Abstract: Background and purpose: Although cisplatin-based chemotherapies are used as the first-line treatment for ovarian cancers, the majority of patients eventually progress with platinum-resistant disease. miR-483-5p is overexpressed in lung cancer. However, the research on miR-483-5p in epithelial ovarian cancer (EOC) is still unclear. This study aimed to investigate the expression of miR-483-5p in EOC and its effects on cisplatin resistance in EOC cells. Methods: This study analyzed the expression of the miR-483-5p by real-time fluorescent quantitative polymerase chain reaction (RTFQ-PCR) in EOC tissues, normal ovarian tissues, and EOC cells. The role of miR-483-5p in EOC was evaluated in vitro by lentivirus-mediated knockdown of miR-483-5p or overexpression of miR-483-5p in EOC cell lines. Drug sensitivity assay was carried out by CCK-8 kit. Results: miR-483-5p was upregulated in EOC tissues as compared with normal tissues (P<0.01). Furthermore, miR-483-5p expression in advanced stage (Ⅲ–Ⅳ) EOC was significantly higher than that in early stage (Ⅰ–Ⅱ) EOC (P<0.05). Interestingly, miR-483-5p expression was higher in cisplatin-resistant A2780/CP cells than other cells. Increased miR-483-5p expression caused EOC cell resistance to cisplatin and downregulated the expression of p21 and Bcl-2, whereas reduced miR-483-5p expression induced its sensitivity and upregulated the expression of p21 and Bcl-2. Conclusion: The results suggest that miR-483-5p is highly expressed in EOC and contributes to cisplatin resistance. Thus, miR-483-5p is a potential therapeutic target for ovarian cancer.

Key words: Epithelial ovarian cancer, miR-483-5p, Cisplatin, Drug resistance