Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 74
Filtrar
1.
PLoS Genet ; 16(12): e1009231, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33332384

RESUMO

PURPOSE: Historically, cancer predisposition syndromes (CPSs) were rarely established for children with cancer. This nationwide, population-based study investigated how frequently children with cancer had or were likely to have a CPS. METHODS: Children (0-17 years) in Denmark with newly diagnosed cancer were invited to participate in whole-genome sequencing of germline DNA. Suspicion of CPS was assessed according to Jongmans'/McGill Interactive Pediatric OncoGenetic Guidelines (MIPOGG) criteria and familial cancer diagnoses were verified using population-based registries. RESULTS: 198 of 235 (84.3%) eligible patients participated, of whom 94/198 (47.5%) carried pathogenic variants (PVs) in a CPS gene or had clinical features indicating CPS. Twenty-nine of 198 (14.6%) patients harbored a CPS, of whom 21/198 (10.6%) harbored a childhood-onset and 9/198 (4.5%) an adult-onset CPS. In addition, 23/198 (11.6%) patients carried a PV associated with biallelic CPS. Seven of the 54 (12.9%) patients carried two or more variants in different CPS genes. Seventy of 198 (35.4%) patients fulfilled the Jongmans' and/or MIPOGG criteria indicating an underlying CPS, including two of the 9 (22.2%) patients with an adult-onset CPS versus 18 of the 21 (85.7%) patients with a childhood-onset CPS (p = 0.0022), eight of the additional 23 (34.8%) patients with a heterozygous PV associated with biallelic CPS, and 42 patients without PVs. Children with a central nervous system (CNS) tumor had family members with CNS tumors more frequently than patients with other cancers (11/44, p = 0.04), but 42 of 44 (95.5%) cases did not have a PV in a CPS gene. CONCLUSION: These results demonstrate the value of systematically screening pediatric cancer patients for CPSs and indicate that a higher proportion of childhood cancers may be linked to predisposing germline variants than previously supposed.


Assuntos
Testes Genéticos/estatística & dados numéricos , Mutação em Linhagem Germinativa , Síndromes Neoplásicas Hereditárias/epidemiologia , Sequenciamento Completo do Genoma/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Masculino , Taxa de Mutação , Síndromes Neoplásicas Hereditárias/genética
2.
Artigo em Inglês | MEDLINE | ID: mdl-32292534

RESUMO

Background: We report the first case of a missense variant in the APC gene that interrupts splicing by creating a new cryptic acceptor site. The variant, c.289G>A, p.(Gly97Arg), is located in exon 3, and qualitative and semi-quantitative RNA splicing analysis reveal that the variant results in skipping of the last 70 nucleotides of the exon, which leads to the introduction of a frameshift and a premature stop codon. Case presentation: The variant was detected in two, apparently unrelated, Danish families with an accumulation of colorectal cancers, colonic adenomas and other cancers. The families both have an attenuated familial adenomatous polyposis phenotype, which is consistent with the association of pathogenic variants in the 5' end of the gene.One variant-carrier also had Caroli Disease and a Caroli Disease associated hepatic mucinous cystadenocarcinoma. This is the first description of a person with both Caroli Disease and a pathogenic APC variant, and although the APC variant is not known to be connected to the development of the hepatic malformations in Caroli Disease, it remains unclear whether the variant could have contributed to the carcinogenesis of the liver tumour. Conclusions: Based on functional and co-segregation data we classify the APC c.289G>A, p.(Gly97Arg) variant as pathogenic (class 5). Our findings emphasize the importance of a functional evaluation of missense variants although located far from the exon-intron boundaries.

