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ABSTRACT: Chemically-induced urinary bladder cancer in rodents has long been used as a reliable model to study the biopathology of urinary bladder neoplasia and to develop therapeutic strategies against human tumors. Knowledge of the genetic basis underlying carcinogenesis would greatly enhance usability and usefulness of this model for the purposes of comparative pathology. However, little is known about the cytogenetic characteristics of rodent urinary bladder tumors. Accordingly, pathological and negative control specimens were collected for cytogenetic evaluation, from an ongoing mouse urinary bladder N-butyl-N-(4-hydroxybutyl) nitrosamine-induced carcinogenesis study. Histopathological analysis characterized the pathological sample as a papillary urothelial carcinoma. Conventional cytogenetic analysis revealed the presence of 66.3 % tetraploid cells. Fluorescent in situ hybridization using chromosome paint probes allowed the detection of a reciprocal translocation involving chromosomes 4 and 14 (containing the murine homologues to human p16 and retinoblastoma tumor-suppressor genes) in 42 % of tetraploid cells. The control sample showed no histological or cytogenetic changes. CDKN2A and RB1 loss of heterozygosity is associated with human early and advanced urinary bladder cancer, respectively. Thus, the present data paves the way for further studies concerning the molecular mechanisms of urinary bladder carcinogenesis.
Tumor Biology 05/2013; · 1.94 Impact Factor
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ABSTRACT: Background/Aim: Canine cutaneous histiocytoma (CCH) is a tumour that undergoes spontaneous regression. The aim of this study was to establish a possible relationship between regression of CCH and tumoural cell proliferation and apoptosis.
Immunostaining with Ki-67 antigen and the terminal deoxytransferase (TdT) deoxyuridine-5'-triphosphated (dUTP) nick-end labelling (TUNEL) method were performed on 93 specimens of CCH, grouped into four histological groups.
The proliferative index evaluated with Ki-67 antigen expression was on average 23.56±7.91%. The apoptotic index determined by the TUNEL method was on average 39.37±5.87%. Neither the proliferative nor apoptotic index differed between histological groups. Moreover, the proliferative and apoptotic indices did not correlate significantly. However, apoptotic activity was higher than proliferative activity in almost all tumours.
A reduction of proliferation or an increase of apoptosis does not appear to justify regression of CCH. However, our results suggest that an imbalance between cell proliferation and apoptotic cell death plays a significant role in spontaneous regression of CCH.
Anticancer research 04/2013; 33(4):1397-400. · 1.73 Impact Factor
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ABSTRACT: In order to investigate the immune mechanisms involved in regression of canine cutaneous histicytoma (CCH), major histocompatibility complex (MHC) class-II immuno-expression and the number of T- and B-lymphocytes and macrophages were analyzed in 93 cases of CCH. MHC class-II was also studied in 16 cases of CCH by immunoelectron microscopy. All tumors expressed MHC class-II, and two major staining patterns were identified: focal juxtanuclear cytoplasmic staining and rim-like staining along the cell periphery. The MHC class-II labelling pattern and T- and B-lymphocyte infiltrates were associated with tumor regression. In regressing lesions, MHC class-II molecules shift to the cell surface and an increase of both T- and B-lymphocytes were noted. The increasing expression of MHC class-II molecules on the cell surface could be a significant factor for the onset and progression of tumour regression.
In vivo (Athens, Greece) 03/2013; 27(2):257-62. · 1.17 Impact Factor
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ABSTRACT: Cisplatin (CDDP)-based chemotherapy is a commonly treatment for advanced urothelial carcinoma. However, episodes of cisplatin resistance have been referenced. Recently it has been reported that everolimus (RAD001) could have an important role to play in bladder-cancer treatment and that mTOR inhibitors may restore chemosensitivity in resistant tumours. The aim of this study was to assess RAD001 in vitro ability to enhance CDDP cytotoxicity in three human bladder-cancer cell lines. Over the course of 72h, the cells were exposed to different concentrations of CDDP and RAD001, isolated or combined. Treatment with CDDP statistically (P<0.05) decreased cell proliferation in cell lines in a dose-dependent manner. The anti-proliferative activity of CDDP used in combination with RAD001 was statistically significant (P<0.05) in the cell lines at all concentrations tested. RAD001 had a therapeutic effect when used in combination with CDDP and could therefore be a useful anti-cancer drug combination for patients with bladder cancer.
Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie 03/2013; 67(2):116-21. · 2.24 Impact Factor
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Rui Medeiros,
Deolinda Pereira,
Noémia Afonso,
Carlos Palmeira,
Cristina Faleiro,
Carlos Afonso-Lopes,
Margarida Freitas-Silva,
André Vasconcelos,
Sandra Costa,
Teresa Osório, Carlos Lopes
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Ricardo Ribeiro,
Cátia Monteiro,
Ricardo Silvestre,
Angela Castela,
Helena Coutinho,
Avelino Fraga,
Paulo Príncipe,
Carlos Lobato,
Carla Costa,
Anabela Cordeiro-da-Silva,
José Manuel Lopes, Carlos Lopes,
Rui Medeiros
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ABSTRACT: A body of growing evidence now implicates white adipose tissue as a relevant source of stromal progenitor cells recruited to the tumor microenvironment to form supportive tumor stroma. While the role of periprostatic (PP) adipose tissue in prostate cancer progression has been barely appreciated, we sought to determine the progenitor cell population in PP adipose tissue and the association with prostate cancer. We isolated and characterized CD31(-)CD34(+)CD45(-)CD146(-) progenitor cells (adipose-derived stem cells [ASC]) in paired samples of PP and preperitoneal visceral adipose tissue from prostate tissue and peripheral blood mononuclear cells of prostate cancer and nodular prostatic hyperplasia patients. ASC were quantified by flow cytometry and confirmed through target gene expression. Here we show a significantly higher amount of ASC in PP than in visceral adipose tissue, independent of body mass index and prostatic disease. In the prostate, ASC are increased in cancer compared with prostatic nodular hyperplasia patients. Concordantly, adipsin gene (CFD) expression, which is known to be up-regulated in adipose stem cells, was overexpressed in PP adipose tissue, in the prostate of cancer patients and in prostate CD31(-)CD34(+)CD45(-)CD146(-) sorted cells. ASC were found at higher levels in the blood of prostate cancer patients simultaneously overweight/obese. Present findings indicate that PP adipose tissue is a reservoir of progenitor cells with the potential to migrate towards prostate tumors, although its clinical significance merits further evaluation.
Experimental Biology and Medicine 10/2012; · 2.64 Impact Factor
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Ricardo Ribeiro,
Catia Monteiro,
Victoria Catalan,
Pingzhao Hu,
Virginia Cunha,
Amaia Rodriguez,
Javier Gomez-Ambrosi,
Avelino Fraga,
Paulo Principe,
Carlos Lobato,
Francisco Lobo,
Antonio Morais,
Vitor Silva,
Jose Sanches-Magalhaes,
Jorge Oliveira,
Francisco Pina, Carlos Lopes,
Rui Medeiros,
Gema Fruhbeck
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ABSTRACT: BACKGROUND: Periprostatic (PP) adipose tissue surrounds the prostate, an organ with high predisposition to become malignant. Frequently growing prostatic tumor cells extend beyond the prostatic organ towards this fat depot. This study aimed to determine the genome-wide expression of genes in PP adipose tissue in obesity/overweight (OB/OW) and prostate cancer. METHODS: Differentially expressed genes in human PP adipose tissue were identified using microarrays. Analyses were conducted according to donors' body mass index characteristics (OB/OW vs. lean) and prostate disease (extra prostatic cancer vs. organ confined prostate cancer vs. benign prostatic hyperplasia). Selected genes with altered expression were validated by real-time PCR. Ingenuity Pathway Analysis (IPA) was used to investigate gene ontology, canonical pathways and functional networks. RESULTS: In the PP adipose tissue of OB/OW subjects, we found altered expression of genes encoding molecules involved in adipogenic/anti-lipolytic, proliferative/anti-apoptotic, and mild immunoinflammatory processes (e.g. FADS1, down-regulated, and LEP and ANGPT1, both up-regulated). Conversely, in the PP adipose tissue of subjects with prostate cancer, altered genes were related to adipose tissue cellular activity (increased cell proliferation/differentiation, cell cycle activation and anti-apoptosis), whereas a downward impact on immunity and inflammation was also observed, mostly related with the complement (down-regulation of CFH). Interestingly, we found that the microRNA MIRLET7A2 was overexpressed in the PP adipose tissue of prostate cancer patients. CONCLUSIONS: Obesity and excess adiposity modified the expression of PP adipose tissue genes to ultimately foster fat mass growth. In patients with prostate cancer the expression profile of PP adipose tissue accounted for hypercellularity and reduced immunosurveillance. Both findings may be liable to promote a favorable environment for prostate cancer progression. Please see related article: http://www.biomedcentral.com/1741-7015/10/109.
