPCR) are included in this list. ↑ = upregulated expression; ↓ = downregulated expression. ...
Malignant pleural mesothelioma (MPM) is a rare but aggressive tumor that originates in the pleura, is diagnosed in advanced stages and has a poor prognosis. Accurate diagnosis of MPM is often difficult and complex, and the gold standard diagnosis test is based on qualitative analysis of markers in pleural tissue by immunohistochemical staining. Therefore, it is necessary to develop quantitative and non-subjective alternative diagnostic tools. MicroRNAs are non-coding RNAs that regulate essential cellular mechanisms at the post-transcriptional level. Recent evidence indicates that miRNA expression in tissue and body fluids is aberrant in various tumors, revealing miRNAs as promising diagnostic biomarkers. This review summarizes evidence regarding secreted and tissue miRNAs as biomarkers of MPM and the biological characteristics associated with their potential diagnostic value. In addition to studies regarding miRNAs with potential diagnostic value for MPM, studies that aimed to identify the miRNAs involved in molecular mechanisms associated with MPM development are described with an emphasis on relevant aspects of the experimental designs that may influence the accuracy, consistency and real diagnostic value of currently reported data.
... Given that methylation of the TM promoter is responsible for silencing TM expression in MM tissue, aberrantly methylated TM DNA sequences were detected in the circulation of MM patients. High level of methylated DNA TM was found in serum of MM patients, and its level was affected by neither tumour resection nor tumour histotype [73]. ...
... Downregulation of miR-126 may represent a marker for early detection of cancer. The ROC analysis revealed that miR-126 itself can predict the presence of MM with good sensitivity (75%) but poor specificity (54%), and appears to reflect the prognosis [40,73]. To improve its specificity, miR-126 serum levels were combined with those of serum mesothelin-related peptides (SMRPs), the most studied and frequently used biomarker of MM, and proposed as a combined marker for early detection of MM [40]. ...
... To improve its specificity, miR-126 serum levels were combined with those of serum mesothelin-related peptides (SMRPs), the most studied and frequently used biomarker of MM, and proposed as a combined marker for early detection of MM [40]. SMRP levels differentiate MM patients from healthy controls with the sensitivity of 60-70% and specificity of 90-100%, and better discriminate controls from patients with advanced epithelioid or biphasic MM than those with sarcomatoid or early-stage MM [81,73]. However, a meta-analysis study revealed that, in symptomatic or high-risk subjects, a negative blood test for SMRPs did not exclude MM even at a high sensitivity threshold (1-1.5 nmol/l) [81]. ...
Lung cancer (LC) and malignant mesothelioma (MM) are malignancies linked to environmental/occupational exposure, which are increasing in incidence. Despite advances in chemotherapy, radiation therapy and surgical management of LC and MM, the median survival remains less than 12 months. Early detection represents one of the most promising approaches to reducing the growing cancer burden by increasing chemotherapy treatment efficiency. At present, early diagnosis is rather difficult and depends on invasive sampling of pleural fluid or tissue. Currently the most widely used screening method for the surveillance of exposed subjects is computed tomography (CT), which is costly, exposes patients to repeated high doses of radiation, and typically detects the malignancy at its advanced stage. Recently, a virtually non-invasive ‘liquid biopsy’ has emerged as source to characterize tumour heterogeneity. The genetic/epigenetic changes during tumour evolution can be detected in fluids and used as cancer biomarkers. Therefore, increasingly interest has been paid to circulating (cell-free) nucleic acids (cfDNA/cfmiRNAs) epigenetically modulated during cell transformation. Hypermethylation of tumour suppressor genes is frequently observed in cancers, and such epigenetic changes are potential markers for detecting and monitoring tumours. The same predictive biomarkers can be used as therapy targets.
... Currently, diagnosis of MPM is based on histopathology and immunohistochemistry (IHC), despite the low sensitivity of these methods [3,4]. Therefore, it has been proposed that certain combinations of non-invasive biomarkers might improve MPM diagnosis [6][7][8][9]. Among those, mesothelin and calretinin showed promising results [6]. ...
... Several studies in different populations have analyzed the combination of certain biomarkers at different molecular levels to improve MPM diagnosis [6][7][8]20,25,29]. In this regard, our study aimed to assess miR-103a-3p in leukocytes in addition to mesothelin and calretinin in plasma. ...
Malignant pleural mesothelioma (MPM) is a cancer associated with asbestos exposure and its diagnosis is challenging due to the moderate sensitivities of the available methods. In this regard, miR-103a-3p was considered to increase the sensitivity of established biomarkers to detect MPM. Its behavior and diagnostic value in the Mexican population has not been previously evaluated. In 108 confirmed MPM cases and 218 controls, almost all formerly exposed to asbestos, we quantified miR-103-3a-3p levels in leukocytes using quantitative Real-Time PCR, together with mesothelin and calretinin measured in plasma by ELISA. Sensitivity and specificity of miR-103-3a-3p alone and in combination with mesothelin and calretinin were determined. Bivariate analysis was performed using Mann-Whitney U test and Spearman correlation. Non-conditional logistic regression models were used to calculate the area under curve (AUC), sensitivity, and specificity for the combination of biomarkers. Mesothelin and calretinin levels were higher among cases, remaining as well among males and participants ≤60 years old (only mesothelin). Significant differences for miR-103a-3p were observed between male cases and controls, whereas significant differences between cases and controls for mesothelin and calretinin were observed in men and women. At 95.5% specificity the individual sensitivity of miR-103a-3p was 4.4% in men, whereas the sensitivity of mesothelin and calretinin was 72.2% and 80.9%, respectively. Positive correlations for miR-103a-3p were observed with age, environmental asbestos exposure, years with diabetes mellitus, and glucose levels, while negative correlations were observed with years of occupational asbestos exposure, creatinine, erythrocytes, direct bilirubin, and leukocytes. The addition of miR-103a-3p to mesothelin and calretinin did not increase the diagnostic performance for MPM diagnosis. However, miR-103a-3p levels were correlated with several characteristics in the Mexican population.
... Other than longer RNA species, microRNAs show remarkable stability in the blood of patients due to the fact that they are mainly bound to lipoproteins or encapsulated into extracellular vesicles. With this in mind, a small number of studies has been published proposing for example low levels of miR-103 in whole blood (192,193), low levels of miR-126 (181,188,194) in serum, low level of miR-132 in plasma (195) or high levels of miR-625-3p (196) in plasma or serum to be associated with the presence of MPM, and allowed to discriminate those patients from healthy controls and asbestos-exposed individuals. While these studies again provide first evidence of the biomarker potential of microRNAs in the circulation, large independent validation studies undertaken by independent research groups are usually missing, and none of the candidates is yet ready for routine clinical application. ...
... However, it has a low sensitivity to be considered as a good marker for MPM (204). This led Santarelli et al. to identify a new marker for asbestos-exposed mesotheliomas (194). Thrombomodulin (TM) expression is silenced in malignant mesothelioma through a mechanism that involved the methylation of TM promoter by the recruitment of PARP1. ...
Malignant pleural mesothelioma (MPM) is a rare and fatal disease of the pleural lining. Up to 80% of the MPM cases are linked to asbestos exposure. Even though its use has been banned in the industrialized countries, the cases continue to increase. MPM is a lethal cancer, with very little survival improvements in the last years, mirroring very limited therapeutic advances. Platinum-based chemotherapy in combination with pemetrexed and surgery are the standard of care, but prognosis is still unacceptably poor with median overall survival of approximately 12 months. The genomic landscape of MPM has been widely characterized showing a low mutational burden and the impairment of tumor suppressor genes. Among them, BAP1 and BLM are present as a germline inactivation in a small subset of patients and increases predisposition to tumorigenesis. Other studies have demonstrated a high frequency of mutations in DNA repair genes. Many therapy approaches targeting these alterations have emerged and are under evaluation in the clinic. High-throughput technologies have allowed the detection of more complex molecular events, like chromotripsis and revealed different transcriptional programs for each histological subtype. Transcriptional analysis has also paved the way to the study of tumor-infiltrating cells, thus shedding lights on the crosstalk between tumor cells and the microenvironment. The tumor microenvironment of MPM is indeed crucial for the pathogenesis and outcome of this disease; it is characterized by an inflammatory response to asbestos exposure, involving a variety of chemokines and suppressive immune cells such as M2-like macrophages and regulatory T cells. Another important feature of MPM is the dysregulation of microRNA expression, being frequently linked to cancer development and drug resistance. This review will give a detailed overview of all the above mentioned features of MPM in order to improve the understanding of this disease and the development of new therapeutic strategies.
... In another contribution the same group demonstrated that a "3-biomarker classifier", based on serum levels of SMRP, miR-126 and methylated thrombomodulin promoter (Met-TM), improved the differential diagnosis of MPM from asbestos-exposed subjects and healthy controls, when compared to SMRP alone [78]. ...
... In fact, it has been reported that, in MPM tissue, TM gene expression can be silenced through epigenetic mechanisms and, similarly, hypermethylation of miR-126 promoter region is responsible for its downregulation [101]. Despite the poor sensitivity (60%), the authors reported that circulating methylated TM DNA significantly discriminated MPM patients from controls with high specificity (82%), thus complementing the performance of miR-126 and SMRP alone for MPM detection [78] (Table 3). ...
Malignant pleural mesothelioma (MPM) is an aggressive tumor strictly connected to asbestos exposure. Prognosis is dismal as diagnosis commonly occurs in advanced stage. Radiological screenings have not proven to be effective and also pathological diagnosis may be challenging. In the era of precision oncology, validation of robust non-invasive biomarkers for screening of asbestos-exposed individuals, assessment of prognosis and prediction of response to treatments remains an important unmet clinical need. This review provides an overview on current understanding and possible applications of liquid biopsy in MPM, mostly focused on the utility as diagnostic and prognostic test.
... The AUC in one study was as high as 0.95, 34 but in another study, the AUC was only 0.71. 35 Notably, in a head-to-head comparison study, the AUC of miR-126 was lower than SMRP (0.71 vs. 0.72), indicating that the diagnostic accuracy of miR-126 was inferior to that of SMRP. However, the combination of miR-126 and SMRP can improve diagnostic accuracy. ...
... However, the combination of miR-126 and SMRP can improve diagnostic accuracy. 35 Exosomes are a subtype of extracellular vesicles with a diameter between 30 and 100 nm, containing miRNA, mRNA, protein, and DNA, protected by a lipid bilayer. Cancer cells can secrete exosomes into the circulation and the signature of proteins and nucleic acids contained in exosomes are significantly correlated with those in primary tumor cells. ...
Malignant pleural mesothelioma (MPM) is a type of cancer originating from the pleura with high aggressiveness and poor prognosis. A timely diagnosis is crucial to improve its prognosis. Laboratory biomarkers have significant advantages of reduced invasiveness, low cost, and are observer-independent, and therefore represent a promising diagnostic tool for MPM. MicroRNA is a family of non-coding RNA that regulates gene expression at the post-transcriptional level. Accumulated studies showed that microRNA, either in tissue, circulating, and body fluid, has potential diagnostic value for various disorders. Here, we reviewed the diagnostic value of microRNA for MPM.
... Santarelli et al. (87) evaluated alterations in the methylation of the thrombomodulin (TM) gene in serum in association with serum levels of SMRP and miR-126 in MPM patients (N = 45), asbestos-exposed healthy subjects (N = 99), and healthy donors (N = 44). The model based on the combination of these 3 parameters improved the differential diagnosis of MPM, with an AUC of 0.857. ...
... A significant risk of disease (odds ratio >4) was found in the presence of high levels of SMRP in association with altered levels of either miR-126 or TM promoter methylation, and when both miR-126 and TM promoter methylation were altered even at low SMRP concentration. It will be interesting to test the validity of these findings in large prospective longitudinal cohorts (87,109). ...
Malignant pleural mesothelioma (MPM) is an aggressive tumor linked to asbestos exposure. Although the risk factors for MPM are well-known, the majority of MPM patients are diagnosed at an advanced stage and have a very poor prognosis. Circulating biomarkers for early diagnosis remain to be identified, and the current standard for MPM diagnosis relies on pleural biopsies. Robust non-invasive tests for the screening of asbestos-exposed subjects are therefore an important unmet clinical need. This review provides a critical summary of recent liquid biopsy-based studies aimed at discovering novel blood-based circulating biomarkers for the early diagnosis and prognostic stratification of MPM patients.
... This outcome would endorse our previous results regarding the use of Fb-3 as a possible screening biomarker for FE exposed individuals, thereby contributing to the monitoring of the population at risk. This would support their previous results concerning the use of Fb-3 as a potential screening biomarker for FE-exposed people, thus causative to the monitoring of the people at risk [58][59][60][61][62][63][64][65][66][67][68][69]. ...
... Rapisarda et al. [56] theorized that Fb-3 might be accountable for the malignant transformation of mesothelial cells due to exposure to asbestiform fibers. They employed the previously homogeneous reproduction of the lung as of chronically FE exposed sheep grazing in Biancavilla area [63][64][65][66][67][68][69][70][71][72]. The results reported that Fb-3 was overexpressed in alveolar and bronchiolar epithelial cells and the pulmonary interstitium at rest if with dissimilar degrees of attention. ...
Many malignant diseases are associated with past asbestos exposure; the most lethal and strictly related to previous fiber exposure being malignant mesothelioma (MM). Effective preventive protocols may include sensitive and specific biomarkers. The role of Fb-3 has been recently investigated for MM early detection, but its role is still under debate. After an independent search for scientific literature, nine studies were included for a systematic review. Human Fb-3 levels seem to be able to separate healthy people with previous exposure to asbestiform fibers from MM patients. Fb-3 blood levels can distinguish MM effusions from other malignant and benign effusions. Furthers investigations on more significant groups of patients are desirable to validate and assess the validity of combining Fb-3 with other biomarkers.
... Several panels of biomarkers have been suggested as tools for screening and early diagnosis, clinical monitoring, prognosis and screening of MPM (60)(61)(62)(63)(64)(65)(66)(67)(68). The combinations studied are multiple: 80HdG, VEGFbeta and SMRPs (60), miR-126, in association with SMRPs (61), serum concentrations of SMRP, CA125, and CYFRA21-1 (62), combination of serum SMRP and pOPN (27), combination of SMRP and miR-103a-3p (63,64), SMRPs, miR-126 and methylated thrombomodulin promoter, Met-TM (65), fibulin-3 and SMRP (66), combination of miR-132-3 and miR-126 (48), combination of six biomarkers (SMRP-pOPN-IL6-vimentin-desmin-HGF) (56). ...
... Several panels of biomarkers have been suggested as tools for screening and early diagnosis, clinical monitoring, prognosis and screening of MPM (60)(61)(62)(63)(64)(65)(66)(67)(68). The combinations studied are multiple: 80HdG, VEGFbeta and SMRPs (60), miR-126, in association with SMRPs (61), serum concentrations of SMRP, CA125, and CYFRA21-1 (62), combination of serum SMRP and pOPN (27), combination of SMRP and miR-103a-3p (63,64), SMRPs, miR-126 and methylated thrombomodulin promoter, Met-TM (65), fibulin-3 and SMRP (66), combination of miR-132-3 and miR-126 (48), combination of six biomarkers (SMRP-pOPN-IL6-vimentin-desmin-HGF) (56). ...
