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1.
Am J Hum Genet ; 111(3): 584-593, 2024 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-38417439

RESUMEN

Variants of uncertain significance (VUSs) in BRCA2 are a common result of hereditary cancer genetic testing. While more than 4,000 unique VUSs, comprised of missense or intronic variants, have been identified in BRCA2, the few missense variants now classified clinically as pathogenic or likely pathogenic are predominantly located in the region encoding the C-terminal DNA binding domain (DBD). We report on functional evaluation of the influence of 462 BRCA2 missense variants affecting the DBD on DNA repair activity of BRCA2 using a homology-directed DNA double-strand break repair assay. Of these, 137 were functionally abnormal, 313 were functionally normal, and 12 demonstrated intermediate function. Comparisons with other functional studies of BRCA2 missense variants yielded strong correlations. Sequence-based in silico prediction models had high sensitivity, but limited specificity, relative to the homology-directed repair assay. Combining the functional results with clinical and genetic data in an American College of Medical Genetics (ACMG)/Association for Molecular Pathology (AMP)-like variant classification framework from a clinical testing laboratory, after excluding known splicing variants and functionally intermediate variants, classified 431 of 442 (97.5%) missense variants (129 as pathogenic/likely pathogenic and 302 as benign/likely benign). Functionally abnormal variants classified as pathogenic by ACMG/AMP rules were associated with a slightly lower risk of breast cancer (odds ratio [OR] 5.15, 95% confidence interval [CI] 3.43-7.83) than BRCA2 DBD protein truncating variants (OR 8.56, 95% CI 6.03-12.36). Overall, functional studies of BRCA2 variants using validated assays substantially improved the variant classification yield from ACMG/AMP models and are expected to improve clinical management of many individuals found to harbor germline BRCA2 missense VUS.


Asunto(s)
Neoplasias de la Mama , Predisposición Genética a la Enfermedad , Humanos , Femenino , Proteína BRCA2/genética , Pruebas Genéticas , Mutación Missense/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Células Germinativas/patología , ADN
2.
Am J Hum Genet ; 108(3): 458-468, 2021 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-33609447

RESUMEN

Determination of the clinical relevance of rare germline variants of uncertain significance (VUSs) in the BRCA2 cancer predisposition gene remains a challenge as a result of limited availability of data for use in classification models. However, laboratory-based functional data derived from validated functional assays of known sensitivity and specificity may influence the interpretation of VUSs. We evaluated 252 missense VUSs from the BRCA2 DNA-binding domain by using a homology-directed DNA repair (HDR) assay and identified 90 as non-functional and 162 as functional. The functional assay results were integrated with other available data sources into an ACMG/AMP rules-based classification framework used by a hereditary cancer testing laboratory. Of the 186 missense variants observed by the testing laboratory, 154 were classified as VUSs without functional data. However, after applying protein functional data, 86% (132/154) of the VUSs were reclassified as either likely pathogenic/pathogenic (39/132) or likely benign/benign (93/132), which impacted testing results for 1,900 individuals. These results indicate that validated functional assay data can have a substantial impact on VUS classification and associated clinical management for many individuals with inherited alterations in BRCA2.


Asunto(s)
Proteína BRCA2/genética , Neoplasias de la Mama/genética , Predisposición Genética a la Enfermedad , Reparación del ADN por Recombinación/genética , Neoplasias de la Mama/patología , Femenino , Variación Genética/genética , Humanos , Mutación Missense/genética , Relación Estructura-Actividad
3.
J Biol Chem ; 298(11): 102550, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36183837

