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INTRODUCTION: Pancreatic cancer (PC) surveillance of high-risk individuals (HRI) is becoming more common worldwide, aiming at anticipating PC diagnosis at a preclinical stage. In 2015, the Italian Registry of Families at Risk of Pancreatic Cancer was created. We aimed to assess the prevalence and incidence of pancreatic findings, oncological outcomes, and harms 7 years after the Italian Registry of Families at Risk of Pancreatic Cancer inception, focusing on individuals with at least a 3-year follow-up or developing events before. METHODS: HRI (subjects with a family history or mutation carriers with/without a family history were enrolled in 18 centers). They underwent annual magnetic resonance with cholangiopancreatography or endoscopic ultrasound (NCT04095195). RESULTS: During the study period (June 2015-September 2022), 679 individuals were enrolled. Of these, 524 (77.2%) underwent at least baseline imaging, and 156 (29.8%) with at least a 3-year follow-up or pancreatic malignancy/premalignancy-related events, and represented the study population. The median age was 51 (interquartile range 16) years. Familial PC cases accounted for 81.4% of HRI and individuals with pathogenic variant for 18.6%. Malignant (n = 8) and premalignant (1 PanIN3) lesions were found in 9 individuals. Five of these 8 cases occurred in pathogenic variant carriers, 4 in familial PC cases (2 tested negative at germline testing and 2 others were not tested). Three of the 8 PC were stage I. Five of the 8 PC were resectable, 3 Stage I, all advanced cases being prevalent. The 1-, 2-, and 3-year cumulative hazard of PC was 1.7%, 2.5%, and 3%, respectively. Median overall and disease-free survival of patients with resected PC were 18 and 12 months (95% CI not computable). Considering HRI who underwent baseline imaging, 6 pancreatic neuroendocrine neoplasms (1 resected) and 1 low-yield surgery (low-grade mixed-intraductal papillary mucinous neoplasm) were also reported. DISCUSSION: PC surveillance in a fully public health care system is feasible and safe, and leads to early PC or premalignant lesions diagnoses, mostly at baseline but also over time.
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Carcinoma Ductal Pancreático , Carcinoma , Neoplasias Pancreáticas , Humanos , Adolescente , Estudos Prospectivos , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/epidemiologia , Pâncreas/patologia , Imageamento por Ressonância Magnética , Carcinoma Ductal Pancreático/patologiaRESUMO
Abstract. Objective: The aim of this study is to evaluate male awareness of developing prostate cancer (PCa) in families with germline DNA-repair genes (DRG) variants. Materials and methods: Data were collected from a prospective, monocentric cohort study. The study was conducted in a university hospital with a multidisciplinary approach to the patient (collaboration of the Departments of Oncology, Urology, Pathology, Radiology, and Medical Genetics Laboratory). We recruited healthy males, relatives of families of women with breast or ovarian cancer who tested positive for pathogenic variants (PVs) or likely pathogenic variants (LPVs) in DRGs. A dedicated PCa screening was designed and offered to men aged 35 to 69 years, based on early visits with digital rectal examination (DRE), prostate health index (PHI) measurement, multiparametric magnetic resonance imaging (mpMRI) and, if necessary, targeted/systematic prostate biopsies. The primary endpoint was to evaluate the willingness of healthy men from families with a DRG variants detected in female relatives affected with breast and/or ovarian cancer to be tested for the presence of familial PVs. The secondary endpoints were the acceptance to participate if resulted positive and compliance with the screening programme. Results: Over 1256 families, of which 139 resulted positive for PVs in DRGs, we identified 378 'healthy' men aged between 35 and 69 years old. Two hundred sixty-one (69.0%) refused to be tested for DRG variants, 66 (17.5%) declared to have been previously tested, and 51 (13.5%) males were interested to be tested. Between those previously tested and those who accepted to be tested, 62 (53.0%) were positive for a DRG variant, and all of them accepted to participate in the subsequent surveillance steps. The main limitation is that is a single-centre study and a short follow-up. Conclusions: All men tested positive for a DRG variants agreed to go under the surveillance scheme. However, only 31% of 'men at risk' (i.e., relative of a DRG variant carrier) expressed their willingness to be tested for the familial DRG variant. This observation strongly supports the urgent need to implement awareness of genetic risk for PCa within the male population.
