98%
921
2 minutes
20
Background: BRCA1 methylation has been associated with homologous recombination deficiency, a biomarker of platinum sensitivity. Studies evaluating BRCA1-methylated tubal and ovarian cancer (OC) do not consistently support improved survival following platinum chemotherapy. We examine the characteristics of BRCA1-methylated OC in a meta-analysis of individual participant data.
Methods: Data of 2636 participants across 15 studies were analyzed. BRCA1-methylated tumors were defined according to their original study. Associations between BRCA1 methylation and clinicopathological characteristics were evaluated. The effects of methylation on overall survival (OS) and progression-free survival (PFS) were examined using mixed-effects models. All statistical tests were 2-sided.
Results: 430 (16.3%) tumors were BRCA1-methylated. BRCA1 methylation was associated with younger age and advanced-stage, high-grade serous OC. There were no survival differences between BRCA1-methylated and non-BRCA1-methylated OC (median PFS = 20.0 vs 18.5 months, hazard ratio [HR] = 1.01, 95% CI = 0.87 to 1.16; P = .98; median OS = 46.6 vs 48.0 months, HR = 1.02, 95% CI = 0.87 to 1.18; P = .96). Where BRCA1/2 mutations were evaluated (n = 1248), BRCA1 methylation displayed no survival advantage over BRCA1/2-intact (BRCA1/2 wild-type non-BRCA1-methylated) OC. Studies used different methods to define BRCA1 methylation. Where BRCA1 methylation was determined using methylation-specific polymerase chain reaction and gel electrophoresis (n = 834), it was associated with improved survival (PFS: HR = 0.80, 95% CI = 0.66 to 0.97; P = .02; OS: HR = 0.80, 95% CI = 0.63 to 1.00; P = .05) on mixed-effects modeling.
Conclusion: BRCA1-methylated OC displays similar clinicopathological features to BRCA1-mutated OC but is not associated with survival. Heterogeneity within BRCA1 methylation assays influences associations. Refining these assays may better identify cases with silenced BRCA1 function and improved patient outcomes.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7735770 | PMC |
http://dx.doi.org/10.1093/jnci/djaa070 | DOI Listing |
Biochem Pharmacol
September 2025
Department of Biosciences, JIS University, 81, Nilgunj Road, Agarpara, Kolkata, West Bengal 700109, India. Electronic address:
The malignant manifestation of breast cancer is driven by complex molecular alterations that extend beyond genetic mutations to include epigenetic dysregulation. Among these, DNA methylation is a critical and reversible epigenetic modification that significantly influences breast cancer initiation, progression, and therapeutic resistance. This process, mediated by DNA methyltransferases (DNMTs), involves the addition of methyl groups to cytosine residues within CpG dinucleotides, resulting in transcriptional repression of genes.
View Article and Find Full Text PDFJ Org Chem
September 2025
Johns Hopkins University, Department of Chemistry, 3400 N. Charles St., Baltimore, Maryland 21218, United States.
Base excision repair (BER) is a DNA repair pathway responsible for protecting the genome against modified nucleotides. DNA polymerase β (Pol β) participates in this process by removing the remnants of a damaged nucleotide and filling in the resulting gap. Pol β is overexpressed in some cancers and is synthetic lethal in cells deficient in BRCA1/2, providing additional impetus for identifying inhibitors of this enzyme.
View Article and Find Full Text PDFCell Rep Med
August 2025
Department of Gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA. Electronic address:
Despite the clinical use of anti-vascular endothelial growth factor (VEGF) antibodies (AVAs) in cancer therapy, resistance frequently develops, leading to disease progression. To address this, we identify a previously unknown role for breast cancer type 1 susceptibility protein (BRCA1)-associated RING domain 1 (BARD1) in modulating AVA sensitivity. Epigenetic modulation-via global and targeted DNA methylation-reveals BARD1 as a key regulator of angiogenesis.
View Article and Find Full Text PDFCurr Issues Mol Biol
August 2025
Department of Pathology, Fox Chase Cancer Center, Temple Health, Philadelphia, PA 19121, USA.
Homologous recombination deficiency (HRD) is a pivotal biomarker in precision oncology, driving therapeutic strategies for ovarian and breast cancers through impaired DNA double-strand break repair. This narrative review synthesizes recent advances (2021-2025) in HRD's biological basis, prevalence, detection methods, and clinical implications, focusing on high-grade serous ovarian carcinoma (HGSOC; ~50% HRD prevalence) and triple-negative breast cancer (TNBC; 50-70% prevalence). HRD arises from genetic (, , ) and epigenetic alterations (e.
View Article and Find Full Text PDFJ Mol Diagn
August 2025
Service de Biopathologie, Institut de Cancérologie de Lorraine, Université de Lorraine, Centre National de la Recherche Scientifique Unité Mixte de Recherche 7039 Centre de Recherche en Automatique de Nancy, Vandœuvre-lès-Nancy, France.
Homologous recombination deficiency (HRD) affects 50% of ovarian cancers and influences poly (ADP-ribose) polymerase inhibitor efficacy. Although one-third of HRD tumors harbor a deleterious BRCA1/2 mutation, these mutations are not the sole cause of HRD. Promoter methylation of BRCA1 and RAD51C contributes to 19% and 2% of cases, respectively.
View Article and Find Full Text PDF