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1.
Proc Natl Acad Sci U S A ; 121(10): e2313205121, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38408235

RESUMO

Marine protected areas (MPAs) are widely used for ocean conservation, yet the relative impacts of various types of MPAs are poorly understood. We estimated impacts on fish biomass from no-take and multiple-use (fished) MPAs, employing a rigorous matched counterfactual design with a global dataset of >14,000 surveys in and around 216 MPAs. Both no-take and multiple-use MPAs generated positive conservation outcomes relative to no protection (58.2% and 12.6% fish biomass increases, respectively), with smaller estimated differences between the two MPA types when controlling for additional confounding factors (8.3% increase). Relative performance depended on context and management: no-take MPAs performed better in areas of high human pressure but similar to multiple-use in remote locations. Multiple-use MPA performance was low in high-pressure areas but improved significantly with better management, producing similar outcomes to no-take MPAs when adequately staffed and appropriate use regulations were applied. For priority conservation areas where no-take restrictions are not possible or ethical, our findings show that a portfolio of well-designed and well-managed multiple-use MPAs represents a viable and potentially equitable pathway to advance local and global conservation.


Assuntos
Conservação dos Recursos Naturais , Pesqueiros , Animais , Humanos , Biomassa , Peixes , Ecossistema
2.
Am Heart J ; 269: 72-83, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38061683

RESUMO

BACKGROUND: Despite guidelines and strong evidence supporting intravenous thrombolysis and endovascular thrombectomy for acute stroke, access to these interventions remains a challenge. The objective of the IMPROVE stroke care program was to accelerate acute stroke care delivery by implementing best practices and improving the regional systems of care within comprehensive stroke networks. METHODS: The IMPROVE Stroke Care program was a prospective quality improvement program based on established models used in acute coronary care. Nine hub hospitals (comprehensive stroke centers), 52 regional/community referral hospitals (spokes), and over 100 emergency medical service agencies participated. Through 6 regional meetings, 49 best practices were chosen for improvement by the participating sites. Over 2 years, progress was tracked and discussed weekly and performance reviews were disseminated quarterly. RESULTS: Data were collected on 21,647 stroke code activations of which 8,502 (39.3%) activations had a final diagnosis of stroke. There were 7,226 (85.0%) ischemic strokes, and thrombolytic therapy was administered 2,814 times (38.9%). There was significant overall improvement in the proportion that received lytic therapy within 45 minutes (baseline of 44.6%-60.4%). The hubs were more frequently achieving this at baseline, but both site types improved. A total of 1,455 (17.1%) thrombectomies were included in the data of which 401 (27.6%) were transferred from a spoke. There was no clinically significant change in door-to-groin times for hub-presenting thrombectomy patients, however, significant improvement occurred for transferred cases, 46 minutes (interquartile range [IQR] 36, 115.5) at baseline to 27 minutes (IQR 10, 59). CONCLUSIONS: The IMPROVE program approach was successful at improving the delivery of thrombolytic intervention across the consortium at both spoke and hub sites through collaborative efforts to operationalize guideline-based care through iterative sharing of performance and best practices for implementation. Our approach allowed identification of both opportunities for improvement and operational best practices providing guidance on how best to create a regional stroke care network and operationalize the published acute stroke care guidelines.


Assuntos
Melhoria de Qualidade , Acidente Vascular Cerebral , Humanos , Estudos Prospectivos , Acidente Vascular Cerebral/diagnóstico , Fibrinolíticos/uso terapêutico , Terapia Trombolítica , Resultado do Tratamento , Tempo para o Tratamento
3.
Am J Hum Genet ; 102(2): 233-248, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29394989

RESUMO

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.


