Serum miR-181a-5p, miR-214-3p, and miR-223-3p in epithelial ovarian cancer

Early detection of epithelial ovarian cancer (EOC) remains challenging due to nonspecific symptoms and limitations of current biomarkers. Circulating microRNAs (miRNAs) have emerged as minimally invasive candidates for cancer detection. This study evaluated the baseline, free-circulating serum expression of miR-181a-5p, miR-214-3p, and miR-223-3p in treatment-naïve patients with EOC and healthy controls. In this single-center prospective case-control study, pretreatment serum samples were collected from 77 patients with histologically confirmed EOC and 74 healthy female controls. miRNA expression was quantified by quantitative real-time PCR using U6 RNA as internal control. Associations with clinicopathologic features and overall survival (OS) were assessed. Diagnostic performance was evaluated using receiver operating characteristic (ROC) analysis. Serum miR-181a-5p and miR-223-3p levels were significantly lower in patients compared with controls (p < 0.001 for both), while miR-214-3p showed no significant difference (p = 0.505). After adjustment for age and BMI, reduced expression of miR-181a-5p and miR-223-3p remained significant. ROC analysis demonstrated moderate diagnostic accuracy for miR-181a-5p (AUC = 0.704) and miR-223-3p (AUC = 0.732). No significant associations were identified between serum miRNA levels and FIGO stage, tumor grade, platinum sensitivity, progression-free survival, or overall survival (all p > 0.05). Serum miR-181a-5p and miR-223-3p are significantly downregulated in EOC and exhibit moderate discriminatory capacity, suggesting that they may warrant further evaluation as components of future multimodal biomarker strategies. Prospective multicenter studies, ideally complemented by paired tissue and exosomal profiling to address compartment-specific dynamics, are warranted to validate these findings.