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We investigate the prevalence of germline mutations in cancer predisposition genes in patients with pancreatic ductal adenocarcinoma (PDAC) or suspected related hereditary syndromes. METHODS: we enrolled for NGS with an Illumina TrueSight Cancer panel comprising 19 CPGs and 113 consecutive subjects referred to cancer genetic clinics for metastatic PDAC, early onset PDAC, suspected hereditary syndrome, or positive family history. RESULTS: Overall, 23 (20.1%) subjects were carriers of 24 pathogenetic variants (PVs). We found 9 variants in BRCA2 (37.5%), 6 in CDKN2A (25%), 3 in ATM (12.5%), 2 in BRCA1 (8.3%), 1 in CHEK2 (4.1%), 1 in PALB2 (4.1%), 1 in MITF (4.1%), and 1 in FANCM (4.1%). A double PV (BRCA1 plus BRCA2) was found in 1 subject. We observed a nearly 30% (16/55) mutational rate in the subgroup of subjects tested for the suspected syndromes (PDAC and other synchronous or metachronous tumors or an indicative family history), and the frequency was significantly higher than that in patients with only metastatic PDAC (p = 0.05). In our cohort, 39 variants of unknown significance (VUS) were identified, most of which (16/39, 41%) in genes belonging to the Lynch syndrome spectrum. CONCLUSION: A clinically relevant proportion of pancreatic cancer is associated with mutations in known predisposition genes. Guidelines instructing on an adequate selection for accessing genetic testing are eagerly needed. The heterogeneity of mutations identified in this study reinforces the value of using a multiple-gene panel in pancreatic cancer.
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Introdução: O objetivo deste estudo é identificar a frequência de exames citológicos de colo uterino alterados e sua relação com a infecção pelo Papiloma Vírus Humano (HPV) e neoplasias. Métodos: Foram estudadas mulheres residentes em zona urbana, que fizeram exame citopatológico entre 2015 e 2017, com registros no Sistema de Informações do Câncer. Resultados: Foram realizados 25.323 exames citopatológicos, reunindo 815 alterações (3,2%). A faixa etária mais acometida foi entre 30-40 anos. A principal alteração encontrada foi "ASC-US" (431 casos 52,8%). A Lesão Intraepitelial de Baixo Grau, que compreende o efeito citopático pelo HPV e neoplasia intraepitelial cervical Grau I, foi encontrada em 164 casos (20,1%). Após exame de colposcopia, 181 pacientes realizaram biópsia, sendo mais prevalente "NIC I com Alterações Compatíveis com Ação pelo HPV" (21,5%). Conclusão: Elevada prevalência de alterações que podem evoluir para neoplasias de colo uterino, com ênfase naquelas sugestivas da presença de HPV em pacientes abaixo de 25 anos.
Introduction: This study aimed to identify the frequency of changes on cervix cytopathological exams and its relationship with Human Papilloma Virus (HPV) infection and neoplasms. Methods: Women living in the urban area who underwent cytopathological examination from 2015 to 2017 were assessed, based on records from the Cancer Information System. Results: A total of 25,323 cytopathological exams were performed, reporting 815 changes (3.2%). The most affected age group was from 30 to 40 years. The most frequent change was "ASC-US" (431 cases 52.8%). Low-grade intraepithelial lesion, which encompasses the cytopathic effect of HPV and cervical intraepithelial neoplasm grade I, was found in 164 cases (20.1%). After being examined by colposcopy, 181 patients underwent biopsy, whose most prevalent finding was "grade I CIN with Changes Compatible With HPV Action" (21.5%). Conclusion: There was a high prevalence of changes that can evolve to uterine cervical neoplasms, with emphasis on those suggestive of presence of HPV in patients younger than 25 years.
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Colo do ÚteroRESUMO
The prevalence and spectrum of germline mutations in BRCA1 and BRCA2 have been reported in single populations, with the majority of reports focused on White in Europe and North America. The Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) has assembled data on 18,435 families with BRCA1 mutations and 11,351 families with BRCA2 mutations ascertained from 69 centers in 49 countries on six continents. This study comprehensively describes the characteristics of the 1,650 unique BRCA1 and 1,731 unique BRCA2 deleterious (disease-associated) mutations identified in the CIMBA database. We observed substantial variation in mutation type and frequency by geographical region and race/ethnicity. In addition to known founder mutations, mutations of relatively high frequency were identified in specific racial/ethnic or geographic groups that may reflect founder mutations and which could be used in targeted (panel) first pass genotyping for specific populations. Knowledge of the population-specific mutational spectrum in BRCA1 and BRCA2 could inform efficient strategies for genetic testing and may justify a more broad-based oncogenetic testing in some populations.