Assuntos
Algoritmos , Substituição de Aminoácidos , Proteína BRCA2/genética , Neoplasias da Mama/genética , Mutação de Sentido Incorreto , Proteínas de Neoplasias/genética , Sequência de Aminoácidos , Teorema de Bayes , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Biologia Computacional/métodos , Bases de Dados Genéticas , Feminino , Expressão Gênica , Testes Genéticos , Humanos , Curva ROC , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
4.
Genet Med ; 23(2): 306-315, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33087888

RESUMO

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.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Proteína BRCA1/genética , Neoplasias da Mama/genética , Feminino , Aconselhamento Genético , Predisposição Genética para Doença , Testes Genéticos , Genômica , Humanos , Neoplasias Ovarianas/genética
5.
J Biol Chem ; 294(15): 5980-5992, 2019 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-30765603

RESUMO

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.


Assuntos
Proteína BRCA1 , Neoplasias da Mama , Modelos Moleculares , Mutação de Sentido Incorreto , Neoplasias Ovarianas , Substituição de Aminoácidos , Proteína BRCA1/química , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Feminino , Células HEK293 , Humanos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Domínios Proteicos , Relação Estrutura-Atividade
6.
Genome Res ; 26(3): 351-64, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26772197

RESUMO

Although deoxyribonuclease I (DNase I) was used to probe the structure of the nucleosome in the 1960s and 1970s, in the current high-throughput sequencing era, DNase I has mainly been used to study genomic regions devoid of nucleosomes. Here, we reveal for the first time that DNase I can be used to precisely map the (translational) positions of in vivo nucleosomes genome-wide. Specifically, exploiting a distinctive DNase I cleavage profile within nucleosome-associated DNA--including a signature 10.3 base pair oscillation that corresponds to accessibility of the minor groove as DNA winds around the nucleosome--we develop a Bayes-factor-based method that can be used to map nucleosome positions along the genome. Compared to methods that require genetically modified histones, our DNase-based approach is easily applied in any organism, which we demonstrate by producing maps in yeast and human. Compared to micrococcal nuclease (MNase)-based methods that map nucleosomes based on cuts in linker regions, we utilize DNase I cuts both outside and within nucleosomal DNA; the oscillatory nature of the DNase I cleavage profile within nucleosomal DNA enables us to identify translational positioning details not apparent in MNase digestion of linker DNA. Because the oscillatory pattern corresponds to nucleosome rotational positioning, it also reveals the rotational context of transcription factor (TF) binding sites. We show that potential binding sites within nucleosome-associated DNA are often centered preferentially on an exposed major or minor groove. This preferential localization may modulate TF interaction with nucleosome-associated DNA as TFs search for binding sites.


Assuntos
Mapeamento Cromossômico , DNA/genética , DNA/metabolismo , Desoxirribonuclease I/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Nucleossomos/metabolismo , Sítios de Ligação , Cromatina/genética , Cromatina/metabolismo , Biologia Computacional/métodos , Genoma Fúngico , Genoma Humano , Genômica/métodos , Humanos , Motivos de Nucleotídeos , Ligação Proteica , Fatores de Transcrição/metabolismo
7.
Genet Med ; 21(1): 71-80, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29884841

RESUMO

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.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Neoplasias Ovarianas/genética , Algoritmos , Neoplasias da Mama/patologia , Simulação por Computador , Feminino , Predisposição Genética para Doença , Humanos , Mutação de Sentido Incorreto/genética , Neoplasias Ovarianas/patologia
8.
Hum Mol Genet ; 25(16): 3600-3612, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27378695