RESUMEN

BRCA1/2-deficient ovarian carcinoma (OC) has been shown to be particularly sensitive to poly (ADP-ribose) polymerase inhibitors (PARPis). Furthermore, BRCA1/2 mutation status is currently used as a predictive biomarker for PARPi therapy. Despite providing a major clinical benefit to the majority of patients, a significant proportion of BRCA1/2-deficient OC tumors do not respond to PARPis for reasons that are incompletely understood. Using an integrated chemical, phospho- and ADP-ribosylation proteomics approach, we sought here to develop additional mechanism-based biomarker candidates for PARPi therapy in OC and identify new targets for combination therapy to overcome primary resistance. Using chemical proteomics with PARPi baits in a BRCA1-isogenic OC cell line pair, as well as patient-derived BRCA1-proficient and BRCA1-deficient tumor samples, and subsequent validation by coimmunoprecipitation, we showed differential PARP1 and PARP2 protein complex composition in PARPi-sensitive, BRCA1-deficient UWB1.289 (UWB) cells compared to PARPi-insensitive, BRCA1-reconstituted UWB1.289+BRCA1 (UWB+B) cells. In addition, global phosphoproteomics and ADP-ribosylation proteomics furthermore revealed that the PARPi rucaparib induced the cell cycle pathway and nonhomologous end joining (NHEJ) pathway in UWB cells but downregulated ErbB signaling in UWB+B cells. In addition, we observed AKT PARylation and prosurvival AKT-mTOR signaling in UWB+B cells after PARPi treatment. Consistently, we found the synergy of PARPis with DNAPK or AKT inhibitors was more pronounced in UWB+B cells, highlighting these pathways as actionable vulnerabilities. In conclusion, we demonstrate the combination of chemical proteomics, phosphoproteomics, and ADP-ribosylation proteomics can identify differential PARP1/2 complexes and diverse, but actionable, drug compensatory signaling in OC.


Asunto(s)
Neoplasias Ováricas , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Humanos , Femenino , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Proteómica , Proteínas Proto-Oncogénicas c-akt , Resistencia a Antineoplásicos , Línea Celular Tumoral , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología
4.
Hum Mutat ; 43(10): 1396-1407, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35762214

RESUMEN

Chordoma is a rare bone tumor with genetic risk factors largely unknown. We conducted a whole-exome sequencing (WES) analysis of germline DNA from 19 familial chordoma cases in five pedigrees and 137 sporadic chordoma patients and identified 17 rare germline variants in PALB2 and BRCA2, whose products play essential roles in homologous recombination (HR) and tumor suppression. One PALB2 variant showed disease cosegregation in a family with four affected people or obligate gene carrier. Chordoma cases had a significantly increased burden of rare variants in both genes when compared to population-based controls. Four of the six PALB2 variants identified from chordoma patients modestly affected HR function and three of the 11 BRCA2 variants caused loss of function in experimental assays. These results, together with previous reports of abnormal morphology and Brachyury expression of the notochord in Palb2 knockout mouse embryos and genomic signatures associated with HR defect and HR gene mutations in advanced chordomas, suggest that germline mutations in PALB2 and BRCA2 may increase chordoma susceptibility. Our data shed light on the etiology of chordoma and support the previous finding that PARP-1 inhibitors may be a potential therapy for some chordoma patients.


Asunto(s)
Proteína BRCA2 , Neoplasias de la Mama , Cordoma , Proteína del Grupo de Complementación N de la Anemia de Fanconi , Animales , Proteína BRCA2/genética , Neoplasias de la Mama/genética , Cordoma/genética , Proteína del Grupo de Complementación N de la Anemia de Fanconi/genética , Femenino , Genes BRCA2 , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Humanos , Ratones
5.
Am J Hum Genet ; 102(2): 233-248, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29394989

RESUMEN

Many variants of uncertain significance (VUS) have been identified in BRCA2 through clinical genetic testing. VUS pose a significant clinical challenge because the contribution of these variants to cancer risk has not been determined. We conducted a comprehensive assessment of VUS in the BRCA2 C-terminal DNA binding domain (DBD) by using a validated functional assay of BRCA2 homologous recombination (HR) DNA-repair activity and defined a classifier of variant pathogenicity. Among 139 variants evaluated, 54 had ?99% probability of pathogenicity, and 73 had ?95% probability of neutrality. Functional assay results were compared with predictions of variant pathogenicity from the Align-GVGD protein-sequence-based prediction algorithm, which has been used for variant classification. Relative to the HR assay, Align-GVGD significantly (p < 0.05) over-predicted pathogenic variants. We subsequently combined functional and Align-GVGD prediction results in a Bayesian hierarchical model (VarCall) to estimate the overall probability of pathogenicity for each VUS. In addition, to predict the effects of all other BRCA2 DBD variants and to prioritize variants for functional studies, we used the endoPhenotype-Optimized Sequence Ensemble (ePOSE) algorithm to train classifiers for BRCA2 variants by using data from the HR functional assay. Together, the results show that systematic functional assays in combination with in silico predictors of pathogenicity provide robust tools for clinical annotation of BRCA2 VUS.