3.
J Natl Cancer Inst ; 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32107557

RESUMO

BACKGROUND: The purpose of this study was to estimate precise age-specific tubo-ovarian carcinoma (TOC) and breast cancer (BC) risks for carriers of pathogenic variants in RAD51C and RAD51D. METHODS: We analysed data from 6178 families, 125 with pathogenic variants in RAD51C; and 6690 families, 60 with pathogenic variants in RAD51D. TOC and BC relative and cumulative risks were estimated using complex segregation analysis to model the cancer inheritance patterns in families, while adjusting for the mode of ascertainment of each family. All statistical tests were two-sided. RESULTS: Pathogenic variants in both RAD51C and RAD51D were associated with TOC (RAD51C RR = 7.55, 95%CI:5.60-10.19, p = 5 × 10-40; RAD51D RR = 7.60, 95%CI:5.61-10.30, p = 5 × 10-39) and BC (RAD51C RR = 1.99, 95%CI:1.39-2.85, p = 1.55 × 10-4; RAD51D RR = 1.83, 95%CI:1.24-2.72, p = 0.002). For both RAD51C and RAD51D, there was a suggestion that the TOC RRs increased with age until around age 60 years and decreased thereafter. The estimated cumulative risks of developing TOC to age 80 were 11% (95%CI:6-21%) for RAD51C and 13% (95%CI:7-23%) for RAD51D pathogenic variant carriers. The estimated cumulative risks of developing BC to 80 were 21% (95%CI:15-29%) for RAD51C and 20% (95%CI:14-28%) for RAD51D pathogenic variant carriers. Both TOC and BC risks for RAD51C/D pathogenic variant carriers varied by cancer family history, and could be as high as 32-36% for TOC, for carriers with two first degree relatives diagnosed with TOC; or 44-46% for BC, for carriers with two first degree relatives diagnosed with BC. CONCLUSIONS: These estimates will facilitate the genetic counselling of RAD51C and RAD51D pathogenic variant carriers and justify the incorporation of RAD51C and RAD51D into cancer risk prediction models.

4.
Genet Test Mol Biomarkers ; 23(9): 688-695, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31433215

RESUMO

Background and Aims: Hereditary nonpolyposis colon cancer (HNPCC) and Lynch syndrome (LS) are characterized by defects in the mismatch repair (MMR) system, which protects the integrity of the genome. Pathogenic variants in four MMR genes (MLH1, MSH2, MSH6, and PMS2) are responsible for LS, an autosomal, dominant hereditary disease that occurs with a frequency of 2-5% among all colorectal cancer cases. It has been estimated that ∼2-5% of all pathogenic variants found in the four MMR genes in LS cases are detected in the PMS2 gene. An overview of detected variants is presented here. Materials and Methods: Long-range (LR) PMS2 polymerase chain reaction (PCR) and PMS2 multiplex ligation probe amplification (MLPA) assays were used to detect PMS2 variants in ∼1500 probands. In a subset of the probands, pathogenic PMS2 variants were detected by next-generation sequencing, and all detected variants were confirmed by LR-PCR combined with an MLPA assay. Results: A summary of PMS2 mutation analyses performed on colon cancer patients from molecular diagnostic laboratories in Denmark and Sweden is presented. By screening ∼1500 HNPCC probands, a total of 40 different PMS2 variants were detected in 71 probands (5%); 20 variants were classified as pathogenic (C5), 2 variants as likely pathogenic (C4), 15 variants as variants of unknown significance (VUSs) (C3), 1 variant as likely benign (C2), and 2 variants as benign (C1). In total, 22/71 (31%) of the probands carried a pathogenic sequence variant. Among the probands with isolated loss of pPMS2 expression, the fraction of pathogenic variants was 20/35 (55%). Conclusions: Approximately 5% of the probands found in the Danish and Swedish populations presented here carried a PMS2 variant. In this study, six novel pathogenic variants and seven VUSs are reported.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais/genética , Endonuclease PMS2 de Reparo de Erro de Pareamento/genética , Animais , Células COS , Chlorocebus aethiops , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Análise Mutacional de DNA , Dinamarca , Detecção Precoce de Câncer , Sequenciamento de Nucleotídeos em Larga Escala , Reação em Cadeia da Polimerase Multiplex , Reação em Cadeia da Polimerase , Suécia
5.
Virchows Arch ; 473(3): 329-340, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30069755

RESUMO

Adenoid cystic carcinoma (ACC) is among the most frequent malignancies of the salivary gland, and is notorious for its prolonged clinical course characterized by frequent recurrences often years after initial treatment. No molecular marker has been shown to have independent prognostic value in ACC, including characteristic gene fusions involving MYB, MYBL1, and NFIB. MicroRNA has been shown to be associated with clinical outcome in numerous malignancies, including one study of ACC, warranting further validation of this class of markers in this disease. Here, we investigate the prognostic value of microRNA in two ACC cohorts: a training cohort (n = 64) and a validation cohort (n = 120) with microarray and qPCR. In the training cohort, multivariate analysis of microarray data found high expression of hsa-miR-6835-3p to be associated with reduced recurrence-free survival (RFS) (p = 0.016). Measuring the highest ranking microRNAs identified in survival analysis in the same cohort, qPCR identified high expression of hsa-miR-4676 to be associated with reduced overall survival (OS) and high expression of hsa-mir-1180 to be associated with improved RFS. This was not confirmed in the validation cohort, in which qPCR identified high expression of hsa-mir-21, hsa-mir-181a-2, and hsa-mir-152 to be associated with reduced OS and high expression of hsa-miR-374c to be associated with improved RFS. Interestingly, two distinct subsets of ACC separated in microRNA expression irrespective of gene fusion status, but without significant difference in outcome. Collectively, qPCR identified several microRNAs associated with OS and RFS, and different subsets of ACC separated according to microRNA expression, suggestive of ACC being a heterogeneous group of malignancies in its microRNA profile.