BMC Medicine 09/2012; 10(1):108. · 6.03 Impact Factor
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ABSTRACT: Bracken (Pteridium aquilinum) is a carcinogenic plant whose main toxin, ptaquiloside, causes cancer in farm and laboratory animals. Ptaquiloside contaminates underground waters as well as meat and milk from bracken-grazing animals and is a suspected human carcinogen. A better understanding of the underlying mechanisms of carcinogenesis can be achieved by studying the early stages of this process. Unfortunately, most research on ptaquiloside has focused on the late, malignant, lesions, so the early changes of ptaquiloside-induced carcinogenesis remain largely unknown. This study aims to characterize early-stage ptaquiloside-induced urinary bladder lesions both morphologically and immunohistochemically. 12 male CD-1 mice were administered 0.5 mg ptaquiloside intraperitoneally, weekly, for 15 weeks, followed by 15 weeks without treatment. 12 control animals were administered saline. Bladders were tested immunohistochemically for antibodies against a cell proliferation marker (Ki-67), and two cell adhesion markers (E-cadherin and β-catenin). Two exposed animals died during the work. Six ptaquiloside-exposed mice developed low-grade and two developed high grade urothelial dysplasia. No lesions were detected on control animals. Significantly, increased (p < 0.05) Ki-67 labeling indices were found on dysplastic urothelium from ptaquiloside-exposed mice, compared with controls. No differences were found concerning E-cadherin and β-catenin expression. Early-stage ptaquiloside-induced urothelial lesions show increased cell proliferation but there is no evidence for reduced intercellular adhesiveness, though this may be a later event in tumor progression. © 2012 Wiley Periodicals, Inc. Environ Toxicol, 2012.
Environmental Toxicology 08/2012; · 2.41 Impact Factor
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ABSTRACT: Ptaquiloside, a norsesquiterpene glycoside from bracken (Pteridium aquilinum), is a known carcinogen towards animals. Its genotoxicity is mainly attributed to its DNA-alkylating and clastogenic properties. This study analyses various modes of genotoxic action of ptaquiloside in human mononuclear blood cells. The alkaline comet assay was performed on cells exposed to 5μg/ml ptaquiloside for 5, 10, 20, 30, 40 or 50min. Tail length was used as a DNA-damage parameter. Assays to determine structural and numerical chromosomal aberrations and sister-chromatid exchange were conducted on cells exposed to 5, 10 or 20μg/ml ptaquiloside for 48h. The tail length showed maximum DNA damage at 20-30min, diminishing onwards. Highly significant (p<0.001) dose-dependent increases in structural and numerical chromosomal aberrations and SCE were observed in response to ptaquiloside. These results indicate that ptaquiloside is not only a DNA-alkylating agent, but expresses its genotoxicity through multiple mechanisms including clastogenesis, aneugenesis and the mechanism underlying SCE induction, which is not entirely understood. Recent studies support the role played by aneuploidy in oncogenesis, highlighting the importance of this endpoint for mutagenicity screening. SCE are thought to represent the long-term effects of mutagens and are an important genotoxicity biomarker. The present results also agree with data from epidemiological studies and from animal in vivo studies, further supporting the hypothesis that ptaquiloside may represent a significant threat to human health.
Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis 04/2012; 747(1):77-81. · 2.85 Impact Factor
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Ricardo Ribeiro,
Cátia Monteiro,
Virgínia Cunha,
Maria José Oliveira,
Mariana Freitas,
Avelino Fraga,
Paulo Príncipe,
Carlos Lobato,
Francisco Lobo,
António Morais,
Vítor Silva,
José Sanches-Magalhães,
Jorge Oliveira,
Francisco Pina,
Anabela Mota-Pinto, Carlos Lopes,
Rui Medeiros
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ABSTRACT: Obesity is associated with prostate cancer aggressiveness and mortality. The contribution of periprostatic adipose tissue, which is often infiltrated by malignant cells, to cancer progression is largely unknown. Thus, this study aimed to determine if periprostatic adipose tissue is linked with aggressive tumor biology in prostate cancer.
Supernatants of whole adipose tissue (explants) or stromal vascular fraction (SVF) from paired fat samples of periprostatic (PP) and pre-peritoneal visceral (VIS) anatomic origin from different donors were prepared and analyzed for matrix metalloproteinases (MMPs) 2 and 9 activity. The effects of those conditioned media (CM) on growth and migration of hormone-refractory (PC-3) and hormone-sensitive (LNCaP) prostate cancer cells were measured.
