James G Herman

University of Pittsburgh, Pittsburgh, Pennsylvania, United States

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Publications (343)3273.25 Total impact

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    ABSTRACT: Naked cuticle homolog 2 (NKD2) has been reported to antagonize Wnt signaling in zebrafish, mouse and mammals. The aim of this study is to investigate the epigenetic changes and mechanisms of NKD2 in human breast cancer development. Six breast cancer cell lines (MCF-7, ZR75-1, MDA-MB-468, MDA-MB-231, T47D and BT474) and 68 cases of primary human breast cancer were studied using methylation specific PCR, immunohistochemistry, western blot, flow cytometry techniques and a xenograft mouse model. The expression of NKD1 and NKD2 was regulated by promoter region methylation in breast cancer cells. No NKD1 methylation was found in primary human breast cancer. NKD2 was methylated in 51.4% (35/68) of human primary breast cancer samples. NKD2 methylation was significantly associated with reduction of NKD2 expression, and tumor stage (p < 0.05). NKD2 suppressed breast cancer cell proliferation both in vitro and in vivo. NKD2 induced G1/S arrest and inhibited Wnt signaling in breast cancer cells. In conclusion, NKD2 is frequently methylated in human breast cancer, and the expression of NKD2 is regulated by promoter region methylation. NKD2 suppresses breast cancer proliferation by inhibiting Wnt signaling.
    Oncotarget 06/2015; · 6.63 Impact Factor
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    ABSTRACT: Neurofilament heavy polypeptide (NEFH) has recently been identified as a candidate DNA hypermethylated gene within the functional breast cancer hypermethylome. NEFH exists in a complex with neurofilament medium polypeptide (NEFM) and neurofilament light polypeptide (NEFL) to form neurofilaments, which are structural components of the cytoskeleton in mature neurons. Recent studies reported the deregulation of these proteins in several malignancies, suggesting that neurofilaments may have a role in other cell types as well. Using a comprehensive approach, we studied the epigenetic inactivation of neurofilament genes in breast cancer and the functional significance of this event. We report that DNA methylation-associated silencing of NEFH, NEFL, and NEFM in breast cancer is frequent, cancer-specific, and correlates with clinical features of disease progression. DNA methylation-mediated inactivation of these genes occurs also in multiple other cancer histologies including pancreas, gastric, and colon. Restoration of NEFH function, the major subunit of the neurofilament complex, reduces proliferation and growth of breast cancer cells and arrests them in Go/G1 phase of the cell cycle along with a reduction in migration and invasion. These findings suggest that DNA methylation-mediated silencing of the neurofilament genes NEFH, NEFM, and NEFL are frequent events that may contribute to the progression of breast cancer and possibly other malignancies.
    Epigenetics: official journal of the DNA Methylation Society 05/2015; DOI:10.1080/15592294.2015.1050173 · 5.11 Impact Factor
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    ABSTRACT: Hepatocellular carcinoma (HCC) is one of the most common malignances and the second leading cause of cancer related death worldwide. RASSF10 is located on chromosome 11p15.2, a region that shows frequent loss of heterozygosity (LOH) in several cancer types. Our previous study found that RASSF10 suppresses colorectal cancer growth by activating P53 signaling. To explore the epigenetic changes and the mechanism of RASSF10 in human HCC, 69 cases of primary HCC, twenty cases of normal liver tissue samples and 17 HCC cell lines were involved in this study. We found that RASSF10 was methylated in 82.6% (57/69) of human primary HCC and methylation of RASSF10 was significantly associated with tumor size (P < 0.05) and TNM stage (P < 0.05). The expression of RASSF10 was regulated by promoter region methylation. Restoration of RASSF10 expression suppressed cell proliferation, induced apoptosis and G2/M phase arrest, as well as sensitized cells to docetaxel and activated P53 signaling in HepG2 and QGY7703 cells. In conclusion, we demonstrated that RASSF10 is frequently methylated in human HCC and its methylation is a potential docetaxel resistant marker. Our data also indicate that RASSF10 suppresses human HCC growth by activating P53 signaling.
    Genes & cancer 05/2015; 6(5-6):231-40.
