Effect of microRNA-206 on the growth of prostate cancer cells by interfering with the expression of CDK4 and GAK / 国际肿瘤学杂志

ABSTRACT

Objective To investigate the effect of microRN-206 (miR-206) on the expression of Cyclin-dependent kinase 4 (CDK4) and Cyclin G-associated protein kinase (GAK), and the growth of prostate cancer cells.Methods Prostate cancer cell lines DU-145 and PC-3 were transfected with miR-NC (the control group) or miR-206 (the experimental group).The expressions of CDK4 and GAK mRNA were detected by real-time quantitative PCR (qRT-PCR).The expressions of CDK4 and GAK protein were detected by Western blotting.Cell cycle distribution was detected by flow cytometry.EdU proliferation assay and colony forming assay were used to analyze the cell proliferation ability.Results In DU-145 and PC-3 cells, the expressions of CDK4 mRNA in miR-NC group were 1.00±0.09, 1.00±0.10, the expressions of GAK mRNA were 1.00±0.05, 1.00±0.06.The expressions of CDK4 mRNA in miR-206 group were significantly decreased in DU-145 (0.36±0.18;t=6.572, P=0.001) and PC-3 cell lines (0.43±0.17;t=5.794, P=0.001).The expressions of GAK mRNA were also significantly decreased in DU-145 (0.23±0.04;t=22.420, P<0.001) and PC-3 cell lines (0.32±0.08;t=14.500, P<0.001).Western blotting results were consistent with qRT-PCR results.The results of flow cytometry showed that compared with the miR-NC group of DU-145 and PC-3 cell lines, the percentage of cells in S phase (23.60%±5.68% vs.32.53%±4.52%, t=2.462, P=0.049;22.09%±4.35% vs.30.96%±4.86%, t=2.720, P=0.035) and G2-M phase (16.28%±7.12% vs.26.63%±4.33%, t=2.484, P=0.048;14.60%±1.62% vs.24.68%±7.13%, t=2.758, P=0.033) decreased after transfection of miR-206, and the percentage of cells in G0-G1 phase (60.13%±5.82% vs.40.84%±5.37%, t=4.872, P=0.003;63.31%±3.27% vs.44.36%±3.82%, t=7.533, P<0.001) increased.The results of EdU proliferation assay showed that the proliferation abilities were significantly attenuated after transfection of miR-206 (22.56±3.81 vs.38.90±8.51, t=3.503, P=0.013;25.12±6.42 vs.48.45±8.92, t=4.244, P=0.005).The results of colony formation experiments showed that the numbers of colonies formed by DU-145 and PC-3 in miR-NC group were 218.66±44.59 and 177.35±24.49, respectively.The numbers of colonies formed in miR-206 group were 125.38±32.80 (t=3.370, P=0.015) and 82.65±14.05 (t=6.708, P=0.001), suggesting that cell proliferation ability in miR-206 group was reduced.Conclusion miR-206 significantly inhibits the growth of prostate cancer cells by interfering with the expressions of CDK4 and GAK, suggesting that miR-206 may be a molecular targeted therapy tool for prostate cancer.