RESUMO

Rare and low frequency variants are not well covered in most germline genotyping arrays and are understudied in relation to epithelial ovarian cancer (EOC) risk. To address this gap, we used genotyping arrays targeting rarer protein-coding variation in 8,165 EOC cases and 11,619 controls from the international Ovarian Cancer Association Consortium (OCAC). Pooled association analyses were conducted at the variant and gene level for 98,543 variants directly genotyped through two exome genotyping projects. Only common variants that represent or are in strong linkage disequilibrium (LD) with previously-identified signals at established loci reached traditional thresholds for exome-wide significance (P < 5.0 × 10 - 7). One of the most significant signals (Pall histologies = 1.01 × 10 - 13;Pserous = 3.54 × 10 - 14) occurred at 3q25.31 for rs62273959, a missense variant mapping to the LEKR1 gene that is in LD (r2 = 0.90) with a previously identified 'best hit' (rs7651446) mapping to an intron of TIPARP. Suggestive associations (5.0 × 10 - 5 > P≥5.0 ×10 - 7) were detected for rare and low-frequency variants at 16 novel loci. Four rare missense variants were identified (ACTBL2 rs73757391 (5q11.2), BTD rs200337373 (3p25.1), KRT13 rs150321809 (17q21.2) and MC2R rs104894658 (18p11.21)), but only MC2R rs104894668 had a large effect size (OR = 9.66). Genes most strongly associated with EOC risk included ACTBL2 (PAML = 3.23 × 10 - 5; PSKAT-o = 9.23 × 10 - 4) and KRT13 (PAML = 1.67 × 10 - 4; PSKAT-o = 1.07 × 10 - 5), reaffirming variant-level analysis. In summary, this large study identified several rare and low-frequency variants and genes that may contribute to EOC susceptibility, albeit with possible small effects. Future studies that integrate epidemiology, sequencing, and functional assays are needed to further unravel the unexplained heritability and biology of this disease.


Assuntos
Actinas/genética , Biotinidase/genética , Queratina-13/genética , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , Receptor Tipo 2 de Melanocortina/genética , Carcinoma Epitelial do Ovário , Exoma/genética , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Proteínas de Neoplasias/genética , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/patologia , Polimorfismo de Nucleotídeo Único
9.
Am J Epidemiol ; 184(8): 579-589, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27698005

RESUMO

Previously developed models for predicting absolute risk of invasive epithelial ovarian cancer have included a limited number of risk factors and have had low discriminatory power (area under the receiver operating characteristic curve (AUC) < 0.60). Because of this, we developed and internally validated a relative risk prediction model that incorporates 17 established epidemiologic risk factors and 17 genome-wide significant single nucleotide polymorphisms (SNPs) using data from 11 case-control studies in the United States (5,793 cases; 9,512 controls) from the Ovarian Cancer Association Consortium (data accrued from 1992 to 2010). We developed a hierarchical logistic regression model for predicting case-control status that included imputation of missing data. We randomly divided the data into an 80% training sample and used the remaining 20% for model evaluation. The AUC for the full model was 0.664. A reduced model without SNPs performed similarly (AUC = 0.649). Both models performed better than a baseline model that included age and study site only (AUC = 0.563). The best predictive power was obtained in the full model among women younger than 50 years of age (AUC = 0.714); however, the addition of SNPs increased the AUC the most for women older than 50 years of age (AUC = 0.638 vs. 0.616). Adapting this improved model to estimate absolute risk and evaluating it in prospective data sets is warranted.


Assuntos
Loci Gênicos/genética , Modelos Logísticos , Neoplasias Epiteliais e Glandulares/etiologia , Neoplasias Ovarianas/etiologia , Adulto , Idoso , Área Sob a Curva , Carcinoma Epitelial do Ovário , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , Polimorfismo de Nucleotídeo Único , Medição de Risco/métodos , Fatores de Risco , Estados Unidos
10.
Carcinogenesis ; 36(11): 1341-53, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26424751