We show here that PP adipose tissue of overweight men has higher MMP9 activity in comparison with normal subjects. The observed increased activities of both MMP2 and MMP9 in PP whole adipose tissue explants, likely reveal the contribution of adipocytes plus stromal-vascular fraction (SVF) as opposed to SVF alone. MMP2 activity was higher for PP when compared to VIS adipose tissue. When PC-3 cells were stimulated with CM from PP adipose tissue explants, increased proliferative and migratory capacities were observed, but not in the presence of SVF. Conversely, when LNCaP cells were stimulated with PP explants CM, we found enhanced motility despite the inhibition of proliferation, whereas CM derived from SVF increased both cell proliferation and motility. Explants culture and using adipose tissue of PP origin are most effective in promoting proliferation and migration of PC-3 cells, as respectively compared with SVF culture and using adipose tissue of VIS origin. In LNCaP cells, while explants CM cause increased migration compared to SVF, the use of PP adipose tissue to generate CM result in the increase of both cellular proliferation and migration.
Our findings suggest that the PP depot has the potential to modulate extra-prostatic tumor cells' microenvironment through increased MMPs activity and to promote prostate cancer cell survival and migration. Adipocyte-derived factors likely have a relevant proliferative and motile role.
Journal of Experimental & Clinical Cancer Research 04/2012; 31:32. · 2.15 Impact Factor
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ABSTRACT: The importance of oncology diseases as a cause of morbidity and mortality is increasing worldwide, and their social impact is being recognized due to economic and social costs involved in prevention, treatment and rehabilitation. Head and neck cancer is one of the six most prevalent neoplasms worldwide, with an estimated 900,000 new cases diagnosed annually. Regardless of tumor site, deterioration of basic functions affecting head and neck areas are perceived and affect patients' lives. Appropriate cancer registration may provide a better analysis of health-related quality of life outcomes. In this study, 380 head and neck cancer patients were evaluated. The study showed that women have lower overall Quality of Life results. It also emphasizes the importance of early diagnosis, which often relates to stages with better prognosis and better Quality of Life outcomes. The study concluded that tumor location has an impact on Quality of Life self-perception. Values of Health Related Quality of Life should be analyzed along with socio-demographic and clinical variables in order to better understand the epidemiology, pathogenesis, and prevention of Head and Neck Cancer.
Revista Brasileira de Epidemiologia 03/2012; 15(1):38-48.
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ABSTRACT: The purpose of our study was to determine whether the amounts of circulating DNA (cDNA) could discriminate between NSCLC patients and healthy individuals and assess its value as a prognostic marker of this disease.
We conducted a study of 309 individuals and the cDNA levels were assessed through real-time PCR methodology.
We found increased cDNA levels in NSCLC patients compared to control individuals. We also found a decreased overall survival time in patients presenting high cDNA levels, when compared to lower cDNA concentrations.
Quantification of cDNA may be a good tool for NSCLC detection with potential for clinical applicability.
PLoS ONE 01/2012; 7(6):e38559. · 4.09 Impact Factor
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Carmen Vasconcelos-Nóbrega,
Rosario Pinto-Leite,
Regina Arantes-Rodrigues,
Rita Ferreira,
Paulo Brochado,
Maria L Cardoso,
Carlos Palmeira,
Alexandre Salvador,
Catarina I Guedes-Teixeira,
Aura Colaço,
Luis F Palomino, Carlos Lopes,
Lúcio Santos,
Paula A Oliveira
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ABSTRACT: OBJECTIVE: To evaluate the influence of Everolimus (RAD001) on chemically induced urothelial lesions in mice and its influence on in vitro human bladder cancer cell lines. METHODS: ICR male mice were given N-butyl-N-(4-hydroxybutyl) nitrosamine in drinking water for a period of 12 weeks. Subsequently, RAD001 was administered via oral gavage, for 6 weeks. At the end of the experiment, all the animals were sacrificed and tumor development was determined by means of histopathologic evaluation; mammalian target of rapamycin (mTOR) expressivity was evaluated by immunohistochemistry. Three human bladder cancer cell lines (T24, HT1376, and 5637) were treated using a range of RAD001 concentrations. MTT assay, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and flow cytometry were used to assess cell proliferation, apoptosis index, and cell cycle analysis, respectively. Immunoblotting analysis of 3 cell line extracts using mTOR and Akt antibodies was performed in order to study the expression of Akt and mTOR proteins and their phosphorylated forms. RESULTS: The incidence of urothelial lesions in animals treated with RAD001 was similar to those animals not treated. RAD001 did not block T24 and HT1376 cell proliferation or induce apoptosis. A reduction in cell proliferation rate and therefore G(0)/G(1) phase arrest, as well as a statistically significant induction of apoptosis (P = 0.001), was only observed in the 5637 cell line. CONCLUSION: RAD001 seems not to have a significant effect on chemically induced murine bladder tumors. The effect of RAD001 on tumor proliferation and apoptosis was achieved only in superficial derived bladder cancer cell line, no effect was observed in invasive cell lines.