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Proteína BRCA1/genética , Proteína BRCA2/genética , Internacionalidade , Mutação/genética , Bases de Dados Genéticas , Família , Geografia , HumanosRESUMO
Most common breast cancer susceptibility variants have been identified through genome-wide association studies (GWAS) of predominantly estrogen receptor (ER)-positive disease. We conducted a GWAS using 21,468 ER-negative cases and 100,594 controls combined with 18,908 BRCA1 mutation carriers (9,414 with breast cancer), all of European origin. We identified independent associations at P < 5 × 10-8 with ten variants at nine new loci. At P < 0.05, we replicated associations with 10 of 11 variants previously reported in ER-negative disease or BRCA1 mutation carrier GWAS and observed consistent associations with ER-negative disease for 105 susceptibility variants identified by other studies. These 125 variants explain approximately 16% of the familial risk of this breast cancer subtype. There was high genetic correlation (0.72) between risk of ER-negative breast cancer and breast cancer risk for BRCA1 mutation carriers. These findings may lead to improved risk prediction and inform further fine-mapping and functional work to better understand the biological basis of ER-negative breast cancer.
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Proteína BRCA1/genética , Neoplasias da Mama/genética , Predisposição Genética para Doença/genética , Mutação , Polimorfismo de Nucleotídeo Único , Neoplasias da Mama/etnologia , Neoplasias da Mama/metabolismo , Feminino , Predisposição Genética para Doença/etnologia , Estudo de Associação Genômica Ampla/métodos , Heterozigoto , Humanos , Receptores de Estrogênio/metabolismo , Fatores de Risco , População Branca/genéticaRESUMO
NBS1, also known as NBN, plays an important role in maintaining genomic stability. Interestingly, rs2735383 G > C, located in a microRNA binding site in the 3'-untranslated region (UTR) of NBS1, was shown to be associated with increased susceptibility to lung and colorectal cancer. However, the relation between rs2735383 and susceptibility to breast cancer is not yet clear. Therefore, we genotyped rs2735383 in 1,170 familial non-BRCA1/2 breast cancer cases and 1,077 controls using PCR-based restriction fragment length polymorphism (RFLP-PCR) analysis, but found no association between rs2735383CC and breast cancer risk (OR = 1.214, 95% CI = 0.936-1.574, P = 0.144). Because we could not exclude a small effect size due to a limited sample size, we further analyzed imputed rs2735383 genotypes (r2 > 0.999) of 47,640 breast cancer cases and 46,656 controls from the Breast Cancer Association Consortium (BCAC). However, rs2735383CC was not associated with overall breast cancer risk in European (OR = 1.014, 95% CI = 0.969-1.060, P = 0.556) nor in Asian women (OR = 0.998, 95% CI = 0.905-1.100, P = 0.961). Subgroup analyses by age, age at menarche, age at menopause, menopausal status, number of pregnancies, breast feeding, family history and receptor status also did not reveal a significant association. This study therefore does not support the involvement of the genotype at NBS1 rs2735383 in breast cancer susceptibility.