In the last decade there is been much interest in noninvasive, economic and well-accepted diagnostic tests for screening of subjects exposed to asbestos, and in patients with malignant pleuric mesothelioma (MPM) for diagnosis or monitoring response to treatment. Several biomarkers have been suggested as tools for screening and early diagnosis of MPM. Currently, in patients with MPM, have been reported high levels of soluble mesothelin-related peptides (SMRP), plasmatic osteopontin (pOPN), vimentin, fibulin-3 and many others as promising marker for diagnosis, even their use in prevention monitoring is still discussed. In this type of disease, a key role could be played by miRNAs, which expression has been investigated in a large series of MPM to examine new pathways useful in diagnosis, prognosis and therapy. An altered expression of some proteins has been reported, useful as biomarkers, in comparative proteomic analysis of malignant pleural mesothelioma. New promising markers are nowadays under study and alone or better in combination, they'll be very helpful in diagnosing, monitoring mesothelioma patients or for screening of risk groups.
... Also cell-free, circulating miRNAs have been suggested as biomarkers for MM (99)(100)(101). A plasma miRNA profiling was performed by comparing samples from MM patients and those from healthy controls. Three prognostic miRNA (miR-29c*, miR-92a, and the newly identified miR-625-3p) were validated as promising diagnostic markers for MM (92). ...
... Novel, and potentially more sensitive and specific MM biomarkers were evaluated, including MPF(31), OPN (60,64,66), fibulin-3 (70,72,73), HMGB1 (82), with promising results. In addition, a variety of deregulated miRNAs [reviewed in (109)], including the miR-score signature with prognostic significance (98), as well as different approaches based on proteomics technology, have been proposed as suitable MM markers (100,109). It is conceivable that a combination of the most performing and valuable markers validated by the ongoing studies will allow more accurate MM diagnosis and earlier detection in the near future. ...
Malignant mesothelioma (MM) is an aggressive and lethal cancer, mostly related to inhalation of asbestos and erionite fibers. MM is associated with poor prognosis, because of its resistance to current therapies, even if higher survival occurs in patients diagnosed and treated when at stage I of the disease. However, these do not exceed 5% of the total number of cases, due to the inadequacy of the existing biomarkers for early and accurate diagnosis. Therefore, new effective biomarkers are needed for MM detection at earlier stages and to develop tailored therapies. Here we review the most promising biomarkers in MM to date: mesothelin, soluble mesothelin-related peptides (SMRPs), megakaryocyte potentiating factor (MPF), Osteopontin (OPN), Fibulin-3, high mobility group B1 (HMGB1), microRNAs (miRNAs), multiplex protein signatures. The validation of these biomarkers will allow their use, alone or in combination, for monitoring individuals from cohorts at risk of MM and attaining early detection of MM that is instrumental in improving patient survival.
... Surgical treatment of mesothelioma might lead to an alteration of biomarker levels as shown for mesothelin [57]. Regarding partial pleurectomy and therefore at least a substantial reduction in tumor burden, no influence of the miR-132-3p performance was observable between the study groups, also implicating that the biomarkers might be robust. ...
... Regarding partial pleurectomy and therefore at least a substantial reduction in tumor burden, no influence of the miR-132-3p performance was observable between the study groups, also implicating that the biomarkers might be robust. Comparable results were obtained for miR-126 showing that the marker level did not change after tumor reduction [57]. ...
The use of circulating microRNAs as biomarkers has opened new opportunities for diagnosis of cancer because microRNAs exhibit tumor-specific expression profiles. The aim of this study was the identification of circulating microRNAs in human plasma as potential biomarkers for the diagnosis of malignant mesothelioma. For discovery, TaqMan Low Density Array Human MicroRNA Cards were used to analyze 377 microRNAs in plasma samples from 21 mesothelioma patients and 21 asbestos-exposed controls. For verification, individual TaqMan microRNA assays were used for quantitative real-time PCR in plasma samples from 22 mesothelioma patients and 44 asbestos-exposed controls. The circulating miR-132-3p showed different expression levels between mesothelioma patients and asbestos-exposed controls. For discrimination, sensitivity of 86% and specificity of 61% were calculated. Circulating miR-132-3p in plasma was not affected by hemolysis and no impact of age or smoking status on miR-132-3p levels could be observed. For the combination of miR-132-3p with the previously described miR-126, sensitivity of 77% and specificity of 86% were calculated. The results of this study indicate that miR-132-3p might be a new promising diagnostic biomarker for malignant mesothelioma. It is indicated that the combination of miR-132-3p with other individual biomarkers improves the biomarker performance.
... Circulating miR-126 was identified as a cancer suppressor in lung cancer, malignant mesothelioma, and so on. [20,21] However, other study indicated that miR-126 in plasma functioned as an oncogene in hepatocellular carcinoma and its expression was upregulated. [22] Nowadays, there was still not a comprehensive conclusion for the diagnostic value of miR-126 in detecting cancers, because of different ethnicity, different cancer types, and small sample size. ...
... Thus, 6 high-quality literatures from independent research group met the eligibility criteria for this meta-analysis (Fig. 1). [20][21][22][27][28][29][30] 3.2. Study characteristics and quality assessment ...
Background:
Cancer has become a major public concern all over the world and early diagnosis of cancer is of great benefit for treatment and prognosis. Several studies have investigated the association between abnormal circulating microRNA-126 (miR-126) expression and the risk of various cancers, but the results are inconsistent. Therefore, this meta-analysis was carried out to assess the potential diagnostic value of miR-126 for cancer.
Methods:
Relevant studies were searched from PubMed, Embase, and Web of Science and we calculated the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the summary receiver operator characteristic curve (AUC) to assess the diagnostic value of miR-126 for cancer detection.
Results:
A total of 745 cancer patients and 749 controls from 11 studies of 7 papers were included in this meta-analysis. The summary estimates revealed that the pooled sensitivity was 68% (95% confidence interval [CI]: 60-75%), the specificity was 76% (95% CI: 65-85%), the PLR was 2.87 (95% CI: 1.96-4.21), the NLR was 0.42 (95% CI: 0.35-0.52), the DOR was 7 (95% CI: 4-11), and the AUC was 0.77 (95%CI: 0.73-0.80). Moreover, the sample type, cancer type, sample size, and quality score might be sources of heterogeneity.
Conclusion:
This systematic review and meta-analysis suggests that miR-126 has great potential to be a noninvasive biomarker in the diagnosis of cancer. However, more well-designed studies with larger sample size on the diagnostic value of miR-126 for cancer are needed in the future.
... Early symptoms of MPM are usually nonspecific and diagnosis may be delayed. There are a number of comprehensive studies in the literature investigating potential biomarkers for the early diagnosis of MPM and its differentiation from MPM and malignant pleural metastasis, benign pleural effusions and benign asbestos pleurisy in symptomatic patients exhibiting past exposure to asbestos [2,3]. Considering the fact that MPM is a highly malignant tumour, biomarkers that could help physicians diagnose these patients earlier and increase their life expectancy may be of importance. ...
... Mesothelin and SMRP, although secreted by mesothelial cells at lower levels from normal mesothelial cells, were shown to exhibit overexpression in MPM [2][3][4]. Recent studies indicated that SMRP has a higher specificity in the diagnosis of MPM when compared to mesothelin itself [37][38][39]. Portal et al. [7]. ...
Introduction:
The purpose of this study was to investigate the potential value of certain biomarkers in predicting the presence of malignant pleural mesothelioma (MPM) in individuals environmentally exposed to asbestos.
Methods:
This prospective study investigated three groups; a control group composed of 41 healthy subjects, an asbestos exposure group consisting of 48 individuals, and a MPM group consisting of 42 patients. Serum levels of soluble mesothelin-related peptide (SMRP), thioredoxin-1 (TRX), epidermal growth factor receptor (EGFR), fibulin-3, syndecan-1 (SDC-1), and mesothelin were determined.
Results:
Benign pleural plaques were present in 27 (58.3 %) of the individuals in the asbestos exposure group. The asbestos exposure group had significantly higher mean TRX, SMRP, and mesothelin levels compared to the control group (p = 0.023, p = 0.011, and p < 0.001, respectively). Compared to the asbestos exposure group, the MPM group had significantly higher mean EGFR, TRX, SMRP, and fibulin-3 levels (p = 0.041, p = 0.023, p = 0.002, and p = 0.001, respectively), and significantly lower mean SDC-1 levels (p = 0.002). Unlike the other biomarkers, SMRP and TRX levels increased in a graded fashion among the control, asbestos exposure, and MPM groups, respectively. Area under the curve values for SMRP and TRX were 0.86 and 0.72, respectively (95 % CI 0.79-0.92 and p < 0.001 for SMRP, and 95 % CI 0.62-0.81 and p < 0.001 for TRX). The cut-off value for SMRP was 0.62 nmol/l (sensitivity: 97.6 %, specificity: 68.9 %, positive predictive value (PPV): 56.2 %, and negative predictive value (NPV): 98.3 %) and for TRX was 156.67 ng/ml (sensitivity: 92.9 %, specificity: 77.6 %, PPV: 41.4 %, and NPV: 92.1 %). The combination of the biomarkers reached a sensitivity of 100 %, but had lower specificity (as high as 27.7 %).
Conclusions:
Serum biomarkers may be helpful for early diagnosis of MPM in asbestos-exposed cases. SMRP and TRX increased in a graded fashion from the controls to asbestos exposure and MPM groups. These two seem to be the most valuable biomarkers for the diagnosis of MPM, both individually and in combination.
... Since OS is associated by the histotype of MPM, the prognostic value of the biomarkers was evaluated in patients with the epithelioid MPM subtype, which represents majority of cases. As previously reported, miR-126 and Mesothelin were associated with OS in the univariate analysis [34]. ...
Objectives
Malignant pleural mesothelioma (MPM) is an aggressive disease with grim prognosis due to lack of effective treatment options. Disease prediction in association with early diagnosis may both contribute to improved MPM survival. Inflammation and autophagy are two processes associated with asbestos-induced transformation. We evaluated the level of two autophagic factors ATG5 and HMGB1, microRNAs (miRNAs) such as miR-126 and miR-222, and the specific biomarker of MPM, soluble mesothelin related proteins (Mesothelin) in asbestos-exposed individuals, MPM patients, and healthy subjects. The performance of these markers in detecting MPM was investigated in pre-diagnostic samples of asbestos-subjects who developed MPM during the follow-up and compared for the three groups.
Results
The ATG5 best distinguished the asbestos-exposed subjects with and without MPM, while miR-126 and Mesothelin were found as a significant prognostic biomarker for MPM. ATG5 has been identified as an asbestos-related biomarker that can help to detect MPM with high sensitivity and specificity in pre-diagnostic samples for up to two years before diagnosis. To utilize this approach practically, higher number of cases has to be tested in order to give the combination of the two markers sufficient statistical power. Performance of the biomarkers should be confirmed by testing their combination in an independent cohort with pre-diagnostic samples.
... Examining the EBC samples with the MiSeq ® platform, only 6/24 miRNA were expressed in all the 6 study participants while, with the HiSeq ® platform, these were 16/24. Several papers evaluated the miRNA expression in MM patients [33][34][35][36][37][38][39] and, overall, identified 42 mi-RNA which expression was altered. With the MiSeq ® platform, we detected 28/42 of those, 6 of which were expressed in all the participating subjects. ...
Introduction:
Exhaled breath condensate (EBC) sampling has been suggested as a less-invasive and cost-effective method to detect biological macromolecules, including miRNA. To explore the feasibility of its use as a biomarker of early effects of asbestos exposure, we conducted a preliminary test on male volunteers by comparing the miRNA profile in the EBC and the plasma using 2 different sequencing platforms.
Methods:
Six male volunteers, all retired and unexposed to dust or fumes, participated in the test. RNA was extracted from 200 μL EBC samples and same-size plasma samples. Sample aliquots were processed in 2 laboratories using 2 different sequencing platforms: a MiSeq Illumina® platform and a more performing HiSeq Illumina® platform.
Results:
The HiSeq3000® sequencing platform identified twice as many unique molecular indexes (UMI)-validated miRNA as the MiSeq® platform. The Spearman's correlation coefficient between EBC counts and plasma counts was significant in 5/6 subjects with either platform (MiSeq® = 0.128-0.508, P = .026-<.001; HiSeq® = 0.156-0.412, P = .001-<.001). The intraclass correlation coefficient confirmed the consistency of the miRNA profile over the 6 participants with both biospecimens. Exploring the agreement between the EBC and plasma samples with Bland-Altman plots showed that using the HiSeq3000® platform substantially improved the EBC miRNA detection rate.
Conclusion:
Our preliminary study confirms that, when using the HiSeq® sequencing platform, EBC sampling is a suitable, non-invasive method to detect the miRNA profile in healthy subjects.
... miRNA-126 is a well-studied circulating microRNA that can assist in the diagnosis of MPM (48,49). Unlike traditional tumor markers, circulating miR-126 level in MPM patients is reduced rather than increased (50). A recently published meta-analysis reported that the overall sensitivity and specificity of circulating miR-126 for MPM were 0.71 and 0.69, respectively (51), showing a limited diagnostic performance. ...
Background and objective:
The prognosis of patients with malignant pleural mesothelioma (MPM) is poor, and early diagnosis is key to improving the prognosis. Pleural biopsy is the gold reference for diagnosing MPM, but it is an invasive method that can cause operation-related complications such as bleeding and infection. Serum biomarkers, with the advantages of mini-invasiveness, short turnaround time and objectiveness, represent a promising diagnostic tool for MPM.
Methods:
We searched the PubMed database to identify clinical studies published between 1990 to July 2022 that investigated the diagnostic accuracy of serum biomarkers for MPM. The major findings of the verified studies were summarized.
Key content and findings:
Currently, there are many available serum markers for MPM, including mesothelin, soluble mesothelin-related peptides, osteopontin, fibulin-3, high mobility group box 1, and microRNA. Systematic review and meta-analysis evidence indicates that the sensitivity and specificity of these serum markers are less than 0.90. In addition, a large portion of previous studies have limitations, especially the representativeness of the study cohort.
Conclusions:
The diagnostic accuracy of currently available serum biomarkers is unsatisfactory, and further studies are needed to investigate novel serum biomarkers.
... Noticeably, the diagnostic performance of miR-126-3p seemed significantly improved when combined with the analysis of mesothelin and methylation of the thrombomodulin promoter (AUC 0.857, 95% CI 0.767-0.927) [93]. ...
Malignant pleural mesothelioma (MPM) is a clinical emergency of our time. Being strongly associated with asbestos exposure, incidence of this cancer is ramping up these days in many industrialized countries and it will soon start to increase in many developing areas where the use of this silicate derivate is still largely in use. Deficiency of reliable markers for the early identification of these tumors and the limited efficacy of the currently available therapeutic options are the basis of the impressive mortality rate of MPM. These shortcomings reflect the very poor information available about the molecular basis of this disease. Results of the recently released deep profiling studies point to the epigenome as a central element in MPM development and progression. First, MPM is characterized by a low mutational burden and a highly peculiar set of mutations that hits almost exclusively epigenetic keepers or proteins controlling chromatin organization and function. Furthermore, asbestos does not seem to be associated with a distinctive mutational signature, while the precise mapping of epigenetic changes caused by this carcinogen has been defined, suggesting that alterations in epigenetic features are the driving force in the development of this disease. Last but not least, consistent evidence also indicates that, in the setting of MPM, chromatin rewiring and epigenetic alterations of cancer cells heavily condition the microenvironment, including the immune response. In this review we aim to point to the relevance of the epigenome in MPM and to highlight the dependency of this tumor on chromatin organization and function. We also intend to discuss the opportunity of targeting these mechanisms as potential therapeutic options for MPM.