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    ABSTRACT: In this era of molecular diagnostics, prediction of clear-cell renal cell cancer (ccRCC) survival requires optimization, as current prognostic markers fail to determine individual patient outcome. Epigenetic events are promising molecular markers. Promoter CpG island methylation of cysteine dioxygenase type 1 (CDO1), which was identified as prognostic marker for breast cancer, is studied as potential marker for ccRCC survival. We collected primary tissues of 365 ccRCC cases identified within the prospective Netherlands Cohort Study (NLCS). In this population-based series, CDO1 promoter methylation was observed in 124 of 324 (38.3%) patients with successful methylation-specific PCR analysis. Kaplan-Meier curves and Wilcoxon tests were used to evaluate 10-year ccRCC-specific survival. Cox regression analysis was used to obtain crude and multivariate hazard ratios (HR) and 95% confidence intervals (CI). The relative prognostic value of multivariate models with and without CDO1 promoter methylation was compared using Likelihood-Ratio tests. Patients with CDO1 promoter methylation have a significantly poorer survival than those without (Wilcoxon P=0.006). Differences in survival were independent of other prognostic factors, including age and sex (HR(95%CI)=1.66(1.12-2.45)) and TNM stage, tumor size and Fuhrman grade (HR(95%CI)=1.89(1.25-2.85)). Multivariate models performed better with than without CDO1 promoter methylation status (Likelihood-Ratio P=0.003). Survival curves were validated in an independent series of 280 ccRCC cases from the Cancer Genome Atlas (TCGA; Wilcoxon P<0.001). CDO1 promoter methylation may not substitute common prognostic makers to predict ccRCC survival, but offers additional, relevant prognostic information, indicating that it could be a novel molecular marker to determine ccRCC prognosis. Copyright © 2015, American Association for Cancer Research.
    Clinical Cancer Research 04/2015; DOI:10.1158/1078-0432.CCR-14-2049 · 8.19 Impact Factor
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    ABSTRACT: BCL6B is a potential tumor suppressor in human gastric cancer, but the regulation and mechanism of BCL6B in human hepatocellular carcinogenesis remain unclear. This study is to explore the epigenetic change and mechanism of BCL6B in human hepatocellular carcinoma (HCC). Nineteen hepatic cancer cell lines, 50 cases of adjacent tissue and 149 cases of HCC samples were employed. BCL6B is methylated in 100% (19/19) of human HCC cell lines, 40.0% (20/50) of adjacent tissue samples and 86.6% (129/149) of primary cancer samples. Methylation of BCL6B is associated with HBV positive (p < 0.05). But no association was found with age, sex, tumor size, differentiation, TNM stage, recurrence and survival. Loss of BCL6B expression was found in 19 of completely methylated HCC cell lines. BCL6B was re-expressed after 5-aza-2'-deoxycytidine treatment. Restoration of BCL6B expression suppressed cell proliferation, induced apoptosis and G1/S arrest in HCC cells. The expression of EGR1, a key component of p53 signaling, was increased after re-expression BCL6B in HCC cells. Re-expression of BCL6B activated p53 signaling and sensitized HCC cells to 5-fluorouracil. BCL6B is frequently methylated in human HCC and the expression of BCL6B is regulated by promoter region hypermethylation. BCL6B activates p53 signaling by increasing EGR1 expression in HCC.
    Oncotarget 03/2015; · 6.63 Impact Factor
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    ABSTRACT: DNA methylation occurs commonly in non-small cell lung cancer (NSCLC). We sought to determine the frequency and relationship of methylation of key genes involved in the pathways of mitotic checkpoint control, DNA damage repair, apoptosis, and growth factor signaling in these patients. We analyzed the DNA methylation status of eight genes (CHFR, FANCF, MGMT, p16, DAPK, ASC or TMS-1, RAR-B, and CRBP1) using nested methylation-specific PCR (MSP) on over 314 paraffin-embedded, human non-small cell lung cancer samples. We determined the methylation frequency of each gene in addition to the association of the methylation of each gene with other members of the panel. Methylation was a common event in these samples. Our methylation analysis showed frequencies of methylation of 10% for CHFR, 14% for FANCF, 30% for MGMT, 29% for p16, 17% for DAPK, 33% for ASC, 38% for RAR-B, and 7% for CRBP1. There was a strong correlation between methylation of the mitotic G2-M checkpoint gene, CHFR, and methylation of other genes in our panel involved in DNA damage repair (FANCF and MGMT) and apoptosis (DAPK and ASC) but not with other genes in our panel, including p16 (the G1-S checkpoint gene), CRBP1, or RAR-B. In addition, MGMT methylation strongly correlated with the pro-apoptotic gene, ASC. There are distinct associations of methylated genes in non-small cell lung cancer involving DNA damage repair, apoptosis, and the G2-M mitotic checkpoint control. Further studies are warranted to determine whether these methylation patterns have implications for prognosis in addition to prediction of response to chemotherapeutic agents commonly used in the treatment of non-small cell lung cancer, such as radiotherapy and platinum- or taxane-based chemotherapy.
