ABSTRACT
@#[Abstract] Objective: To study the effect of microRNA-141(miR-141) expression regulation on cell proliferation, cell cycle, apoptosis, invasion and migration of human prostate cancer cell line DU145 and its mechanism. Methods: MiR-141 mimics (miR-141 up group) and miR-141 inhibitors (miR-141 down group) were transfected into human prostate cancer DU145 cells by using liposome lipofectamine 2000, and the un-transfection group (Control group) and non-sense miRNA sequence transfection group (NC group) were set. The expression of miRNA-141 in DU145 cells in each group before and after transfection was detected by qPCR. MTT assay was used to detect the proliferation viability and sensitivity to cisplatin (DDP) in DU145 cells of each group. Cell cycle and apoptosis rate of DU145 cells under DDP treatment were detected by Flow cytometry; the changes in cell invasion and migration ability were detected by Transwell method. The protein expressions of VEGF and EGFR in DU145 cells of each group were detected by Western blotting. Results: Compared with the Control and NC group, the level of miRNA-141 expression in the miR-141-down group decreased to (0.18±0.08), the cell proliferation viability decreased significantly while its sensitivity to DDP increased significantly, the cell cycle was blocked in the G0+G1 phase, and the apoptosis rate significantly increased to (46.67±5.86)% while cell invasion rate and migration rate significantly decreased to (44.34±8.32)%, (57.73±6.19)%, and the relative expression levels of VEGF and EGFR decreased to (0.47±0.06), (0.36±0.06), (P<0.05 or P<0.01). But in the miR-141-up group, the level of miRNA-141 expression increased to (4.23±0.53), the cell proliferation viability significantly increased while its sensitivity to DDP decreased significantly, and the cell cycle was promoted into S and G2 phase, the apoptosis rate significantly decreased to (18.77±4.24)% while cell invasion and migration rate significantly increased to (89.94±6.34)%, (94.44±5.84)%, and the relative expression levels of VEGF and EGFR were up to (0.89±0.07), (0.73±0.06),(P<0.05 or P<0.01). Conclusion: miR-141 can act as a growth promoting factor in prostate cancer DU145 cells. miR-141 down-regula‐tion can significantly inhibit the proliferation viability, cell cycle, migration and invasion of DU145 cells, and promote cell apoptosis and DDP-sensitivity, and the mechanism of which may be related with inhibition of VEGF and EGFR protein expressions.