Urologic Oncology 12/2011; · 3.22 Impact Factor
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ABSTRACT: Quality of Life is a distinct and important emerging health focus, guiding practice and research. The routine Quality of Life evaluation in clinical, economic, and epidemiological studies and in medical practice promises a better Quality of Life and improved health resources optimization. The use of information technology and a Knowledge Management System related to Quality of Life assessment is essential to routine clinical evaluation and can define a clinical research methodology that is more efficient and better organized. In this paper, a Validation Model using the Quality of Life informatics platform is presented. Portuguese PC-software using European Organization for Research and Treatment of Cancer questionnaires (EORTC-QLQ C30 and EORTC-H&N35), is compared with the original paper-pen approach in the Quality of Life monitoring of head and neck cancer patients. The Quality of Life informatics platform was designed specifically for this study with a simple and intuitive interface that ensures confidentiality while providing Quality of Life evaluation for all cancer patients. For the Validation Model, the sample selection was random. Fifty-four head and neck cancer patients completed 216 questionnaires (108 using the informatics platform and 108 using the original paper-pen approach) with a one-hour interval in between. Patient preferences and computer experience were registered. Quality of Life informatics platform showed high usability as a user-friendly tool. This informatics platform allows data collection by auto-reply, database construction, and statistical data analysis and also facilitates the automatic listing of the questionnaires. When comparing the approaches (Wilcoxon test by item, percentile distribution and Cronbach's alpha), most of the responses were similar. Most of the patients (53.6%) reported a preference for the software version. The Quality of Life informatics platform has revealed to be a powerful and effective tool, allowing a real time analysis of Quality of Life data. Computer-based quality-of-life monitoring in head and neck cancer patients is essential to get clinically meaningful data that can support clinical decisions, identify potential needs, and support a stepped-care model. This represents a fundamental step for routine Quality of Life implementation in the Oncology Portuguese Institute (IPO-Porto), ORL and C&P department services clinical practice. Finally, we propose a diagram of diagnostic performance, considerating the generalized lack of mycological diagnosis in Portugal, which emphasizes the need for a careful history, focused on quantifying the latency period.
Acta medica portuguesa 12/2011; 24 Suppl 2:347-54. · 0.09 Impact Factor
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ABSTRACT: This study evaluates the influence of clinicopathological characteristics, bacillus Calmette-Guérin (BCG) therapeutic schedule [maintenance (mBCG) or induction (iBCG)], and TNF-α and IL-4 polymorphisms on the outcome of non-muscle-invasive bladder cancer patients treated with BCG.
DNA was extracted from 125 bladder cancer patients treated with BCG; TNF-308G/A and IL4-590C/T polymorphisms were genotyped.
The TNF-308A allele carriers had an increased risk of developing multiple tumors (OR: 2.80, p = 0.031). However, IL4-590 T carriers also had an increased risk of developing multiple and carcinoma in situ tumors (OR: 2.52, p = 0.033). For these polymorphisms, no association was found with BCG treatment outcome. When treated with iBCG, patients with multiple tumors had shorter recurrence-free survival (RFS) compared with those with a single tumor (p = 0.004); nevertheless, patients with multifocal tumors have improved RFS when treated with mBCG.
Overall, the results suggest that multiple tumors and/or carcinoma in situ development are associated with the IL4-590C/T and TNF-308G/A polymorphisms, and emphasize the effectiveness of the mBCG schedule.
