Abstract
Serous ovarian carcinoma (SOC) is frequently diagnosed at advanced stages and is associated with poor clinical outcomes, highlighting the urgent need for reliable diagnostic and prognostic biomarkers. Long non-coding RNA MEG3 and the autophagy-related protein Beclin-1 are recognized tumor suppressors; however, their combined diagnostic relevance in SOC remains insufficiently explored. This case-control study included 24 patients with histopathologically confirmed SOC. Paired tumor and adjacent non-tumorous ovarian tissues were analyzed for lncRNA MEG3 expression using quantitative real-time PCR and for Beclin-1 protein expression using immunohistochemistry. Serum CA-125 levels were assessed by ELISA. Associations with clinicopathological parameters were evaluated, and diagnostic performance was analyzed using receiver operating characteristic (ROC) curves. Both lncRNA MEG3 and Beclin-1 were significantly downregulated in SOC tissues compared with adjacent non-cancerous tissues (P < 0.0001). Reduced expression was significantly associated with tumor grade and ascites. The relationship with FIGO stage was not uniform in this cohort and should be interpreted cautiously because of the small sample size and unequal distribution of early and advanced cases. Beclin-1 expression was notably higher in premenopausal patients and in well to moderately differentiated tumors. A strong positive correlation was observed between lncRNA MEG3 and Beclin-1 expression (r = 0.96, P < 0.001), indicating a strong statistical association rather than a proven regulatory interaction. ROC curve analysis suggested diagnostic potential for lncRNA MEG3, Beclin-1, and serum CA-125. The concurrent downregulation of lncRNA MEG3 and Beclin-1 in SOC tissues suggests that these markers may serve as promising complementary biomarkers. However, their clinical utility should be considered preliminary and requires validation in larger, multicenter cohorts with functional studies before routine clinical application can be recommended.