[MicroRNA-16 regulates the proliferation, invasion and apoptosis of ovarian epithelial carcinoma cells in vitro].

OBJECTIVE: To study the role and mechanism of microRNA-16 (miR-16) in the proliferation, invasion and apoptosis of ovarian epithelial carcinoma cells in vitro.

METHODS: The SKOV-3 cells were transfected with miR-16 mimics or negative control RNA (NC) by lipofectamine 2000. The expression of miR-16 was detected by real-time reverse transcription (RT)-PCR in SKOV-3 cells, and western blot was used to detect the expression of vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2) and bcl-2 protein. Methyl thiazolyl tetrazolium (MTT), 5-ethynyl-2'-deoxyuridine (EdU) and transwell assay were used to determine the proliferation and invasion abilities. And the rate of apoptotic cell was detected by flow cytometry method.

RESULTS: (1) The expression level of miR-16 in the transfection cells group was significantly higher than that in NC group (125.93 ± 15.30 versus 0.78 ± 0.16, P < 0.01). (2) The relative expression level of VEGF protein in transfection cells, NC and blank control group was 0.58 ± 0.05, 1.22 ± 0.03, 1.20 ± 0.03, MMP-2 protein was 0.63 ± 0.03, 1.16 ± 0.03, 1.21 ± 0.03, and bcl-2 protein 0.52 ± 0.03, 1.19 ± 0.05, 1.28 ± 0.06, respectively. The level of VEGF, MMP-2 and bcl-2 protein in the transfection group were lower than those in other control groups, and there were significantly differences among them (all P < 0.01). (3) After transfected 4 days, the inhibition rate of cell proliferation in the transfection group was dramatically higher than that in NC group [(37.2 ± 6.2)% versus (3.6 ± 3.2)%, P = 0.001]. (4) The percentage rate of proliferative cells in the transfection, NC and blank control group was (12.3 ± 0.8)%, (23.4 ± 1.8)%, (31.1 ± 4.9)%. And it was lower in the transfection group (P < 0.05). (5) Decreased cells via the transwell member in the transfection group (6 ± 3) were detected as compared with NC group (40 ± 9) and blank control group (48 ± 8, P < 0.01). (6) Twenty-four hours after cultured in serum starvation and hypoxia, the rate of the viable and late apoptotic cells in the transfection group were significantly higher than those in NC group and blank control group [the rate of viable apoptotic cell was (16.9 ± 2.1)%, (10.3 ± 1.7)% and (9.0 ± 0.8)% respectively, P < 0.01; the rate of late apoptotic cell was (13.4 ± 3.3)%, (3.2 ± 1.8)% and (0.7 ± 0.6)% respectively, P < 0.01]. After cultured 48 hours, total apoptotic cells in the transfection group was significantly more than those in other groups (P < 0.01).

CONCLUSION: miR-16 might inhibit the proliferation, invasion of ovarian epithelial carcinoma cells and enhance their sensitivity to apoptotic stimuli via downregulation of the expression of VEGF, MMP-2 and bcl-2 protein.