miRNA141表达的调控对人前列腺癌DU145细胞恶性生物行为的影响

Effect of regulating miRNA141 expression on malignant biological behaviors of human prostate cancer DU145 cells

目的:研究microRNA-141(miR-141)表达的调控对人前列腺癌细胞系DU145细胞增殖、周期、凋亡、侵袭和迁移等恶性生物学行为的影响及其作用机制。方法:利用脂质体Lipofectamine2000将miR-141 mimics(miR-141 up组)和miR-141 inhibi-tiors(miR-141 down组)分别转染至人前列腺癌DU145细胞中,同时设置未转染组(Control组)和miRNA无义序列转染组(NC组)。qPCR检测转染前后各组DU145细胞中miR-141表达变化,MTT方法检测各组DU145细胞的增殖活力和对顺铂(DDP)作用敏感性变化,流式细胞术检测各组DU145细胞周期和顺铂作用下凋亡率变化,Transwell方法检测各组细胞侵袭和迁移能力的变化,Western blotting检测各组细胞中VEGF、EGFR蛋白表达量变化。结果:与Control组和NC组相比,miR-141 down组DU145细胞中miRNA-141表达水平下降为(0.18±0.08),其细胞增殖活力显著下降而对DDP敏感性显著上升、细胞周期被阻滞于G0+G1期而细胞凋亡率显著上升至(46.67±5.86)%、细胞侵袭率和迁移率分别显著下降至(44.34±8.32)%和(57.73±6.19)%、VEGF和EGFR相对表达量分别下降至(0.47±0.06)和(0.36±0.06)(上述各指标分别P<0.05或P<0.01)。miR-141 up组DU145细胞中miR-NA-141表达水平上升为(4.23±0.53),其细胞增殖活力显著上升而对DDP敏感性显著下降、细胞周期提前进入S和G2期而细胞凋亡率显著下降至(18.77±4.24)%、细胞侵袭率和迁移率分别显著上升至(89.94±6.34)%和(94.44±5.84)%、VEGF和EGFR相对表达量分别上升至(0.89±0.07)和(0.73±0.06)(上述各指标分别P<0.05或P<0.01)。结论:miR-141在前列腺癌DU145细胞中发挥促癌因子作用,其下调表达能够显著抑制DU145细胞增殖活力、周期、侵袭与迁移,而促进对DDP的敏感性和细胞凋亡,其机制可能与其抑制VEGF和EGFR蛋白表达有关。

Objective:To study the effect of microRNA-141(miR-141)expression regulation on cell proliferation,cell cycle,apopto-sis,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 lipo-fectamine 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 in-creased 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.