... The primary anticipated function of AMP-001-003 was to see if they synergize with the frontline chemotherapy such as doxorubicin or paclitaxel used for treating TNBC patients. In general, synergistic effect is measured through combination index (CI) calculations generated through isobolograms [43,44] (Fig 1B, S2A and S2B Fig). AMP-001/002/003 were incubated with MDA-MB-231 and TNBC subsets of cells (BT549, WHIM12) at a fixed dose 20 μM, varying doxorubicin concentration. ...
Cancer cells develop tactics to circumvent the interventions by desensitizing themselves to interventions. Amongst many, the principle routes of desensitization include a) activation of survival pathways (e.g. NF-kB, PARP) and b) downregulation of cell death pathways (e.g. CD95/CD95L). As a result, it requires high therapeutic dose to achieve tumor regression which, in turn damages normal cells through the collateral effects. Methods are needed to sensitize the low and non-responsive resistant tumor cells including cancer stem cells (CSCs) in order to evoke a better response from the current treatments. Current treatments including chemotherapy can induce cell death only in bulk cancer cells sparing CSCs and cancer resistant cells (CRCs) which are shown to be responsible for high recurrence of disease and low patient survival. Here, we report several novel tumor targeted sensitizers derived from the natural Vitamin E analogue (AMP-001-003). The drug design is based on a novel concept "A priori activation of apoptosis pathways of tumor technology (AAAPT) which is designed to activate specific cell death pathways and inhibit survival pathways simultaneously and selectively in cancer cells sparing normal cells. Our results indicate that AMP-001-003 sensitize various types of cancer cells including MDA-MB-231 (triple negative breast cancer), PC3 (prostate cancer) and A543 (lung cancer) cells resulting in reducing the IC-50 of doxorubicin in vitro when used as a combination. At higher doses, AMP-001 acts as an anti-tumor agent on its own. The synergy between AMP-001 and doxorubicin could pave a new pathway to use AAAPT leading molecules as neoadjuvant to chemotherapy to achieve better efficacy and reduced off-target toxicity compared to the current treatments.
... Thus, in a subset of cases, methylation of MSLN is retained and explains for the poor sensitivity of SMRP assay for pleural MM detection suggesting a need for additional biomarkers for MM detection. Santarelli et al. [69] combined methylated thrombomodulin promoter (Met-TM) and miR-126, two epigenetically regulated markers, with SMRPs for early MM detection in 188 subjects (99 asbestos-exposed patients, 45 MM patients and 44 healthy volunteers as control). It was found that the addition of epigenetically regulated biomarkers to SMRPs provided considerable improvements over the current diagnostic approaches by minimizing false positive and negative SMRP tests. ...
Malignant mesothelioma (MM) is a cancer of the mesothelial lining of the pleura, peritoneum, pericardium and testes. The most common form is asbestos-linked MM that is etiologically linked to repeated asbestos exposure with a long latency period, although non-asbestos MM has also been reported. Late diagnosis, poor survival rates, lack of diagnostic and prognostic markers act as major impediments in the clinical management of MM. Despite advances in immune checkpoint inhibition and CAR T-cell-based therapies, MM which is of different histologic subtypes remains challenging to treat. We review microRNAs (miRNAs) and the miRNA interactome implicated in MM which can be useful as circulating miRNA biomarkers for early diagnosis of MM and as biomarkers for prognostication in MM. Further, we underscore the relevance of the NRF2/MAPK signal transduction pathway that has been implicated in MM which may be useful as druggable targets or as biomarkers of predictive response. In addition, since MM is driven partly by inflammation, we elucidate chemopreventive phytochemicals that are beneficial in MM either via crosstalk with the NRF2/MAPK pathway or via concerted anticancer mechanisms and may be of benefit as adjuvants in chemotherapy. Taken together, a multifactorial approach comprising identification of miRNA target hubs and NRF2/MAPK biomarkers along with appropriately designed clinical trials may enable early detection and faster intervention in MM translating into better patient outcomes for this aggressive cancer.
... Taking into account the limitations mentioned above, many authors (74,83,85,94,102) suggested to explore together markers of different origin to overcome the poor sensitivity and specificity of single markers. These studies combine proteins (e.g., mesothelin, fibulin, and osteopontin concentration) and different epigenetic biomarkers, including DNA methylation, expression of miRNA, and also expression of long-noncoding RNAs (lncRNAs), which are non-coding RNAs mostly involved in transcriptional regulation (103). ...
Malignant pleural mesothelioma (MPM) is a rare and aggressive cancer, which originates from the mesothelial cells of the pleura and is associated with asbestos exposure. In light of its aggressive nature, late diagnosis and dismal prognosis, there is an urgent need for identification of biomarkers in easily accessible samples (such as blood) for early diagnosis of MPM. In the last 10 years, epigenetic markers, such as DNA methylation and microRNAs (miRNAs), have gained popularity as possible early diagnostic and prognostic biomarkers in cancer research. The aim of this review is to provide a critical analysis of the current evidences on circulating epigenetic biomarkers for MPM and on their translational potential to the clinical practice for early diagnosis and for prognosis.
... 16,[39][40][41][42][43][44][45] Additionally, recent studies suggest that a combination of different biomarkers could improve the predictive capacity of SMRP. 41,42,44,46,47 Our present results show that genetic variability affecting the expression of these biomarkers should also be taken into account. ...
Background
Asbestos exposure is associated with increased risk of several diseases, including malignant mesothelioma (MM). Cell surface glycoprotein mesothelin is overexpressed in MM and serum soluble mesothelin-related peptides (SMRP) were already proposed as a diagnostic or prognostic biomarker in MM. However, interindividual variability in serum SMRP levels limits the clinical usefulness. Our primary objective was to investigate the influence of MSLN rs1057147 on serum SMRP levels in asbestos-exposed subjects and patients with asbestos-related diseases as well as on survival in MM.
Subjects and methods
Among 782 asbestos-exposed subjects and patients with asbestos-related diseases, 154 had MM. Serum SMRP levels were determined using sandwich enzyme-linked immunosorbent assay. All subjects were genotyped for MSLN rs1057147 polymorphism using competitive allele-specific polymerase chain reaction. Nonparametric tests, logistic and Cox regression were used in statistical analysis to compare different subject groups.
Results
MM patients had significantly higher SMRP levels than all other subjects ( p < 0.001). Compared to wild-type MSLN rs1057147 genotype, both heterozygotes and carriers of two polymorphic alleles had significantly higher SMRP levels among subjects without MM ( p < 0.001), but not in MM patients ( p = 0.424). If genotype information was included, specificity of SMRP increased from 88.5% to 92.7% for the optimal cutoff value. Overall survival was significantly shorter in MM patients carrying at least one polymorphic rs1057147 allele (HR = 1.72, 95% CI = 1.15-2.55, p = 0.008).
Conclusions
MSLN genetic variability affects serum SMRP levels and was associated with shorter survival of MM patients. Combination of genetic and serum factors could therefore serve as a better diagnostic or prognostic biomarker in MM patients.
... A previous study reported that thrombomodulin (TM) is silenced in MM via a mechanism involving PARP1mediated methylation of the TM promoter . Aberrantly methylated TM DNA sequences (Met-TM) can be detected in serum and in combination with miR-126 and SMRPs represents a considerable improvement over the current diagnostic approaches, minimizing false-negative and false-positive SMRP tests (Santarelli et al., 2015). Recently, four serum miRNAs, i.e. miR-126, miR-205, miR-222 and miR-520g, were found to be implicated in asbestos-related malignancies (Santarelli et al., 2018). ...
In Italy, asbestos has been extensively used from 1945 to 1992. The Eternit settlements were widespread across Italy, and Ancona was one of the cities where asbestos was highly used. Ancona University was founded in 1969 and the Occupational Medicine Institute as part of Ancona hospital in collaboration with the Clinic Oncology mainly focused on asbestos-related diseases, both benign (asbestosis and pleural plaques) and malignant diseases such as malignant mesothelioma and lung cancer. Far in 1995, Governa and colleagues first evaluated ‘in vitro’ the biological effect of asbestos fibers. The studies carried on the asbestos carcinogenicity further contributed to identify biomarkers as indicators of cancer risk. Recently, new molecular biomarkers have been identified which can detect the malignancy at early stage, and the biomarker combination further improved the performance in the diagnosis of malignant mesothelioma. The prognostic performance status, and response to first-line chemotherapy was also evaluated in asbestos-related malignancies, and new molecular targets and therapeutic approach have been proposed.
... The primary anticipated function of AMP-001-003 was to see if they synergize with the frontline chemotherapy such as doxorubicin or paclitaxel, particularly for treating TNBC patients. In general, synergistic effect is measured through combination index (CI) calculations [28][29] (Fig 1 B). times compared to individual drugs (Fig 1 A). ...
Cancer cells develop tactics to circumvent the interventions by desensitizing themselves to interventions. The principle routes of desensitization include a) activation of survival pathways (e.g. NF-kB, PARP) and b) downregulation of cell death pathways (e.g. CD95/CD95L). As a result, it requires high therapeutic dose to achieve tumor regression which, in turn damages normal cells through the collateral damaging effects. Methods are needed to sensitize the low and non-responsive resistant tumor cells including cancer stem cells (CSCs) in order to evoke a better response from the current treatments. Current treatments including chemotherapy can induce cell death only in bulk cancer cells sparing CSCs and cancer resistant cells (CRCs) which are shown to be responsible for high recurrence of disease and low patient survival. Here, we report several novel tumor targeted sensitizers derived from the natural Vitamin E analogue (AMP-001-003). The drug design is based on a novel concept “A priori activation of apoptosis pathways of tumor technology (AAAPT) which is designed to activate specific cell death pathways and inhibit survival pathways simultaneously. Our results indicate that AMP-001-003 sensitize various types of cancer cells including MDA-MB-231 (triple negative breast cancer), PC3 (prostate cancer) and A543 (ling cancer) cells resulting in reducing the IC-50 of doxorubicin in vitro . At higher dose, AMP-001 acts as an anti-tumor agent on its own. The synergy between AMP-001 and doxorubicin could pave a new pathway to use AMP-001 as a neoadjuvant to chemotherapy to achieve a better efficacy and reduced off-target toxicity by the current treatments.
Summary Statement
A Priori Activation of Apoptosis Pathways of Tumor often referred to as “AAAPT” is a novel targeted tumor sensitizing technology which synergizes with chemotherapy to enhance the treatment efficacy.
... The primary anticipated function of AMP-001-003 was to see if they synergize with the frontline chemotherapy such as doxorubicin or paclitaxel, particularly for treating TNBC patients. In general, synergistic effect is measured through combination index (CI) calculations [28][29] (Fig 1 B). ...
Cancer cells develop tactics to circumvent the interventions by desensitizing themselves to interventions. The principle routes of desensitization include a) activation of survival pathways (e.g. NF-kB, PARP) and b) downregulation of cell death pathways (e.g. CD95/CD95L). As a result, it requires high therapeutic dose to achieve tumor regression which, in turn damages normal cells through the collateral damaging effects. Methods are needed to sensitize the low and non-responsive resistant tumor cells including cancer stem cells (CSCs) in order to evoke a better response from the current treatments. Current treatments including chemotherapy can induce cell death only in bulk cancer cells sparing CSCs and cancer resistant cells (CRCs) which are shown to be responsible for high recurrence of disease and low patient survival. Here, we report several novel tumor targeted sensitizers derived from the natural Vitamin E analogue (AMP-001-003). The drug design is based on a novel concept “A priori activation of apoptosis pathways of tumor technology (AAAPT) which is designed to activate specific cell death pathways and inhibit survival pathways simultaneously. Our results indicate that AMP-001-003 sensitize various types of cancer cells including MDA-MB-231 (triple negative breast cancer), PC3 (prostate cancer) and A543 (ling cancer) cells resulting in reducing the IC-50 of doxorubicin in vitro . At higher dose, AMP-001 acts as an anti-tumor agent on its own. The synergy between AMP-001 and doxorubicin could pave a new pathway to use AMP-001 as a neoadjuvant to chemotherapy to achieve a better efficacy and reduced off-target toxicity by the current treatments.
Summary Statement
A Priori Activation of Apoptosis Pathways of Tumor often referred to as “AAAPT” is a novel targeted tumor sensitizing technology which synergizes with chemotherapy to enhance the treatment efficacy.
... MicroRNAs have become attractive targets as novel biomarkers for MPM [13,14,[21][22][23]. MicroRNAs can be easily quantitated in a range of tissue types in an unbiased manner. ...
Malignant pleural mesothelioma (MPM) is an incurable cancer of the pleura that can be difficult to diagnose. Biomarkers for an easier and/or earlier diagnosis are needed. Approximately 90% of MPM patients develop a pleural effusion (PE). PEs are ideal sources of biomarkers as the fluid would almost always require drainage for diagnostic and/or therapeutic reasons. However, differentiating MPM PE from PE caused by other diseases can be challenging. MicroRNAs are popular biomarkers given their stable expression in tissue and fluid. MicroRNAs have been analysed in PE cytology samples for the diagnosis of MPM but have not been measured in frozen/fresh PE. We hypothesise that microRNAs expressed in PE are biomarkers for MPM. TaqMan OpenArray was used to analyse over 700 microRNAs in PE cells and supernatants from 26 MPMs and 21 other PE-causing diseases. In PE cells, combining miR-143, miR-210, and miR-200c could differentiate MPM with an area under the curve (AUC) of 0.92. The three-microRNA signature could also discriminate MPM from a further 40 adenocarcinomas with an AUC of 0.9887. These results suggest that the expression of miR-143, miR-210, and miR-200c in PE cells might provide a signature for diagnosing MPM.
... There are a number of comprehensive studies in the literature investigating potential biomarkers for the early diagnosis of MM in symptomatic patients exhibiting past exposure to asbestos. Among these, Mesothelin is one of the several well-known biomarkers used in the diagnosis of pleural MM [42][43][44][45]. ...
Since 1973 the International Agency for Research on Cancer has classified asbestos as a certain carcinogen, but today it is still used in several countries. To date, mesothelioma risk is certainly linked not only to occupational exposures but also to environmental exposures. The incidence and mortality are increasing worldwide, especially in developing countries where asbestos is still often used without adequate measures for worker safety. The epidemiological surveillance systems of related asbestos diseases are instruments of public health adopted internationally. The experience and the operating methodology of the Italian mesothelioma registry and the data produced from 1996 to 2015 highlight how in countries where the asbestos ban has been active for over 20 years the risk of asbestos remains present, especially in the construction sector as well as for the environmental exposures of the resident population near companies that used asbestos in their production cycle. Worldwide, it is necessary to introduce the ban on the extraction, processing, and marketing of asbestos as claimed by the international scientific community.