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Neoplasias da Mama/genética , Proteínas de Ciclo Celular/genética , MicroRNAs/metabolismo , Proteínas Nucleares/genética , Regiões 3' não Traduzidas , Alelos , Proteína BRCA1/genética , Proteína BRCA2/genética , Sítios de Ligação , Neoplasias da Mama/patologia , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Razão de Chances , Polimorfismo de Nucleotídeo Único , Fatores de RiscoRESUMO
A locus at 19p13 is associated with breast cancer (BC) and ovarian cancer (OC) risk. Here we analyse 438 SNPs in this region in 46,451 BC and 15,438 OC cases, 15,252 BRCA1 mutation carriers and 73,444 controls and identify 13 candidate causal SNPs associated with serous OC (P=9.2 × 10(-20)), ER-negative BC (P=1.1 × 10(-13)), BRCA1-associated BC (P=7.7 × 10(-16)) and triple negative BC (P-diff=2 × 10(-5)). Genotype-gene expression associations are identified for candidate target genes ANKLE1 (P=2 × 10(-3)) and ABHD8 (P<2 × 10(-3)). Chromosome conformation capture identifies interactions between four candidate SNPs and ABHD8, and luciferase assays indicate six risk alleles increased transactivation of the ADHD8 promoter. Targeted deletion of a region containing risk SNP rs56069439 in a putative enhancer induces ANKLE1 downregulation; and mRNA stability assays indicate functional effects for an ANKLE1 3'-UTR SNP. Altogether, these data suggest that multiple SNPs at 19p13 regulate ABHD8 and perhaps ANKLE1 expression, and indicate common mechanisms underlying breast and ovarian cancer risk.
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Alelos , Neoplasias da Mama/genética , Cromossomos Humanos Par 19/genética , Predisposição Genética para Doença , Neoplasias Ovarianas/genética , Polimorfismo de Nucleotídeo Único , Povo Asiático/genética , População Negra/genética , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
Common variants in 94 loci have been associated with breast cancer including 15 loci with genome-wide significant associations (P<5 × 10(-8)) with oestrogen receptor (ER)-negative breast cancer and BRCA1-associated breast cancer risk. In this study, to identify new ER-negative susceptibility loci, we performed a meta-analysis of 11 genome-wide association studies (GWAS) consisting of 4,939 ER-negative cases and 14,352 controls, combined with 7,333 ER-negative cases and 42,468 controls and 15,252 BRCA1 mutation carriers genotyped on the iCOGS array. We identify four previously unidentified loci including two loci at 13q22 near KLF5, a 2p23.2 locus near WDR43 and a 2q33 locus near PPIL3 that display genome-wide significant associations with ER-negative breast cancer. In addition, 19 known breast cancer risk loci have genome-wide significant associations and 40 had moderate associations (P<0.05) with ER-negative disease. Using functional and eQTL studies we implicate TRMT61B and WDR43 at 2p23.2 and PPIL3 at 2q33 in ER-negative breast cancer aetiology. All ER-negative loci combined account for â¼11% of familial relative risk for ER-negative disease and may contribute to improved ER-negative and BRCA1 breast cancer risk prediction.
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Neoplasias da Mama/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Receptores de Estrogênio/genética , Proteína BRCA1/genética , Cromossomos Humanos Par 2/genética , Ciclofilinas/genética , Feminino , Genótipo , Heterozigoto , Humanos , Mutação , Polimorfismo de Nucleotídeo Único , Fatores de Risco , tRNA MetiltransferasesRESUMO
BACKGROUND: Subjects referred to genetic counselling for cancer may have heightened perceptions of illness and death, even though they are healthy and this may cause anxiety and reluctance to follow through with consultation. We investigated such perceptions before and after counselling and genetic testing for cancer in a cohort of Italian women. We sought to understand the situation of the women referred by designing questionnaires administered to women at high risk of breast and/or ovarian cancer (those who had had a pathogenic mutation identified in a family member via diagnostic testing). We also assessed women after the diagnosis of breast cancers, but free of disease, to help determine risks in their families. METHODS: The first questionnaires were administered before initial counselling, and the second were completed within 20 days after the counselling. When a genetic test was proposed, the individual was asked to fill in a third questionnaire; the final questionnaire was administered after the person had received the results of the genetic test. RESULTS: We evaluated 204 subjects. Before counselling, 89 % of the subjects were worried about their risk of disease, 52 % felt "different" because of their personal and family history, and 39 % declared that their life choices were influenced by their fear of cancer. After counselling, 82 % of the subjects felt more relived about their pre-existing fears and stated that this process of being seen in a clinic with genetic expertise had clarified the meaning of disease risk for them, and for 50 %, this experience had positively influenced their life choices. Thirty percentage of the subjects had a positive test; all of them felt safer in being cared for by specifically trained staff. Fifty percentage had a less informative test (e.g. "wild-type" gene found); 84 % of them were not worried by the uncertainty, and overall, 96 % considered counselling to be very useful. CONCLUSION: Candidates for genetic counselling frequently had heightened their perception of being ill, which influenced their ability to make life decisions. Genetic counselling often improves this perception, especially in subjects who have negative tests and this knowledge facilitates their life plans. After testing, most women felt satisfied and safer because of being properly followed by professionally trained and sympathetic staff. In conclusion, knowledge of the real individual risk, the presence of a professional team, and the possibility of entering a programme of controlled screening enable patients rather than living in fear and uncertainty to be less anxious about their state of health and to live with the knowledge that they are doing everything possible to care for themselves, aided by a specialized team, and that, if necessary, they would be able to take part in investigational studies.