Asunto(s)
Algoritmos , Sustitución de Aminoácidos , Proteína BRCA2/genética , Neoplasias de la Mama/genética , Mutación Missense , Proteínas de Neoplasias/genética , Secuencia de Aminoácidos , Teorema de Bayes , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/patología , Biología Computacional/métodos , Bases de Datos Genéticas , Femenino , Expresión Génica , Pruebas Genéticas , Humanos , Curva ROC , Alineación de Secuencia , Homología de Secuencia de Aminoácido
6.
Genet Med ; 23(2): 306-315, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33087888

RESUMEN

PURPOSE: BRCA1 pathogenic variant heterozygotes are at a substantially increased risk for breast and ovarian cancer. The widespread uptake of testing has led to a significant increase in the detection of missense variants in BRCA1, the vast majority of which are variants of uncertain clinical significance (VUS), posing a challenge to genetic counseling. Here, we harness a wealth of functional data for thousands of variants to aid in variant classification. METHODS: We have collected, curated, and harmonized functional data for 2701 missense variants representing 24.5% of possible missense variants in BRCA1. Results were harmonized across studies by converting data into binary categorical variables (functional impact versus no functional impact). Using a panel of reference variants we identified a subset of assays with high sensitivity and specificity (≥80%) and apply the American College of Medical Genetics and Genomics/Association for Molecular Pathology (ACMG/AMP) variant interpretation guidelines to assign evidence criteria for classification. RESULTS: Integration of data from validated assays provided ACMG/AMP evidence criteria in favor of pathogenicity for 297 variants or against pathogenicity for 2058 representing 96.2% of current VUS functionally assessed. We also explore discordant results and identify limitations in the approach. CONCLUSION: High quality functional data are available for BRCA1 missense variants and provide evidence for classification of 2355 VUS according to their pathogenicity.


Asunto(s)
Neoplasias de la Mama , Neoplasias Ováricas , Proteína BRCA1/genética , Neoplasias de la Mama/genética , Femenino , Asesoramiento Genético , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Genómica , Humanos , Neoplasias Ováricas/genética
7.
Nucleic Acids Res ; 47(20): 10662-10677, 2019 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-31586400

RESUMEN

While biallelic mutations in the PALB2 tumor suppressor cause Fanconi anemia subtype FA-N, monoallelic mutations predispose to breast and familial pancreatic cancer. Although hundreds of missense variants in PALB2 have been identified in patients to date, only a few have clear functional and clinical relevance. Herein, we investigate the effects of 44 PALB2 variants of uncertain significance found in breast cancer patients and provide detailed analysis by systematic functional assays. Our comprehensive functional analysis reveals two hotspots for potentially deleterious variations within PALB2, one at each terminus. PALB2 N-terminus variants p.P8L [c.23C>T], p.Y28C [c.83A>G], and p.R37H [c.110G>A] compromised PALB2-mediated homologous recombination. At the C-terminus, PALB2 variants p.L947F [c.2841G>T], p.L947S [c.2840T>C], and most strikingly p.T1030I [c.3089C>T] and p.W1140G [c.3418T>C], stood out with pronounced PARP inhibitor sensitivity and cytoplasmic accumulation in addition to marked defects in recruitment to DNA damage sites, interaction with BRCA2 and homologous recombination. Altogether, our findings show that a combination of functional assays is necessary to assess the impact of germline missense variants on PALB2 function, in order to guide proper classification of their deleteriousness.