    Discovery medicine 03/2015; 19(104):151-8. · 3.50 Impact Factor
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    ABSTRACT: Aim: To examine epigenetic changes and the function of HOXA11 in human gastric cancer (GC). Materials & methods: Seven GC cell lines, five cases of normal gastric mucosa and 112 cases primary GC samples were used in this study. Results: Expression of HOXA11 and lack of promoter region methylation were found in NCI-N87, MKN45, BGC823 and HGC27 cells. Loss of expression and complete methylation were found in AGS gastric cancer cells. Reduced expression and partial methylation were found in MGC803 and SGC7901 cells. Restoration of HOXA11 expression was induced by 5-aza-2'-deoxycytidine. HOXA11 was methylated in 81.25% (91/112) of primary GCs. The presence of methylation was associated with male gender, tumor size, tumor differentiation and lymph node metastasis (all p < 0.05). Restoration of HOXA11 expression reduced cell proliferation, invasion, migration and induced apoptosis and G2/M phase arrest. HOXA11 was found to inhibit Wnt signaling by upregulating NKD1 expression. Conclusion: Epigenetic silencing of HOXA11 promotes GC proliferation, migration and invasion through activation of Wnt signaling.
    Epigenomics 01/2015; 7(2):1-13. DOI:10.2217/epi.14.92 · 5.22 Impact Factor
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    ABSTRACT: Esophageal squamous cell carcinoma (ESCC) is one of the most common malignancies worldwide. Both genetic and epigenetic changes are involved in esophageal carcinogenesis. CHFR methylation has been found frequently in different cancers and is regarded as a marker of taxane sensitivity. CHFR methylation was found in 0% (0/16) of normal mucosa, 2.9% (1/34) of grade I dysplasia, 0% (0/8) of grade II dysplasia, 12.5% (1/8) of grade III dysplasia and 45% (49/109) of invasive cancer. When treated with docetaxel or paclitaxel, cell viability was lower in CHFR methylated esophageal cancer cells than in unmethylated cells (p<0.05). No difference was found with either cisplatin or VP16 treatment in either group (p>0.05). In CHFR methylated cells, treatment with docetaxel or paclitaxel resulted in almost all cells being suspended in G0/G1 phase of the cell cycle. After 5-AZ treatment, there was an increased fraction of CHFR-methylated cells in S and G2/M phases (p<0.05). In conclusion, CHFR is frequently methylated in ESCC and the expression of CHFR is regulated by promoter region methylation. CHFR methylation is a late stage event in ESCC. Methylation of CHFR sensitized ESCC cells to taxanes. 5-AZ may re-sensitize chemotherapy resistant in refractory tumors by inducing cell cycle phase re-distribution.
    Genes & cancer 01/2015; 6(1-2):38-48.
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    ABSTRACT: BCL6B, a homologue of BCL6, has been reported to be frequently methylated in human gastric cancer. The epigenetic change and the function of BCL6B remains to be elucidated in colorectal cancer. 7 colorectal cancer cell lines (RKO, HT-29, DLD1, LOVO, HCT116, SW480, SW620) and 102 cases of primary colorectal cancer samples were used in this study. Semi-quantitative RT-PCR, methylation specific PCR (MSP), Flow cytometry and western blot were employed. Loss of BCL6B expression was found in HT29, RKO LOVO, SW480, SW620 and DLD1 cells, and reduced expression was found in HCT116 cell line. Complete methylation was found in HT29, RKO, LOVO, SW480, SW620 and DLD1 cells, partial methylation was detected in HCT116 cells. Restoration of BCL6B expression was induced by 5-Aza treatment in these colorectal cancer cells. BCL6B was methylated in 79.4% (81/102) of primary human colorectal cancer and reduced expression was associated with promoter region hypermethylation (p < 0.05). Methylation of BCL6B is associated with late stage (p < 0.05) and lymph node metastasis (p < 0.05). Re-expression of BCL6B inhibited cell proliferation, invasion and migration in RKO and HT29 cells. BCL6B activated P53 signaling and induced apoptosis, Re-expression of BCL6B sensitized RKO and HT29 cells to 5-fluorouracil. In conclusion, BCL6B was frequently methylated in human colorectal cancer and its expression was regulated by promoter region methylation. Methylation of BCL6B is a prognostic and chemo-sensitive marker in colorectal cancer. BCL6B suppresses colorectal cancer growth by activating P53 signaling.