RESUMO

Genome-wide association studies have identified 20 genomic regions associated with risk of epithelial ovarian cancer (EOC), but many additional risk variants may exist. Here, we evaluated associations between common genetic variants [single nucleotide polymorphisms (SNPs) and indels] in DNA repair genes and EOC risk. We genotyped 2896 common variants at 143 gene loci in DNA samples from 15 397 patients with invasive EOC and controls. We found evidence of associations with EOC risk for variants at FANCA, EXO1, E2F4, E2F2, CREB5 and CHEK2 genes (P ≤ 0.001). The strongest risk association was for CHEK2 SNP rs17507066 with serous EOC (P = 4.74 x 10(-7)). Additional genotyping and imputation of genotypes from the 1000 genomes project identified a slightly more significant association for CHEK2 SNP rs6005807 (r (2) with rs17507066 = 0.84, odds ratio (OR) 1.17, 95% CI 1.11-1.24, P = 1.1×10(-7)). We identified 293 variants in the region with likelihood ratios of less than 1:100 for representing the causal variant. Functional annotation identified 25 candidate SNPs that alter transcription factor binding sites within regulatory elements active in EOC precursor tissues. In The Cancer Genome Atlas dataset, CHEK2 gene expression was significantly higher in primary EOCs compared to normal fallopian tube tissues (P = 3.72×10(-8)). We also identified an association between genotypes of the candidate causal SNP rs12166475 (r (2) = 0.99 with rs6005807) and CHEK2 expression (P = 2.70×10(-8)). These data suggest that common variants at 22q12.1 are associated with risk of serous EOC and CHEK2 as a plausible target susceptibility gene.


Assuntos
Quinase do Ponto de Checagem 2/genética , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , Carcinoma Epitelial do Ovário , Estudos de Casos e Controles , Feminino , Loci Gênicos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Fatores de Risco
11.
Proc Biol Sci ; 282(1810)2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26085586

RESUMO

Hosts of brood-parasitic birds must distinguish their own eggs from parasitic mimics, or pay the cost of mistakenly raising a foreign chick. Egg discrimination is easier when different host females of the same species each lay visually distinctive eggs (egg 'signatures'), which helps to foil mimicry by parasites. Here, we ask whether brood parasitism is associated with lower levels of correlation between different egg traits in hosts, making individual host signatures more distinctive and informative. We used entropy as an index of the potential information content encoded by nine aspects of colour, pattern and luminance of eggs of different species in two African bird families (Cisticolidae parasitized by cuckoo finches Anomalospiza imberbis, and Ploceidae by diederik cuckoos Chrysococcyx caprius). Parasitized species showed consistently higher entropy in egg traits than did related, unparasitized species. Decomposing entropy into two variation components revealed that this was mainly driven by parasitized species having lower levels of correlation between different egg traits, rather than higher overall levels of variation in each individual egg trait. This suggests that irrespective of the constraints that might operate on individual egg traits, hosts can further improve their defensive 'signatures' by arranging suites of egg traits into unpredictable combinations.


Assuntos
Evolução Biológica , Aves/fisiologia , Aves/parasitologia , Óvulo/fisiologia , Animais , Comportamento de Nidação , Fenótipo , Aves Canoras/parasitologia , Aves Canoras/fisiologia
12.
BMC Genomics ; 15: 398, 2014 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-24886216

RESUMO

BACKGROUND: Genetic association studies are conducted to discover genetic loci that contribute to an inherited trait, identify the variants behind these associations and ascertain their functional role in determining the phenotype. To date, functional annotations of the genetic variants have rarely played more than an indirect role in assessing evidence for association. Here, we demonstrate how these data can be systematically integrated into an association study's analysis plan. RESULTS: We developed a Bayesian statistical model for the prior probability of phenotype-genotype association that incorporates data from past association studies and publicly available functional annotation data regarding the susceptibility variants under study. The model takes the form of a binary regression of association status on a set of annotation variables whose coefficients were estimated through an analysis of associated SNPs in the GWAS Catalog (GC). The functional predictors examined included measures that have been demonstrated to correlate with the association status of SNPs in the GC and some whose utility in this regard is speculative: summaries of the UCSC Human Genome Browser ENCODE super-track data, dbSNP function class, sequence conservation summaries, proximity to genomic variants in the Database of Genomic Variants and known regulatory elements in the Open Regulatory Annotation database, PolyPhen-2 probabilities and RegulomeDB categories. Because we expected that only a fraction of the annotations would contribute to predicting association, we employed a penalized likelihood method to reduce the impact of non-informative predictors and evaluated the model's ability to predict GC SNPs not used to construct the model. We show that the functional data alone are predictive of a SNP's presence in the GC. Further, using data from a genome-wide study of ovarian cancer, we demonstrate that their use as prior data when testing for association is practical at the genome-wide scale and improves power to detect associations. CONCLUSIONS: We show how diverse functional annotations can be efficiently combined to create 'functional signatures' that predict the a priori odds of a variant's association to a trait and how these signatures can be integrated into a standard genome-wide-scale association analysis, resulting in improved power to detect truly associated variants.


