siRNA沉默MEKK3基因促进TRAIL诱导乳腺癌MCF-7细胞的凋亡

MEKK3-targeted siRNA combined with TRAIL induces apoptosis of breast cancer cell line MCF-7

目的:研究抑制促分裂原活化蛋白激酶/细胞外信号调节激酶-激酶3(mitogen-activated protein/extracellular signal regulated kinase-kinase 3,MEKK3)基因表达促进TRAIL诱导乳腺癌MCF-7细胞凋亡的作用,寻找乳腺癌临床治疗新策略。方法:应用MTT法检测人TRAIL对MCF-7细胞生长的抑制作用。合成MEKK3-siRNA,应用脂质体介导MEKK3-siRNA转染入人乳腺癌细胞MCF-7,以RT-PCR和Western blotting法检测MCF-7细胞MEKK3 mRNA和蛋白的表达。应用MTT法和流式细胞术检测MEKK3-siRNA与TRAIL联合处理后MCF-7细胞的增殖和凋亡。结果:TRAIL具有抑制MCF-7细胞增殖作用,但其抑制作用较弱。MEKK3-siRNA转染后能有效而稳定地抑制MCF-7细胞中MEKK3 mRNA和蛋白的表达(P<0.01)。TRAIL与MEKK3-siRNA联合处理MCF-7细胞较TRAIL单独处理更明显地抑制细胞增殖活力(P<0.05),更明显地增加细胞凋亡率(P<0.01)。结论:siRNA沉默MEKK3基因能显著促进TRAIL对乳腺癌MCF-7细胞凋亡的诱导作用,为探讨乳腺癌治疗新方案提供了实验依据。

Objective： To investigate the promoting effect of silencing mitogen-activated protein/ERK kinase kinase 3 （ MEKK3 ） gene on TRAIL - induced apoptosis of breast cancer MCF-7 cells, so as to search for a novel clinical treatment strategy for breast cancer. Methods： TRAIL was used to treat MCF-7 cells and the growth inhibition of MCF-7 cells was determined by a methyl thiazolyl tetrazolium （ MTT ） assay. Chemically synthesized small interfering RNA （ siRNA ） targeting MEKK3 was transfected into MCF-7 cells using DharmaFECT Transfection reagent, and the expression of MEKK3 mRNA and protein was detected by RT-PCR and Western blotting. The proliferation and apoptosis of MCF-7 cells were analyzed by MTT and flow cytometry （ FCM ） after treatment with MEKK3-siRNA combined with TRAIL. Results： TRAIL inhibited the proliferation of MCF-7 cells, but the inhibitory effect was weak. Transfection with MEKK3-siRNA effectively and stably inhibited the expression of MEKK3 mRNA and protein expression （ P 〈 0.01 ）. Combination of TRAIL and MEKK3-siRNA more severely inhibited the proliferation of MCF-7 cells compared with TRAIL alone （ P 〈 0.05 ） ; besides, the combination also increased the apoptosis rate of MCF-7 cells （ P 〈 0.05 ）. Conclusion： Silencing of MEKK3 gene with siRNA can greatly promote TRAIL-induced apoptosis of breast cancer cells MCF-7, which lays an experimental foundation for new treatment method of breast cancer.