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Neoplasias da Mama/psicologia , Aconselhamento Genético/psicologia , Neoplasias Ovarianas/psicologia , Percepção , Inquéritos e Questionários , Ansiedade/epidemiologia , Neoplasias da Mama/genética , Escolaridade , Feminino , Nível de Saúde , Humanos , Itália , Neoplasias Ovarianas/genética , Fatores de RiscoRESUMO
Increasing evidence indicates that common genetic variants may contribute to the heritable risk of breast cancer (BC). In this study, we investigated whether single nucleotide polymorphisms (SNPs), within the 8q24.21 multi-cancer susceptibility region and within BC-associated loci widespread in the genome, may influence the risk of BC in men, and whether they may be associated with specific clinical-pathologic characteristics of male BC (MBC). In the frame of the ongoing Italian Multicenter Study on MBC, we performed a case-control study on 386 MBC cases, including 50 BRCA1/2 mutation carriers, and 1105 healthy male controls, including 197 unaffected BRCA1/2 mutation carriers. All 1491 subjects were genotyped by Sequenom iPLEX technology for a total of 29 susceptibility SNPs. By logistic regression models, we found a significant association with MBC risk for five SNPs: rs1562430 (p=0.002) and rs445114 (p=0.026) both within the 8q24.21 region; rs1011970/9p21.3 (p=0.011), rs614367/11q13.3 (p=0.016) and rs1314913/14q24.1 (p<0.0001). Differences in the distribution of rs614367/11q13.3 genotypes according to oestrogen receptor (ER) status (p=0.006), and of rs1011970/9p21.3 genotypes according to human epidermal growth factor receptor 2 (HER2) status (p=0.002) emerged. Association of rs1011970/9p21.3 risk genotype with HER2+MBC was confirmed by a multivariate analysis. rs1314913/14q24.1 was associated with increased MBC risk in analyses restricted to male BRCA1/2 mutation carriers (p=0.041). In conclusion, we provided the first evidence that the 8q24.21 region is associated with MBC risk. Furthermore, we showed that the SNPs rs1562430/8q24.21 and rs1314913/14q24.1 strongly influence BC risk in men and suggested that the SNP rs1314913/14q24.1 may act as a risk modifier locus in male BRCA1/2 mutation carriers.
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Biomarcadores Tumorais/genética , Neoplasias da Mama Masculina/genética , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 8 , Cromossomos Humanos Par 9 , Polimorfismo de Nucleotídeo Único , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama Masculina/patologia , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Frequência do Gene , Predisposição Genética para Doença , Heterozigoto , Homozigoto , Humanos , Itália , Modelos Lineares , Modelos Logísticos , Masculino , Análise Multivariada , Mutação , Razão de Chances , Fenótipo , Valor Preditivo dos Testes , Fatores de RiscoRESUMO
The identification of founder mutations in cancer predisposing genes is important to improve risk assessment in geographically defined populations, since it may provide specific targets resulting in cost-effective genetic testing. Here, we report the characterization of the BRCA1 c.190T>C (p.Cys64Arg) mutation, mapped to the RING-finger domain coding region, that we detected in 43 hereditary breast/ovarian cancer (HBOC) families, for the large part originating from the province of Bergamo (Northern Italy). Haplotype analysis was performed in 21 families, and led to the identification of a shared haplotype extending over three BRCA1-associated marker loci (0.4 cM). Using the DMLE+2.2 software program and regional population demographic data, we were able to estimate the age of the mutation to vary between 3,100 and 3,350 years old. Functional characterization of the mutation was carried out at both transcript and protein level. Reverse transcriptase-PCR analysis on lymphoblastoid cells revealed expression of full length mRNA from the mutant allele. A green fluorescent protein (GFP)-fragment reassembly assay showed that the p.Cys64Arg substitution prevents the binding of the BRCA1 protein to the interacting protein BARD1, in a similar way as proven deleterious mutations in the RING-domain. Overall, 55 of 83 (66%) female mutation carriers had a diagnosis of breast and/or ovarian cancer. Our observations indicate that the BRCA1 c.190T>C is a pathogenic founder mutation present in the Italian population. Further analyses will evaluate whether screening for this mutation can be suggested as an effective strategy for the rapid identification of at-risk individuals in the Bergamo area.