Assuntos
Estudos de Associação Genética/métodos , Loci Gênicos , Estudo de Associação Genômica Ampla/métodos , Polimorfismo de Nucleotídeo Único , Suscetibilidade a Doenças , Feminino , Humanos , Anotação de Sequência Molecular , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia
13.
Breast Cancer Res ; 16(4): 415, 2014 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-25091696

RESUMO

INTRODUCTION: Remodeling of cellular metabolism appears to be a consequence and possibly a cause of oncogenic transformation in human cancers. Specific aspects of altered tumor metabolism may be amenable to therapeutic intervention and could be coordinated with other targeted therapies. In breast cancer, the genetic landscape has been defined most comprehensively in efforts such as The Cancer Genome Atlas (TCGA). However, little is known about how alterations of tumor metabolism correlate with this landscape. METHODS: In total 25 cancers (23 fully analyzed by TCGA) and 5 normal breast specimens were analyzed by gas chromatography/mass spectrometry and liquid chromatography/mass spectrometry, quantitating 399 identifiable metabolites. RESULTS: We found strong differences correlated with hormone receptor status with 18% of the metabolites elevated in estrogen receptor negative (ER-) cancers compared to estrogen receptor positive (ER+) including many glycolytic and glycogenolytic intermediates consistent with increased Warburg effects. Glutathione (GSH) pathway components were also elevated in ER- tumors consistent with an increased requirement for handling higher levels of oxidative stress. Additionally, ER- tumors had high levels of the oncometabolite 2-hydroxyglutarate (2-HG) and the immunomodulatory tryptophan metabolite kynurenine. Kynurenine levels were correlated with the expression of tryptophan-degrading enzyme (IDO1). However, high levels of 2-HG were not associated with somatic mutations or expression levels of IDH1 or IDH2. BRCA1 mRNA levels were positively associated with coenzyme A, acetyl coenzyme A, and GSH and negatively associated with multiple lipid species, supporting the regulation of ACC1 and NRF2 by BRCA1. Different driver mutations were associated with distinct patterns of specific metabolites, such as lower levels of several lipid-glycerophosphocholines in tumors with mutated TP53. A strong metabolomic signature associated with proliferation rate was also observed; the metabolites in this signature overlap broadly with metabolites that define ER status as receptor status and proliferation rate were correlated. CONCLUSIONS: The addition of metabolomic profiles to the public domain TCGA dataset provides an important new tool for discovery and hypothesis testing of the genetic regulation of tumor metabolism. Particular sets of metabolites may reveal insights into the metabolic dysregulation that underlie the heterogeneity of breast cancer.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Genômica , Metabolômica , Proliferação de Células , Análise por Conglomerados , Feminino , Glutationa/metabolismo , Humanos , Metaboloma , Mutação , Receptores de Estrogênio/metabolismo
14.
Genome Res ; 21(1): 74-82, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21156726

RESUMO

Epithelial ovarian cancer is the leading cause of death among gynecologic malignancies. Diagnosis usually occurs after metastatic spread, largely reflecting vague symptoms of early disease combined with lack of an effective screening strategy. Epigenetic mechanisms of gene regulation, including DNA methylation, are fundamental to normal cellular function and also play a major role in carcinogenesis. To elucidate the biological and clinical relevance of DNA methylation in ovarian cancer, we conducted expression microarray analysis of 39 cell lines and 17 primary culture specimens grown in the presence or absence of DNA methyltransferase (DNMT) inhibitors. Two parameters, induction of expression and standard deviation among untreated samples, identified 378 candidate methylated genes, many relevant to TGF-beta signaling. We analyzed 43 of these genes and they all exhibited methylation. Treatment with DNMT inhibitors increased TGF-beta pathway activity. Hierarchical clustering of ovarian cancers using the 378 genes reproducibly generated a distinct gene cluster strongly correlated with TGF-beta pathway activity that discriminates patients based on age. These data suggest that accumulation of age-related epigenetic modifications leads to suppression of TGF-beta signaling and contributes to ovarian carcinogenesis.


