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de Oliveira C.M.,University of Sao Paulo | Fregnani J.H.T.G.,Nucleo de Apoio ao Pesquisador do Hospital de Cancer de Barretos | Carvalho J.P.,University of Sao Paulo | Longatto-Filho A.,Molecular Oncology Research Center | And 3 more authors.
BMC Cancer | Year: 2013

Background: Invasive cervical cancer is the second most common malignant tumor affecting Brazilian women. Knowledge on Human Papillomavirus (HPV) genotypes in invasive cervical cancer cases is crucial to guide the introduction and further evaluate the impact of new preventive strategies based on HPV. We aimed to provide updated comprehensive data about the HPV types' distribution in patients with invasive cervical cancer.Methods: Fresh tumor tissue samples of histologically confirmed invasive cervical cancer were collected from 175 women attending two cancer reference hospitals from São Paulo State: ICESP and Hospital de Câncer de Barretos. HPV detection and genotyping were performed by the Linear Array HPV Genotyping Test (Roche Molecular Diagnostics, Pleasanton,USA).Results: 170 out of 172 valid samples (99%) were HPV DNA positive. The most frequent types were HPV16 (77.6%), HPV18 (12.3%), HPV31 (8.8%), HPV33 (7.1%) and HPV35 (5.9%). Most infections (75%) were caused by individual HPV types. Women with adenocarcinoma were not younger than those with squamous cell carcinoma, as well, as women infected with HPV33 were older than those infected by other HPV types. Some differences between results obtained in the two hospitals were observed: higher overall prevalence of HPV16, absence of single infection by HPV31 and HPV45 was verified in HC-Barretos in comparison to ICESP patients.Conclusions: To our knowledge, this is one of the largest studies made with fresh tumor tissues of invasive cervical cancer cases in Brazil. This study depicted a distinct HPV genotype distribution between two centers that may reflect the local epidemiology of HPV transmission among these populations. Due to the impact of these findings on cervical cancer preventive strategies, extension of this investigation to routine screening populations is warranted. © 2013 de Oliveira et al.; licensee BioMed Central Ltd. Source


Campanella N.C.,Molecular Oncology Research Center | de Oliveira A.T.,Barretos Cancer Hospital | Scapulatempo-Neto C.,Molecular Oncology Research Center | Guimaraes D.P.,Molecular Oncology Research Center | And 2 more authors.
Recent Patents on Anti-Cancer Drug Discovery | Year: 2013

Gastrointestinal stromal tumors (GISTs) owe their development to the activating mutations in mast/stem cell growth factor receptor (KIT) or platelet-derived growth factor receptor A (PDGFRA) oncogenes. Both these KIT and PDGFRA oncogenes are members of the type III transmembrane receptor tyrosine kinase family that stimulates intracellular signaling pathways controlling cell proliferation, adhesion, apoptosis, survival, and differentiation. The presence and type of KIT/PDGFRA mutations help to predict the imatinib mesylate therapy, a selective tyrosine kinase inhibitor. Moreover, there is reported a small proportion of wild-type GISTs for both KIT and PDGFRA genes, and tumors more often acquire secondary mutations on KIT, that results into imatinib resistance. New patents to the GISTs imatinib resistant have recently been introduced. At present, sunitinib, is prescribed as second line therapy for patients with imatinibresistant or imatinib-intolerant GIST, and a number of other drugs, such as masitinib and valatinib, are in the pipeline. The present research focuses on GISTs diagnostic, prognostic and therapeutic biomarkers and addresses the development of novel patents for the treatment of these patients. © 2013 Bentham Science Publishers. Source


Yoshimoto M.,Queens University | Ding K.,Queens University | Sweet J.M.,University of Toronto | Ludkovski O.,University of Toronto | And 7 more authors.
Modern Pathology | Year: 2013