Asunto(s)
Neoplasias de la Mama/genética , Proteína del Grupo de Complementación N de la Anemia de Fanconi/genética , Mutación Missense/genética , Línea Celular Tumoral , Simulación por Computador , Daño del ADN , Femenino , Sitios Genéticos , Recombinación Homóloga/genética , Humanos , Cinética , Recombinasa Rad51/metabolismo , Reproducibilidad de los Resultados
8.
J Biol Chem ; 294(15): 5980-5992, 2019 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-30765603

RESUMEN

Genetic testing for BRCA1, a DNA repair protein, can identify carriers of pathogenic variants associated with a substantially increased risk for breast and ovarian cancers. However, an association with increased risk is unclear for a large fraction of BRCA1 variants present in the human population. Most of these variants of uncertain clinical significance lead to amino acid changes in the BRCA1 protein. Functional assays are valuable tools to assess the potential pathogenicity of these variants. Here, we systematically probed the effects of substitutions in the C terminus of BRCA1: the N- and C-terminal borders of its tandem BRCT domain, the BRCT-[N-C] linker region, and the α1 and α'1 helices in BRCT-[N] and -[C]. Using a validated transcriptional assay based on a fusion of the GAL4 DNA-binding domain to the BRCA1 C terminus (amino acids 1396-1863), we assessed the functional impact of 99 missense variants of BRCA1. We include the data obtained for these 99 missense variants in a joint analysis to generate the likelihood of pathogenicity for 347 missense variants in BRCA1 using VarCall, a Bayesian integrative statistical model. The results from this analysis increase our understanding of BRCA1 regions less tolerant to changes, identify functional borders of structural domains, and predict the likelihood of pathogenicity for 98% of all BRCA1 missense variants in this region recorded in the population. This knowledge will be critical for improving risk assessment and clinical treatment of carriers of BRCA1 variants.


Asunto(s)
Proteína BRCA1 , Neoplasias de la Mama , Modelos Moleculares , Mutación Missense , Neoplasias Ováricas , Sustitución de Aminoácidos , Proteína BRCA1/química , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Femenino , Células HEK293 , Humanos , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Dominios Proteicos , Relación Estructura-Actividad
9.
Bioinformatics ; 35(21): 4462-4464, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31099399

RESUMEN

SUMMARY: Complementary advances in genomic technology and public data resources have created opportunities for researchers to conduct multifaceted examination of the genome on a large scale. To meet the need for integrative genome wide exploration, we present epiTAD. This web-based tool enables researchers to compare genomic 3D organization and annotations across multiple databases in an interactive manner to facilitate in silico discovery. AVAILABILITY AND IMPLEMENTATION: epiTAD can be accessed at https://apps.gerkelab.com/epiTAD/ where we have additionally made publicly available the source code and a Docker containerized version of the application.


Asunto(s)
Cromosomas , Programas Informáticos , Genoma , Genómica , Epidemiología Molecular
10.
Genet Med ; 22(3): 622-632, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31636395

RESUMEN

PURPOSE: Inherited pathogenic variants in PALB2 are associated with increased risk of breast and pancreatic cancer. However, the functional and clinical relevance of many missense variants of uncertain significance (VUS) identified through clinical genetic testing is unclear. The ability of patient-derived germline missense VUS to disrupt PALB2 function was assessed to identify variants with potential clinical relevance. METHODS: The influence of 84 VUS on PALB2 function was evaluated using a cellular homology directed DNA repair (HDR) assay and VUS impacting activity were further characterized using secondary functional assays. RESULTS: Four (~5%) variants (p.L24S,c.71T>C; p.L35P,c.104T>C; pI944N,c.2831T>A; and p.L1070P,c.3209T>C) disrupted PALB2-mediated HDR activity. These variants conferred sensitivity to cisplatin and a poly(ADP-ribose) polymerase (PARP) inhibitor and reduced RAD51 foci formation in response to DNA damage. The p.L24S and p.L35P variants disrupted BRCA1-PALB2 protein complexes, p.I944N was associated with protein instability, and both p.I944N and p.L1070P mislocalized PALB2 to the cytoplasm. CONCLUSION: These findings show that the HDR assay is an effective method for screening the influence of inherited variants on PALB2 function, that four missense variants impact PALB2 function and may influence cancer risk and response to therapy, and suggest that few inherited PALB2 missense variants disrupt PALB2 function in DNA repair.