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Proteína BRCA1/química , Proteína BRCA1/genética , Efeito Fundador , Predisposição Genética para Doença , Mutação/genética , Adulto , Fatores Etários , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Segregação de Cromossomos/genética , Éxons/genética , Família , Feminino , Regulação Neoplásica da Expressão Gênica , Geografia , Proteínas de Fluorescência Verde/metabolismo , Haplótipos/genética , Humanos , Itália , Pessoa de Meia-Idade , Taxa de Mutação , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Ligação Proteica , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Domínios RING Finger , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/metabolismoRESUMO
PURPOSE: Monoallelic germ-line deleterious mutations of PALB2 (partner and localizer of BRCA2) are associated with breast cancer risk and have been found in several populations, with carrier frequencies of ~1-2%. Initially, these mutations were considered to have moderate penetrance, but accumulating evidence now indicates that they are associated with much higher risk. METHODS: In this study, we sequenced the PALB2 coding regions unlinked to BRCA (breast cancer) genes in 575 probands from Italian breast cancer families recruited in Milan. RESULTS: We found 12 carriers (2.1%) of deleterious mutations, and none of the mutations was found in 784 controls collected in Milan. One of these mutations, the c.1027C>T (p.Gln343X), was found to be recurrent in the province of Bergamo in northern Italy, being detected in 6/113 (5.3%) familial breast cancer cases and 2/477 (0.4%) controls recruited in this area (Fisher's exact test: P < 0.01). CONCLUSIONS: Our data provide confirmatory findings that, in the Italian population also, deleterious mutations of PALB2 are relatively frequent predisposing factors for breast cancer and may be associated with high risk of the disease.
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Mutação , Proteínas Nucleares/genética , Proteínas Supressoras de Tumor/genética , População Branca/genética , Alelos , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Estudos de Casos e Controles , Análise Mutacional de DNA , Proteína do Grupo de Complementação N da Anemia de Fanconi , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Itália , Polimorfismo GenéticoRESUMO
Germline inactivation of the E-cadherin gene (CDH1) is associated with hereditary diffuse gastric cancer (HDGC), a rare autosomal dominant syndrome predisposing to both diffuse gastric cancer (DGC) and lobular breast cancer (LBC). We searched for CDH1 germline defects in 32 HDGC Italian probands selected according to international consensus criteria and in 5 selected relatives. We used a series of molecular methods, including: DNA sequencing, multiplex ligation-dependent probe amplification, single-nucleotide primer extension, bisulfite sequencing, reverse-transcription PCR, and bioinformatics tools. We identified pathogenic mutations in 6 out of 32 probands (19%): one truncating and two missense mutations, one large deletion, one allelic expression imbalance and one splicing defect. Three out of six CDH1 constitutive alterations were novel. Our data support the need for a multimethod approach for CDH1 genetic testing, demonstrating that both DNA and RNA analyses are required to increase the detection rate of pathogenic mutations, thus reducing the number of patients without a clear molecular diagnosis. On the whole, our results indicate that not only DGC patients, but also subjects with personal or family history of LBC might benefit from CDH1 genetic testing. Moreover, our findings support the notion that prophylactic gastrectomy should be offered to asymptomatic CDH1 mutation carriers; indeed, while endoscopic analysis with histological examination of random gastric biopsies can miss cancer foci, gastrectomy performed in these subjects always revealed foci of cancer cells.
