Diagnostic Value of Serum sST2 and MicroRNA-29a in Ovarian Cancer: A Dual-Biomarker Pilot Study

Ovarian cancer is frequently diagnosed at an advanced stage due to non-specific symptoms, contributing to high mortality. The limited diagnostic performance of current serum assays in early disease underscores the need for complementary circulating biomarkers. Circulating microRNAs and inflammation-related markers are promising candidates. Although miRNAs are implicated in cancer diagnostics, the role of miRNA-29a in ovarian cancer remains underexplored. Given that sST2 is elevated in several malignancies and is a direct target of miRNA-29a, concurrent evaluation may be informative. This pilot study compared serum miRNA-29a and sST2 levels in 23 ovarian cancer patients and 22 healthy female controls. miRNA-29a expression was quantified by real-time PCR (2^-ΔΔCt), and sST2 was measured by ELISA; diagnostic performance was assessed using ROC analysis. miRNA-29a levels were significantly reduced (<i>p</i> < 0.05), whereas sST2 concentrations were significantly increased (<i>p</i> < 0.001) in patients versus controls. ROC analysis showed modest discrimination for miRNA-29a (AUC 0.678) and higher performance for sST2 (AUC 0.825). No significant correlation was observed between the two markers. These findings suggest that circulating miRNA-29a and sST2 may have biomarker potential in ovarian cancer; larger, well-designed studies are required to confirm clinical utility.