Asunto(s)
Proteína BRCA1/genética , Neoplasias de la Mama/genética , Proteína del Grupo de Complementación N de la Anemia de Fanconi/genética , Recombinasa Rad51/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Daño del ADN/genética , Reparación del ADN/efectos de los fármacos , Femenino , Factor de Transcripción GATA3/genética , Predisposición Genética a la Enfermedad , Humanos , Mutación Missense/genética , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Reparación del ADN por Recombinación/genética
11.
J Med Genet ; 56(6): 347-357, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30962250

RESUMEN

The vocabulary currently used to describe genetic variants and their consequences reflects many years of studying and discovering monogenic disease with high penetrance. With the recent rapid expansion of genetic testing brought about by wide availability of high-throughput massively parallel sequencing platforms, accurate variant interpretation has become a major issue. The vocabulary used to describe single genetic variants in silico, in vitro, in vivo and as a contributor to human disease uses terms in common, but the meaning is not necessarily shared across all these contexts. In the setting of cancer genetic tests, the added dimension of using data from genetic sequencing of tumour DNA to direct treatment is an additional source of confusion to those who are not experienced in cancer genetics. The language used to describe variants identified in cancer susceptibility genetic testing typically still reflects an outdated paradigm of Mendelian inheritance with dichotomous outcomes. Cancer is a common disease with complex genetic architecture; an improved lexicon is required to better communicate among scientists, clinicians and patients, the risks and implications of genetic variants detected. This review arises from a recognition of, and discussion about, inconsistencies in vocabulary usage by members of the ENIGMA international multidisciplinary consortium focused on variant classification in breast-ovarian cancer susceptibility genes. It sets out the vocabulary commonly used in genetic variant interpretation and reporting, and suggests a framework for a common vocabulary that may facilitate understanding and clarity in clinical reporting of germline genetic tests for cancer susceptibility.


Asunto(s)
Predisposición Genética a la Enfermedad , Variación Genética , Clasificación Internacional de Enfermedades , Neoplasias de Células Germinales y Embrionarias/diagnóstico , Neoplasias de Células Germinales y Embrionarias/genética , Biomarcadores de Tumor , Biología Computacional/métodos , Perfilación de la Expresión Génica , Genes BRCA1 , Genes BRCA2 , Mutación de Línea Germinal , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Clasificación Internacional de Enfermedades/normas , Terminología como Asunto , Vocabulario Controlado
12.
Genet Med ; 21(1): 71-80, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29884841

RESUMEN

PURPOSE: To improve methods for predicting the impact of missense variants of uncertain significance (VUS) in BRCA1 and BRCA2 on protein function. METHODS: Functional data for 248 BRCA1 and 207 BRCA2 variants from assays with established high sensitivity and specificity for damaging variants were used to recalibrate 40 in silico algorithms predicting the impact of variants on protein activity. Additional random forest (RF) and naïve voting method (NVM) metapredictors for both BRCA1 and BRCA2 were developed to increase predictive accuracy. RESULTS: Optimized thresholds for in silico prediction models significantly improved the accuracy of predicted functional effects for BRCA1 and BRCA2 variants. In addition, new BRCA1-RF and BRCA2-RF metapredictors showed area under the curve (AUC) values of 0.92 (95% confidence interval [CI]: 0.88-0.96) and 0.90 (95% CI: 0.84-0.95), respectively. Similarly, the BRCA1-NVM and BRCA2-NVM models had AUCs of 0.93 and 0.90. The RF and NVM models were used to predict the pathogenicity of all possible missense variants in BRCA1 and BRCA2. CONCLUSION: The recalibrated algorithms and new metapredictors significantly improved upon current models for predicting the impact of variants in cancer risk-associated domains of BRCA1 and BRCA2. Prediction of the functional impact of all possible variants in BRCA1 and BRCA2 provides important information about the clinical relevance of variants in these genes.