    American Journal of Cancer Research 01/2015; 5(2):651-62. · 3.97 Impact Factor
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    ABSTRACT: RASSF10 has previously been reported to be frequently methylated in a number of malignancies. To understand the importance of RASSF10 inactivation in colorectal carcinogenesis, eight colorectal cancer cell lines, 89 cases of primary colorectal cancer and 5 cases of normal colorectal mucosa were examined. Methylation specific PCR, western blot, siRNA, gene expression array and xenograft mice were employed. The expression of RASSF10 was regulated by promoter regional methylation in colorectal cancer cells. RASSF10 was methylated in 60.7% (54/89) of primary colorectal cancers and was positively associated with tumor stage (p < 0.05) and metastasis (p < 0.05). Restoration of RASSF10 led to inhibition of colorectal cancer cell proliferation in vitro and in vivo and increased apoptosis. Gene expression arrays discovered RASSF10 inhibition of MDM2 expression as a mediator of these effects, which was confirmed with RT- PCR and western blot. RASSF10 was shown to activate P53 signaling in RKO and HCT116 cells after UV exposure, and sensitized these cells to docetaxel. In conclusion, our study demonstrates RASSF10 is frequently methylated in human colorectal cancer leading to loss of expression. RASSF10 normally suppresses human colorectal cancer growth by activating P53 signaling in colorectal cancer, and restored expression sensitizes colorectal cancer to docetaxel.
    Oncotarget 12/2014; · 6.63 Impact Factor
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    ABSTRACT: Identifying biomarkers in body fluids may improve the non-invasive detection of colorectal cancer (CRC). Previously we identified N-Myc downstream-regulated gene 4 (NDRG4) and GATA binding protein 5 (GATA5) methylation as promising biomarkers for CRC in stool DNA. Here, we examined the utility of NDRG4, GATA5, and two additional markers (Forkhead box protein E1 (FOXE1) and spectrin repeat containing nuclear envelope 1 (SYNE1)) promoter methylation as biomarkers in plasma DNA. Quantitative methylation-specific PCR was performed on plasma DNA from 220 CRC patients and 684 non-cancer controls, divided in a training and test set. Receiver operating characteristic analysis was performed to measure the area under the curve of GATA5, NDRG4, SYNE1 and FOXE1 methylation. Functional assays were performed in SYNE1 and FOXE1 stably transfected cell lines. The sensitivity of NDRG4, GATA5, FOXE1 and SYNE1 methylation in all stages of CRC (154 cases, 444 controls) was 27% (95%CI=20%-34%), 18% (95%CI=12%-24%), 46% (95%CI=38%-54%) and 47% (95%CI=39%-55%), with a specificity of 95% (95%CI=93%-97%), 99% (95%CI=98%-100%), 93% (95%CI=91%-95%) and 96% (95%CI=94%-98%) respectively. Combining SYNE1 and FOXE1, increased the sensitivity to 56% (95%CI=48%-64%), while the specificity decreased to 90% (95%CI=87%-93%) in the training set and to 58% sensitivity (95%CI=46%-70%) and 91% specificity (95%CI=80%-100%) in a test set (66 cases, 240 controls). SYNE1 overexpression showed no major differences in cell proliferation, migration and invasion compared to controls. Overexpression of FOXE1 significantly decreased the number of colonies in SW480 and HCT116 cell lines. Overall our data suggests that SYNE1 and FOXE1 are promising markers for CRC detection. Copyright © 2014, American Association for Cancer Research.
