Toll样受体7在人胃癌细胞株中的表达及其激动剂诱导SGC-7901细胞发生凋亡的实验研究  

Expression of Toll-like receptor 7 in gastric cancer cell lines and effects of TLR7 agonist on proliferation and apoptosis of SGC-7901 cells in vitro

作　　者：姜炅[1] 董蕾[1] 秦斌[1] 郭晓燕[1] 李红[1] 史海涛[1] 刘亚萍[2] 

机构地区：[1]西安交通大学医学院第二附属医院消化内科,陕西西安710004 [2]西安交通大学医学院第一附属医院消化内科,陕西西安710061

出　　处：《南方医科大学学报》2014年第11期1606-1610,共5页Journal of Southern Medical University

基　　金："十二五"国家科技支撑计划(2012BAJ18B03-03)~~

摘　　要：目的探讨Toll样受体7（TLR7）在不同人胃癌细胞株中的表达及其激动剂咪喹莫特对SGC-7901细胞增殖和凋亡的影响。方法 Western blot法检测3种胃癌细胞株（SGC-7901、HGC-27和MKN-28）中TLR7蛋白表达差异,选取高表达TLR7的胃癌细胞作为主要研究对象;MTT法考察不同浓度咪喹莫特处理TLR7高表达胃癌细胞12～72 h后细胞增殖活性的改变;流式细胞仪AnnexinV-FITC/PI双染色法观察100μg/ml咪喹莫特干预12及24 h后细胞早期凋亡比率的改变;透射电镜下观察细胞凋亡形态学改变;实时定量PCR法分析Bcl-2及Bax mRNA在咪喹莫特作用前后表达差异。结果 TLR7蛋白在SGC-7901中表达水平高于其他两种胃癌细胞,其激动剂咪喹莫特能够明显抑制SGC-7901细胞增殖并且呈现出浓度及时间依赖性;100μg/ml咪喹莫特干预24 h后SGC-7901细胞早期凋亡比率明显上升,透射电镜下可观察到典型的凋亡形态学改变;咪喹莫特处理后SGC-7901细胞Bcl-2 mRNA表达呈浓度依赖性下降,Bax mRNA呈浓度依赖性上升。结论 TLR7在3种不同分化程度的胃癌细胞中均有表达,其激动剂咪喹莫特能够明显抑制SGC-7901细胞增殖并诱导其凋亡。Objective To investigate the expression of Toll- like receptor 7（TLR7） in gastric cancer cell lines and the effect of imiquimod, a TLR7 agonist, on the proliferation and apoptosis of SGC-7901 cells. Methods The protein expression levels of TLR7 were detected with Western blotting in 3 human gastric cancer cell lines（SGC-7901, HGC-27 and MKN-28）. The cell line expressing the highest TLR7 level was exposed to different doses of imiquimod for 12-72 h and the cell viability was assessed with MTT assay. The cell apoptosis rate after 100 μg/ml imiquimod treatment for 12 or 24 h was quantified by flow cytometry,and the ultrastructual changes of the cells were observed under electron microscope. The expression of apoptosis-related genes Bcl-2 and Bax were analyzed with real-time PCR. Results All the 3 cell lines expressed TLR7, among which SGC-7901 cells showed the highest expression level. TLR7 agonist imiquimod dose- and time-dependently reduced the viability of SGC-7901 cells. Exposure to 100 μg/ml imiquimod for 24 h resulted in SGC-7901 cell apoptosis as shown by an increased ratio of early apoptotic cells and significant ultrastructural changes of the cells. Real-time PCR demonstrated that imiquimod treatment for24 h caused a dose-dependent reduction of Bcl-2 mRNA expression and increment of Bax mRNA expression. Conclusion TLR7 protein is expressed in all the 3 gastric cancer lines and its agonist imiquimod can inhibit cell proliferation and induce apoptosis in SGC-7901 cells.

关 键 词：胃癌 TOLL样受体7 咪喹莫特 凋亡 

分 类 号：R735.2[医药卫生—肿瘤]