BRCA1 Expression by Immunohistochemistry and Prognosis in Ovarian Cancer: A Systematic Review and Meta-Analysis

BRCA1 Promoter Methylation in Ovarian Cancer: Clinical Relevance and a Novel Diagnostic Approach Using Fragment Analysis

Homologous recombination deficiency (HRD) tests, including MyChoice CDx, are companion diagnostics for poly (ADP-ribose) polymerase (PARP) inhibitors. BRCA1 promoter hypermethylation, a major HRD cause, may correlate with poorer prognosis. This study aimed to develop a simple, accurate method for detecting BRCA1 promoter hypermethylation and elucidate the characteristics of such cases. BRCA1 promoter methylation was analyzed using bisulfite sequencing (BIS-seq) in high-grade serous ovarian carcinoma specimens. We developed a newly developed BRCA1 methylation assay, BRCA1-Fragment Analysis of Methylation (BRCA1-FAM), which combines restriction enzyme digestion with fragment analysis. The accuracy of this assay was compared to the results of BIS-seq. We evaluated the relationship between BRCA1 promoter hypermethylation and prognosis and examined its association with BRCA1 expression and loss of heterozygosity. BRCA1 mutations and promoter methylation were mutually exclusive in the analyzed cases, with methylation observed in 28.9% (22/76) of primary debulking surgery cases. The BRCA1-FAM showed high sensitivity (91.3%) and specificity (100%) for detecting BRCA1 promoter hypermethylation, comparable to BIS-seq. Cases with BRCA1 promoter hypermethylation had significantly poorer progression-free survival (log-rank test, p = 0.048). Among these cases, 86.4% displayed abnormal BRCA1 immunostaining, with lower frequencies of BRCA1 loss of heterozygosity compared to those of other groups. BRCA1 promoter hypermethylation is associated with poor prognosis, underscoring the importance of its identification for HRD stratification. BRCA1-FAM is a simple and highly accurate method for evaluating BRCA1 promoter methylation. This approach may potentially enhance the precision of personalized therapies for ovarian cancer.

Downregulated Dual-Specificity Protein Phosphatase 1 in Ovarian Carcinoma: A Comprehensive Study With Multiple Methods

Introduction: We aimed to explore the abnormal expression of dual-specificity protein phosphatase 1 (DUSP1) and its latent molecular mechanisms in ovarian carcinoma (OVCA).

Materials and Methods: Two clinical cohorts collected from two different hospitals were used to evaluate the expression of DUSP1 protein in OVCA tissues. RNA-sequencing and microarray datasets were utilised to verify DUSP1 expression at mRNA levels in both OVCA tissues and in the peripheral blood of OVCA patients. Furthermore, an integrated calculation was performed to pool the standard mean difference (SMD) from each cohort in order to comprehensively assess the expression of DUSP1 in OVCA. Furthermore, we examined the relationship among DUSP1, tumour microenvironment (TME), and chemotherapy resistance in OVCA. Moreover, we used pathway enrichment analysis to explore the underlying mechanisms of DUSP1 in OVCA.

Results: A pooled SMD of −1.19 (95% CI [−2.00, −0.38], p = 0.004) with 1,240 samples revealed that DUSP1 was downregulated in OVCA at both mRNA and protein levels. The area under the receiver operating characteristic curve of 0.9235 indicated the downregulated DUSP1 in peripheral blood may have a non-invasive diagnostic value in OVCA. Through six algorithms, we identified that DUSP1 may related to tumour-infiltrating T cells and cancer associated fibroblasts (CAFs) in OVCA. Pathway enrichment demonstrated that DUSP1 might participate in the mitogen-activated protein kinase (MAPK) signalling pathway. Furthermore, DUSP1 may have relations with chemotherapy resistance, and a favourable combining affinity was observed in the paclitaxel-DUSP1 docking model.

Conclusion: DUSP1 was downregulated in OVCA, and this decreasing trend may affect the infiltration of CAFs. Finally, DUSP1 may have a targeting relation with paclitaxel and participate in MAPK signaling pathways.

BRCA1 Promoter Methylation and Clinical Outcomes in Ovarian Cancer: An Individual Patient Data Meta-Analysis

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.

Prognostic significance of preoperative prognostic nutritional index in ovarian cancer: A systematic review and meta-analysis

BACKGROUND

The prognostic significance of preoperative prognostic nutritional index (PNI) in ovarian cancer (OC) is uncertain, and this study is aimed to clarify the prognostic significance.

METHODS

We used 4 common databases for conducting a systematic review and meta-analysis, and eligible studies were included in the analysis. The association of preoperative PNI with overall survival (OS), progression-free survival (PFS), and clinicopathological parameters was analyzed.

RESULTS

A total of 2050 patients with OC receiving the surgical treatment were analyzed in this study. Patients with low PNI tended to have a shorter OS (hazard ratio [HR] = 1.82, 95% CI = 1.30-2.55, P < .01) and PFS (HR = 1.91, 95% CI = 1.53-2.39, P < .01) compared with those with high PNI. Besides, low PNI was significantly associated with more advanced International Federation of Gynecology and Obstetrics stage (P < .01), the occurrence of ascites (P < .01), larger residual tumor (P < .01), insensitive to chemotherapy (P < .01), and higher CA125 (P < .01) compared with high PNI in OC.

CONCLUSION

Low preoperative PNI is associated with shorter OS, shorter PFS, and worse clinicopathological parameters in OC. Low preoperative PNI is an unfavorable prognostic indicator of patients with OC.