Assuntos
Carcinoma Adenoide Cístico/genética , Fusão Gênica , MicroRNAs/análise , Neoplasias das Glândulas Salivares/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Adenoide Cístico/mortalidade , Carcinoma Adenoide Cístico/patologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias das Glândulas Salivares/mortalidade , Neoplasias das Glândulas Salivares/patologia , Adulto Jovem
6.
Artigo em Inglês | MEDLINE | ID: mdl-31517176

RESUMO

Purpose: To describe a snapshot of international genetic testing practices, specifically regarding the use of multigene panels, for hereditary breast/ovarian cancers. We conducted a survey through the Evidence-Based Network for the Interpretation of Germline Mutant Alleles (ENIGMA) consortium, covering questions about 16 non-BRCA1/2 genes. Methods: Data were collected via in-person and paper/electronic surveys. ENIGMA members from around the world were invited to participate. Additional information was collected via country networks in the United Kingdom and in Italy. Results: Responses from 61 cancer genetics practices across 20 countries showed that 16 genes were tested by > 50% of the centers, but only six (PALB2, TP53, PTEN, CHEK2, ATM, and BRIP1) were tested regularly. US centers tested the genes most often, whereas United Kingdom and Italian centers with no direct ENIGMA affiliation at the time of the survey were the least likely to regularly test them. Most centers tested the 16 genes through multigene panels; some centers tested TP53, PTEN, and other cancer syndrome-associated genes individually. Most centers reported (likely) pathogenic variants to patients and would test family members for such variants. Gene-specific guidelines for breast and ovarian cancer risk management were limited and differed among countries, especially with regard to starting age and type of imaging and risk-reducing surgery recommendations. Conclusion: Currently, a small number of genes beyond BRCA1/2 are routinely analyzed worldwide, and management guidelines are limited and largely based on expert opinion. To attain clinical implementation of multigene panel testing through evidence-based management practices, it is paramount that clinicians (and patients) participate in international initiatives that share panel testing data, interpret sequence variants, and collect prospective data to underpin risk estimates and evaluate the outcome of risk intervention strategies.

7.
Acta Oncol ; 57(1): 58-66, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29164972

RESUMO

BACKGROUND: Transcriptome analysis enables classification of breast tumors into molecular subtypes that correlate with prognosis and effect of therapy. We evaluated the clinical benefits of molecular subtyping compared to our current diagnostic practice. MATERIALS AND METHODS: Molecular subtyping was performed on a consecutive and unselected series of 524 tumors from women with primary breast cancer (n = 508). Tumors were classified by the 256 gene expression signature (CIT) and compared to conventional immunohistochemistry (IHC) procedures. RESULTS: More than 99% of tumors were eligible for molecular classification and final reports were available prior to the multidisciplinary conference. Using a prognostic standard mortality rate index (PSMRi) developed by the Danish Breast Cancer Group (DBCG) 39 patients were assigned with an intermediate risk and among these 16 (41%) were furthermore diagnosed by the multi-gene signature assigned with a luminal A tumor and consequently spared adjuvant chemotherapy. There was overall agreement between mRNA derived and IHC hormone receptor status, whereas IHC Ki67 protein proliferative index proved inaccurate, compared to the mRNA derived index. Forty-one patients with basal-like (basL) subtypes were screened for predisposing mutations regardless of clinical predisposition. Of those 17% carried pathogenic mutations. CONCLUSION: Transcriptome based subtyping of breast tumors evidently reduces the need for adjuvant chemotherapy and improves identification of women with predisposing mutations. The results imply that transcriptome profiling should become an integrated part of current breast cancer management.


