MicroRNA-505-3p mediates cell motility of epithelial ovarian cancer via suppressing PEAK1 expression.

MicroRNAs (miRNAs) are a class of small RNA genes with important roles in cancer biology regulation. There are considerable studies regarding the roles of microRNA-505-3p (miR-505-3p) in cancer development and progression, but the function of miR-505-3p in epithelial ovarian cancer (EOC) has not been fully clarified. Comparative analysis of miRNA expression data set was used to select differentially expressed miRNAs. Quantitative real-time polymerase chain reaction was applied to detect expression levels of RNAs, while western blot and immunofluorescence staining were performed to detect expression levels of proteins of interest. The motility of EOC cells was assessed by wound healing and transwell assays. The binding and regulating relationship between miRNA and its direct target gene was investigated by dual-luciferase assay. Our results show that miR-505-3p was upregulated in recurrent EOC, which significantly inhibits EOC cell motility via modulating cell epithelial-mesenchymal transition. Furthermore, our results indicated that PEAK1 expression was inhibited by direct binding of miR-505-3p into its 3'-URT in EOC cells. Importantly, knockdown of PEAK1 attenuated the effect of mi-505-3p inhibitor on EOC cell migration and invasion. In conclusion, our findings indicate that miRNA-505-3p inhibits EOC cell motility by targeting PEAK1.