MicroRNA Signatures in Serous Ovarian Cancer: A Comparison of Prognostic Marker Targets in African Americans and Caucasians

Ovarian cancer (OC) is the second most common gynecologic malignancy in the U.S. and the leading cause of death among cancers of the female reproductive system. Notably, mortality rates have disproportionately increased among women of African ancestry compared to those of Asian or European descent. Identifying microRNA (miRNA) signatures linked to these racial disparities may improve prognostic tools and guide personalized treatment. In this study, we first identified key prognostic markers for overall survival in serous ovarian cancer (SOC) from TCGA via the Human Protein Atlas, including ITGB1 (p=0.00033), TIMP3 (p=0.0035), and BRAF (p=0.026). Using TargetScanHuman v8.0, we predicted miRNAs targeting these genes and selected those commonly associated: miR-192, miR-30d, hsa-miR-16-5p, miR-143-3p, and miR-20a-5p. Formalin-fixed, paraffin-embedded (FFPE), and fresh SOC tissue samples from African American and Caucasian patients were collected post-surgery at Loma Linda University (2010–2023). Total RNA was extracted, followed by cDNA synthesis and qRT-PCR to assess miRNA expression. Expression data from LLU were then correlated with clinicopathologic data from TCGA (n=445). miR-192-5p emerged as the most significant, showing marginal differential expression in LLU samples (p=0.0712) and a significant correlation with survival in TCGA (p=0.021). Further pathway enrichment and gene ontology analyses using miRTargetLink2.0 and Enrichr linked miR-192, miR-16-5p, miR-143-3p, and miR-20a-5p to ITGB1; miR-143-3p/miR-145-5p to BRAF; and miR-16-5p and miR-30c/d to TIMP3. These findings suggest miRNA signatures, particularly miR-192-5p, may have clinical relevance in addressing racial disparities in OC prognosis and therapy.