Asunto(s)
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/genética , Neoplasias Ováricas/genética , Algoritmos , Neoplasias de la Mama/patología , Simulación por Computador , Femenino , Predisposición Genética a la Enfermedad , Humanos , Mutación Missense/genética , Neoplasias Ováricas/patología
13.
Hum Mol Genet ; 25(24): 5287-5299, 2016 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-27742776

RESUMEN

BRCA1-deficient cells show defects in DNA repair and rely on other members of the DNA repair machinery, which makes them sensitive to PARP inhibitors (PARPi). Although carrying a germline pathogenic variant in BRCA1/2 is the best determinant of response to PARPi, a significant percentage of the patients do not show sensitivity and/or display increased toxicity to the agent. Considering previously suggested mutation-specific BRCA1 haploinsufficiency, we aimed to investigate whether there are any differences in cellular response to PARPi olaparib depending on the BRCA1 mutation type. Lymphoblastoid cell lines derived from carriers of missense pathogenic variants in the BRCA1 BRCT domain (c.5117G > A, p.Gly1706Glu and c.5123C > A, p.Ala1708Glu) showed higher sensitivity to olaparib than cells with truncating variants or wild types (WT). Response to olaparib depended on a basal PARP enzymatic activity, but did not correlate with PARP1 expression. Interestingly, cellular sensitivity to the agent was associated with the level of BRCA1 recruitment into γH2AX foci, being the lowest in cells with missense variants. Since these variants lead to partially stable protein mutants, we propose a model in which the mutant protein acts in a dominant negative manner on the WT BRCA1, impairing the recruitment of BRCA1 into DNA damage sites and, consequently, increasing cellular sensitivity to PARPi. Taken together, our results indicate that carriers of different BRCA1 mutations could benefit from olaparib in a distinct way and show different toxicities to the agent, which could be especially relevant for a potential future use of PARPi as prophylactic agents in BRCA1 mutation carriers.


Asunto(s)
Proteína BRCA1/genética , Neoplasias Ováricas/tratamiento farmacológico , Ftalazinas/administración & dosificación , Piperazinas/administración & dosificación , Poli(ADP-Ribosa) Polimerasas/genética , Línea Celular Tumoral , Daño del ADN/efectos de los fármacos , Daño del ADN/genética , Reparación del ADN/efectos de los fármacos , Reparación del ADN/genética , Resistencia a Antineoplásicos/genética , Femenino , Mutación de Línea Germinal/genética , Humanos , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/administración & dosificación
14.
Hum Mol Genet ; 24(13): 3595-607, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25804953

RESUMEN

Understanding the regulatory landscape of the human genome is a central question in complex trait genetics. Most single-nucleotide polymorphisms (SNPs) associated with cancer risk lie in non-protein-coding regions, implicating regulatory DNA elements as functional targets of susceptibility variants. Here, we describe genome-wide annotation of regions of open chromatin and histone modification in fallopian tube and ovarian surface epithelial cells (FTSECs, OSECs), the debated cellular origins of high-grade serous ovarian cancers (HGSOCs) and in endometriosis epithelial cells (EECs), the likely precursor of clear cell ovarian carcinomas (CCOCs). The regulatory architecture of these cell types was compared with normal human mammary epithelial cells and LNCaP prostate cancer cells. We observed similar positional patterns of global enhancer signatures across the three different ovarian cancer precursor cell types, and evidence of tissue-specific regulatory signatures compared to non-gynecological cell types. We found significant enrichment for risk-associated SNPs intersecting regulatory biofeatures at 17 known HGSOC susceptibility loci in FTSECs (P = 3.8 × 10(-30)), OSECs (P = 2.4 × 10(-23)) and HMECs (P = 6.7 × 10(-15)) but not for EECs (P = 0.45) or LNCaP cells (P = 0.88). Hierarchical clustering of risk SNPs conditioned on the six different cell types indicates FTSECs and OSECs are highly related (96% of samples using multi-scale bootstrapping) suggesting both cell types may be precursors of HGSOC. These data represent the first description of regulatory catalogues of normal precursor cells for different ovarian cancer subtypes, and provide unique insights into the tissue specific regulatory variation with respect to the likely functional targets of germline genetic susceptibility variants for ovarian cancer.