... This sensitivity and specificity of mesothelioma patient testing increased from 74% and 89% to 95% and 81%, for mesothelin alone or combination testing, respectively. More recently studies show increased diagnostic significance for changes in the combination levels for miR-26, methylated thrombomodulin, and soluble mesothelin that are superior to current available screening tests (Santarelli et al. 2015). ...
Our current understanding of mesothelioma in terms of disease induction, development, and treatment is underpinned by decades of basic laboratory science. In this chapter, we discuss the tools that have been developed to aid our understanding of mesothelioma such as cell lines and animal models. We then go on to detail the current use and understanding of conventional therapies for mesothelioma, e.g. chemotherapy, surgery, and radiotherapy, plus their mechanisms of action, and why they may be ineffective. Finally, we discuss a range of newer treatments that are either undergoing clinical trials or are still in the earlier stages of preclinical investigation. These include a growing number of immunotherapies (e.g. checkpoint inhibitors), plus targeted therapies, the search for clinical biomarkers to predict whether patients with mesothelioma might respond to particular treatments, and combined therapies where conventional treatments may be added to newer drugs. The strategy of repositioning existing drugs, approved for other diseases, to treat mesothelioma is also discussed.
... Moreover, in non-neoplastic subjects, the association between high SMRP levels and high Met-TM or low miR-16 levels, increased significantly the MPM risk. These data were confirmed in a validation cohort of 20 healthy controls, 50 asbestos-exposed subjects, 18 MPM, and 42 lung cancer patients (63). ...
Malignant pleural mesothelioma (MPM) is a rare and aggressive tumor with a variable incidence among different countries. Occupational asbestos exposure is the most important etiological factor and a very long latency period is widely reported. In the early phase of the disease, clinical signs are absent or not specific. For this reason, the diagnosis is frequently achieved only in the advanced stages. The histopathological diagnosis per se is also very complex, and no known factor can predict the prognosis with certainty. Nonetheless, current survival rates remain very low, despite the use of standard treatments, which include surgery, chemotherapy and radiotherapy. The identification of new prognostic and/or diagnostic biomarkers, and the discovery of therapeutic targets is a priority and could lead to a real significant impact on the management of malignant pleural mesothelioma. In this scenario, the role of microRNAs is becoming increasingly relevant, with the promise of a quick translation in the current clinical practice. Despite the relative novelty of this field, the number of works and candidate microRNAs that are present in literature is striking. Unfortunately, to date the microRNAs with the most clinical relevance for MPM are still matter of debate, probably due to the variety of approaches, techniques, and collected samples. Although specific microRNAs (e.g., let-7, miR-15 and miR-16, miR-21, miR-34a, and the miR-200 family) have been reported several times from different groups, the heterogeneity of published data reinforces the need of more comprehensive and unified studies on this topic. In this review we collect and discuss the studies focused on the involvement of microRNAs in different aspects of MPM, from their biological role in tumorigenesis and progression, to their possible application as diagnostic, prognostic and predictive biomarkers. Lastly, we examine their potential value as for the design of therapeutic approaches that could benefit MPM patients.
... Furthermore, for some tumours, e.g. mesothelioma, no standardized approach has been developed and further studies are needed [269][270][271]. ...
Malignant pleural effusions (MPE) are a common pathology, treated by respiratory physicians and thoracic surgeons alike. In recent years, several well-designed randomized clinical trials have been published that have changed the landscape of MPE management. The European Respiratory Society (ERS) and the European Association for Cardio-Thoracic Surgery (EACTS) established a multidisciplinary collaboration of clinicians with expertise in the management of MPE with the aim of producing a comprehensive review of the scientific literature. Six areas of interest were identified, including the optimum management of symptomatic MPE, management of trapped lung in MPE, management of loculated MPE, prognostic factors in MPE, whether there is a role for oncological therapies prior to intervention for MPE and whether a histological diagnosis is always required in MPE. The literature revealed that talc pleurodesis and indwelling pleural catheters effectively manage the symptoms of MPE. There was limited evidence regarding the management of trapped lung or loculated MPE. The LENT score was identified as a validated tool for predicting survival in MPE, with Brims' prognostic score demonstrating utility in mesothelioma prognostication. There was no evidence to support the use of oncological therapies as an alternative to MPE drainage, and the literature supported the use of tissue biopsy as the gold standard for diagnosis and treatment planning.
Management options for malignant pleural effusions have advanced over the past decade, with high-quality randomized trial evidence informing practice in many areas. However, uncertainties remain and further research is required http://ow.ly/rNt730jOxOS
... Furthermore, for some tumours, e.g. mesothelioma, no standardised approach has been developed and further studies are needed [269][270][271]. In summary Cytology can provide useful diagnostic, prognostic and therapeutic information; however, low sensitivity remains an issue, especially in mesothelioma. ...
Malignant pleural effusions (MPE) are a common pathology, treated by respiratory physicians and thoracic surgeons alike. In recent years, several well-designed randomised clinical trials have been published that have changed the landscape of MPE management. The European Respiratory Society (ERS) and the European Association for Cardio-Thoracic Surgery (EACTS) established a multidisciplinary collaboration of clinicians with expertise in the management of MPE with the aim of producing a comprehensive review of the scientific literature.
Six areas of interest were identified, including the optimum management of symptomatic MPE, management of trapped lung in MPE, management of loculated MPE, prognostic factors in MPE, whether there is a role for oncological therapies prior to intervention for MPE and whether a histological diagnosis is always required in MPE.
The literature revealed that talc pleurodesis and indwelling pleural catheters effectively manage the symptoms of MPE. There was limited evidence regarding the management of trapped lung or loculated MPE. The LENT score was identified as a validated tool for predicting survival in MPE, with Brims' prognostic score demonstrating utility in mesothelioma prognostication. There was no evidence to support the use of oncological therapies as an alternative to MPE drainage, and the literature supported the use of tissue biopsy as the gold standard for diagnosis and treatment planning.
... SMRPs diagnostic value has been evaluated also in pleural effusion (25,26,29) and it has been observed a higher diagnostic performance in pleural effusion than in serum assessment (22). The need to detect the MPM at the early stages led several authors to investigate whether mesothelin can contribute towards the evaluation of the carcinogenic risk in populations exposed to asbestos: high level of SMRPs have been proposed as a marker for early diagnosis in combination with two epigenetic marker (27) or alone (28). Interestingly higher levels of SMRP have been found in the asbestos exposure group than in the control group and the increment observed was gradual among the controls, the asbestos exposed and mesothelioma patients (28). ...
Malignant pleural mesothelioma (MPM) is a very aggressive cancer poorly responsive to current therapies. MPM patients have a very poor prognosis with a median survival of less than one year from the onset of symptoms. The biomarkers proposed so far do not lead to a sufficiently early diagnosis for a radical treatment of the disease. Thus, the finding of novel diagnostic and prognostic biomarkers and therapeutic targets is needed. Gene overexpression has been frequently associated with a malignant phenotype in several cancer types; therefore the identification of overexpressed genes may lead to the detection of novel prognostic or diagnostic marker and to the development of novel therapeutic approaches, based on their inhibition. In the last years, several overexpressed genes have been identified in MPM through gene expression profiling techniques: among them it has been found a group of 51 genes that resulted overexpressed in more than one independent study, revealing their consistency among studies. This article reviews the clinical implications of confirmed overexpressed genes in MPM described so far in literature.
... Combinations of markers from different molecular levels, e.g. proteins, methylated DNA, and microRNA as shown by Santarelli et al., appear to be a promising approach [33]. Recently, Bononi et al. discovered new circulating microRNAs that were upregulated in MM cases compared to asbestos-exposed controls; for example, miR-197-3p showed an AUC of 0.76 in the ROC analysis [34]. ...
Background
Malignant mesothelioma (MM) is a deadly cancer mainly caused by previous exposure to asbestos. With a latency period up to 50 years the incidence of MM is still increasing, even in countries that banned asbestos. Secondary prevention has been established to provide persons at risk regular health examinations. An earlier detection with tumor markers might improve therapeutic options. Previously, we have developed a new blood-based assay for the protein marker calretinin. Aim of this study was the verification of the assay in an independent study population and comparison with the established marker mesothelin.
Methods
For a case-control study in men, a total of 163 cases of pleural MM and 163 controls were available from Australia, another 36 cases and 72 controls were recruited in Germany. All controls had asbestosis and/or plaques. Calretinin and mesothelin were determined by ELISA (enzyme-linked immunosorbent assay) in serum or plasma collected prior to therapy. We estimated the performance of both markers and tested factors potentially influencing marker concentrations like age, sample storage time, and MM subtype.
Results
Calretinin was able to detect all major subtypes except for sarcomatoid MM. Calretinin showed a similar performance in Australian and German men. At a pre-defined specificity of 95% the sensitivity of calretinin reached 71% and that of mesothelin 69%, when excluding sarcomatoid MM. At 97% specificity, the combination with calretinin increased the sensitivity of mesothelin from 66% to 75%. Sample storage time did not influence the results. In controls the concentrations of calretinin increased 1.87-fold (95% CI 1.10–3.20) per 10 years of age and slightly more for mesothelin (2.28, 95% CI 1.30–4.00).
Conclusions
Calretinin could be verified as a blood-based marker for MM. The assay is robust and shows a performance that is comparable to that of mesothelin. Retrospective analyses would not be limited by storage time. The high specificity supports a combination of calretinin with other markers. Calretinin is specific for epithelioid and biphasic MM but not the rarer sarcomatoid form. Molecular markers like calretinin and mesothelin are promising tools to improve and supplement the diagnosis of MM and warrant further validation in a prospective study.
Electronic supplementary material
The online version of this article (doi:10.1186/s12885-017-3375-5) contains supplementary material, which is available to authorized users.
... As in any other type of cancer, a biomarker combination could improve both sensitivity and specificity. In recent years, SMRP and/or pOPN were combined with other biomarkers, as CA125, CEA, and MPF (Megakaryocyte Potentiating Factor) [14][15][16][17]. All these combinations were performed using biomarkers already known for their employment in diagnosis of cancer different from MPM. Probably for this reason, biomarker combination did not reach appropriate values of sensitivity and specificity. ...
Exposure to asbestos is the main cause of malignant pleural mesothelioma (MPM), a highly aggressive cancer of the pleura. Since the only tools for early detection are based on radiological tests, some authors focused on serum markers (i.e., mesothelin). The aim of this study was the evaluation of new serum biomarkers to be used individually or in combination, in order to improve the outcome of patients whose disease would be diagnosed at an earlier stage. Serum and plasma were available from 43 subjects previously exposed to asbestos and 27 MPM patients, all being epithelioid type. All the new markers found differentially expressed in MPM and healthy subjects, by proteomic and genomic approaches, have been validated in the serum by the use of specific ELISA. The combined approach, using tools of genomics and proteomics, is found to be highly innovative for this type of disease and led to the identification of new serum markers in the diagnosis of MPM. These results, if confirmed in a larger series, may have a strong impact in this area, because early detection of this cancer in people at high risk could significantly improve the course of the disease and the clinical approach to an individualized therapy.
Pleural mesothelioma (PM) is a type of cancer that is highly related to exposure to asbestos fibers. It shows aggressive behavior, and the current therapeutic approaches are usually insufficient to change the poor prognosis. Moreover, apart from staging and histological classification, there are no validated predictors of its response to treatment or its long-term outcomes. Numerous studies have investigated minimally invasive biomarkers in pleural fluid or blood to aid in earlier diagnosis and prognostic assessment of PM. The most studied marker in pleural effusion is mesothelin, which exhibits good specificity but low sensitivity, especially for non-epithelioid PM. Other biomarkers found in pleural fluid include fibulin-3, hyaluronan, microRNAs, and CYFRA-21.1, which have lower diagnostic capabilities but provide prognostic information and have potential roles as therapeutic targets. Serum is the most investigated matrix for biomarkers of PM. Several serum biomarkers in PM have been studied, with mesothelin, osteopontin, and fibulin-3 being the most often tested. A soluble mesothelin-related peptide (SMRP) is the only FDA-approved biomarker in patients with suspected mesothelioma. With different serum and pleural fluid cut-offs, it provides useful information on the diagnosis, prognosis, follow-up, and response to therapy in epithelioid PM. Panels combining different markers and proteomics technologies show promise in terms of improving clinical performance in the diagnosis and monitoring of mesothelioma patients. However, there is still no evidence that early detection can improve the treatment outcomes of PM patients.
Background.
Malignant Pleural Mesothelioma (MPM) is an aggressive cancer with a dismal prognosis. Early therapeutic interventions could improve patient outcomes.
We aimed at identifying a pattern of microRNAs (miRNAs) as potential early non-invasive markers of MPM.
Methods.
In a case–control study nested in the European Prospective Investigation into Cancer and nutrition cohort, we screened the whole miRNome in serum extracellular vesicles (EVs) of preclinical MPM cases, by means a next generation sequencing approach.
In a case–control study nested in the European Prospective Investigation into Cancer and nutrition (EPIC) cohort, we screened the whole miRNome in serum extracellular vesicles (EVs) derived from 80 pre-clinical cases of MPM (median time to diagnosis = 8 years) and 80 matched cancer-free controls.
Results.
We did not detect any miRNA in serum EVs significantly differentially expressed between 80 pre-clinical MPM and matched controls. On the other hand, in a subgroup of 20 preclinical samples collected five years prior MPM diagnosis, we observed an up-regulation of miR-11400 (Fold change =2.6, adjusted p-value=0.01), miR-148a-3p (Fold change =1.5, p-value=0.001) and miR-409-3p (Fold change =1.5, p-value=0.04) respect to matched controls. The three-miRNA panel showed a good classification capacity with an area under the receiver operating characteristic curve (AUC) of 0.81 (specificity=0.75, sensitivity=0.70). The diagnostic ability of the model was also evaluated in an independent retrospective cohort, yielding a higher predictive power (AUC = 0.86).
Conclusions.
A signature of EV miRNA can be detected up to five years before MPM; moreover, the identified miRNAs could provide functional insights into the molecular changes related to the late carcinogenic process, preceding MPM development. However, the potential role of the three identified miRNAs requires further validation in a larger independent MPM prospective study.
Pleural malignant mesothelioma (MM), which arises from the cells that line the lung and the chest cavity (pleura), is a highly aggressive tumor with a high recurrence rate after surgical resection, and is insensitive to chemotherapy and radiotherapy. miRNAs have been proved to play a key role in cancer progression, early screening, diagnosis, and treatment response.
Malignant pleural mesothelioma (MPM) is a rare form of tumor, linked with occupational and environmental exposure to a class of mineral fibers, collectively known as asbestos. Although asbestos has been banned in several developed countries, MPM is still a public health problem. Due to the late onset of symptoms, the diagnosis occurs at advanced stages. The lack of noninvasive and early detection procedures, together with the lack of effective treatments, are significant challenges for clinicians. In this scenario, microRNAs (miRNAs) have emerged as new biomarkers in clinical diagnosis and treatment of MPM. The aim of this chapter is to summarize the current knowledge regarding the role of miRNAs in MPM onset, the relevant changes found in MPM cells and tumor tissue, as well as the potential application of these findings in the clinics as potential biomarkers and therapeutic tool.