Assuntos
Neoplasias da Mama/genética , Tomada de Decisão Clínica , Medição de Risco/métodos , Transcriptoma , Proteína BRCA2/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Carcinoma in Situ/genética , Carcinoma in Situ/patologia , Carcinoma in Situ/terapia , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/terapia , Feminino , Mutação em Linhagem Germinativa , Humanos , Imuno-Histoquímica , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptores Estrogênicos/genética , Receptores Estrogênicos/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Análise Serial de Tecidos , Ubiquitina-Proteína Ligases/genética
8.
J Mol Diagn ; 19(6): 809-816, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28822785

RESUMO

Genetic testing of BRCA1/2 includes screening for single nucleotide variants and small insertions/deletions and for larger copy number variations (CNVs), primarily by Sanger sequencing and multiplex ligation-dependent probe amplification (MLPA). With the advent of next-generation sequencing (NGS), it has become feasible to provide CNV information and sequence data using a single platform. We report the use of NGS gene panel sequencing on the Illumina MiSeq platform and JSI SeqPilot SeqNext software to call germline CNVs in BRCA1 and BRCA2. For validation 18 different BRCA1/BRCA2 CNVs previously identified by MLPA in 48 Danish breast and/or ovarian cancer families were analyzed. Moreover, 120 patient samples previously determined as negative for BRCA1/BRCA2 CNVs by MLPA were included in the analysis. Comparison of the NGS data with the data from MLPA revealed that the sensitivity was 100%, whereas the specificity was 95%. Taken together, this study validates a one-step bioinformatics work-flow to call germline BRCA1/2 CNVs using data obtained by NGS of a breast cancer gene panel. The work-flow represents a robust and easy-to-use method for full BRCA1/2 screening, which can be easily implemented in routine diagnostic testing and adapted to genes other than BRCA1/2.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Carcinoma Epitelial do Ovário , Biologia Computacional , Variações do Número de Cópias de DNA/genética , Feminino , Predisposição Genética para Doença , Testes Genéticos , Mutação em Linhagem Germinativa/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias Epiteliais e Glandulares/diagnóstico , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/patologia
9.
Clin Case Rep ; 5(6): 876-879, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28588830

RESUMO

BRCA1, c.4096+3A>G was identified in a consanguineous Danish family with several cases of breast/ovarian cancer. In silico analysis and splicing assays indicated that the variant caused aberrant splicing. However, based on segregation data and the finding of a healthy homozygous carrier, we classify the BRCA1 c.4096+3A>G variant as likely benign.

10.
J Clin Oncol ; 35(20): 2240-2250, 2017 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-28448241

RESUMO

Purpose BRCA1/2 mutations increase the risk of breast and prostate cancer in men. Common genetic variants modify cancer risks for female carriers of BRCA1/2 mutations. We investigated-for the first time to our knowledge-associations of common genetic variants with breast and prostate cancer risks for male carriers of BRCA1/ 2 mutations and implications for cancer risk prediction. Materials and Methods We genotyped 1,802 male carriers of BRCA1/2 mutations from the Consortium of Investigators of Modifiers of BRCA1/2 by using the custom Illumina OncoArray. We investigated the combined effects of established breast and prostate cancer susceptibility variants on cancer risks for male carriers of BRCA1/2 mutations by constructing weighted polygenic risk scores (PRSs) using published effect estimates as weights. Results In male carriers of BRCA1/2 mutations, PRS that was based on 88 female breast cancer susceptibility variants was associated with breast cancer risk (odds ratio per standard deviation of PRS, 1.36; 95% CI, 1.19 to 1.56; P = 8.6 × 10-6). Similarly, PRS that was based on 103 prostate cancer susceptibility variants was associated with prostate cancer risk (odds ratio per SD of PRS, 1.56; 95% CI, 1.35 to 1.81; P = 3.2 × 10-9). Large differences in absolute cancer risks were observed at the extremes of the PRS distribution. For example, prostate cancer risk by age 80 years at the 5th and 95th percentiles of the PRS varies from 7% to 26% for carriers of BRCA1 mutations and from 19% to 61% for carriers of BRCA2 mutations, respectively. Conclusion PRSs may provide informative cancer risk stratification for male carriers of BRCA1/2 mutations that might enable these men and their physicians to make informed decisions on the type and timing of breast and prostate cancer risk management.