Assuntos
Epigênese Genética , Perfilação da Expressão Gênica , Fator de Crescimento Transformador beta/metabolismo , Carcinoma Epitelial do Ovário , Linhagem Celular Tumoral , Metilação de DNA , Epigenômica , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Epiteliais e Glandulares/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Transdução de Sinais , Fator de Crescimento Transformador beta/genética , Células Tumorais Cultivadas
15.
Nature ; 453(7197): 944-7, 2008 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-18463633

RESUMO

A significant fraction of the Saccharomyces cerevisiae genome is transcribed periodically during the cell division cycle, indicating that properly timed gene expression is important for regulating cell-cycle events. Genomic analyses of the localization and expression dynamics of transcription factors suggest that a network of sequentially expressed transcription factors could control the temporal programme of transcription during the cell cycle. However, directed studies interrogating small numbers of genes indicate that their periodic transcription is governed by the activity of cyclin-dependent kinases (CDKs). To determine the extent to which the global cell-cycle transcription programme is controlled by cyclin-CDK complexes, we examined genome-wide transcription dynamics in budding yeast mutant cells that do not express S-phase and mitotic cyclins. Here we show that a significant fraction of periodic genes are aberrantly expressed in the cyclin mutant. Although cells lacking cyclins are blocked at the G1/S border, nearly 70% of periodic genes continued to be expressed periodically and on schedule. Our findings reveal that although CDKs have a function in the regulation of cell-cycle transcription, they are not solely responsible for establishing the global periodic transcription programme. We propose that periodic transcription is an emergent property of a transcription factor network that can function as a cell-cycle oscillator independently of, and in tandem with, the CDK oscillator.


Assuntos
Relógios Biológicos/fisiologia , Ciclo Celular/genética , Quinases Ciclina-Dependentes/metabolismo , Regulação Fúngica da Expressão Gênica , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Transcrição Gênica , Quinases Ciclina-Dependentes/genética , Ciclinas/genética , Ciclinas/metabolismo , Fase G1 , Mutação/genética , Periodicidade , Fase S , Fatores de Tempo
16.
JCO Clin Cancer Inform ; 8: e2300251, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38709234

RESUMO

PURPOSE: The emergence of large real-world clinical databases and tools to mine electronic medical records has allowed for an unprecedented look at large data sets with clinical and epidemiologic correlates. In clinical cancer genetics, real-world databases allow for the investigation of prevalence and effectiveness of prevention strategies and targeted treatments and for the identification of barriers to better outcomes. However, real-world data sets have inherent biases and problems (eg, selection bias, incomplete data, measurement error) that may hamper adequate analysis and affect statistical power. METHODS: Here, we leverage a real-world clinical data set from a large health network for patients with breast cancer tested for variants in BRCA1 and BRCA2 (N = 12,423). We conducted data cleaning and harmonization, cross-referenced with publicly available databases, performed variant reassessment and functional assays, and used functional data to inform a variant's clinical significance applying American College of Medical Geneticists and the Association of Molecular Pathology guidelines. RESULTS: In the cohort, White and Black patients were over-represented, whereas non-White Hispanic and Asian patients were under-represented. Incorrect or missing variant designations were the most significant contributor to data loss. While manual curation corrected many incorrect designations, a sizable fraction of patient carriers remained with incorrect or missing variant designations. Despite the large number of patients with clinical significance not reported, original reported clinical significance assessments were accurate. Reassessment of variants in which clinical significance was not reported led to a marked improvement in data quality. CONCLUSION: We identify the most common issues with BRCA1 and BRCA2 testing data entry and suggest approaches to minimize data loss and keep interpretation of clinical significance of variants up to date.