Urologia Internationalis 11/2011; 87(4):457-63. · 0.99 Impact Factor
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ABSTRACT: We recently reported the expression of an estradiol-like molecule by a trematode parasite Schistosoma haematobium. We further established that this estradiol-like molecule is an antagonist of estradiol, repressing the transcriptional activity of the estrogen receptor (ER) in estrogen-responsive MCF7 cells and also that S. haematobium total antigen (Sh) contains estrogenic molecules detected by mass spectrometry. In the present study, we used HCV29 cells, a cell line derived from normal urothelial cells, as well as an in vivo model to evaluate the expression of ER in the bladders of Sh-instilled animals. We show that, similarly to MCF7 cells, Sh down-regulates the transcriptional activity of ER in HCV29 cells and also in the bladders of Sh-treated mice. The antiestrogenic activity of the S. haematobium extract and its repressive role in ER could have implications in the carcinogenic process in bladders with S. haematobium infection.
Oncology Reports 11/2011; 27(2):356-62. · 1.84 Impact Factor
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ABSTRACT: Bracken (Pteridium aquilinum) has long been known to cause cancer in farm and laboratory animals. Ptaquiloside, a norsesquiterpene glycoside found in bracken, is considered its main carcinogenic toxin and is capable of inducing tumours in a variety of organ systems, but especially in the urinary bladder, depending on the animal species, the administration route employed and the duration of exposure. In the present study, 12 male CD-1 mice were intraperitoneally administered with 0.5 mg ptaquiloside weekly for 15 weeks, followed by 15 weeks without any treatment. Twelve animals used as controls were administered the vehicle solution (phosphate buffered saline). Two exposed animals died during the experimental work. On necropsy, blood and tissue samples (brain, eyes, thymus, heart, lungs, liver, digestive system, spleen, bladder, kidney, adrenal gland, urinary bladder, sexual accessory glands, testes, muscle, skin and femur) were collected for histological analysis. Leukograms were prepared from blood smears and total WBC counts obtained with a Neubauer chamber. Flow cytometry was used to assess blood T-(CD3(+)) and B-(CD19(+))-lymphocytes, medullary granulocytic (CD11b(+)/Ly-6G(-), CD11b(+)/Ly-6G(+)) and lymphocytic (CD19(+)/IgM(-), CD19+/IgM(+)) populations and thymic lymphoid (CD4(+), CD8(+), CD4(+)/CD8(+)) populations. Lymphoproliferative lesions were analysed immunohistochemically using antibodies against CD45R and CD3. All of the 10 surviving mice developed a lymphoproliferative malignancy. Lymphoproliferative disease was characterized by multifocal B-(CD45(+)/CD3(-))-lymphocytic renal (10/10 animals) and hepatic (2/10 animals) invasion, splenic white pulp hyperplasia (10/10) together with a significant increase in circulating B-(CD19(+))-lymphocytes and the appearance of circulating dysplastic lymphoid cells. Eight out of 10 ptaquiloside-exposed animals developed urothelial dysplasia (six low-grade dysplasia and two high-grade dysplasia). No lesions were detected in control mice. These results show that ptaquiloside is capable of inducing malignant transformation in mice and provide an in-depth characterisation of lymphoproliferative lesions. Furthermore, the urinary bladder is shown to be a target organ for this toxin in mice as well as in other animal species.
Toxicon 09/2011; 58(6-7):543-9. · 2.51 Impact Factor
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ABSTRACT: The Epstein-Barr virus (EBV) persists for long periods in latent state inside B-lymphocytes after primary infections, and reactivation usually occurs associated to immunosuppression conditions of the host. Recently, the detection of EBV DNA in circulation has been suggested as a predictor marker for the development of EBV related malignancies.
The aim of our study was to characterize the frequency of circulating EBV in healthy individuals (n=508) from the North region of Portugal, using peripheral blood samples. Detection was performed by Nested-PCR which amplifies a fragment from the BamHIW region of the EBV genome.
Our results revealed an overall frequency of 37.2% positive cases for EBV in circulation, with distinct distribution according to genre (39.7% in male individuals and 33.2% in females). We also found that EBV is more frequent in individuals with more than 56 years old compared to individuals with less than 56 years old (p=0.032; RR=1.41), mainly in the male group (p=0.024; OR=1.51).
This is the first study which characterizes the frequency of EBV in circulation in healthy donors from the Northern Region of Portugal, revealing increased frequency of EBV in circulation in healthy individuals with differences depending on gender or age. Further studies are required to analyze the role of circulating EBV in the definition of susceptibilities to EBV associated diseases.
Acta medica portuguesa 09/2011; 24(5):707-12. · 0.09 Impact Factor