Asunto(s)
Predisposición Genética a la Enfermedad , Neoplasias Ováricas/genética , Cromatina/genética , Cromatina/metabolismo , Femenino , Estudio de Asociación del Genoma Completo , Histonas/genética , Histonas/metabolismo , Humanos , Especificidad de Órganos , Neoplasias Ováricas/metabolismo , Polimorfismo de Nucleótido Simple , Secuencias Reguladoras de Ácidos Nucleicos
15.
Hum Mol Genet ; 24(18): 5356-66, 2015 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-26138067

RESUMEN

Epidemiological studies have reported inconsistent associations between telomere length (TL) and risk for various cancers. These inconsistencies are likely attributable, in part, to biases that arise due to post-diagnostic and post-treatment TL measurement. To avoid such biases, we used a Mendelian randomization approach and estimated associations between nine TL-associated SNPs and risk for five common cancer types (breast, lung, colorectal, ovarian and prostate cancer, including subtypes) using data on 51 725 cases and 62 035 controls. We then used an inverse-variance weighted average of the SNP-specific associations to estimate the association between a genetic score representing long TL and cancer risk. The long TL genetic score was significantly associated with increased risk of lung adenocarcinoma (P = 6.3 × 10(-15)), even after exclusion of a SNP residing in a known lung cancer susceptibility region (TERT-CLPTM1L) P = 6.6 × 10(-6)). Under Mendelian randomization assumptions, the association estimate [odds ratio (OR) = 2.78] is interpreted as the OR for lung adenocarcinoma corresponding to a 1000 bp increase in TL. The weighted TL SNP score was not associated with other cancer types or subtypes. Our finding that genetic determinants of long TL increase lung adenocarcinoma risk avoids issues with reverse causality and residual confounding that arise in observational studies of TL and disease risk. Under Mendelian randomization assumptions, our finding suggests that longer TL increases lung adenocarcinoma risk. However, caution regarding this causal interpretation is warranted in light of the potential issue of pleiotropy, and a more general interpretation is that SNPs influencing telomere biology are also implicated in lung adenocarcinoma risk.


Asunto(s)
Predisposición Genética a la Enfermedad , Análisis de la Aleatorización Mendeliana , Neoplasias/epidemiología , Neoplasias/genética , Homeostasis del Telómero/genética , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Estudios de Asociación Genética , Variación Genética , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Polimorfismo de Nucleótido Simple , Riesgo
16.
Int J Mol Sci ; 18(9)2017 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-28858227

RESUMEN

The deoxyribonucleic acid (DNA) damage response (DDR) is a major feature in the maintenance of genome integrity and in the suppression of tumorigenesis. PALB2 (Partner and Localizer of Breast Cancer 2 (BRCA2)) plays an important role in maintaining genome integrity through its role in the Fanconi anemia (FA) and homologous recombination (HR) DNA repair pathways. Since its identification as a BRCA2 interacting partner, PALB2 has emerged as a pivotal tumor suppressor protein associated to hereditary cancer susceptibility to breast and pancreatic cancers. In this review, we discuss how other DDR proteins (such as the kinases Ataxia Telangiectasia Mutated (ATM) and ATM- and Rad3-Related (ATR), mediators BRCA1 (Breast Cancer 1)/BRCA2 and effectors RAD51/DNA Polymerase η (Polη) interact with PALB2 to orchestrate DNA repair. We also examine the involvement of PALB2 mutations in the predisposition to cancer and the role of PALB2 in stimulating error-free DNA repair through the FA/HR pathway.


Asunto(s)
Daño del ADN , Proteína del Grupo de Complementación N de la Anemia de Fanconi , Predisposición Genética a la Enfermedad , Inestabilidad Genómica , Neoplasias , Reparación del ADN por Recombinación , Animales , Proteína del Grupo de Complementación N de la Anemia de Fanconi/genética , Proteína del Grupo de Complementación N de la Anemia de Fanconi/metabolismo , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología
18.
J Med Genet ; 52(4): 224-30, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25643705

RESUMEN

BACKGROUND: Inactivating germline mutations in the tumour suppressor gene BRCA1 are associated with a significantly increased risk of developing breast and ovarian cancer. A large number (>1500) of unique BRCA1 variants have been identified in the population and can be classified as pathogenic, non-pathogenic or as variants of unknown significance (VUS). Many VUS are rare missense variants leading to single amino acid changes. Their impact on protein function cannot be directly inferred from sequence information, precluding assessment of their pathogenicity. Thus, functional assays are critical to assess the impact of these VUS on protein activity. BRCA1 is a multifunctional protein and different assays have been used to assess the impact of variants on different biochemical activities and biological processes. METHODS AND RESULTS: To facilitate VUS analysis, we have developed a visualisation resource that compiles and displays functional data on all documented BRCA1 missense variants. BRCA1 Circos is a web-based visualisation tool based on the freely available Circos software package. The BRCA1 Circos web tool (http://research.nhgri.nih.gov/bic/circos/) aggregates data from all published BRCA1 missense variants for functional studies, harmonises their results and presents various functionalities to search and interpret individual-level functional information for each BRCA1 missense variant. CONCLUSIONS: This research visualisation tool will serve as a quick one-stop publically available reference for all the BRCA1 missense variants that have been functionally assessed. It will facilitate meta-analysis of functional data and improve assessment of pathogenicity of VUS.