Malignant pleural mesothelioma (MPM) is characterised by late-stage diagnosis and poor prognosis. Currently, no screening tool is advocated and diagnosis is based on invasive techniques, which are not well tolerated. Non-invasive diagnostic biomarkers have shown potential and could have a huge clinical benefit. However, despite extensive research, there is no consensus yet on their clinical use, with many articles reporting contradicting results, limiting their clinical implementation. The aim of this systematic review is therefore to explore the different semi- and non-invasive diagnostic markers in several human matrices and identify those that might clinically be relevant. A total of 100 articles were selected through Web of Science and PubMed, with 56 articles included in the quantitative analysis. Although many studies have reported on the diagnostic accuracy of MPM biomarkers such as serum mesothelin and high-mobility group box protein 1 and plasma fibulin-3, none have resulted in a validated test for early detection. Future research should focus on external validation, combinations into biomarker panels, the inclusion of early stage MPM patients and a combination of different biomarker matrices, as well as new markers.
Malignant pleural mesothelioma (MPM) is an asbestos-related neoplasm that can only be treated successfully when correctly diagnosed and treated early. The asbestos-exposed population is a high-risk group that could benefit from sensitive and specific blood- or tissue-based biomarkers. We review recent work with biomarker development in MPM and literature of the last 20 years on the most promising blood- and tissue-based biomarkers. Proteomic, genomic, and epigenomic platforms are covered. SMRP is the only validated blood-based biomarker with diagnostic, monitoring and prognostic value. To strengthen development and testing of MPM biomarkers, cohorts for validation must be established by enlisting worldwide collaborations.
Malignant pleural mesothelioma (MPM) is an aggressive asbestos related disease that is generally considered to be difficult to diagnose, stage and treat. The diagnostic process is continuing to evolve and requires highly skilled pathology input, and generally an extensive list of biomarkers for definitive diagnosis. Diagnosis of MPM requires histological evidence of invasion by malignant mesothelial cells often confirmed by various immunohistochemical biomarkers in order to separate it from pleural metastatic carcinoma. Often when invasion of neoplastic mesothelial cells into adjacent tissue is not apparent, further immunohistochemical testing - namely BAP1 and MTAP, as well as FISH testing for loss of p16 (CDKN2A) are used to separate reactive mesothelial proliferation due to benign processes, from MPM. Various combinations of these markers, such as BAP1 and/or MTAP immunohistochemistry alongside FISH testing for loss of p16, have shown excellent sensitivity and specificity in the diagnosis of MPM. Additionally, over the recent years, research into epigenetic marker use in the diagnosis of MPM has gained momentum. Although still in their research stages, various markers in DNA methylation, long non-coding RNA, micro RNA, circular RNA, and histone modifications have all been found to support diagnosis of MPM with generally good sensitivity and specificity. Many of these studies are however, limited by small sample sizes or other study limitations and further research into the area would be beneficial. Epigenetic markers show promise for use in the future to facilitate the diagnosis of MPM.
Background:
Malignant Pleural Mesothelioma (MPM) is an asbestos related neoplasm which can only be treated successfully when correctly diagnosed and treated in early stages. The asbestos exposed population serves as a high risk group which could benefit from sensitive and specific blood based or tissue based biomarkers. This review details the recent work with biomarker development in MPM and the contributions of the NCI Early Detection Research Network Biomarker Developmental Laboratory of NYU Langone Medical Center.
Methods:
The literature of the last 20 years was reviewed in order to comment on the most promising of the blood and tissue based biomarkers. Proteomic, genomic and epigenomic platforms as well as novel studies such as "breath testing" are covered.
Results:
Soluble Mesothelin-Related Proteins (SMRP) have been characterized extensively and constitute an FDA-approved biomarker in plasmawith diagnostic, monitoring and prognostic value in MPM. Osteopontin is found to be a valuable prognostic biomarker for MPM, while its utility in diagnosis is slightly lower. Other biomarkers such as calretinin, fibulin 3, and High-Mobility Group Box 1 (HMGB1) remain under study and need international validation trials with large cohorts of cases and controls to demonstrate any utility.
Conclusions:
The EDRN has played a key role in the development and testing of MPM biomarkers by enlisting collaborations all over the world.
Impact:
A comprehensive understanding of previously investigated biomarkers and their utility in screening and early diagnosis of MPM will provide guidance for further future research.
The European Respiratory Society (ERS)/European Society of Thoracic Surgeons (ESTS)/European Association for Cardio-Thoracic Surgery (EACTS)/European Society for Radiotherapy and Oncology (ESTRO) task force brought together experts to update previous 2009 ERS/ESTS guidelines on management of malignant pleural mesothelioma (MPM), a rare cancer with globally poor outcome, after a systematic review of the 2009-2018 literature. The evidence was appraised using the Grading of Recommendations, Assessment, Development and Evaluation approach. The evidence syntheses were discussed and recommendations formulated by this multidisciplinary group of experts. Diagnosis: pleural biopsies remain the gold standard to confirm the diagnosis, usually obtained by thoracoscopy but occasionally via image-guided percutaneous needle biopsy in cases of pleural symphysis or poor performance status. Pathology: standard staining procedures are insufficient in ∼10% of cases, justifying the use of specific markers, including BAP-1 and CDKN2A (p16) for the separation of atypical mesothelial proliferation from MPM. Staging: in the absence of a uniform, robust and validated staging system, we advise using the most recent 2016 8th TNM (tumour, node, metastasis) classification, with an algorithm for pretherapeutic assessment. Monitoring: patient's performance status, histological subtype and tumour volume are the main prognostic factors of clinical importance in routine MPM management. Other potential parameters should be recorded at baseline and reported in clinical trials. Treatment: (chemo)therapy has limited efficacy in MPM patients and only selected patients are candidates for radical surgery. New promising targeted therapies, immunotherapies and strategies have been reviewed. Because of limited data on the best combination treatment, we emphasize that patients who are considered candidates for a multimodal approach, including radical surgery, should be treated as part of clinical trials in MPM-dedicated centres.
The European Respiratory Society (ERS)/European Society of Thoracic Surgeons (ESTS)/European Association for Cardio-Thoracic Surgery (EACTS)/European Society for Radiotherapy and Oncology (ESTRO) task force brought together experts to update previous 2009 ERS/ESTS guidelines on management of malignant pleural mesothelioma (MPM), a rare cancer with globally poor outcome, after a systematic review of the 2009–2018 literature. The evidence was appraised using the Grading of Recommendations, Assessment, Development and Evaluation approach. The evidence syntheses were discussed and recommendations formulated by this multidisciplinary group of experts. Diagnosis: pleural biopsies remain the gold standard to confirm the diagnosis, usually obtained by thoracoscopy but occasionally via image-guided percutaneous needle biopsy in cases of pleural symphysis or poor performance status. Pathology: standard staining procedures are insufficient in ∼10% of cases, justifying the use of specific markers, including BAP-1 and CDKN2A ( p16 ) for the separation of atypical mesothelial proliferation from MPM. Staging: in the absence of a uniform, robust and validated staging system, we advise using the most recent 2016 8th TNM (tumour, node, metastasis) classification, with an algorithm for pre-therapeutic assessment. Monitoring: patient's performance status, histological subtype and tumour volume are the main prognostic factors of clinical importance in routine MPM management. Other potential parameters should be recorded at baseline and reported in clinical trials. Treatment: (chemo)therapy has limited efficacy in MPM patients and only selected patients are candidates for radical surgery. New promising targeted therapies, immunotherapies and strategies have been reviewed. Because of limited data on the best combination treatment, we emphasise that patients who are considered candidates for a multimodal approach, including radical surgery, should be treated as part of clinical trials in MPM-dedicated centres.
Malignant pleural mesothelioma (MPM) is an aggressive disease arising in pleural cell lining and is associated with asbestos exposure. Today, there is a rising incidence of MPM reaching 3,000 annual cases nationally, primarily from the large population occupationally exposed to asbestos between 1940 and 1980. With a prolonged latency period, presenting clinically 10 to 40 years after exposure, MPM is often diagnosed in late stages and presents median survival time of less than 12 months. There is a serious need for improvement in prognostic and diagnostic tools for MPM. Recent investigation and discovery of various biomarkers has shown promise, including Osteopontin, Fibulin-3, Soluble Mesothelin-Related Proteins (SMRP), High Mobility Group Box 1 (HMGB1), micro-RNA's, peripheral blood-based markers, and Slow Off-rate Modified Aptamer (SOMAmer) proteomic assays. In this review, we explore these current major biomarkers and their prognostic and diagnostic potential, highlighting the most recent large studies and developments for each. While progress has been made in mesothelioma research, many questions remain unanswered. Increased international cooperation is necessary for improving validity of results for current biomarkers through repeated investigation and increasing cohort sizes, as well as for the continued search for new and better markers.
Aims:
MiR126 was found to be frequently lost in many types of cancer, including malignant mesothelioma (MM), which represents one of the most challenging neoplastic diseases. In this study, we investigated the potential tumor suppressor function of MiR126 in MM cells. The effect of MiR126 was examined in response to oxidative stress, aberrant mitochondrial function induced by inhibition of complex I, mitochondrial DNA (mtDNA) depletion, and hypoxia.
Results:
MiR126 was up-regulated by oxidative stress in nonmalignant mesothelial (Met5A) and MM (H28) cell lines. In Met5A cells, rotenone inhibited MiR126 expression, but mtDNA depletion and hypoxia up-regulated MiR126. However, these various stimuli suppressed the levels of MiR126 in H28 cells. MiR126 affected mitochondrial energy metabolism, reduced mitochondrial respiration, and promoted glycolysis in H28 cells. This metabolic shift, associated with insulin receptor substrate-1 (IRS1)-modulated ATP-citrate lyase deregulation, resulted in higher ATP and citrate production. These changes were linked to the down-regulation of IRS1 by ectopic MiR126, reducing Akt signaling and inhibiting cytosolic sequestration of Forkhead box O1 (FoxO1), which promoted the expression of genes involved in gluconeogenesis and oxidative stress defense. These metabolic changes induced hypoxia-inducible factor-1α (HIF1α) stabilization. Consequently, MiR126 suppressed the malignancy of MM cells in vitro, a notion corroborated by the failure of H28(MiR126) cells to form tumors in nude mice.
Innovation and conclusion:
MiR126 affects mitochondrial energy metabolism, resulting in MM tumor suppression. Since MM is a fatal neoplastic disease with a few therapeutic options, this finding is of potential translational importance.
miR-126 is an endothelial-specific microRNA essential for maintaining vessel integrity during development. Its role of tumor angiogenesis in cancer stroma is unclear. This study investigated the temporal and spatial expression and the role of miR-126 in the course of cervical carcinogenesis. miR-126 was found to be mainly expressed in the stromal endothelium of the uterine cervix. This downregulation was recapitulated in a cell coculture model, wherein cross talk of cervical cancer cells and fibroblasts induced a downregulation of miR-126 in human umbilical vein endothelial cells, with consequent increase of tube formation. Coinjection of cancer-associated fibroblasts of human cervix enhanced tumorigenesis of cervical cancer cells, with an increase of microvessel density and dye retention in the tumor vasculature. In association with angiogenesis, host-originated miR-126 in these xenograft tumors was progressively downregulated, whereas supplement of the miR-126 precursor in the coinjection suppressed angiogenesis and tumor growth. A proangiogenic gene adrenomedullin (ADM), which was found to be upregulated in the stroma of cervical cancer and which localized mainly in the blood and lymphatic vessels, was identified as a target of inhibition by miR-126 at the carcinoma in situ-to-invasion stage. The study suggests a cancer stroma cross talk induced repression of miR-126 and upregulation of ADM, and probably other proangiogenic factors, to facilitate angiogenesis and invasion growth of cervical cancer.Oncogene advance online publication, 16 September 2013; doi:10.1038/onc.2013.335.
In cancer, the overall patterns of epigenetic marks are severely distorted from the corresponding normal cell type. It is now well established that these changes can contribute to cancer development through inactivation of tumor suppressor genes and, conversely, through activation of oncogenes. Recent technological advances have enabled epigenome-wide analyses of cancers that are yielding unexpected findings. The study of cancer epigenetics holds great promise for expanding the range of therapeutic opportunities for personalized medicine. Here, we focus on DNA methylation in breast cancer and the potential implications for clinical management of patients.
Imprinting is an important epigenetic regulator of gene expression that is often disrupted in cancer. While loss of imprinting (LOI) has been reported for two genes in prostate cancer (IGF2 and TFPI2), disease-related changes in methylation across all imprinted gene regions has not been investigated.
Using an Illumina Infinium Methylation Assay, we analyzed methylation of 396 CpG sites in the promoter regions of 56 genes in a pooled sample of 12 pairs of prostate tumor and adjacent normal tissue. Selected LOI identified from the array was validated using the Sequenom EpiTYPER assay for individual samples and further confirmed by expression data from publicly available datasets.
Methylation significantly increased in 52 sites and significantly decreased in 17 sites across 28 unique genes (P < 0.05), and the strongest evidence for loss of imprinting was demonstrated in tumor suppressor genes DLK1, PLAGL1, SLC22A18, TP73, and WT1. Differential expression of these five genes in prostate tumor versus normal tissue using array data from a publicly available database were consistent with the observed LOI patterns, and WT1 hypermethylation was confirmed using quantitative DNA methylation analysis.
Together, these findings suggest a more widespread dysregulation of genetic imprinting in prostate cancer than previously reported and warrant further investigation.
The tumour stroma is an active participant during cancer progression. Stromal cells promote tumour progression and metastasis through multiple mechanisms including enhancing tumour invasiveness and angiogenesis, and suppressing immune surveillance. We report here that miR-126/miR-126(*), a microRNA pair derived from a single precursor, independently suppress the sequential recruitment of mesenchymal stem cells and inflammatory monocytes into the tumour stroma to inhibit lung metastasis by breast tumour cells in a mouse xenograft model. miR-126/miR-126(*) directly inhibit stromal cell-derived factor-1 alpha (SDF-1α) expression, and indirectly suppress the expression of chemokine (C-C motif) ligand 2 (Ccl2) by cancer cells in an SDF-1α-dependent manner. miR-126/miR-126(*) expression is downregulated in cancer cells by promoter methylation of their host gene Egfl7. These findings determine how this microRNA pair alters the composition of the primary tumour microenvironment to favour breast cancer metastasis, and demonstrate a correlation between miR-126/126(*) downregulation and poor metastasis-free survival of breast cancer patients.
Significance
Increasing evidence supports the notion that an aberrant microenvironment facilitates cancer development. The mechanisms underlying the phenotypic changes and the tumor-promoting function of cancer-associated stroma remain largely unknown. Overexpression of the chromatin remodeling protein Hmga2 in the stroma leads to the formation of multifocal prostatic precancerous lesions in the neighboring naïve epithelium in a paracrine Wnt-dependent manner. The potent growth-promoting effects of Hmga2-modified stroma collaborate significantly with enhanced stromal AR signaling to drive the development of prostate adenocarcinoma. Our findings provide compelling evidence for the critical contribution of epigenetic changes in stromal cells to cancer initiation and progression.
