甲基化CpG结合结构蛋白2在胃癌的表达及靶向抑制  

Expressions of methyl-CpG-binding domain protein 2 in gastric cancer and their RNA interferences

作　　者：范晶[1] 何苗[2] 幸宇[3] 王子卫[2] 

机构地区：[1]重庆医科大学附属第一医院急诊科 [2]重庆医科大学附属第一医院胃肠外科 [3]重庆医科大学基础医学院法医学教研室,重庆400016

出　　处：《重庆医科大学学报》2013年第9期969-973,共5页Journal of Chongqing Medical University

基　　金：国家自然科学基金资助项目(编号:81202385)

摘　　要：目的:研究甲基化CpG结合结构蛋白2(methyl-CpG-binding domain protein 2,MBD2)在胃癌的表达及靶向抑制。方法:免疫组化法对40例胃癌及配对胃黏膜组织,免疫荧光法对胃癌细胞SGC-7901行MBD2表达研究。构建3个靶向抑制MBD2的siRNA(MBD2-siRNA-1、MBD2-siRNA-2、MBD2-siRNA-3)。转染MBD2-siRNA入SGC-7901,RT-PCR及Western blot验证MBD2的抑制效果。噻唑蓝比色法检测SGC-7901增殖率。结果:胃癌组织MBD2表达较对照胃黏膜组织增强(χ2=6.646,P=0.010);且低分化胃癌与伴幽门螺杆菌感染的胃癌中MBD2表达更强(χ2值分别为9.730、8.700,P值分别为0.01和0.04)。MBD2蛋白在胃癌胞核分布。MBD2-siRNA可成功转染SGC-7901,并成功筛选靶向抑制MBD2的siRNA(MBD2-siRNA-2)。发现转染MBD2-siRNA-2后96 h,SGC-7901增值率被抑制。结论:MBD2在胃癌表达增强,抑制MBD2可能抑制胃癌增殖。Objective：To investigate the expressions of methyl-CpG-binding domain protein 2 （MBD2） and their RNA interfer ences （RNAi） in gastric cancer. Methods ：Immunohistochemistry was used to detect MBD2 expressions in tissues of 40 gastric can cer cases and matched non-cancerous tissues. Immunofluorescence was used to detect the MBD2 distribution in gastric cancer cell （SGC- 7901）. Three siRNAs （MBD2-siRNA-1, MBD2-siRNA-2, MBD2-siRNA-3） targeting MBD2 were designed. LipofectamineTM2000 was used to transfect MBD2-siRNAs into SGC-7901. RT-PCR and Western blot were used to evaluate the efficiency of MBD2 inhibition. MrIT assay was carried out to detect the growth rate of SGC-7901. Results：Expressions of MBD2 were higher in gastric cancer tissues than in matched gastric mucosa tissues（X2=6.646,P=0.010）. MBD2 expressions were much higher in gastric cancer tissues with low histological grade and H.pylori infection（x2=9.730,8.700 ;P=-0.01,0.04）. MBD2 protein was distributed in nucleus of gastric cancer cell. Three MBD2-siRNAs all could be transfected into SGC-7901 perfectly and MBD2-siRNA-2 could inhibit the MBD2 mRNA and protein expressions best. At last, 96 h after the MBD2-siRNA-2＇s transfection, growth rate of SGC-7901 was inhibited. Conclusions： MBD2 protein expresses higher in astric cancer tissues. MBD2 inhibition could suppress the proliferation of gastric cancer cell.

关 键 词：甲基化CpG结合结构蛋白2 胃癌 RNA干扰 表观遗传 

分 类 号：R735.2[医药卫生—肿瘤]