Abstract: Background and purpose: miR-101 has been reported to be down-regulated in gastric cancer, colorectal cancer, breast cancer as well as prostate cancer acting as a tumor suppressor gene. However, its function in ovarian cancer is still unknown. The aim of this study was to investigate whether miR-101 can suppress cell growth and invasion of ovarian cancer cells by targeting DNMT3A, so as to reveal molecular mechanism to inhibit ovarian cancer. Methods: Quantitative real-time palymerase chain reaction (qRT-PCR) method was employed to detect the expression of miR-101 in ovarian cancer and cancer adjacent normal ovarian tissues. SKOV3 cells were transfected with miR-101 mimics, and DNMT3A siRNA was transfected as a positive control. Then Western blot was used to detect the expression of DNMT3A protein regulated by miR-101 in SKOV3 cells. The growth and invasion ability of SKOV3 cells were evaluated by MTT and Transwell invasion assays. Results: qRT-PCR showed that miR-101 was down-regulated in ovarian cancer tissues. Western blot showed that the level of DNMT3A protein was inhibited by restored miR-101 or knock-down of DNMT3A in SKOV3 cells. Following transfection of miR-101 mimics or knock-down of DNMT3A for 48, 72 and 96 h respectively, MTT assay showed that the D values were significantly lower than the control group, (P<0.05). After transfection of miR-101 mimics or knock-down of DNMT3A for 36 h, Transwell invasion assay showed that the numbers of cells through the basement membrane was (105±7) and (107±13), respectively, which are significantly different from the control group (213±11), indicating invasion of SKOV3 cells significantly slowed down (P<0.05). Conclusion: miR-101 suppresses cell growth and invasion by targeting DNMT3A in ovarian cancer.

Key words: MiR-101, Ovarian cancer, DNMT3A, Growth and invasion