Assuntos
Neoplasias da Mama Masculina/genética , Genes BRCA1 , Genes BRCA2 , Herança Multifatorial , Mutação , Neoplasias da Próstata/genética , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Predisposição Genética para Doença , Testes Genéticos , Estudo de Associação Genômica Ampla , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Medição de Risco/métodos
11.
JIMD Rep ; 33: 69-77, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27604842

RESUMO

Isolated complex II deficiency is a rare cause of mitochondrial disease and bi-allelic mutations in SDHB have been identified in only a few patients with complex II deficiency and a progressive neurological phenotype with onset in infancy. On the other hand, heterozygous SDHB mutations are a well-known cause of familial paraganglioma/pheochromocytoma and renal cell cancer. Here, we describe two additional patients with respiratory chain deficiency due to bi-allelic SDHB mutations. The patients' clinical, neuroradiological, and biochemical phenotype is discussed according to current knowledge on complex II and SDHB deficiency and is well in line with previously described cases, thus confirming the specific neuroradiological presentation of complex II deficiency that recently has emerged. The patients' genotype revealed one novel SDHB mutation, and one SDHB mutation, which previously has been described in heterozygous form in patients with familial paraganglioma/pheochromocytoma and/or renal cell cancer. This is only the second example in the literature where one specific SDHx mutation is associated with both recessive mitochondrial disease in one patient and familial paraganglioma/pheochromocytoma in others. Due to uncertainties regarding penetrance of different heterozygous SDHB mutations, we argue that all heterozygous SDHB mutation carriers identified in relation to SDHB-related leukoencephalopathy should be referred to relevant surveillance programs for paraganglioma/pheochromocytoma and renal cell cancer. The diagnosis of complex II deficiency due to SDHB mutations therefore raises implications for genetic counselling that go beyond the recurrence risk in the family according to an autosomal recessive inheritance.

12.
Breast Cancer Res ; 18(1): 112, 2016 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-27836010

RESUMO

BACKGROUND: Most BRCA1 or BRCA2 mutation carriers have inherited a single (heterozygous) mutation. Transheterozygotes (TH) who have inherited deleterious mutations in both BRCA1 and BRCA2 are rare, and the consequences of transheterozygosity are poorly understood. METHODS: From 32,295 female BRCA1/2 mutation carriers, we identified 93 TH (0.3 %). "Cases" were defined as TH, and "controls" were single mutations at BRCA1 (SH1) or BRCA2 (SH2). Matched SH1 "controls" carried a BRCA1 mutation found in the TH "case". Matched SH2 "controls" carried a BRCA2 mutation found in the TH "case". After matching the TH carriers with SH1 or SH2, 91 TH were matched to 9316 SH1, and 89 TH were matched to 3370 SH2. RESULTS: The majority of TH (45.2 %) involved the three common Jewish mutations. TH were more likely than SH1 and SH2 women to have been ever diagnosed with breast cancer (BC; p = 0.002). TH were more likely to be diagnosed with ovarian cancer (OC) than SH2 (p = 0.017), but not SH1. Age at BC diagnosis was the same in TH vs. SH1 (p = 0.231), but was on average 4.5 years younger in TH than in SH2 (p < 0.001). BC in TH was more likely to be estrogen receptor (ER) positive (p = 0.010) or progesterone receptor (PR) positive (p = 0.013) than in SH1, but less likely to be ER positive (p < 0.001) or PR positive (p = 0.012) than SH2. Among 15 tumors from TH patients, there was no clear pattern of loss of heterozygosity (LOH) for BRCA1 or BRCA2 in either BC or OC. CONCLUSIONS: Our observations suggest that clinical TH phenotypes resemble SH1. However, TH breast tumor marker characteristics are phenotypically intermediate to SH1 and SH2.


Assuntos
Genes BRCA1 , Genes BRCA2 , Mutação em Linhagem Germinativa , Vigilância da População , Alelos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Éxons , Feminino , Heterozigoto , Humanos , Perda de Heterozigosidade , Fenótipo , Regiões Promotoras Genéticas
13.
Cancer Genet ; 209(11): 506-514, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27886677

RESUMO

Testicular germ cell tumours of young adults are comprised of a heterogeneous group of non-seminomas and a homogeneous group of seminomas. While the majority of seminomas retain a hypo-methylated genome, a small fraction displays a highly methylated genome, resembling hyper-methylated non-seminomas. It is well established from e.g. melanoma, colorectal and thyroid cancer that a methylated phenotype can be correlated to prognosis and can be related to BRAF mutations. In the present study we investigated the global methylation level in 67 seminomas and classified them as hypo-methylated, intermediate, patchy and hyper-methylated, respectively. A selected subset representing each level of DNA methylation and the TCam2 seminoma cell line were subsequently analysed for a range of other epigenetic marks (6 histone marks and 5-hydroxymethylcytosine), the presence of the BRAF V600E de novo mutation, differences in the transcriptome and finally correlated to the clinical outcome. We did not identify any histone marks or hydroxymethylation levels that correlated with the methylation level of the genome. Some histone marks, however, showed a great variation while others were found at the same level in all the investigated seminomas. We did not identify any tumours with the BRAF V600E mutation and transcriptome analysis revealed no significant differences between hypo- and hyper-methylated seminomas. Similarly, no obvious differences in the clinical manifestation of the patients representing hypo- or hyper-methylated seminomas were identified. The level of DNA methylation in testicular seminomas consequently seems secondary to the manifestation of the tumour phenotype.