Assuntos
Proteína BRCA1 , Proteína BRCA2 , Neoplasias da Mama , Mutação em Linhagem Germinativa , Sistema de Registros , Humanos , Neoplasias da Mama/genética , Neoplasias da Mama/epidemiologia , Feminino , Proteína BRCA1/genética , Proteína BRCA2/genética , Pessoa de Meia-Idade , Predisposição Genética para Doença , Adulto , Registros Eletrônicos de Saúde , Idoso
17.
Hum Mol Genet ; 20(11): 2263-72, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21422097

RESUMO

The insulin-like growth factor (IGF) signaling axis plays an important role in cancer biology. We hypothesized that genetic variation in this pathway may influence risk of ovarian cancer. A three-center study of non-Hispanic whites including 1880 control women, 1135 women with invasive epithelial ovarian cancer and 321 women with borderline epithelial ovarian tumors was carried out to test the association between tag single-nucleotide polymorphisms (tSNPs) (n=58) in this pathway and risk of ovarian cancer. We found no association between variation in IGF1, IGFBP1 or IGFBP3 and risk of invasive disease, whereas five tSNPs in IGF2 were associated with risk of invasive epithelial ovarian cancer at P<0.05 and followed-up one of the associated SNPs. We conducted genotyping in 3216 additional non-Hispanic white cases and 5382 additional controls and were able to independently replicate our initial findings. In the combined set of studies, rs4320932 was associated with a 13% decreased risk of ovarian cancer per copy of the minor allele carried (95% confidence interval 0.81-0.93, P-trend=7.4 × 10(-5)). No heterogeneity of effect across study centers was observed (p(het)=0.25). IGF2 is emerging as an important gene for ovarian cancer; additional genotyping is warranted to further confirm these associations with IGF2 and to narrow down the region harboring the causal SNP.


Assuntos
Fator de Crescimento Insulin-Like II/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Carcinoma Epitelial do Ovário , Estudos de Casos e Controles , Feminino , Heterogeneidade Genética , Predisposição Genética para Doença , Genótipo , Humanos , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , Fatores de Risco , População Branca/genética
18.
Gynecol Oncol ; 129(1): 173-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23262379

RESUMO

OBJECTIVE: Polymorphisms in the vitamin D receptor (VDR) gene have been shown in some studies to be associated with the risk of epithelial ovarian cancer (EOC) in Caucasian women. There are no published reports among African Americans. METHODS: Case-control data from the North Carolina Ovarian Cancer Study were analyzed using logistic regression to determine the association between seven VDR polymorphisms and EOC in both Caucasians (513 cases, 532 controls) and African Americans (74 cases, 79 controls). In a larger sample of African-Americans (125 cases, 155 controls), we assessed associations between six SNPs in proximity of rs7975232. RESULTS: African American women who carried at least one minor allele of rs7975232 were at higher risk for invasive EOC controlling for age and admixture with an odds ratio (OR) for association under the log-additive model of 2.08 (95% confidence interval (CI)=1.19, 3.63, p=0.010). No association was observed between any of the VDR variants and EOC among Caucasians. A larger sample of African Americans revealed a nearly two-fold increased risk of invasive EOC associated with rs7305032, a SNP in proximity to rs7975232 (R(2)=0.369) with a log-additive OR of 1.87 (95% CI=1.20, 2.93, p=0.006). CONCLUSIONS: This is the first report showing VDR variants associated with ovarian cancer risk in African American women. A larger study of African American women is needed to confirm these findings. These results imply that vitamin D exposure is a possible modifiable risk factor of ovarian cancer among African Americans.


