mda-7／IL-24通过内质网应激通路诱导肝癌细胞生长抑制和凋亡  

mda-7/IL-24 induces apoptosis of hepatic carcinoma cells through endoplasmic reticulum stress pathway

作　　者：张小峰[1] 施乐华[1] 艾莉[1] 康晓燕[2] 温莹浩[2] 钱海华[2] 张妤[2] 殷正丰[2] 

机构地区：[1]第二军医大学东方肝胆外科医院综合治疗科,上海200438 [2]第二军医大学东方肝胆外科医院分子肿瘤实验室,上海200438

出　　处：《第二军医大学学报》2008年第9期1020-1024,共5页Academic Journal of Second Military Medical University

基　　金：国家自然科学基金(30500477);国家重点基础研究发展计划(“973”计划,2002CB513100)~~

摘　　要：目的:观察mda-7/IL-24对不同类型的肝肿瘤细胞及正常肝脏细胞增殖及凋亡的影响并探讨其可能的作用机制。方法:构建携带mda-7基因的重组腺病毒Ad-mda-7,转染肝癌细胞系HepG2、Hep3B、PLC/PRF/5和正常肝细胞L02,MTT法和流式细胞术检测细胞增殖及凋亡情况,Western印迹检测细胞相关蛋白的表达。应用钙蛋白酶抑制剂Ⅰ(ALLN,25μmol/L)预处理上述细胞30min,观察阻断内质网应激通路后上述指标的变化。结果:MTT法和流式细胞术检测结果表明,与感染Ad-GFP比较,Ad-mda-7选择性抑制肝癌细胞生长(P<0.01),诱导肝癌细胞凋亡(P<0.01,其中对HepG2细胞影响最明显),而对正常肝细胞生长无明显影响;ALLN预处理能部分抑制Ad-mda-7的上述作用。Western印迹结果表明Ad-mda-7能诱导HepG2细胞BiP/GRP78、Bax蛋白高表达(P<0.01),caspase-12、caspase-3活化及p38 MAPK磷酸化;ALLN预处理能抑制Ad-mda-7转染引起的Bax蛋白高表达及caspase-12、caspase-3活化;而对BiP/GRP78的高表达及p38 MAPK磷酸化无影响。结论:mda-7/IL-24可能通过内质网应激通路诱导肝癌细胞生长抑制和凋亡。Objective： To study the effects of mda-7/IL-24 on the growth, proliferation, apoptosis of different hepatic carcinoma cell lines and the related mechanisms. Methods： A recombinant adenovirus Ad-mda-7 was constructed and was used to transfect human hepatic carcinoma cell lines （HepG2, Hep3B and PLC/PRF/5） and normal liver cell line L02. MTT assay and FACS were employed to assess the growth and apoptosis of cells; the expression of related protein expression was examined by Western blotting. The cells were treated with calpastatin I （ALLN,25 umol/L） for 30 min to block the endoplasmic reticulum stress （ER-stress） and the above indices were examined again. Results： Treatment with Ad-mda-7 resulted in selective inhibition of cell proliferation and induced apoptosis, especially in HepG2 cells; Ad-mda-7 showed no influence on normal cells. Pretreatment with ALLN partially inhibited the above effects of Ad-mda-7. Western blotting revealed that Ad-mda-7 induced upregulation of BiP/GRP78 and Bax protein, activation of caspase-12, caspase-3 and phosphorylation of p38 MAPK in HepG2 ceils. Blocking ER-stress with ALLN down-regulated Bax, caspase-12 expression and inhibited activation of caspase-3 and easpase-12,but showed no effect on the expression of BiP/GRP78 or phosphorylation of p38 MAPK. Conclusion： mda-7/IL-24 can cause growth inhibition and promote apoptosis of hepatic carcinoma cells through the ER-stress pathway.

关 键 词：mda-7基因 内质网 应激 细胞凋亡 肝肿瘤 

分 类 号：R735.7[医药卫生—肿瘤]