    Cancer Prevention Research 12/2014; 8(2). DOI:10.1158/1940-6207.CAPR-14-0198 · 5.27 Impact Factor
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    ABSTRACT: Thyroid cancer is the most common endocrine malignant disease and the incidence is increasing. DACT2 was found frequently methylated in human lung cancer and hepatocellular carcinoma. To explore the epigenetic change and the role of DACT2 in thyroid cancer, 7 thyroid cancer cell lines, 10 cases of non-cancerous thyroid tissue samples and 99 cases of primary thyroid cancer samples were involved in this study. DACT2 was expressed and unmethylated in K1, SW579, FTC-133, TT, W3 and 8505C cell lines. Loss of expression and complete methylation was found in TPC-1 cells. Restoration of DACT2 expression was induced by 5-aza-2'deoxycytidine treatment. It demonstrates that the expression of DACT2 was regulated by promoter region methylation. In human primary papillary thyroid cancer, 64.6% (64/99) was methylated and methylation of DACT2 was related to lymph node metastasis (p<0.01). Re-expression of DACT2 suppresses cell proliferation, invasion and migration in TPC-1 cells. The activity of TCF/LEF was inhibited by DACT2 in wild-type or mutant β-catenin cells. The activity of TCF/LEF was increased by co-transfecting DACT2 and Dvl2 in wild-type or mutant β-catenin cells. Overexpression of wild-type β-catenin promotes cell migration and invasion in DACT2 stably expressed cells. The expression of β-catenin, c-myc, cyclinD1 and MMP-9 were decreased and the level of phosphorylated β-catenin (p-β-catenin) was increased after restoration of DACT2 expression in TPC-1 cells. The expression of β-catenin, c-myc, cyclinD1 and MMP-9 were increased and the level of p-β-catenin was reduced after knockdown of DACT2 in W3 and SW579 cells. These results suggest that DACT2 suppresses human papillary thyroid cancer growth and metastasis by inhibiting Wnt signaling. In conclusion, DACT2 is frequently methylated in papillary thyroid cancer. DACT2 expression was regulated by promoter region methylation. DACT2 suppresses papillary thyroid cancer proliferation and metastasis by inhibiting Wnt signaling.
    PLoS ONE 11/2014; 9(11):e112336. DOI:10.1371/journal.pone.0112336 · 3.53 Impact Factor
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    ABSTRACT: Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer. Here, we describe the genomic landscape of 496 PTCs. We observed a low frequency of somatic alterations (relative to other carcinomas) and extended the set of known PTC driver alterations to include EIF1AX, PPM1D, and CHEK2 and diverse gene fusions. These discoveries reduced the fraction of PTC cases with unknown oncogenic driver from 25% to 3.5%. Combined analyses of genomic variants, gene expression, and methylation demonstrated that different driver groups lead to different pathologies with distinct signaling and differentiation characteristics. Similarly, we identified distinct molecular subgroups of BRAF-mutant tumors, and multidimensional analyses highlighted a potential involvement of oncomiRs in less-differentiated subgroups. Our results propose a reclassification of thyroid cancers into molecular subtypes that better reflect their underlying signaling and differentiation properties, which has the potential to improve their pathological classification and better inform the management of the disease.
    Cell 10/2014; 159(3):676-90. DOI:10.1016/j.cell.2014.09.050. · 33.12 Impact Factor
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    ABSTRACT: Recent genomic analyses of pathologically defined tumor types identify ''within-a-tissue'' disease sub-types. However, the extent to which genomic sig-natures are shared across tissues is still unclear. We performed an integrative analysis using five genome-wide platforms and one proteomic platform on 3,527 specimens from 12 cancer types, revealing a unified classification into 11 major subtypes. Five subtypes were nearly identical to their tissue-of-origin counterparts, but several distinct cancer types were found to converge into common subtypes. Lung squamous, head and neck, and a subset of bladder cancers coalesced into one subtype typified by TP53 alterations, TP63 amplifications, and high expression of immune and proliferation pathway genes. Of note, bladder cancers split into three pan-cancer subtypes. The multiplatform classification, while correlated with tissue-of-origin, provides inde-pendent information for predicting clinical outcomes. All data sets are available for data-mining from a uni-fied resource to support further biological discov-eries and insights into novel therapeutic strategies. INTRODUCTION
    Cell 08/2014; DOI:10.1016/j.cell.2014.06.049 · 33.12 Impact Factor
