DNA甲基转移酶1对前列腺癌细胞增殖和迁移侵袭的影响

Expression of DNA methyltransferase 1 in prostate cancer and the effect on cell proliferation and invasion in vitro

目的:探究DNA甲基转移酶1(DNMT1)对前列腺癌细胞增殖和迁移侵袭的影响。方法:采用小干扰RNA(siRNA)沉默前列腺癌细胞株(PC3和DU145)中DNMT1表达,通过定量聚合酶链反应(qPCR)和蛋白质印迹法(Western blot)检测沉默效率。细胞计数试剂盒(CCK-8)检测细胞的体外增殖能力;TransWell检测细胞体外迁移和侵袭能力;Western blot检测si-DNMT1细胞后上皮-间充质转化(EMT)相关蛋白表达。组间比较采用t检验。结果:qPCR和Western blot实验结果显示DNMT1在前列腺癌细胞中高表达,并成功构建siDNMT1 PC3和DU145细胞系。4 d后,CCK-8结果显示,siDNMT1细胞增殖能力低于相应对照组[PC3:1.27±0.71和1.44±0.48比1.66±0.58,t=7.268、5.108,P<0.01;DU145:1.43±0.12和1.27±0.10比1.80±0.06,t=4.841、7.493、P<0.01]。Transwell显示,与对照组细胞比较,siDNMT1细胞迁移和侵袭能力降低(P<0.05)。Western blot结果显示,沉默DNMT1后E-钙黏蛋白(E-cadherin)表达升高,而N-钙黏蛋白(N-cadherin)和波形蛋白(Vimentin)表达水平下降。结论:DNMT1在前列腺癌中高表达,沉默DNMT1后可有效抑制前列腺癌细胞增殖和侵袭迁移能力。

Objective To explore the effect of DNA methyltransferase 1(DNMT1)on the proliferation,migration and invasion of prostate cancer cells,and explore its mechanism.Methods Small interfering RNA(siRNA)was used to silence DNMT1 in prostate cancer cell lines(PC3 and DU145),and the silencing efficiency was evaluated using quantitative polymerase chain reaction(qPCR)and Western blotting assay.Cell counting kit-8(CCK-8)and Transwell assays were used to detected the changes in biological behaviors of prostate cancer cells.Western blotting was used to detect the expression of epithelial-mesenchymal transition(EMT)-related proteins.T-test was used for comparison between groups.Results The expression of DNMT1 in DU145 and PC-3 cells was higher than that in WPMY-1 cells(P<0.05).Down-regulation of the expression of DNMT1 in PC3 and DU145 cells significantly inhibited cell proliferation,invasion and migration(P<0.01).Silencing DNMT1 in prostate cancer cells increased the expression of E-cadherin,while the expression of N-cadherin and Vimentin decreased.Conclusion The expression of DNMT1 in prostate cancer is higher than that in normal prostate.Silencing DNMT1 inhibited the proliferation、invasion and migration of prostate cancer cells.