Asunto(s)
Proteína BRCA1/genética , Biología Computacional/métodos , Gráficos por Computador , Internet , Mutación Missense , Programas Informáticos , Neoplasias de la Mama/genética , Análisis Mutacional de ADN , Sistemas de Administración de Bases de Datos , Bases de Datos Genéticas , Conjuntos de Datos como Asunto , Femenino , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Humanos , Neoplasias Ováricas/genética
19.
Cancer ; 121(23): 4173-80, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26287763

RESUMEN

BACKGROUND: Black women are disproportionately affected with triple-negative breast cancer and have relatively poor survival. To the authors' knowledge, it is not known to what extent differences in the clinical presentation of breast cancer between non-Hispanic white women and black women can be accounted for by the presence of mutations in the BRCA1 and BRCA2 genes. The authors sought to evaluate the frequency of BRCA pathogenic variants in a population-based sample of young black women with breast cancer. METHODS: Black women diagnosed with invasive breast cancer at age ≤50 years from 2009 to 2012 were recruited to the study through the Florida Cancer Registry. Participants underwent genetic counseling, completed a study questionnaire, and consented to release of their medical records. Saliva specimens were collected for BRCA sequencing and large rearrangement testing through multiplex ligation-dependent probe amplification. RESULTS: A DNA sample was evaluated for 396 women, 49 of whom (12.4%) had a mutation in BRCA1 or BRCA2. Eight recurrent mutations accounted for 49% of all pathogenic variants. CONCLUSIONS: To the authors' knowledge, the prevalence of BRCA mutations among the Florida-based sample of young black women with breast cancer in the current study exceeds that previously reported for non-Hispanic white women. It is appropriate to recommend BRCA testing in all young black women with invasive breast cancer.


Asunto(s)
Proteína BRCA1/genética , Proteína BRCA2/genética , Negro o Afroamericano/genética , Neoplasias de la Mama/genética , Mutación , Adulto , Neoplasias de la Mama/etnología , Neoplasias de la Mama/patología , Detección Precoz del Cáncer , Femenino , Florida , Asesoramiento Genético , Humanos , Persona de Mediana Edad , Invasividad Neoplásica , Sistema de Registros , Análisis de Secuencia de ADN/métodos , Adulto Joven
20.
Hum Genet ; 134(5): 467-78, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25324189

RESUMEN

Recent technological advances have transformed cancer genetics research. These advances have served as the basis for the generation of a number of richly annotated datasets relevant to the cancer geneticist. In addition, many of these technologies are now within reach of smaller laboratories to answer specific biological questions. Thus, one of the most pressing issues facing an experimental cancer biology research program in genetics is incorporating data from multiple sources to annotate, visualize, and analyze the system under study. Fortunately, there are several computational resources to aid in this process. However, a significant effort is required to adapt a molecular biology-based research program to take advantage of these datasets. Here, we discuss the lessons learned in our laboratory and share several recommendations to make this transition effective. This article is not meant to be a comprehensive evaluation of all the available resources, but rather highlight those that we have incorporated into our laboratory and how to choose the most appropriate ones for your research program.


Asunto(s)
Biología Computacional/tendencias , Interpretación Estadística de Datos , Genética Médica/tendencias , Neoplasias/genética , Programas Informáticos , Biología de Sistemas/tendencias , Biología Computacional/métodos , Gráficos por Computador , Bases de Datos Genéticas , Genética Médica/métodos , Humanos , Internet , Mapeo de Interacción de Proteínas , Biología de Sistemas/métodos
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