RESEARCH ARTICLE Inhibition of Ovarian Epithelial Carcinoma Tumorigenesis and Progression by microRNA 106b Mediated through the RhoC Pathway

Epithelial ovarian cancer (EOC) is the most lethal of the gynecological malignancies. Ex-ploring the molecular mechanisms and major factors of invasion and metastasis could have great significance for the treatment and prognosis of EOC. Studies have demonstrat-ed that microRNA 106b (miR-106b) may be a promising therapeutic target for inhibiting breast cancer bone metastasis, but the role of miR-106b in EOC is largely unknown. In this work, miRNA-106b expression was quantified in various ovarian tissues and tumors. Ovari-an carcinoma cell lines were transfected with miR-106b, after which, cell phenotype and ex-pression of relevant molecules was assayed. Dual-luciferase reporter assays and xenograft mouse models were also used to investigate miR-106b and its target gene. MiR-106b mRNA expression was found to be significantly higher in normal ovarian tissues and benign tumors than in ovarian carcinomas and borderline tumors (p< 0.01), and was nega-tively associated with differentiation (Well vs. Por & Mod) and the International Federation of Gynecology and Obstetrics (FIGO) staging (stage I/II vs. stage III/IV) in ovarian carcino-ma (p< 0.05). MiR-106b transfection reduced cell proliferation; promoted G1 or S arres