Malignant pleural mesothelioma (MPM) is a highly aggressive tumor with poor prognosis. One major challenge for this disease is the development of new, early, and highly reliable diagnostic markers. The aim of this study was to compare the diagnostic value of the chemokine chemokine (C-C motif) ligand 2 (CCL2), galectin-3, and the secretory leukocyte peptidase inhibitor (SLPI) with soluble mesothelin-related peptides (SMRP), and to evaluate the diagnostic performance of marker combinations.
The levels of the different markers were measured by enzyme-linked immunosorbent assay in pleural fluids from patients with MPM (n = 61), adenocarcinomas (ADCA, n = 25), or with benign pleural effusions (BPE, n = 15).
SMRP, SLPI, and CCL2 concentrations were significantly higher in pleural effusions from mesothelioma patients. Conversely, galectin-3 levels seemed to be elevated in patients with pulmonary ADCA. Receiver operating characteristic curve analysis revealed that SMRP (area under the curve [AUC] = 0.9059), CCL2 (AUC = 0.7912), galectin-3 (AUC = 0.7584), and SLPI (AUC = 0.7219) were potentially interesting biomarkers for the differentiation of MPM patients from those with BPE or ADCA. Of interest, we showed that the combination of SMRP/CCL2/galectin-3 greatly improved MPM diagnosis (AUC = 0.9680), when compared with SMRP alone.
The combination of SMRP/CCL2/galectin-3 seems to represent a promising panel of biomarkers for the reliable diagnosis of MPM in pleural fluids.
Mesothelin is currently considered the best available serum biomarker of malignant pleural mesothelioma. To examine the diagnostic accuracy and use of serum mesothelin in early diagnosis, we performed an individual patient data (IPD) meta-analysis.
The literature search identified 16 diagnostic studies of serum mesothelin, measured with the Mesomark enzyme-linked immunosorbent assay. IPD of 4,491 individuals were collected, including several control groups and 1,026 patients with malignant pleural mesothelioma. Mesothelin levels were standardized for between-study differences and age, after which the diagnostic accuracy and the factors affecting it were examined with receiver operating characteristic (ROC) regression analysis.
At a common diagnostic threshold of 2.00 nmol/L, the sensitivities and specificities of mesothelin in the different studies ranged widely from 19% to 68% and 88% to 100%, respectively. This heterogeneity can be explained by differences in study population, because type of control group, mesothelioma stage, and histologic subtype significantly affected the diagnostic accuracy. The use of mesothelin in early diagnosis was evaluated by differentiating 217 patients with stage I or II epithelioid and biphasic mesothelioma from 1,612 symptomatic or high-risk controls. The resulting area under the ROC curve was 0.77 (95% CI, 0.73 to 0.81). At 95% specificity, mesothelin displayed a sensitivity of 32% (95% CI, 26% to 40%).
In patients suspected of having mesothelioma, a positive blood test for mesothelin at a high-specificity threshold is a strong incentive to urge further diagnostic steps. However, the poor sensitivity of mesothelin clearly limits its added value to early diagnosis and emphasizes the need for further biomarker research.
Malignant pleural mesothelioma (MPM) remains a cancer of poor prognosis. It is hoped that implementation of effective screening biomarkers will lead to earlier diagnoses and improved outcomes. Serum-measured soluble mesothelin-related peptide (SMRP) has been demonstrated to have excellent specificity for MPM, but poor sensitivity precludes its use as a screening biomarker. Using a case series of MPM patients from the International Mesothelioma Program at the Brigham and Women's hospital, we sought to determine whether epigenetic change at the MSLN gene in patient tumors is responsible for the poor sensitivity of SMRP. We identified three potential target regions for CpG methylation silencing in the MSLN promoter, one of which was amenable to bisulfite pyrosequencing and located 214 bp upstream of the transcription start site. MSLN promoter methylation was significantly higher in normal pleura than tumor tissue (P < 6.0x10-9). Next, we compared cases according to serum SMRP status and observed that MSLN methylation was significantly higher among tumors from patients testing negative for SMRP (< 1.5nM) versus those that were SMRP positive (P < 0.03). These results demonstrate that MSLN is normally methylated in the pleura, and that methylation is lost in most tumors. However, in a subset of tumors methylation is retained, and this mechanism explains the poor sensitivity of the SMRP assay. These results may lead to additional biomarker targets that will resolve the poor sensitivity of the SMRP assay and allow implementation of screening among exposed populations.
Hypermethylation of the RASSF1A [Ras association (RalGDS/AF-6) domain family member 1A] gene is frequently observed in hepatocellular carcinoma (HCC). We evaluated the analysis of circulating hypermethylated RASSF1A for detecting HCC and assessing its prognosis.
In module 1, we studied 63 pairs of HCC patients and age- and sex-matched chronic hepatitis B virus (HBV) carriers, as well as 50 healthy volunteers. In module 2, we studied 22 HCC patients with cancer detected through a surveillance program. The concentrations of circulating hypermethylated RASSF1A sequences were measured by real-time PCR after digestion with a methylation-sensitive restriction enzyme.
We detected hypermethylated RASSF1A sequences in the sera of 93% of HCC patients, 58% of HBV carriers, and 8% of the healthy volunteers. The median RASSF1A concentrations for the HCC patients and HBV carriers were 7.70 x 10(5) copies/L and 1.18 x 10(5) copies/L, respectively (P < 0.01). The detection of low concentrations in HBV carriers is consistent with previous findings that RASSF1A hypermethylation is an early event in HCC pathogenesis and can be found in premalignant liver tissues. Use of a marker cutoff value of 1 x 10(6) copies/L also identifies 50% of alpha-fetoprotein-negative HCC cases. Patients with higher RASSF1A concentrations at diagnosis or 1 year after tumor resection showed poorer disease-free survival (P < 0.01). For the HBV carriers who underwent HCC surveillance and subsequently developed HCC, the circulating concentration of RASSF1A increased significantly from the time of enrollment to cancer diagnosis (P = 0.014).
Detection and quantification of circulating methylated RASSF1A sequences are useful for HCC screening, detection, and prognostication.
Malignant mesothelioma (MM) is often complicated by thromboembolic episodes, with thrombomodulin (TM) playing a critical role in the anticoagulant process. Heterogeneous expression of TM has been observed in cancer, and low or no TM expression in cancer cells is associated with poor prognosis. In this study, we analyzed TM expression in biopsies of MM patients and compared them with normal mesothelial tissue. The role of DNA methylation-associated gene silencing in TM expression was investigated. To evaluate poly(ADP-ribose) polymerase-1 (PARP1) as responsible for gene promoter epigenetic modifications, nonmalignant mesothelial cells (Met-5A) and MM cells (H28) were silenced for PARP1 and the DNA methylation/acetylation-associated TM expression evaluated. A correlation between low TM expression and high level of TM promoter methylation was found in MM biopsies. Low expression of TM was restored in MM cells by their treatment with 5-aza-2'-deoxycytidine and, to a lesser extent, with trichostatin, whereas the epigenetic agents did not affect TM expression in Met-5A cells. Silencing of PARP1 resulted in a strong down-regulation of TM expression in Met-5A cells, while restoring TM expression in H28 cells. PARP1 silencing induced TM promoter methylation in Met-5A cells and demethylation in MM cells, and this was paralleled by corresponding changes in the DNA methyltransferase activity. We propose that methylation of the TM promoter is responsible for silencing of TM expression in MM tissue, a process that is regulated by PARP1.
Improved detection methods for diagnosis of malignant pleural mesothelioma (MPM) are essential for early and reliable detection as well as treatment. Since recent data point to abnormal levels of microRNAs (miRNAs) in tumors, we hypothesized that a profile of deregulated miRNAs may be a marker of MPM and that the levels of specific miRNAs may be used for monitoring its progress.
miRNAs isolated from fresh-frozen biopsies of MPM patients were tested for the expression of 88 types of miRNA involved in cancerogenesis. Most of the tested miRNAs were downregulated in the malignant tissues compared with the normal tissues. Of eight significantly downregulated, three miRNAs were assayed in cancerous tissue and adjacent non-cancerous tissue sample pairs collected from 27 formalin-fixed, paraffin-embedded MPM tissues by quantitative RT-PCR. Among the miRNAs tested, only miR-126 significantly remained downregulated in the malignant tissues. Furthermore, the performance of the selected miR-126 as biomarker was evaluated in serum samples of asbestos-exposed subjects and MPM patients and compared with controls. MiR-126 was not affected by asbestos exposure, whereas it was found strongly associated with VEGF serum levels. Levels of miR-126 in serum, and its levels in patients' serum in association with a specific marker of MPM, SMRPs, correlate with subjects at high risk to develop MPM.
We propose miR-126, in association with SMRPs, as a marker for early detection of MPM. The identification of tumor biomarkers used alone or, in particular, in combination could greatly facilitate the surveillance procedure for cohorts of subjects exposed to asbestos.
All forms of asbestos are now banned in 52 countries. Safer products have replaced many materials that once were made with it. Nonetheless, many countries still use, import, and export asbestos and asbestos-containing products, and in those that have banned other forms of asbestos, the so-called "controlled use" of chrysotile asbestos is often exempted from the ban. In fact, chrysotile has accounted for > 95% of all the asbestos used globally.
We examined and evaluated the literature used to support the exemption of chrysotile asbestos from the ban and how its exemption reflects the political and economic influence of the asbestos mining and manufacturing industry.
All forms of asbestos, including chrysotile, are proven human carcinogens. All forms cause malignant mesothelioma and lung and laryngeal cancers, and may cause ovarian, gastrointestinal, and other cancers. No exposure to asbestos is without risk. Illnesses and deaths from asbestos exposure are entirely preventable.
All countries of the world have an obligation to their citizens to join in the international endeavor to ban the mining, manufacture, and use of all forms of asbestos. An international ban is urgently needed. There is no medical or scientific basis to exempt chrysotile from the worldwide ban of asbestos.
Mechanisms of action of nonmutagenic carcinogens such as asbestos remain poorly characterized. As pleural mesothelioma is known to have limited numbers of genetic mutations, we aimed to characterize the relationships among gene-locus-specific methylation alterations, disease status, asbestos burden, and survival in this rapidly fatal asbestos-associated tumor. Methylation of 1505 CpG loci associated with 803 cancer-related genes were studied in 158 pleural mesotheliomas and 18 normal pleura. After false-discovery rate correction, 969 CpG loci were independently associated with disease status (Q < 0.05). Classifying samples based on CpG methylation profile with a mixture model approach, methylation classes discriminated tumor from normal pleura (permutation P < 0.0001). In a random forests classification, the overall misclassification error rate was 3.4%, with <1% (n = 1) of tumors misclassified as normal (P < 0.0001). Among tumors, methylation class membership was significantly associated with lung tissue asbestos body burden (P < 0.03), and significantly predicted survival (likelihood ratio P < 0.01). Consistent with prior work, asbestos burden was associated with an increased risk of death (hazard ratio, 1.4; 95% confidence interval, 1.1-1.8). Our results have shown that methylation profiles powerfully differentiate diseased pleura from nontumor pleura and that asbestos burden and methylation profiles are independent predictors of mesothelioma patient survival. We have added to the growing body of evidence that cellular epigenetic dysregulation is a critical mode of action for asbestos in the induction of pleural mesothelioma. Importantly, these findings hold great promise for using epigenetic profiling in the diagnosis and prognosis of human cancers.
Precise regulation of the formation, maintenance, and remodeling of the vasculature is required for normal development, tissue response to injury, and tumor progression. How specific microRNAs intersect with and modulate angiogenic signaling cascades is unknown. Here, we identified microRNAs that were enriched in endothelial cells derived from mouse embryonic stem (ES) cells and in developing mouse embryos. We found that miR-126 regulated the response of endothelial cells to VEGF. Additionally, knockdown of miR-126 in zebrafish resulted in loss of vascular integrity and hemorrhage during embryonic development. miR-126 functioned in part by directly repressing negative regulators of the VEGF pathway, including the Sprouty-related protein SPRED1 and phosphoinositol-3 kinase regulatory subunit 2 (PIK3R2/p85-beta). Increased expression of Spred1 or inhibition of VEGF signaling in zebrafish resulted in defects similar to miR-126 knockdown. These findings illustrate that a single miRNA can regulate vascular integrity and angiogenesis, providing a new target for modulating vascular formation and function.
Diagnosis of malignant pleural mesothelioma is a challenging issue. Potential markers in mesothelioma diagnosis include soluble mesothelin-related peptides (SMRPs) and osteopontin, but no subsequent validation has been published yet.
We prospectively evaluated SMRPs in serum and pleural effusion from patients with mesothelioma (n = 74), pleural metastasis of carcinomas (n = 35), or benign pleural lesions associated with asbestos exposure (n = 28), recruited when first suspected for mesothelioma.
Mean serum SMRP level was higher in patients with mesothelioma (2.05 +/- 2.57 nM/L [median +/- interquartile range]) than in patients with metastasis (1.02 +/- 1.79 nM/L) or benign lesions (0.55 +/- 0.59 nM/L). The area under the receiver operating characteristic curve (AUC) for serum SMRP was 0.872 for differentiating mesothelioma and benign lesions, cut-off = 0.93 nM/L (sensitivity = 80%, specificity = 82.6%). The AUC for serum SMRP differentiating metastasis and mesothelioma was 0.693, cut-off = 1.85 nM/L (sensitivity = 58.3%, specificity = 73.3%). SMRP values in pleural fluid were higher than in serum in all groups (mesothelioma: 46.1 +/- 83.2 nM/L; benign lesions: 6.4 +/- 11.1 nM/L; metastasis: 6.36 +/- 21.73 nM/L). The AUC for pleural SMRP-differentiating benign lesions and mesothelioma was 0.831, cut-off = 10.4 nM/L (sensitivity = 76.7%, specificity = 76.2%). The AUC for pleural SMRP-differentiating metastasis and mesothelioma was 0.793. Interpretation: We show that SMRPs may be a promising marker for mesothelioma diagnosis when measured either in serum or pleural fluid. The diagnostic value of SMRPs was similar in both types of samples, but pleural fluid SMRPs may better discriminate mesothelioma from pleural metastasis.
Methylation of tumor suppressor genes is among the most frequent alterations in patients with malignant pleural mesothelioma (MPM). The aim of this study was to analyze the promoter methylation status of four tumor suppressor genes, p15(INK4B), p16(INK4A), RASSF1A and NORE1A in MPM. Samples of 79 MPM patients were analyzed using a methylation-specific PCR method. Associations between methylation status, clinico-pathological parameters (including proliferation index) and overall survival (OS) were examined. The analysis documented methylation in 30 cases (38%). The methylation frequency for individual genes was 19% for p15(INK4B) (n=15), 11.4% for p16(INK4A) (n=9), 20.2% for RASSF1A (n=16) and 5.1% for Nore1A (n=4). In the whole series methylation was associated to an increased proliferation index (P=0.05). In patients treated with extrapleural pneumonectomy, methylated MPM showed a trend to a poorer OS in comparison to unmethylated cases (median OS 16 months vs. 35 months, P=0.06, HR=2.01, 95% CI 0.95-4.30). In the overall population, methylation did not correlate to patient outcome but a trend to an improved survival was detectable in ummethylated MPM treated with extrapleural pneumonectomy. This result suggests the need to select homogeneously treated and staged patients with MPM to address whether their methylation profile may impact on patient's survival.