Assuntos
Metilação de DNA , Expressão Gênica , Código das Histonas , Proteínas Proto-Oncogênicas B-raf/genética , Seminoma/genética , Neoplasias Testiculares/genética , Linhagem Celular Tumoral , Epigênese Genética , Humanos , Masculino , Mutação , Fenótipo , Prognóstico , Seminoma/patologia , Neoplasias Testiculares/patologia , Adulto Jovem
14.
Artigo em Inglês | MEDLINE | ID: mdl-27279923

RESUMO

BACKGROUND: Germline mutations in the succinate dehydrogenase complex genes SDHB, SDHC, and SDHD predispose to pheochromocytomas and paragangliomas. Here, we examine the SDHB, SDHC, and SDHD mutation spectrum in the Danish population by screening of 143 Danish pheochromocytoma and paraganglioma patients. METHODS: Mutational screening was performed by Sanger sequencing or next-generation sequencing. The frequencies of variants of unknown clinical significance, e.g. intronic, missense, and synonymous variants, were determined using the Exome Aggregation Consortium database, while the significance of missense mutations was predicted by in silico and loss of heterozygosity analysis when possible. RESULTS: We report 18 germline variants; nine in SDHB, six in SDHC, and three in SDHD. Of these 18 variants, eight are novel. We classify 12 variants as likely pathogenic/pathogenic, one as likely benign, and five as variants of unknown clinical significance. CONCLUSIONS: Identifying and classifying SDHB, SDHC, and SDHD variants present in the Danish population will augment the growing knowledge on variants in these genes and may support future clinical risk assessments.

15.
Hum Mol Genet ; 25(11): 2256-2268, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27008870

RESUMO

A recent analysis using family history weighting and co-observation classification modeling indicated that BRCA1 c.594-2A > C (IVS9-2A > C), previously described to cause exon 10 skipping (a truncating alteration), displays characteristics inconsistent with those of a high risk pathogenic BRCA1 variant. We used large-scale genetic and clinical resources from the ENIGMA, CIMBA and BCAC consortia to assess pathogenicity of c.594-2A > C. The combined odds for causality considering case-control, segregation and breast tumor pathology information was 3.23 × 10-8 Our data indicate that c.594-2A > C is always in cis with c.641A > G. The spliceogenic effect of c.[594-2A > C;641A > G] was characterized using RNA analysis of human samples and splicing minigenes. As expected, c.[594-2A > C; 641A > G] caused exon 10 skipping, albeit not due to c.594-2A > C impairing the acceptor site but rather by c.641A > G modifying exon 10 splicing regulatory element(s). Multiple blood-based RNA assays indicated that the variant allele did not produce detectable levels of full-length transcripts, with a per allele BRCA1 expression profile composed of ≈70-80% truncating transcripts, and ≈20-30% of in-frame Δ9,10 transcripts predicted to encode a BRCA1 protein with tumor suppression function.We confirm that BRCA1c.[594-2A > C;641A > G] should not be considered a high-risk pathogenic variant. Importantly, results from our detailed mRNA analysis suggest that BRCA-associated cancer risk is likely not markedly increased for individuals who carry a truncating variant in BRCA1 exons 9 or 10, or any other BRCA1 allele that permits 20-30% of tumor suppressor function. More generally, our findings highlight the importance of assessing naturally occurring alternative splicing for clinical evaluation of variants in disease-causing genes.


Assuntos
Proteína BRCA1/genética , Neoplasias da Mama/genética , Mutação/genética , Neoplasias Ovarianas/genética , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Processamento Alternativo/genética , Neoplasias da Mama/patologia , Análise Mutacional de DNA , Éxons/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Sítios de Splice de RNA/genética , Processamento de RNA/genética
16.
Fam Cancer ; 15(4): 507-12, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26833046

