Dysregulated Long Non-Coding RNA DANCR in Polycystic Ovary Syndrome Drives Granulosa Cell Apoptosis and Contributes to Ovarian Dysfunction via miR-185-5p.

This study investigates the expression patterns of lncRNA differentiation antagonizing non-protein coding RNA (DANCR) and microRNA (miR)-185-5p, and their potential roles in the pathogenesis of polycystic ovary syndrome (PCOS). Involved 100 patients with PCOS as the case group and 80 non-PCOS patients with fallopian tube diseases as the control group. The relative levels of serum DANCR and miR-185-5p were detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Pearson's method was performed to estimate the correlation between DANCR and abnormal indicators in the PCOS group. The effects of DANCR and miR-185-5p on cell viability and apoptosis were evaluated by Cell Count Kit (CCK)-8 assay and flow cytometry. The target relationship between DANCR and miR-185-5p was verified via a luciferase reporter assay. Compared with the control group, DANCR expression was elevated, while miR-185-5p levels were reduced in the serum of patients with PCOS. When further grouped, patients with PCOS and insulin resistance (IR) showed higher DANCR levels and lower miR-185-5p levels than those without IR. Receiver operator characteristic (ROC) curve analysis displayed that the sensitivity and specificity of DANCR to distinguish PCOS from control groups were 74.0% and 88.7%, respectively. In KGN cells, down-regulation of DANCR expression enhanced cell viability and suppressed cell apoptosis by elevating miR-185-5p levels. Luciferase reporter gene assays confirmed that miR-185-5p directly targeted DANCR and was negatively regulated by DANCR. Our findings suggest that dysregulated upregulation of DANCR might promote granulosa cell apoptosis and impair cell viability by repressing miR-185-5p, thereby exacerbating POCS progression.