Abstract In the past 25 years, a majority of cancer studies have focused on examining functional consequences of activating and/or inactivating mutations in critical genes implicated in cell cycle control. These studies have taught us a great deal about the functions of oncogenes and tumor suppressor genes and the signaling pathways regulating cell proliferation and/or cell death. However, such studies have largely ignored the fact that cancers are heterogeneous cellular entities whose growth is dependent upon reciprocal interactions between genetically altered "initiated" cells and the dynamic microenvironment in which they live. This review highlights the aspects of cancer development that, like organogenesis during embryonic development and tissue repair in adult mammals, are regulated by interactions between epithelial cells, activated stromal cells, and soluble and insoluble components of the extracellular matrix.
A search for general regulators of cancer metastasis has yielded a set of microRNAs for which expression is specifically lost as human breast cancer cells develop metastatic potential. Here we show that restoring the expression of these microRNAs in malignant cells suppresses lung and bone metastasis by human cancer cells in vivo. Of these microRNAs, miR-126 restoration reduces overall tumour growth and proliferation, whereas miR-335 inhibits metastatic cell invasion. miR-335 regulates a set of genes whose collective expression in a large cohort of human tumours is associated with risk of distal metastasis. miR-335 suppresses metastasis and migration through targeting of the progenitor cell transcription factor SOX4 and extracellular matrix component tenascin C. Expression of miR-126 and miR-335 is lost in the majority of primary breast tumours from patients who relapse, and the loss of expression of either microRNA is associated with poor distal metastasis-free survival. miR-335 and miR-126 are thus identified as metastasis suppressor microRNAs in human breast cancer.
Improved detection methods for diagnosis of asymptomatic malignant mesothelioma (MM) are essential for an early and reliable detection and treatment of this type of neoplastic disease. Thus, focus has been on finding tumor markers in the blood that can be used for noninvasive detection of MM. Ninety-four asbestos-exposed subjects defined at high risk, 22 patients with MM, and 54 healthy subjects were recruited for evaluation of the clinical significance of 8-hydroxy-2'-deoxyguanosine (80HdG) in WBCs and plasma concentrations of soluble mesothelin-related peptides (SMRPs), angiogenic factors [platelet-derived growth factor, hepatocyte growth factor, basic fibroblast growth factor, and vascular endothelial growth factor 0 (VEGF beta)], and matrix proteases [matrix metalloproteinase (MMP) 2, MMP9, tissue inhibitor of metalloproteinase (TIMP) 1, and TIMP2] for potential early detection of MM. The area under receiver operating characteristic (ROC) curves indicate that 80HdG levels can discriminate asbestos- exposed subjects from healthy controls but not from MM patients. Significant area under ROC curve values were found for SMRPs, discriminating asbestos-exposed subjects from MM patients but not from healthy controls. Except for platelet-derived growth factor beta, the hepatocyte growth factor, basic fibroblast growth factor, and VEGF can significantly differentiate high-risk individuals from healthy control and cancer groups. No diagnostic value was observed for MMP2, MMP9, TIMP1, and TIMP2. In addition to the diagnostic performance defined by the ROC analysis, the sensitivity and specificity results of markers with clinical significance were calculated at defined cutoffs. The combination of 80HdG, VEGF beta, and SMRPs best distinguished the individual groups, suggesting a potential indicator of early and advanced MM cancers. The combination of blood biomarkers and radiographic findings could be used to stratify the risk of mesothelioma in asbestos-exposed populations.
Malignant mesothelioma (MM) is a highly aggressive tumor associated with asbestos exposure. The identification of a marker specific for MM may be of considerable value for the early detection of this tumor and may be used in particular to screen groups with a history of asbestos exposure. The aim of this study was to evaluate serum soluble mesothelin-related peptide (SMRP) levels as a diagnostic marker for MM and investigate whether its diagnostic value is enhanced by combination with other biomarkers. Serum SMRP levels were measured using a quantitative enzyme-linked immunosorbent assay in 96 patients with MM, 55 patients with lung cancer and 39 individuals with a history of asbestos exposure. Receiver operating characteristic curves were constructed for performance evaluation. Stepwise logistic regression analysis was used to select marker combinations (MCs). Serum SMRP levels in patients with MM were significantly higher compared to those in the other groups (P<0.001). The sensitivity of SMRP levels in diagnosing MM was 56% and its specificity for MM vs. lung cancer and individuals with asbestos exposure was 87 and 92%, respectively. The area under the curve (AUC) was 0.76 [95% confidence interval (CI): 0.68-0.83] for the differentiation between MM and lung cancer and 0.78 (95% CI: 0.71-0.86) for the differentiation between MM and individuals with asbestos exposure. For the MC of presence of effusion, SMRP and carcinoembryonic antigen (CEA) levels, the AUC for the differentiation between MM and lung cancer (0.92; 95% CI: 0.88-0.97) and the differentiation between MM and individuals with asbestos exposure (0.93; 95% CI: 0.87-1.0) was significantly higher compared to that for SMRP alone (P=0.0001 and 0.0058, respectively). While the specificity of this MC was comparable to SMRP alone, its sensitivity was ∼20% higher compared to that of SMRP alone. Therefore, combining SMRP and CEA improves the diagnostic performance of SMRP alone. A combination of serum biomarkers, including SMRP, may facilitate the non-invasive diagnosis of MM.
Background/Aim: In the diagnosis of malignant mesothelioma (MM) there still is a lack of specific and sensitive screening biomarkers: this study examined the discriminatory power of a panel of serum/plasma biomarkers.
The study involved four groups: (a) individuals previously exposed to asbestos with asbestosis; (b) patients with MM; (c) patients with non-small cell lung cancer; and (d) controls without any evidence of malignancy. The concentrations of mesothelin, chitinase-3-like-1 (YKL-40), vascular endothelial growth factor (VEGF), endothelin-1, interleukin-8 (IL-8) and fibulin-3 in the serum of patients were determined.
Patients with MM had significantly higher serum levels of mesothelin (p<0.001), YKL-40 (p<0.001), IL-8 (p<0.001) and VEGF (p<0.01) than controls. The cut-off point for MM was 1.26 nM for mesothelin alone, and 167 pg/ml for YKL-40 alone; the presence of both markers above these cut-off levels improved diagnostic specificity.
The addition of YKL-40 may improve the specificity of mesothelin measurements alone for detecting patients with MM.
microRNAs (miRNAs) have been reported to play a crucial role in regulating a variety of genes pivotal for tumor metastasis. miR-126 is well known as one of the angiogenesis regulatory miRNAs. Recent studies have reported controversial roles of miR-126 in tumor progression. In this study, we sought to investigate the potential roles of miR-126 in colorectal cancer (CRC). By real-time PCR, miR-126 was shown to be downregulated in primary CRC tissues and cell lines. Restoration of miR-126 in CRC cells inhibited cell growth, migration and invasion. Using both in silico prediction and immunoblotting, we found that vascular endothelial growth factor (VEGF) was a target of miR-126. The interaction of miR-126 on the 3'UTR of VEGF mRNA was validated by luciferase reporter assay. Mechanistically, we found that the silencing of miR-126 was induced by promoter methyl-ation of its host gene, EGFL7. Treatment with 5-aza-CdR restored miR-126 expression and thereby led to a decline in VEGF expression. Functionally, due to suppression of VEGF, enhanced miR-126 expression inhibited tumor neovasculature triggered by CRC cells. In conclusion, our findings suggest that DNA methylation-induced silencing of miR-126 contributes, at least in part, to tumor invasion and angiogenesis in CRC, through upregulation of VEGF expression. miR-126 may be a potential target for the therapeutic strategy against CRC.
: Soluble mesothelin-related peptides (SMRP) have been reported as potential markers for the diagnosis of malignant pleural mesothelioma (MPM). We wondered, whether a combination with a carcinoembryonic antigen (CEA) test might improve the relatively low diagnostic yield of the SMRP test.
: In a retrospective study, SMRP (mesothelin) and CEA serum concentrations were measured, using commercially available kits, in 93 previously untreated MPM patients, 75 patients with benign asbestos disease, and 139 patients suffering from lung cancer (LC).
: The differentiation between MPM, LC, and benign asbestos disease could be improved by applying the ratio mesothelin/CEA. Whereas CEA expression was found to be low in MPM, most LC patients had elevated CEA serum levels. The area under curve (AUC) of the receiver operator characteristics curve for mesothelin alone was found to be only 0.708. For mesothelin/CEA the AUC of the receiver operator characteristics curve increased to 0.978. The sensitivity was 93% (69%) at 95% (100%) specificity for the differentiation between MPM and LC. Comparison of MPM and benign asbestos disease showed that the AUC was 0.887 and the sensitivity 56% (47%) at 95% (100%) specificity. In contrast, the AUC for the mesothelin test alone was only 0.715, and for the CEA test alone it was 0.16. An average increment in sensitivity of 38% (range, 16%-63%) could be achieved by the quotient mesothelin/CEA compared with the sensitivity of mesothelin alone.
: The diagnostic yield of the mesothelin test can be considerably improved when combined with a CEA test with regard to the differential diagnosis between MPM and LC and between MPM and benign asbestos disease.
A previous study demonstrated that miR-126 expression was significantly downregulated in highly metastatic colon cancer cells. This study was to investigate the biological function of miR-126 and its regulation of target genes in colon cancer cells. Quantitative PCR was used to detect miR-126 expression in colon cancer SW480 and SW620 cells. MTT assay was to measure the changed cell viability after miR-126 mimics transfection. Wound healing and Transwell migration and invasion assays measured capacity of tumor cell migration and invasion of SW480 and SW620 cells after miR-126 transfection. Luciferase reporter assay and Western blot were used to assess both transcriptional and expression levels of one of the miR-126 target genes (i.e., CXCR4). Levels of miR-126 expression were lower in colon cancer SW480 and SW620 cells than in the adjacent normal epithelial tissues (P < 0.05). Transfection of miR-126 mimics significantly reduced colon cancer cell viability compared to NC cells (P < 0.05). The wound healing and Transwell migration and invasion assays showed that miR-126 mimics inhibited SW480 and SW620 cell migration and invasion capacity. Bioinformatics predicted that CXCR4 is one of the miR-126 target genes. Indeed, luciferase reporter assay and Western blot confirmed that CXCR4 is a miR-126 target gene. Expression of miR-126 inhibited colon cancer cell viability and reduced tumor cell migration and invasion capacity by its negative regulation of CXCR4 expression.
Disturbance of miRNA expression may play a key role in the initiation and progression of colorectal cancer (CRC). CRC should be viewed as a heterogeneous disease, but previous studies have only screened dysregulated miRNAs in CRC from a panel of 96, 145, 287 and 455 miRNAs, respectively. It is necessary to identify new aberrantly expressed miRNAs in rectal cancer. In this study tissue samples were derived from patients undergoing a surgical procedure to remove a portion of cancers. The expression profile of 904 miRNAs was analyzed using a miRCURY™ LNA Array from 6-paired rectal cancers and normal tissues. The expression levels of 4 miRNAs were compared by real-time PCR between colon and rectal cancer, and also the expression levels of metastatic miRNAs in different stages of rectal cancer were analyzed. We found that 67 miRNA precursors are upregulated in rectal cancer (p<0.05) and 21 of those have never been reported in colorectal cancer (CRC); 39 miRNA precursors are downregulated (p<0.05) and 24 novel dysregulated miRNAs were identified in rectal cancer. miR-31, miR-126 and miR-143 are differentially expressed between colon cancer and rectal cancer. Here, we report an miRNA profile of rectal cancer, and we identified differential expression patterns of miRNAs between rectal and colon cancers. This novel information may suggest the potential roles of these miRNAs in the diagnosis of rectal cancer.
Aim of this study was to evaluate the accuracy and precision of the detection of individual miRNA as clinical biomarkers in the serum.
miRNA-126 was quantified in serum using endogenous and exogenous controls for normalization and the accuracy and precision of the method evaluated. The diagnostic value of serum miRNA-126 was evaluated in malignant mesothelioma (MM) and non-small-cell lung cancer (NSCLC) patients using both relative and absolute qRT-PCR methods.
The use of endogenous invariant and exogenous synthetic controls as well sample dilution markedly improves the accuracy and precision of the assay. The inter- and intra-assay analyses revealed that relative qRT-PCR is a more reliable method. Circulating miR-126 detected in the serum by relative qRT-PCRs was found low-expressed in both malignancies, significantly differentiated MM patients from healthy controls and NSCLC from MM, but do not discriminate NSCLC patients from control subjects. Kaplan-Meier analysis revealed that low level of circulating miR-126 in MM patients was strongly associated with worse prognosis.
We propose that this approach can be adopted for accurate analysis of other suitable circulating miRNA markers of different types of cancer.
Epidemiological studies have shown that mortality from malignant mesothelioma (MM) and lung cancer have increased with increasing cumulative exposure to asbestos. To investigate whether tumour-related biomarkers can contribute towards the evaluation of the carcinogenic risk in populations exposed to asbestos, the DNA adduct 8-hydroxy-2'-deoxyguanosine (80HdG), interleukine-6 (IL-6), platelet-derived growth factor (PDGF-BB), hepatocyte growth factor (HGF), basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGFbeta) and soluble mesothelin-related peptides (SMRPs) were analysed in a cohort of workers differently exposed to asbestos fibres at the workplace. To document biomarker levels in an unexposed population, 54 age-matched subjects were enrolled. A total of 119 subjects with a history of occupational exposure to asbestos underwent clinical examination and were interviewed by trained personnel, responding to a detailed questionnaire related to duration of asbestos exposure, smoking, and occupational task. According to the occupational tasks, asbestos-exposed subjects were analysed for their asbestos cumulative dose and the association with the biomarkers was evaluated. Among the occupational groups, maintenance workers, pipe fitters and electricians were exposed to a higher cumulative dose of asbestos fibres. Exposure to asbestos significantly increased the steady-state content of 80HdG in DNA. Elevated levels of 80HdG and IL-6 best reflected a high level of SMRPs, which is related to cell transformation. Subjects heavily exposed to asbestos [> 60(ff/cm3) x years] showed also a higher level of angiogenic factors. A combination of angiogenic biomarkers with a specific mesothelioma-biomarker such as SMRPs could be used for close surveillance of workers with a history of asbestos exposure.
Malignant pleural mesothelioma (MPM) is a lethal tumor related to asbestos exposure. At present, the only instruments for screening and diagnosis are based on radiological tests, posing evident economic and radio-protectionist problems. Some authors are evaluating biological indicators, such as plasma osteopontin (pOPN) and serum soluble mesothelin-related peptides (SMRP). This study aimed to evaluate whether a combination of these two markers could increase sensitivity and specificity in diagnosis of epithelioid MPM.
We enrolled 93 healthy subjects, 111 individuals with benign respiratory disease (BRD), and 31 patients with MPM, histologically and/or cytologically confirmed. SMRP and pOPN levels were determined using commercially available enzyme-linked immunosorbent assay kits. Though a logistic regression analysis, SMRP and pOPN were combined and translated into a new index, called "combined risk index."