RESUMO

Mutations in the BRCA1 and BRCA2 genes significantly contribute to hereditary breast cancer and ovarian cancer, but the phenotypic effect from different mutations is insufficiently recognized. We used a western Danish clinic-based cohort of 299 BRCA families to study the female cancer risk in mutation carriers and their untested first-degree relatives. Founder mutations were characterized and the risk of cancer was assessed in relation to the specific mutations. In BRCA1, the cumulative cancer risk at age 70 was 35 % for breast cancer and 29 % for ovarian cancer. In BRCA2, the cumulative risk was 44 % for breast cancer and 15 % for ovarian cancer. We identified 47 distinct BRCA1 mutations and 48 distinct mutations in BRCA2. Among these, 8 founder mutations [BRCA1 c.81-?_4986+?del, c.3319G>T (p.Glu1107*), c.3874delT and c.5213G>A (p.Gly1738Glu) and BRCA2 c.6373delA, c.7008-1G>A, c.7617+1G>A and c.8474delC] were found to account for 23 % of the BRCA1 mutations and for 32 % of the BRCA2 mutations. The BRCA1 mutation c.3319G>T was, compared to other BRCA1 mutations, associated with a higher risk for ovarian cancer. In conclusion, founder mutations in BRCA1 and BRCA2 contribute to up to one-third of the families in western Denmark and among these the BRCA1 c.3319G>T mutation is potentially linked to an increased risk of ovarian cancer.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Efeito Fundador , Neoplasias/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/genética , Estudos de Coortes , Dinamarca , Feminino , Predisposição Genética para Doença , Genética Populacional , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Ovarianas/genética
17.
Breast Cancer Res Treat ; 155(2): 215-22, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26740214

RESUMO

Germ-line mutations in the RAD51C gene have recently been identified in families with breast and ovarian cancer and have been associated with an increased risk of ovarian cancer. In this study, we describe the frequency of pathogenic RAD51C mutations identified in Danish breast and/or ovarian cancer families. We screened the RAD51C gene in 1228 Danish hereditary breast and/or ovarian cancer families by next-generation sequencing analysis. The frequency of the identified variants was examined in the exome sequencing project database and in data from 2000 Danish exomes and the presumed significance of missense and intronic variants was predicted by in silico analysis. We identified six families with a pathogenic mutation in RAD51C, including three frameshift mutations, one nonsense mutation, and 2 missense mutations. Overall, pathogenic RAD51C mutations were identified in 0.5 % of Danish families with increased risk of hereditary breast and/or ovarian cancer. Moreover, we identified 24 additional RAD51C variants of which 14 have not been previously reported in the literature. In this study, we determine the prevalence of RAD51C mutations in Danish breast and/or ovarian cancer families. We identified six pathogenic RAD51C mutations as well as 23 variants of uncertain clinical significance and one benign variant. Together, the study extends our knowledge of the RAD51C mutation spectrum and supports that RAD51C should be included in gene panel testing of individuals with high risk of breast and ovarian cancer.


Assuntos
Neoplasias da Mama/genética , Proteínas de Ligação a DNA/genética , Predisposição Genética para Doença/genética , Mutação/genética , Neoplasias Ovarianas/genética , Adulto , Idoso , Dinamarca , Exoma/genética , Feminino , Testes Genéticos/métodos , Humanos , Íntrons/genética , Pessoa de Meia-Idade , Risco
18.
Breast Cancer Res Treat ; 150(2): 289-98, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25724305

RESUMO

Pathogenic germline mutations in the BRCA1 gene predispose carriers to early onset breast and ovarian cancer. Clinical genetic screening of BRCA1 often reveals variants with uncertain clinical significance, complicating patient and family management. Therefore, functional examinations are urgently needed to classify whether these uncertain variants are pathogenic or benign. In this study, we investigated 14 BRCA1 variants by in silico splicing analysis and mini-gene splicing assay. All 14 alterations were missense variants located within the BRCT domain of BRCA1 and had previously been examined by functional analysis at the protein level. Results from a validated mini-gene splicing assay indicated that nine BRCA1 variants resulted in splicing aberrations leading to truncated transcripts and thus can be considered pathogenic (c.4987A>T/p.Met1663Leu, c.4988T>A/p.Met1663Lys, c.5072C>T/p.Thr1691Ile, c.5074G>C/p.Asp1692His, c.5074G>A/p.Asp1692Asn, c.5074G>T/p.Asp1692Tyr, c.5332G>A/p.Asp1778Asn, c.5332G>T/p.Asp1778Tyr, and c.5408G>C/p.Gly1803Ala), whereas five BRCA1 variants had no effect on splicing (c.4985T>C/p.Phe1662Ser, c.5072C>A/p.Thr1691Lys, c.5153G>C/p.Trp1718Ser, c.5154G>T/p.Trp1718Cys, and c.5333A>G/p.Asp1778Gly). Eight of the variants having an effect on splicing (c.4987A>T/p.Met1663Leu, c.4988T>A/p.Met1663Lys, c.5074G>C/p.Asp1692His, c.5074G>A/p.Asp1692Asn, c.5074G>T/p.Asp1692Tyr, c.5332G>A/p.Asp1778Asn, c.5332G>T/p.Asp1778Tyr, and c.5408G>C/p.Gly1803Ala) were previously determined to have no or an uncertain effect on the protein level, whereas one variant (c.5072C>T/p.Thr1691Ile) were shown to have a strong effect on the protein level as well. In conclusion, our study emphasizes that in silico splicing prediction and mini-gene splicing analysis are important for the classification of BRCA1 missense variants located close to exon/intron boundaries.