Prostatic adenocarcinoma is an epithelial malignancy characterized by marked histological heterogeneity. It most often has a multifocal distribution within the gland, and different Gleason grades may be present within different foci. Data from our group and others have shown that the genomic deletion of the phosphatase and tensin homolog deleted on chromosome 10 (PTEN) tumor suppressor gene and the disruption of the ETS gene family have a central role in prostate cancer and are likely to be associated with Gleason grade. In this study, prostate cancer samples were systematically analyzed to determine whether there was concordance between PTEN losses and TMPRSS2-ERG fusion rearrangements, within or between foci in multifocal disease, using well-annotated tissue microarrays (TMAs) consisting of 724 cores derived from 142 radical prostatectomy specimens. Three-color fluorescence in situ hybridization analysis of both the PTEN deletion and the TMPRSS2-ERG fusion was used to precisely map genetic heterogeneity, both within and between tumor foci represented on the TMA. PTEN deletion was observed in 56 of 134 (42%) patients (hemizygous=42 and homozygous=14). TMPRSS2-ERG fusion was observed in 63 of 139 (45%) patients. When analyzed by Gleason pattern for a given TMA core, PTEN deletions were significantly associated with Gleason grades 4 or 5 over grade 3 (P<0.001). Although TMPRSS2-ERG fusions showed a strong relationship with PTEN deletions (P=0.007), TMPRSS2-ERG fusions did not show correlation with Gleason grade. The pattern of genetic heterogeneity of PTEN deletion was more diverse than that observed for TMPRSS2-ERG fusions in multifocal disease. However, the marked interfocal discordance for both TMPRSS2-ERG fusions and PTEN deletions was consistent with the concept that multiple foci of prostate cancer arise independently within the same prostate, and that individual tumor foci can have distinct patterns of genetic rearrangements. © 2013 USCAP, Inc. All rights reserved. Source


Paugh B.S.,University of Tennessee Health Science Center | Zhu X.,University of Tennessee Health Science Center | Qu C.,University of Tennessee Health Science Center | Endersby R.,University of Western Australia | And 11 more authors.
Cancer Research | Year: 2013

The outcome for children with high-grade gliomas (HGG) remains dismal, with a 2-year survival rate of only 10% to 30%. Diffuse intrinsic pontine glioma (DIPG) comprise a subset of HGG that arise in the brainstem almost exclusively in children. Genome-wide analyses of copy number imbalances previously showed that plateletderived growth factor receptor a (PDGFRA) is the most frequent target of focal amplification in pediatric HGGs, including DIPGs. To determine whether PDGFRA is also targeted by more subtle mutations missed by copy number analysis, we sequenced all PDGFRA coding exons from a cohort of pediatric HGGs. Somatic-activating mutations were identified in 14.4% (13 of 90) of nonbrainstem pediatric HGGs and 4.7% (2 of 43) of DIPGs, including missense mutations and in-frame deletions and insertions not previously described. Forty percent of tumors with mutation showed concurrent amplification, whereas 60% carried heterozygous mutations. Six different mutations impacting different domains all resulted in ligand-independent receptor activation that was blocked by small molecule inhibitors of PDGFR. Expression of mutants in p53-null primary mouse astrocytes conferred a proliferative advantage in vitro and generated HGGs in vivo with complete penetrance when implanted into brain. The gene expression signatures of these murine HGGs reflected the spectrum of human diffuse HGGs. PDGFRA intragenic deletion of exons 8 and 9 were previously shown in adult HGG, but were not detected in 83 nonbrainstem pediatric HGG and 57 DIPGs. Thus, a distinct spectrum of mutations confers constitutive receptor activation and oncogenic activity to PDGFRa in childhood HGG. © 2013 AACR. Source


Louvanto K.,McGill University | Louvanto K.,University of Turku | Rautava J.,University of Turku | Syrjanen K.,Molecular Oncology Research Center | And 2 more authors.
Clinical Microbiology and Infection | Year: 2014

Persistence of high-risk (HR-) human papillomavirus (HPV) infection of the uterine cervix increases the risk of cervical cancer. Oral HPV infections are among potential covariates of long-term genotype-specific persistent cervical HR-HPV infections. It is not known whether this persistence reflects inability of the host to reject HPV infections in general. A case-control setting was designed to estimate the covariates of long-term persistent cervical HR-HPV infections using multivariate generalized estimating equation (GEE) models. HPV was detected with PCR using GP05+/GP06+-primers and genotyped for 24 HPVs with a Multimetrix-kit. The cases (n = 43) included women who had genotype-specific persistent cervical HR-HPV infection for at least 24 months (24M+) and controls were women who tested repeatedly HPV-negative in their cervical samples (n = 52). These women represent a sub-cohort of the Finnish Family HPV Study. The cases differed significantly from the HPV-negative controls in several aspects: they were younger, had a longer mean time to incident oral HPV infection (40.7 versus 23.6 months), longer duration of oral HPV persistence (38.4 versus 14.1 months), and longer time to clearance of their oral HPV infection (50.0 versus 28.2 months). In multivariate GEE analysis, the second pregnancy during the follow up was the only independent predictor with significant protective effect against 24M+ persistent cervical HR-HPV infections, OR of 0.15 (95% CI 0.07-0.34). To conclude, long-term persistent cervical HR-HPV infections are associated with a prolonged clearance of oral HR-HPV infections while new pregnancy protects against persistent cervical HR-HPV infections. © 2014 European Society of Clinical Microbiology and Infectious Diseases. Source

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