蛋白酶体抑制剂通过内质网应激途径诱导卵巢癌细胞凋亡的研究

Study on apoptosis of ovarian cancer cells induced by proteasome inhibitor via endoplasmic reticulum stress

目的:探讨内质网应激在蛋白酶体抑制剂MG132诱导卵巢癌细胞凋亡中的作用。方法:将人卵巢癌细胞系SKOV3设空白对照组、不同浓度MG132处理组、生长停滞及DNA损伤(chop)基因siRNA组、随机序列核酸siRNA组4组。四唑盐比色法和流式细胞术检测细胞活力和凋亡率;实时定量PCR和Western blot检测各组细胞葡萄糖调节蛋白78(grp78)以及chop基因的mRNA和蛋白表达。结果:MG132处理抑制SKOV3细胞活力,增加SKOV3细胞凋亡率。MG132处理还可诱导SKOV3细胞grp78和chop基因的表达。当chop siRNA靶向沉默chop表达后,MG132作用后SKOV3细胞活力明显增加。结论:MG132诱导卵巢癌细胞内质网应激;chop基因介导内质网应激凋亡途径在MG132的抗卵巢癌活性中发挥重要作用。

Objective： To investigate the role of endoplasmic reticulum （ER） stress in ovarian cancer cell apoptosis induced by MG132. Methods： SKOV3 ovarian cancer cells were divided into control group and different concentrations of MG132-treated groups also divided into random small interfering RNA （siRNA） and siRNA specific against chop （sichop）. The cells were treated with MG132, cell viability and apoptotic cells were evaluated using MTT assay and flow cytometry, respectively. The grp78 and chop mRNA and protein levels were analyzed using real-time reverse tran- scription polymerase chain reaction and western blot, respectively. Results.. The treatment with MG132 decreased cell viability and increased apoptotic rate. MG132 dose-dependently increased grp78 and chop mRNA and protein expression levels in SKOV3 cells. Knockdown chop induction by sichop significantly increased the viability of SKOV3 cells upon MG132 exposure. Conclusion： MG132 induces ER stress in ovarian cancer cells. The chop-mediated apoptotic signal of ER stress might play a critical role in MG132-induced cytotoxicity of ovarian cancer cells.