77 research outputs found
Gene-specific methylation profiles in BRCA-mutation positive and BRCA-mutation negative male breast cancers
Male breast cancer (MBC) is a rare disease. Due to its rarity, MBC research and clinical approach are mostly based upon data derived from female breast cancer (FBC). Increasing evidence indicate that on molecular level MBC may be an heterogeneous disease different from FBC. In order to investigate whether epigenetic signatures could define molecular subgroups of MBCs, we performed promoter methylation analysis of genes involved in signal transduction and hormone signalling in BRCA1/2 mutation-positive and -negative MBCs. We examined 69 MBCs, paired blood samples, and 15 normal tissues for promoter methylation of hTERT, ESR1, RASSF1, AR, MYC and WNT1 genes. MBCs showed higher gene promoter methylation levels compared to paired blood and normal breast samples. Significantly higher RASSF1 methylation levels were observed in association with BRCA1/2 mutations, HER2 expression and high tumor grade. Significantly higher AR methylation levels were observed in BRCA1/2 wild-type cases and higher WNT1 methylation levels in PR negative cases. Overall, our results indicate that alterations in gene methylation profiles are common in MBC and that methylation pattern of tumor-associated genes may allow for the identification of MBC molecular subgroups, that could have implications in clinical management of MBC patients
Eicosapentaenoic acid induces DNA demethylation in carcinoma cells through a TET1-dependent mechanism
In cancer cells, global genomic hypomethylation is found together with localized hypermethylation of CpG islands within the promoters and regulatory regions of silenced tumor suppressor genes. Demethylating agents may reverse hypermethylation, thus promoting gene re-expression. Unfortunately, demethylating strategies are not efficient in solid tumor cells. DNA demethylation is mediated by ten-eleven translocation enzymes (TETs). They sequentially convert 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC), which is associated with active transcription; 5-formylcytosine; and finally, 5-carboxylcytosine. Although α-linolenic acid, eicosapentaenoic acid (EPA), and docosahexaenoic acid, the major n-3 polyunsaturated fatty acids, have anti-cancer effects, their action, as DNA-demethylating agents, has never been investigated in solid tumor cells. Here, we report that EPA demethylates DNA in hepatocarcinoma cells. EPA rapidly increases 5hmC on DNA, inducing p21Waf1/Cip1 gene expression, which slows cancer cell-cycle progression. We show that the underlying molecular mechanism involves TET1. EPA simultaneously binds peroxisome proliferator-activated receptor γ (PPARγ) and retinoid X receptor α (RXRα), thus promoting their heterodimer and inducing a PPARγ-TET1 interaction. They generate a TET1-PPARγ-RXRα protein complex, which binds to a hypermethylated CpG island on the p21 gene, where TET1 converts 5mC to 5hmC. In an apparent shuttling motion, PPARγ and RXRα leave the DNA, whereas TET1 associates stably. Overall, EPA directly regulates DNA methylation levels, permitting TET1 to exert its anti-tumoral function.-Ceccarelli, V., Valentini, V., Ronchetti, S., Cannarile, L., Billi, M., Riccardi, C., Ottini, L., Talesa, V. N., Grignani, F., Vecchini, A., Eicosapentaenoic acid induces DNA demethylation in carcinoma cells through a TET1-dependent mechanism
Smoking and FGFR2 rs2981582 variant independently modulate male breast cancer survival: A population-based study in Tuscany, Italy
Aim: Male breast cancer (MBC) is a rare disease and recommendations for its clinical management are often extrapolated from those for female breast cancer, even if breast cancer (BC) has different characteristics in the two sexes. The purpose of this study was to assess the influence of several individual characteristics including clinico-pathological, lifestyle and genetic factors on overall survival (OS) of a relatively large and well characterized population-based series of 166 MBCs enrolled in Tuscany. Methods: We genotyped MBC cases at BRCA1/2 genes and at 9 candidate BC susceptibility SNPs. Kaplan-Meier method and multivariate Cox regression, adjusted for several individual characteristics were used. To reduce a possible selection bias related to the interval between diagnosis and enrolment of MBC cases into the study, we used the date of blood donation as the date of the start of observation for survival analysis. Results: Only smoking habits had a significant effect on OS at 10 years (for current smokers, HR: 3.34; 95% CI 1.45–7.68; p = 0.004), while lymph node status fell short of reaching statistical significance (for pN positive, HR: 2.07; 95% CI 0.93–4.55; p = 0.07). In the same multivariate analysis we found a significantly higher OS in cases with FGFR2 rs2981582 variant in the dominant transmission model (HR: 0.29; 95% CI: 0.13–0.62; p = 0.028). A sensitivity analysis with left truncation showed similar results. Conclusions: Our results may contribute to shed light on factors influencing MBC survival suggesting an important role for cigarette smoking and FGFR2 rs2981582 variant, and provide clues for better patient management
MiRNAs as Potential Prognostic Biomarkers for Metastasis in Thin and Thick Primary Cutaneous Melanomas.