Assuntos
Proteína BRCA1/genética , Mutação de Sentido Incorreto , Processamento de RNA , Sequência de Bases , Neoplasias da Mama , Análise Mutacional de DNA , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Testes Genéticos , Mutação em Linhagem Germinativa , Humanos
19.
PLoS One ; 10(3): e0122662, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25803691

RESUMO

Both environmental and host factors influence risk of cutaneous melanoma (CM), and worldwide, the incidence varies depending on constitutional determinants of skin type and pigmentation, latitude, and patterns of sun exposure. We performed genetic analysis of CDKN2A, CDK4, BAP1, MC1R, and MITFp.E318K in Danish high-risk melanoma cases and found CDKN2A germline mutations in 11.3% of CM families with three or more affected individuals, including four previously undescribed mutations. Rare mutations were also seen in CDK4 and BAP1, while MC1R variants were common, occurring at more than twice the frequency compared to Danish controls. The MITF p.E318K variant similarly occurred at an approximately three-fold higher frequency in melanoma cases than controls. To conclude, we propose that mutation screening of CDKN2A and CDK4 in Denmark should predominantly be performed in families with at least 3 cases of CM. In addition, we recommend that testing of BAP1 should not be conducted routinely in CM families but should be reserved for families with CM and uveal melanoma, or mesothelioma.


Assuntos
Genes Neoplásicos/genética , Predisposição Genética para Doença/genética , Testes Genéticos/normas , Melanoma/epidemiologia , Melanoma/genética , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/genética , Quinase 4 Dependente de Ciclina , Inibidor p16 de Quinase Dependente de Ciclina/genética , Dinamarca/epidemiologia , Mutação em Linhagem Germinativa/genética , Humanos , Fator de Transcrição Associado à Microftalmia , Receptor Tipo 1 de Melanocortina , Proteínas Supressoras de Tumor , Ubiquitina Tiolesterase
20.
BMC Cancer ; 15: 35, 2015 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-25655188

RESUMO

BACKGROUND: Human epidermal growth factor receptor-2 (HER2) overexpression and gene amplification are currently established by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH), respectively. This study investigates whether high-density single nucleotide polymorphism (SNP) arrays can provide additional diagnostic power to assess HER2 gene status. METHODS: DNA from 65 breast tumor samples previously diagnosed by HER2 IHC and FISH analysis were blinded and examined for HER2 copy number variation employing SNP array analysis. RESULTS: SNP array analysis identified 24 (37%) samples with selective amplification or imbalance of the HER2 region in the q-arm of chromosome 17. In contrast, only 15 (23%) tumors were found to have HER2 amplification by IHC and FISH analysis. In total, there was a discrepancy in 19 (29%) samples between SNP array and IHC/FISH analysis. In 12 of these cases, the discrepancy towards FISH could be attributed to concomitant amplification or deletion of the centromeric region, which harbors the FISH reference probe sequence. In 3 tumors, repeated IHC/FISH analysis revealed that the original IHC/FISH analysis had failed to indicate the correct HER2 expression level. Finally, the SNP array analysis revealed that more than two thirds of the samples exhibited polyploidy that was unrecognized by conventional FISH. CONCLUSIONS: Collectively, the data show that determination of HER2 copy number variations by SNP array-based genomic segmentation analysis is an effective supplement to IHC/FISH HER2 analysis that, by providing additional diagnostic sensitivity and accuracy, may elect more women for targeted treatment with HER2 inhibitors.


Assuntos
Neoplasias da Mama/genética , Amplificação de Genes , Genômica , Polimorfismo de Nucleotídeo Único , Poliploidia , Receptor ErbB-2/genética , Neoplasias da Mama/diagnóstico , Variações do Número de Cópias de DNA , Feminino , Genômica/métodos , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Receptor ErbB-2/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...