Assuntos
Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , Polimorfismo de Nucleotídeo Único , Receptores de Calcitriol/genética , Negro ou Afro-Americano , Carcinoma Epitelial do Ovário , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Modelos Logísticos , Neoplasias Epiteliais e Glandulares/etnologia , Neoplasias Epiteliais e Glandulares/etiologia , Neoplasias Ovarianas/etnologia , Neoplasias Ovarianas/etiologia , Fatores de Risco , População Branca
19.
Gynecol Oncol ; 129(1): 159-64, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23274563

RESUMO

INTRODUCTION: Gene expression signatures have been identified for epithelial ovarian cancer survival (TCGA) and intrinsic subtypes (Tothill et al.). One obstacle to clinical translation is that these signatures were developed using frozen tissue, whereas usually only formalin-fixed, paraffin embedded (FFPE) tissue is available. The aim of this study was to determine if gene expression signatures can be translated to fixed archival tissues. METHODS: RNA extracted from FFPE sections from 240 primary ovarian cancers was analyzed by DASL on Illumina BeadChip arrays. Concordance of expression at the individual gene level was assessed by comparing array data from the same cancers (30 frozen samples analyzed on Affymetrix arrays versus FFPE DASL). RESULTS: The correlation between FFPE and frozen survival signature estimates was 0.774. The TCGA signature using DASL was predictive of survival in 106 advanced stage high grade serous ovarian cancers (median survival 33 versus 60 months, estimated hazard ratio for death 2.30, P=0.0007). Similar to Tothill, we found using DASL that most high grade serous ovarian cancers (102/110, 93%) were assigned to subtypes 1, 2, 4 and 5, whereas most endometrioid, clear cell, mucinous and low grade serous cases (39/57, 68%) were assigned to subtypes 3 and 6 (P<10e-15). CONCLUSIONS: Although individual probe estimates of microarrays may be weakly correlated between FFPE and frozen samples, combinations of probes have robust ability to predict survival and subtype. This suggests that it may be possible to use these signatures for prognostic and predictive purposes as we seek to individualize the treatment of ovarian cancer.


Assuntos
Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias Ovarianas/genética , Feminino , Formaldeído , Humanos , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Inclusão em Parafina
20.
PLoS Genet ; 6(7): e1001016, 2010 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-20628624

RESUMO

We hypothesized that variants in genes expressed as a consequence of interactions between ovarian cancer cells and the host micro-environment could contribute to cancer susceptibility. We therefore used a two-stage approach to evaluate common single nucleotide polymorphisms (SNPs) in 173 genes involved in stromal epithelial interactions in the Ovarian Cancer Association Consortium (OCAC). In the discovery stage, cases with epithelial ovarian cancer (n=675) and controls (n=1,162) were genotyped at 1,536 SNPs using an Illumina GoldenGate assay. Based on Positive Predictive Value estimates, three SNPs-PODXL rs1013368, ITGA6 rs13027811, and MMP3 rs522616-were selected for replication using TaqMan genotyping in up to 3,059 serous invasive cases and 8,905 controls from 16 OCAC case-control studies. An additional 18 SNPs with Pper-allele<0.05 in the discovery stage were selected for replication in a subset of five OCAC studies (n=1,233 serous invasive cases; n=3,364 controls). The discovery stage associations in PODXL, ITGA6, and MMP3 were attenuated in the larger replication set (adj. Pper-allele>or=0.5). However genotypes at TERT rs7726159 were associated with ovarian cancer risk in the smaller, five-study replication study (Pper-allele=0.03). Combined analysis of the discovery and replication sets for this TERT SNP showed an increased risk of serous ovarian cancer among non-Hispanic whites [adj. ORper-allele 1.14 (1.04-1.24) p=0.003]. Our study adds to the growing evidence that, like the 8q24 locus, the telomerase reverse transcriptase locus at 5p15.33, is a general cancer susceptibility locus.


Assuntos
Células Epiteliais/patologia , Predisposição Genética para Doença/genética , Neoplasias Ovarianas/genética , Polimorfismo de Nucleotídeo Único , Células Estromais/patologia , Telomerase/genética , Estudos de Casos e Controles , Cromossomos Humanos Par 5 , Feminino , Genótipo , Humanos , População Branca/genética
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