Background/Aim: The identification of novel
prognostic biomarkers for melanoma metastasis is essential
to improve patient outcomes. To this aim, we characterized
miRNA expression profiles in relation to metastasis in
melanoma and correlated miRNAs expression with clinicalpathological factors. Materials and Methods: MiR-145-5p,
miR-150-5p, miR-182-5p, miR-203-3p, miR-205-5p and miR211-5p expression levels were analyzed in primary cutaneous
melanomas, including thin and thick melanomas, and in
melanoma metastases by quantitative Real-Time PCR.
Results: A significantly lower miR-205-5p expression was
found in metastases compared to primary melanomas.
Furthermore, a progressive down-regulation of miR-205-5p
expression was observed from loco-regional to distant
metastasis. Significantly lower miR-145-5p and miR-203-3p
expression levels were found in cases with Breslow thickness
>1 mm, high Clark level, ulceration and mitotic rate
≥1/mm2. Conclusion: Our findings point to miR-205-5p as
potential biomarker of distant metastases and to miR-145-5p
and miR-203-3p as markers of aggressiveness in melanoma
Metastases risk in thin cutaneous melanoma: Prognostic value of clinical-pathologic characteristics and mutation profile
Background: A high percentage of patients with thin melanoma (TM), defined as lesions with Breslow thickness ≤1 mm, presents excellent long-term survival, however, some patients develop metastases. Existing prognostic factors cannot reliably differentiate TM patients at risk for metastases. Objective: We aimed at characterizing the clinical-pathologic and mutation profile of metastatic and not-metastatic TM in order to distinguish lesions at risk of metastases. Methods: Clinical-pathologic characteristics were recorded for the TM cases analyzed. We used a Next Generation Sequencing (NGS) multi-gene panel to characterize TM for multiple somatic mutations. Results: A statistically significant association emerged between the presence of metastases and Breslow thickness ≥0.6 mm (p=0.003). None of TM with lymph-node involvement had Breslow thickness < 0.6 mm. Somatic mutations were identified in 19 of 21 TM analyzed (90.5%). No mutations were observed in two not-metastatic cases with the lowest Breslow thickness (≤0.4 mm), whereas mutations in more than one gene were detected in one metastatic case with the highest Breslow thickness (1.00 mm). Conclusion: Our study indicates Breslow thickness ≥0.6 mm as a valid prognostic factor to distinguish TM at risk for metastases
Desarrollo urbano integral y Centro de nutrición comunitario
Este trabajo presenta una propuesta para un desarrollo urbano integral sobre los barrios Nebot, Polo de Desarrollo y San AgustÃn del distrito Colonia Segovia, en el Departamento de Guaymallén.
Dicha propuesta urbana, contempla la construcción de un Centro de Nutrición Comunitario, el cual busca fortalecer la unión de las comunidades de los tres barrios inmersos en condiciones vulnerables, abordando de manera integral, la problemática nutricional que presenta el sector.
El mencionado centro, se expresa como un espacio multiplicador de iniciativas barriales, que acompaña los procesos de mejoras familiares y comunitarias.Fil: Arias, Camila Aylén. Universidad Nacional de Cuyo. Facultad de IngenierÃa.Fil: Valentini, Virginia Andrea. Universidad Nacional de Cuyo. Facultad de IngenierÃa.Fil: Virdó Lauricella, Carolina Inés. Universidad Nacional de Cuyo. Facultad de IngenierÃa
PO-076 Molecular analysis of BRCA-negative breast and/or ovarian cancer families by multigene panel testing
Introduction About 5%–10% of the hereditary breast and/or ovarian cancer (BC/BOC) is associated with an autosomal dominant genetic susceptibility due to highly penetrant mutations of the BRCA1/2 genes. In particular, BRCA1/2 gene mutations are found in 25%–30% of the BC families subjected to genetic testing. These numbers suggest the possible involvement of other genes in BC/BOC genetic predisposition and a fraction of these cases remains to be assigned to specific genetic factors. Here we report on the application of the NGS multigene panel to a group of BRCA1/2 mutation negative BC/BOC cases, in order to identify germline mutations that could further explain BC/BOC genetic susceptibility. Material and methods We selected a group of 27 BRCA1/2 negative BC and BOC families on the basis of a clear dominant inheritance pattern and/or a moderate/high BRCAPro score. We performed a genomic screening by a comprehensive multi-gene custom panel of 29 cancer-related genes, using Ion Torrent platform (Thermo Fisher Scientific). Results and discussions In three cases (11%) we found mutations described as pathogenic (https://www.ncbi.nlm.nih.gov/clinvar/) in ATM, MUTYH and PALB2 genes. In the series analysed, the most frequently altered genes were APC and ATM (15%) but were also identified mutations in MSH6 and TP53 (11%), MUTYH and RAD51B (7%), MRE11, EPCAM, BRIP1, CHEK2, PALB2, BARD1, STK11 and RAD50 (4%). In particular, we found six genomic variants of uncertain significance (VUS) in MSH6, ATM, BRIP1, RAD50 and APC genes; nine genomic variants of conflicting interpretations of pathogenicity in MUTYH, MRE11, TP53, APC, MSH6, CHEK2, EPCAM and ATM genes and eight genomic variants not reported in ClinVar in APC, RAD51B, STK11, TP53, ATM and BARD1 genes predicted deleterious by in silico analysis. Their biological significance and involvement in the development of the pathology is still unknown today. Only six patients were negative for the presence of mutations in the 29 genes analysed. Conclusion Preliminary results of this study suggest that NGS could offer a great contribution to identify the genetic component of susceptibility to BC/BOC and could potentially be used with implications for clinical management and counselling of patients and their families. Moreover, our results suggest that multigene testing approach may benefit appropriately selected patients, especially those with increased risk of BC/BOC development
Somatic alterations of targetable oncogenes are frequently observed in BRCA1/2 mutation negative male breast cancers
Male breast cancer (MBC) is a rare disease. Due to its rarity, MBC research and clinical approach are mostly based upon data derived from its largely known female counterpart. We aimed at investigating whether MBC cases harbor somatic alterations of genes known as prognostic biomarkers and molecular therapeutic targets in female breast cancer.We examined 103 MBC cases, all characterized for germ-line BRCA1/2 mutations, for somatic alterations in PIK3CA, EGFR, ESR1 and CCND1 genes.Pathogenic mutations of PIK3CA were detected in 2% of MBCs. No pathogenic mutations were identified in ESR1 and EGFR. Gene copy number variations (CNVs) analysis showed amplification of PIK3CA in 8.1%, EGFR in 6.8% and CCND1 in 16% of MBCs, whereas deletion of ESR1 was detected in 15% of MBCs. Somatic mutations and gene amplification were found only in BRCA1/2 mutation negative MBCs.Significant associations emerged between EGFR amplification and large tumor size (T4), ER-negative and HER2-positive status, between CCND1 amplification and HER2-positive and MIB1-positive status, and between ESR1 deletion and ER-negative status.Our results show that amplification of targetable oncogenes is frequent in BRCA1/2 mutation negative MBCs and may identify MBC subsets characterized by aggressive phenotype that may benefit from potential targeted therapeutic approaches
Contribution of MUTYH variants to male breast cancer risk: results from a multicenter study in Italy
Inherited mutations in BRCA1, and, mainly, BRCA2 genes are associated with increased risk of male breast cancer (MBC). Mutations in PALB2 and CHEK2 genes may also increase MBC risk. Overall, these genes are functionally linked to DNA repair pathways, highlighting the central role of genome maintenance in MBC genetic predisposition. MUTYH is a DNA repair gene whose biallelic germline variants cause MUTYH-associated polyposis (MAP) syndrome. Monoallelic MUTYH variants have been reported in families with both colorectal and breast cancer and there is some evidence on increased breast cancer risk in women with monoallelic variants. In this study, we aimed to investigate whether MUTYH germline variants may contribute to MBC susceptibility. To this aim, we screened the entire coding region of MUTYH in 503 BRCA1/2 mutation negative MBC cases by multigene panel analysis. Moreover, we genotyped selected variants, including p.Tyr179Cys, p.Gly396Asp, p.Arg245His, p.Gly264Trpfs*7, and p.Gln338His, in a total of 560 MBC cases and 1,540 male controls. Biallelic MUTYH pathogenic variants (p.Tyr179Cys/p.Arg241Trp) were identified in one MBC patient with phenotypic manifestation of adenomatous polyposis. Monoallelic pathogenic variants were identified in 14 (2.5%) MBC patients, in particular, p.Tyr179Cys was detected in seven cases, p.Gly396Asp in five cases, p.Arg245His and p.Gly264Trpfs*7 in one case each. The majority of MBC cases with MUTYH pathogenic variants had family history of cancer including breast, colorectal, and gastric cancers. In the case-control study, an association between the variant p.Tyr179Cys and increased MBC risk emerged by multivariate analysis [odds ratio (OR) = 4.54; 95% confidence interval (CI): 1.17-17.58; p = 0.028]. Overall, our study suggests that MUTYH pathogenic variants may have a role in MBC and, in particular, the p.Tyr179Cys variant may be a low/moderate penetrance risk allele for MBC. Moreover, our results suggest that MBC may be part of the tumor spectrum associated with MAP syndrome, with implication in the clinical management of patients and their relatives. Large-scale collaborative studies are needed to validate these findings
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