Differences in both SMRP and pOPN mean values between epithelial MPM patients and healthy subjects or BRD patients were statistically significant (p < 0.0001), whereas there was no difference in SMRP and pOPN mean values between healthy subjects and BRD patients. The performance in MPM diagnosis resulted improved by the combination of the two markers. The results of our study should be confirmed by a larger scale and, possibly, a multicenter study, which could better take into consideration the influence of some possible confounding factors such as glomerular filtration rate and other blood parameters.
We combined SMRP and pOPN dosages to increase diagnostic accuracy. This study showed for the first time that combined SMRP and pOPN measurements can increase both sensitivity and specificity in terms of combined risk index.
Tumor blood vessels are heterogeneous, of at least six distinct types, are induced primarily by vascular endothelial growth factor-A (VEGF-A), and provide a potentially useful therapeutic target. Breast cancer is characterized by changes in the microenvironment that result in altered tensional homeostasis. Also, breast cancers arise as the result of epigenetic as well as genetic changes. Tumor blood vessel pericytes result, in part, from bone marrow precursor cells, and VEGF is a negative regulator of glioblastoma tumor cell invasion.
Endothelial cells are the key components of vascular intima and play pivotal roles in vasculogenesis, angiogenesis, and tumor growth. Using Northern blot and real-time PCR, we confirmed that miR-126 and its host gene EGF-like domain 7 (EGFL7) were widely expressed in rat tissues but strictly expressed in endothelial cells. In mammals, miR-126 gene is embedded in intron7 of EGFL7. To explore the biogenesis of miR-126, plasmid EGFL7(126)-pEGFPc1 containing segment of exon7-intron7-exon8 of EGFL7 was constructed and expressed in 293T. Expression of spliced exon7-8 and excised mature miR-126 was detected by PCR and Northern blot. Knocking-down of endothelial endogenous miR-126 did not affect EGFL7 expression at mRNA or protein level. To investigate the possible roles of miR-126, PicTar, miRBase, miRanda, Bibiserv, and Targetscan were used to screen the targets. VEGFA and PIK3R2 were confirmed as the targets of miR-126 by luciferase reporter assay and Western blot. Interestingly, Northern blot and western blot showed that miR-126 was down-regulated in breast tumors where the VEGF/PI3K/AKT signaling pathway was activated. Introduction of miR-126 mimics into MCF-7 could effectively decrease VEGF/PI3K/AKT signaling activity. In summary, miR-126 was strictly expressed in endothelial cells and excised from EGFL7 pre-mRNA without affecting splicing and expression of its host gene. In addition, miR-126 could target both VEGFA and PIK3R2, and its expression was decreased in human breast cancer, implying that miR-126 may play a role in tumor genesis and growth by regulating the VEGF/PI3K/AKT signaling pathway.
MicroRNAs have emerged as important gene regulators and are recognised as key players in carcinogenesis. In the present study, we show that miR-126 was significantly down-regulated in gastric cancer tissues compared with matched normal tissues and was associated with clinicopathological features, including tumour size, lymph node metastasis, local invasion and tumour-node-metastasis (TNM) stage. Ectopic expression of miR-126 in SGC-7901 gastric cancer cells potently inhibited cell growth by inducing cell cycle arrest in G0/G1 phase, migration and invasion in vitro as well as tumorigenicity and metastasis in vivo. Mechanistically, we identified the adaptor protein Crk as a target of miR-126. Taken together, our results suggest that miR-126 may function as a tumour suppressor in gastric cancer, with Crk as a direct target.
Thrombomodulin (TM) plays a role in coagulation, inflammation, and cell adhesion. Reduction of TM expression plays an important role in the tumor metastatic process; however, insufficient information is available regarding the expression of TM in nonsmall cell lung cancer (NSCLC). Sixty NSCLC patients who underwent surgery were reviewed for TM expression and multiple variables were assessed by univariate and multivariate analyses. The expression level of TM and its metastatic ability were examined in vitro using the human NSCLC A549 cell line. TM expression in NSCLC was significantly correlated with survival; the 5-yr survival rates of patients with high and low TM expression were 23% and 18% (P < 0.01), respectively. Distribution of TM was detected predominantly in the normal lung tissue compared with lung cancer tissue. Western blot analysis showed, on average, decreased expression levels of TM protein in the lung cancer tissues of patients with NSCLC. An in vitro study also showed that overexpression of TM can inhibit the invasiveness and migration ability of the A549 cell line, whereas silencing of TM significantly enhanced these processes. This inhibition of cellular migration by overexpression of TM was significantly prevented by the selective inhibitors of PI3K and Akt, but not by MAPK inhibitors. This study demonstrates that a decrease in TM expression may be an indicator in the prognosis of NSCLC patients and provides new insights into the molecular mechanisms of TM in the metastasis of NSCLC.
Malignant pleural mesothelioma (MPM) is a fatal thoracic malignancy, the epigenetics of which are poorly defined. We performed high-throughput methylation analysis covering 6,157 CpG islands in 20 MPMs and 20 lung adenocarcinomas. Newly identified genes were further analyzed in 50 MPMs and 56 adenocarcinomas via quantitative methylation-specific PCR. Targets of histone H3 lysine 27 trimethylation (H3K27me3) and genetic alterations were also assessed in MPM cells by chromatin immunoprecipitation arrays and comparative genomic hybridization arrays. An average of 387 genes (6.3%) and 544 genes (8.8%) were hypermethylated in MPM and adenocarcinoma, respectively. Hierarchical cluster analysis showed that the two malignancies have characteristic DNA methylation patterns, likely a result of different pathologic processes. In MPM, a separate subset of genes was silenced by H3K27me3 and could be reactivated by treatment with a histone deacetylase inhibitor alone. Integrated analysis of these epigenetic and genetic alterations revealed that only 11% of heterozygously deleted genes were affected by DNA methylation and/or H3K27me3 in MPMs. Among the DNA hypermethylated genes, three (TMEM30B, KAZALD1, and MAPK13) were specifically methylated only in MPM and could serve as potential diagnostic markers. Interestingly, a subset of MPM cases (4 cases, 20%) had very low levels of DNA methylation and substantially longer survival, suggesting that the epigenetic alterations are one mechanism affecting progression of this disease. Our findings show a characteristic epigenetic profile of MPM and uncover multiple distinct epigenetic abnormalities that lead to the silencing of tumor suppressor genes in MPM and could serve as diagnostic or prognostic targets.
Serum mesothelin, also known as soluble mesothelin-related protein (SMRP), reportedly shows increased levels in epithelial-type malignant pleural mesothelioma, but sometimes also arrives at high values in healthy asbestos-exposed subjects.
This study aimed to investigate whether single nucleotide polymorphisms in the 3'untranslated region (3'UTR) of the mesothelin-encoded gene (MSLN) are associated with the SMRP levels measured in serum.
The 3'UTR of the mesothelin gene was genotyped in 59 healthy asbestos-exposed subjects, selected on the basis of their SMRP levels. Direct sequencing did not show any new polymorphism, but enabled us to genotype two known SNPs (rs1057147, rs57272256). Differences in the mean values of SMRP in wild-type and variant heterozygote groups were calculated.
High levels of SMRP in healthy asbestos-exposed subjects were significantly associated with polymorphism rs1057147 (G<A). Regarding rs57272256, there was no statistically significant difference between wild-type and heterozygote groups. Our study suggests that rs1057147 polymorphism can affect mesothelin expression. Although these data need to be confirmed with a larger number of cases, this study warrants further research in order to better understand the relationship between mesothelin polymorphisms and SMRP.
Studies have shown that aberrant expression of miRNAs is involved in the initiation and progression of cancer, and several miRNAs have been characterized as tumor suppressors or oncogenes. Restoring the expression of tumor suppressor genes by epigenetic therapy has great potential in cancer treatment and it has been shown that some miRNAs can be directly regulated from their own promoters by epigenetic alterations in cancer cells. However, the majority of miRNAs are located within intronic regions of transcription units and it was unclear if intronic miRNAs can also be epigenetically regulated. Here we show that the tumor suppressor miR-126, which is located within an intron of the EGFL7 gene, is downregulated in cancer cell lines and in primary bladder and prostate tumors. Mature miR-126 can be generated from three different transcripts of EGFL7 with each one having its own promoter. Interestingly, miR-126 and one of the transcripts of EGFL7 that has a CpG island promoter are concomitantly upregulated in cancer cell lines by inhibitors of DNA methylation and histone deacetylation. These findings suggest that epigenetic changes can control the expression of tumor suppressor intronic miRNAs by directly controlling their host genes. Thus, epigenetic therapy not only directly activates miRNAs from their own promoters, but also activates intronic miRNAs together with their host genes. This reveals an additional mechanism and anticancer effect of epigenetic therapy.
miRNAs are a family of approximately 22-nuleotide-long noncoding RNAs involved in the formation and progress of tumors. Since traditional methods for the detection of miRNAs expression have many disadvantages, we developed a simple method called polyA RT PCR. With this method, we detected a series of miRNAs and found that mir-126 is one of the miRNAs underexpressed in breast cancer cells. Flow cytometry analysis showed that mir-126 inhibited cell cycle progression from G1/G0 to S. Further studies revealed that mir-126 targeted IRS-1 at the translation level. Knocking down of IRS-1 suppresses cell growth in HEK293 and breast cancer cell MCF-7, which recapitulates the effects of mir-126. In conclusion, we developed a simple method for high-throughput screening of miRNAs and found that mir-126, a cell growth suppressor, targets IRS-1.
Endothelial cells play essential roles in maintenance of vascular integrity, angiogenesis, and wound repair. We show that an endothelial cell-restricted microRNA (miR-126) mediates developmental angiogenesis in vivo. Targeted deletion of miR-126 in mice causes leaky vessels, hemorrhaging, and partial embryonic lethality, due to a loss of vascular integrity and defects in endothelial cell proliferation, migration, and angiogenesis. The subset of mutant animals that survives displays defective cardiac neovascularization following myocardial infarction. The vascular abnormalities of miR-126 mutant mice resemble the consequences of diminished signaling by angiogenic growth factors, such as VEGF and FGF. Accordingly, miR-126 enhances the proangiogenic actions of VEGF and FGF and promotes blood vessel formation by repressing the expression of Spred-1, an intracellular inhibitor of angiogenic signaling. These findings have important therapeutic implications for a variety of disorders involving abnormal angiogenesis and vascular leakage.
Patients with malignant pleural mesothelioma, a rapidly progressing malignancy with a median survival time of 6 to 9 months, have previously responded poorly to chemotherapy. We conducted a phase III trial to determine whether treatment with pemetrexed and cisplatin results in survival time superior to that achieved with cisplatin alone.
Chemotherapy-naive patients who were not eligible for curative surgery were randomly assigned to receive pemetrexed 500 mg/m2 and cisplatin 75 mg/m2 on day 1, or cisplatin 75 mg/m2 on day 1. Both regimens were given intravenously every 21 days.
A total of 456 patients were assigned: 226 received pemetrexed and cisplatin, 222 received cisplatin alone, and eight never received therapy. Median survival time in the pemetrexed/cisplatin arm was 12.1 months versus 9.3 months in the control arm (P =.020, two-sided log-rank test). The hazard ratio for death of patients in the pemetrexed/cisplatin arm versus those in the control arm was 0.77. Median time to progression was significantly longer in the pemetrexed/cisplatin arm: 5.7 months versus 3.9 months (P =.001). Response rates were 41.3% in the pemetrexed/cisplatin arm versus 16.7% in the control arm (P <.0001). After 117 patients had enrolled, folic acid and vitamin B12 were added to reduce toxicity, resulting in a significant reduction in toxicities in the pemetrexed/cisplatin arm.
Treatment with pemetrexed plus cisplatin and vitamin supplementation resulted in superior survival time, time to progression, and response rates compared with treatment with cisplatin alone in patients with malignant pleural mesothelioma. Addition of folic acid and vitamin B12 significantly reduced toxicity without adversely affecting survival time.
Since its discovery as a critical cofactor in the initiation of the protein C (PC) anticoagulant pathway [1,2], biochemical and structural investigations, combined with in vivo analyses of genetically engineered mice have revealed new, and in part PC- and thrombin-independent aspects of thrombomodulin (TM) function in fibrinolysis and inflammation, and in embryogenesis. This review summarizes more recent structural and functional investigations of TM, gives an overview of the association of TM gene polymorphisms with human disease, and provides a synopsis of what is know about TM function in disease states of thrombosis, stroke, arteriosclerosis, and cancer. Newly emerging aspects of TM function in inflammation and embryogenesis are presented and discussed in detail.
Mesothelioma is a highly aggressive tumour for which there are no reliable serum tumour markers. Identification of such a marker would be useful in diagnosis of mesothelioma and for monitoring responses to treatment and screening at-risk individuals.
We assayed serum concentrations of soluble mesothelin-related proteins (SMR) using a double determinant (sandwich) ELISA in a blinded study of serum samples from 44 patients with histologically proven mesothelioma; 68 matched healthy controls, 40 of whom had been exposed to asbestos; and 160 patients with other inflammatory or malignant lung and pleural diseases.
37 (84%) of 44 patients with mesothelioma had raised concentrations of SMR at a serum dilution of 1/80, compared with three (2%) of 160 patients with other cancers or other inflammatory lung or pleural diseases, and with none of 28 controls who had not been exposed to asbestos. SMR concentrations correlated with tumour size and increased during tumour progression. Seven of the 40 asbestos-exposed individuals had increased serum concentrations of SMR; three of those seven developed mesothelioma and one developed lung carcinoma within 1-5 years. None of the 33 asbestos-exposed participants whose serum samples had normal concentrations of SMR and who were followed up over 8 years developed mesothelioma.
Determination of SMR in serum could be a useful marker for diagnosis of mesothelioma and to monitor disease progression. It might also prove helpful for screening asbestos-exposed individuals for early evidence of mesothelioma.
The p57KIP2 gene belongs to the Cip/Kip family of CDK inhibitors and has been demonstrated to be a tumor suppressor gene, being inactivated in various types of human cancers. We analyzed the methylation and expression status of p57KIP2 in lung and breast cancers, and in malignant mesotheliomas (MMs). The promoter region of p57KIP2 was determined by methylation-specific PCR (MSP) in samples of lung and breast cancer, and of MM. The expression of the gene in the cell lines was determined by RT-PCR and correlated with the methylation status. Aberrant methylation was detected by MSP in 9 of 27 (33%) and 25 of 78 (32%) lung cancer cell lines and tumors, respectively, 11 of 18 (61%) and 17 of 38 (45%) breast cancer cell lines and tumors, respectively, and 1 of 25 (4%) MM tumors. DNA methylation was detected but rarely in the corresponding non-malignant tissues. In addition, the gene expression was restored in the methylated cell lines following 5-aza-2'-deoxycytidine treatment, confirming that the methylation was indeed responsible for the gene down-regulation. We also examined the relationship between the p57KIP2 methylation status and the clinicopathological features of the primary tumors, and found that there was no relationship between the p57KIP2 methylation status and any of the examined clinicopathological features. In summary, our results demonstrate that p57KIP2 methylation associated with the gene down-regulation is frequently present in lung and breast cancers and plays an important role at the molecular level in the pathogenesis of these cancers.
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