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    ABSTRACT: Adenocarcinoma of the lung is the leading cause of cancer death worldwide. Here we report molecular profiling of 230 resected lung adenocarcinomas using messenger RNA, microRNA and DNA sequencing integrated with copy number, methylation and proteomic analyses. High rates of somatic mutation were seen (mean 8.9 mutations per megabase). Eighteen genes were statistically significantly mutated, including RIT1 activating mutations and newly described loss-of-function MGA mutations which are mutually exclusive with focal MYC amplification. EGFR mutations were more frequent in female patients, whereas mutations in RBM10 were more common in males. Aberrations in NF1, MET, ERBB2 and RIT1 occurred in 13% of cases and were enriched in samples otherwise lacking an activated oncogene, suggesting a driver role for these events in certain tumours. DNA and mRNA sequence from the same tumour highlighted splicing alterations driven by somatic genomic changes, including exon 14 skipping in MET mRNA in 4% of cases. MAPK a
    Nature 07/2014; 511(7517-7511):543-550. DOI:10.1038/nature13385 · 42.35 Impact Factor
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    ABSTRACT: Head and neck cancers (HNCs) represent a significant and ever-growing burden to the modern society, mainly due to the lack of early diagnostic methods. A significant number of HNCs is often associated with drinking, smoking, chewing beetle nut, and human papilloma virus (HPV) infections. We have analyzed DNA methylation patterns in tumor and normal tissue samples collected from head and neck squamous cell carcinoma (HNSCC) patients who were smokers. We have identified novel methylation sites in the promoter of the mediator complex subunit 15 (MED15/PCQAP) gene (encoing a co-factor important for regulation of transcription initiation for promoters of many genes), hypermethylated specifically in tumor cells. Two clusters of CpG dinucleotides methylated in tumors, but not in normal tissue from the same patients, were identified. These CpG methylation events in saliva samples were further validated in a separate cohort of HNSCC patients (who developed cancer due to smoking or HPV infections) and healthy controls using methylation-specific PCR (MSP). We used saliva as a biological medium because of its non-invasive nature, close proximity to the tumors, easiness and it is an economically viable option for large-scale screening studies. The methylation levels for the two identified CpG clusters were significantly different between the saliva samples collected from healthy controls and HNSCC individuals (Welch's t-test returning P < 0.05 and Mann-Whitney test P < 0.01 for both). The developed MSP assays also provided a good discriminative ability with AUC values of 0.70 (P < 0.01) and 0.63 (P < 0.05). The identified novel CpG methylation sites may serve as potential non-invasive biomarkers for detecting HNSCC.
    Biomarker insights 07/2014; 9:53-60. DOI:10.4137/BMI.S16199
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    ABSTRACT: Purpose: Data on the prognostic significance of promoter CpG island methylation in colorectal cancer (CRC) are conflicting, possibly due to associations between methylation and other factors affecting survival such as genetic alterations and use of adjuvant therapy. Here, we examine the prognostic impact of promoter methylation in patients with CRC treated with surgery alone in the context of microsatellite instability (MSI), BRAF and KRAS mutations. Experimental Methods: One hundred and seventy-three CRCs were analyzed for promoter methylation of 19 tumor suppressor and DNA repair genes, the CpG island methylator phenotype (CIMP), MSI, the exon 15 V600E BRAF mutation and KRAS codon 12 and 13 mutations. Results: Unsupervised hierarchical clustering based on methylation status of 19 genes revealed three subgroups: cluster 1 [CL1, 57% (98/173) of CRCs], cluster 2 [CL2, 25% (43/173) of CRCs], and cluster 3 [CL3, 18% (32/173) of CRCs]. CL3 had the highest methylation index (0.25, 0.49, and 0.69, respectively, P =< 0.01) and was strongly associated with CIMP (P < 0.01). Subgroup analysis for tumor stage, MSI, and BRAF status showed no statistically significant differences in survival between CL1, CL2, and CL3 nor between CIMP and non-CIMP CRCs. Analyzing genes separately revealed that CHFR promoter methylation was associated with a poor prognosis in stage II, microsatellite stability (MSS), BRAF wild-type (WT) CRCs: multivariate Cox proportional HR = 3.89 [95% confidence interval (CI), 1.58-9.60, P < 0.01; n = 66] and HR = 2.11 (95% CI, 0.95-4.69, P = 0.068, n = 136) in a second independent population-based study. Conclusions: CHFR promoter CpG island methylation, which is associated with MSI, also occurs frequently in MSS CRCs and is a promising prognostic marker in stage II, MSS, BRAF WT CRCs. (C) 2014 AACR.