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Caderinas/genética , Heterogeneidade Genética , Neoplasias Gástricas/genética , Adulto , Desequilíbrio Alélico , Antígenos CD , Neoplasias da Mama/genética , Carcinoma Lobular/genética , Feminino , Deleção de Genes , Mutação em Linhagem Germinativa , Humanos , Itália , Pessoa de Meia-Idade , Linhagem , Regiões Promotoras GenéticasRESUMO
Several unclassified variants (UVs) have been identified in splicing regions of disease-associated genes and their characterization as pathogenic mutations or benign polymorphisms is crucial for the understanding of their role in disease development. In this study, 24 UVs located at BRCA1 and BRCA2 splice sites were characterized by transcripts analysis. These results were used to evaluate the ability of nine bioinformatics programs in predicting genetic variants causing aberrant splicing (spliceogenic variants) and the nature of aberrant transcripts. Eleven variants in BRCA1 and 8 in BRCA2, including 8 not previously characterized at transcript level, were ascertained to affect mRNA splicing. Of these, 16 led to the synthesis of aberrant transcripts containing premature termination codons (PTCs), 2 to the up-regulation of naturally occurring alternative transcripts containing PTCs, and one to an in-frame deletion within the region coding for the DNA binding domain of BRCA2, causing the loss of the ability to bind the partner protein DSS1 and ssDNA. For each computational program, we evaluated the rate of non-informative analyses, i.e. those that did not recognize the natural splice sites in the wild-type sequence, and the rate of false positive predictions, i.e., variants incorrectly classified as spliceogenic, as a measure of their specificity, under conditions setting sensitivity of predictions to 100%. The programs that performed better were Human Splicing Finder and Automated Splice Site Analyses, both exhibiting 100% informativeness and specificity. For 10 mutations the activation of cryptic splice sites was observed, but we were unable to derive simple criteria to select, among the different cryptic sites predicted by the bioinformatics analyses, those actually used. Consistent with previous reports, our study provides evidences that in silico tools can be used for selecting splice site variants for in vitro analyses. However, the latter remain mandatory for the characterization of the nature of aberrant transcripts.
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Genes BRCA1 , Genes BRCA2 , Mutação , Splicing de RNA , Linhagem Celular Transformada , Humanos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Mutations in the BRCA1 gene confer a substantial increase in breast cancer risk, yet routine clinical genetic screening is limited to the coding regions and intron-exon boundaries, precluding the identification of mutations in noncoding and untranslated regions (UTR). As 3'UTR mutations can influence cancer susceptibility by altering protein and microRNA (miRNA) binding regions, we screened the BRCA1 3'UTR for mutations in a large series of BRCA-mutation negative, population and clinic-based breast cancer cases, and controls. Fifteen novel BRCA1 3'UTR variants were identified, the majority of which were unique to either cases or controls. Using luciferase reporter assays, three variants found in cases, c.* 528G>C, c.* 718A>G, and c.* 1271T>C and four found in controls, c.* 309T>C, c.* 379G>A, c.* 823C>T, and c.* 264C>T, reduced 3'UTR activity (P < 0.02), whereas two variants found in cases, c.* 291C>T and c.* 1139G>T, increased 3'UTR activity (P < 0.01). Three case variants, c.* 718A>G, c.* 800T>C, and c.* 1340_1342delTGT, were predicted to create new miRNA binding sites and c.* 1340_1342delTGT caused a reduction (25%, P = 0.0007) in 3'UTR reporter activity when coexpressed with the predicted targeting miRNA, miR-103. This is the most comprehensive identification and analysis of BRCA1 3'UTR variants published to date.
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Regiões 3' não Traduzidas , Proteína BRCA1/genética , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Mutação em Linhagem Germinativa , MicroRNAs/genética , Adulto , Pareamento de Bases , Sequência de Bases , Sítios de Ligação , Estudos de Casos e Controles , Linhagem Celular Tumoral , Sequência Conservada , Análise Mutacional de DNA , Proteínas ELAV , Feminino , Frequência do Gene , Estudos de Associação Genética , Humanos , Conformação de Ácido Nucleico , Polimorfismo de Nucleotídeo Único , Ligação Proteica , Interferência de RNA , RNA Mensageiro/genéticaRESUMO
Host, environmental and genetic factors differently modulate cutaneous melanoma (CM) risk across populations. Currently, the main genetic risk determinants are germline mutations in the major known high-risk susceptibility genes, CDKN2A and CDK4, and variants of the low-risk gene MC1R, which is key in the pigmentation process. This case-control study aimed at investigating the influence of the main host and environmental risk factors and of MC1R variation on CM risk in 390 CDKN2A-negative and 49 CDKN2A-positive Italian individuals. Multivariate analysis showed that MC1R variation, number of nevi and childhood sunburns doubled CM risk in CDKN2A-negative individuals. In CDKN2A-positive individuals, family history of CM and presence of atypical nevi, rather than MC1R status, modified risk (20.75- and 2.83-fold, respectively). Occupational sun exposure increased CM risk (three to sixfold) in both CDKN2A-negative and CDKN2A-positive individuals, reflecting the occupational habits of the Ligurian population and the geographical position of Liguria.