    Clinical Cancer Research 06/2014; 20(12):3261-71. DOI:10.1158/1078-0432.CCR-12-3734 · 8.19 Impact Factor
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    ABSTRACT: Gastric cancer (GC) is the fourth most common malignancy in males and the fifth most common malignancy in females worldwide. DACH1 is frequently methylated in hepatic and colorectal cancer. To further understand the regulation and mechanism of DACH1 in GC, eight GC cell lines, eight cases of normal gastric mucosa, 98 cases of primary GC and 50 cases of adjacent non-tumour tissues were examined. Methylation-specific PCR, western blot, transwell assay and xenograft mice were used in this study. Loss of DACH1 expression correlated with promoter region methylation in GC cells, and re-expression was induced by 5-Aza-2'-deoxyazacytidine. DACH1 is methylated in 63.3% (62/98) of primary GC and 38% (19/50) of adjacent non-tumour tissues, while no methylation was found in normal gastric mucosa. Methylation of DACH1 correlated with reduced expression of DACH1 (P < 0.01), late tumour stage (stage III/IV) (P < 0.01) and lymph node metastasis (P < 0.05). DACH1 expression inhibited epithelial-mesenchymal transition and metastasis by inhibiting transforming growth factor (TGF)-β signalling and suppressed GC cell proliferation through inducing G2/M phase arrest. The tumour size is smaller in DACH1-expressed BGC823 cell xenograft mice than in unexpressed group (P < 0.01). Restoration of DACH1 expression also sensitized GC cells to docetaxel. These studies suggest that DACH1 is frequently methylated in human GC and expression of DACH1 was controlled by promoter region methylation. DACH1 suppresses GC proliferation, invasion and metastasis by inhibiting TGF-β signalling pathways both in vitro and in vivo. Epigenetic silencing DACH1 may induce GC cells' resistance to docetaxel.
    Journal of Cellular and Molecular Medicine 06/2014; 18(12). DOI:10.1111/jcmm.12325 · 3.70 Impact Factor
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    ABSTRACT: Epidemiological evidence suggests that HIV-infected individuals are at increased risk of lung cancer, but no data exist because large computed tomography (CT) screening trials routinely exclude HIV-infected participants. From 2006 to 2013, we conducted the world's first lung cancer screening trial of 224 HIV-infected current/former smokers to assess the CT detection rates of lung cancer. We also used 130 HIV-infected patients with known lung cancer to determine radiographic markers of lung cancer risk using multivariate analysis. Median age was 48 years with 34 pack-years smoked. During 678 person-years, one lung cancer was found on incident screening. Besides this lung cancer case, 18 deaths (8%) occurred, but none were cancer related. There were no interim diagnoses of lung or extrapulmonary cancers. None of the pulmonary nodules detected in 48 participants at baseline were diagnosed as cancer by study end. The heterogeneity of emphysema across the entire lung as measured by CT densitometry was significantly higher in HIV-infected subjects with lung cancer compared with the heterogeneity of emphysema in those without HIV (p ≤ 0.01). On multivariate regression analysis, increased age, higher smoking pack-years, low CD4 nadir, and increased heterogeneity of emphysema on quantitative CT imaging were all significantly associated with lung cancer. Despite a high rate of active smoking among HIV-infected participants, only one lung cancer was detected in 678 patient-years. This was probably because of the young age of participants suggesting that CT screening of high-risk populations should strongly consider advanced age as a critical inclusion criterion. Future screening trials in urban American must also incorporate robust measures to ensure HIV patient compliance, adherence, and smoking cessation.
    Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 06/2014; 9(6):752-9. DOI:10.1097/JTO.0000000000000161 · 5.80 Impact Factor
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    ABSTRACT: Improved prognostic stratification of patients with TNM stage II colorectal cancer is desired, since 20-30% of high-risk stage II patients may die within five years of diagnosis. This study was conducted to investigate REarranged during Transfection (RET) gene promoter CpG island methylation as a possible prognostic marker for TNM stage II colorectal cancer patients (CRC) patients. The utility of RET promoter CpG island methylation in tumors of stage II CRC patients as a prognostic biomarker for CRC related death was studied in three independent series (including 233, 231, and 294 TNM stage II patients, respectively) by using MSP and pyrosequencing. The prognostic value of RET promoter CpG island methylation was analyzed by using Cox regression analysis. In the first series, analyzed by MSP, CRC stage II patients (n=233) with RET methylated tumors, had a significantly worse overall survival as compared to those with unmethylated tumors (HRmultivariable = 2.51, 95%-CI: 1.42-4.43). Despite a significant prognostic effect of RET methylation in stage III patients of a second series, analyzed by MSP, the prognostic effect in stage II patients (n=231) was not statistically significant (HRmultivariable = 1.16, 95%-CI 0.71-1.92). The third series (n=294), analyzed by pyrosequencing, confirmed a statistically significant association between RET methylation and poor overall survival in stage II patients (HRmultivariable = 1.91, 95%-CI: 1.03-3.52). Our results show that RET promoter CpG island methylation, analyzed by two different techniques, is associated with a poor prognosis in stage II CRC in two independent series and a poor prognosis in stage III CRC in one series. RET methylation may serve as a useful and robust tool for clinical practice to identify high-risk stage II CRC patients with a poor prognosis. This merits further investigation.
    Molecular oncology 05/2014; DOI:10.1016/j.molonc.2014.01.011 · 5.94 Impact Factor

Publication Stats

52k Citations
3,273.25 Total Impact Points


  • 2015
    • University of Pittsburgh
      • Hillman Cancer Center
      Pittsburgh, Pennsylvania, United States
  • 2012–2015
    • Chinese PLA General Hospital (301 Hospital)
      Peping, Beijing, China
    • 307 Hospital of the Chinese People's Liberation Army
      Peping, Beijing, China
  • 1993–2015
    • Johns Hopkins University
      • • Department of Pathology
      • • Department of Surgery
      • • Institute of the History of Medicine
      • • Department of Otolaryngology - Head and Neck Surgery
      Baltimore, Maryland, United States
  • 1995–2014
    • Johns Hopkins Medicine
      • • Department of Medical Oncology
      • • Sidney Kimmel Comprehensive Cancer Center
      • • Department of Otolaryngology - Head and Neck Surgery
      Baltimore, Maryland, United States
    • University of Maryland, Baltimore
      Baltimore, Maryland, United States
  • 2013
    • Emory University
      Atlanta, Georgia, United States
    • Nankai University
      T’ien-ching-shih, Tianjin Shi, China
  • 2002–2013
    • Maastricht University
      • • Department of Epidemiology
      • • Pathologie
      Maestricht, Limburg, Netherlands
    • Universidad de Navarra
      Iruña, Navarre, Spain
    • Centro Nacional de Investigaciones Oncológicas
      • Molecular Pathology Programme
      Madrid, Madrid, Spain
  • 2011
    • RWTH Aachen University
      Aachen, North Rhine-Westphalia, Germany
  • 2009–2011
    • Maastricht Universitair Medisch Centrum
      • Central Diagnostic Laboratory
      Maestricht, Limburg, Netherlands
  • 2008
    • Mercy Medical Center
      Baltimore, Maryland, United States
    • Case Western Reserve University
      Cleveland, Ohio, United States
  • 2006
    • Johns Hopkins Bloomberg School of Public Health
      • Department of Epidemiology
      Baltimore, Maryland, United States
  • 2005
    • National Cancer Institute (USA)
      베서스다, Maryland, United States
  • 2004
    • Louisiana State University Health Sciences Center New Orleans
      New Orleans, Louisiana, United States
    • Tokyo Medical and Dental University
      • Department of Molecular Oncology
      Edo, Tōkyō, Japan
  • 2003
    • Howard Hughes Medical Institute
      Ashburn, Virginia, United States
    • Instituto de Salud Carlos III
      Madrid, Madrid, Spain
  • 2001
    • Sarcoma Oncology Center
      Santa Monica, California, United States
    • Fox Chase Cancer Center
      Philadelphia, Pennsylvania, United States
  • 2000
    • Minneapolis Veterans Affairs Hospital
      Minneapolis, Minnesota, United States
  • 1999
    • Hospital de la Santa Creu i Sant Pau
      Barcino, Catalonia, Spain
    • Medical College of Wisconsin
      • Department of Surgery
      Milwaukee, WI, United States
  • 1998
    • Lovelace Respiratory Research Institute
      • Respiratory Immunology and Asthma Program
      Albuquerque, New Mexico, United States