Assuntos
Genes p16 , Melanoma/genética , Exposição Ocupacional/efeitos adversos , Receptor Tipo 1 de Melanocortina/genética , Neoplasias Cutâneas/genética , Luz Solar/efeitos adversos , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Intervalos de Confiança , Feminino , Humanos , Itália , Masculino , Melanoma/etiologia , Pessoa de Meia-Idade , Análise Multivariada , Mutação , Nevo/patologia , Razão de Chances , Fatores de Risco , Neoplasias Cutâneas/etiologia , Queimadura Solar/complicações , Adulto JovemRESUMO
Recently, the number of studies on male breast cancer (MBC) has been increasing. However, as MBC is a rare disease there are difficulties to undertake studies to identify specific MBC subgroups. At present, it is still largely unknown whether BRCA-related breast cancer (BC) in men may display specific characteristics as it is for BRCA-related BC in women. To investigate the clinical-pathologic features of MBC in association with BRCA mutations we established a collaborative Italian Multicenter Study on MBC with the aim to recruit a large series of MBCs. A total of 382 MBCs, including 50 BRCA carriers, were collected from ten Italian Investigation Centres covering the whole country. In MBC patients, BRCA2 mutations were associated with family history of breast/ovarian cancer (p<0.0001), personal history of other cancers (p=0.044) and contralateral BC (p=0.001). BRCA2-associated MBCs presented with high tumor grade (p=0.001), PR-(p=0.026) and HER2+ (p=0.001) status. In a multivariate logistic model BRCA2 mutations showed positive association with personal history of other cancers (OR 11.42, 95% CI 1.79-73.08) and high tumor grade (OR 4.93, 95% CI 1.02-23.88) and inverse association with PR+ status (OR 0.19, 95% CI 0.04-0.92). Based on immunohistochemical (IHC) profile, four molecular subtypes of MBC were identified. Luminal A was the most common subtype (67.7%), luminal B was observed in 26.5% of the cases and HER2 positive and triple negative were represented by 2.1% and 3.7% of tumors, respectively. Intriguingly, we found that both luminal B and HER2 positive subtypes were associated with high tumor grade (p=0.003 and 0.006, respectively) and with BRCA2 mutations (p=0.016 and 0.001, respectively). In conclusion, our findings indicate that BRCA2-related MBCs represent a subgroup of tumors with a peculiar phenotype characterized by aggressive behavior. The identification of a BRCA2-associated phenotype might define a subset of MBC patients eligible for personalized clinical management.
Assuntos
Neoplasias da Mama Masculina/genética , Carcinoma Ductal de Mama/genética , Genes BRCA1 , Genes BRCA2 , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama Masculina/patologia , Carcinoma Ductal de Mama/patologia , Análise Mutacional de DNA , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Breast cancer can be caused by germline mutations in several genes that are responsible for different hereditary cancer syndromes. Some of the genes causing the Fanconi anemia (FA) syndrome, such as BRCA2, BRIP1, PALB2, and RAD51C, are associated with high or moderate risk of developing breast cancer. Very recently, SLX4 has been established as a new FA gene raising the question of its implication in breast cancer risk. This study aimed at answering this question sequencing the entire coding region of SLX4 in 526 familial breast cancer cases from Italy. We found 81 different germline variants and none of these were clearly pathogenic. The statistical power of our sample size allows concluding that in Italy the frequency of carriers of truncating mutations of SLX4 may not exceed 0.6%. Our results indicate that testing for SLX4 germline mutations is unlikely to be relevant for the identification of individuals at risk of breast cancer, at least in the Italian population.