人胃癌BGC-823细胞中去甲斑蝥素抑癌作用机理的蛋白质组学研究

去甲斑蝥素是我国自行研制的抗肿瘤药物，在临床上主要用于消化道肿瘤的治疗．实验表明，去甲斑蝥素可引起人胃癌BGC-823细胞发生 M期阻滞及细胞凋亡．进一步利用双向电泳和质谱技术，筛选出了去甲斑蝥素抑癌作用相关蛋白．研究显示，线粒体热休克蛋白CH60、线粒体ATP合酶d亚单位、内质网葡萄糖调节蛋白GRP78、线粒体Hsp70的辅助因子GRPE1、SH3L3以及染色质组装因子1小亚基RBBP4参与了去甲斑蝥素的抑癌作用．研究提示，去甲斑蝥素可能通过促进线粒体热休克蛋白及p53的表达进而激活caspase-3依赖的凋亡通路，并且去甲斑蝥素在引发内质网协迫之后，可通过抑制胞外信号调节激酶(extracellular signal regulated kinase, ERK)的活性促进肿瘤细胞的凋亡．进一步分析了去甲斑蝥素与线粒体ATP合酶抑制剂寡霉素A的联合用药对人胃癌细胞生长的影响，结果表明，联合用药的抑瘤效果比单独用药的抑瘤效果显著，提示去甲斑蝥素可能通过抑制线粒体ATP合酶功能抑制BGC-823生长．上述结果为优化去甲斑蝥素的联合用药方案提供了新线索．

Determination of Norcantharidin-associated Proteins by Comparative Proteomic Analysis in BGC-823 Cells

Norcantharidin ( NCTD ) is an effective anti-tumor drug developed by China independently. It has been widely used for clinical therapy especially in digestive tract cancers. It was found that NCTD can induce M arrest and apoptosis in a dose- and time-dependent manner in BGC-823 cell line. In order to reveal the molecular mechanism by which NCTD actions systemically, a comparative analysis of proteomic profiling was conducted between control cells and NCTD treated cells by 2-D and mass spectrum. The results indicated that mitochondrial heat shock protein CH60, ATP synthase d subunit , ER glucose-regulated protein GRP78, mitochondrial Hsp70 related factor GRPE1, SH3 domain-binding glutamic acid-rich-like protein SH3L3 and Histone-binding protein RBBP4 may involve in the antitumor function of NCTD. The result suggested that NCTD might induce caspase-3 dependent apoptosis through promoting the expression of mitochondrial heat shock protein and p53. NCTD can promote the apoptosis by inhibiting the activity of ERK after inducing ER stress. The combinational treatment of BGC-823 cells with oligomycin A, an inhibitor of mitochondrial ATP synthase, and NCTD inhibited the growth of BGC-823 cells more evidently compared with single drug treatment. This result confirmed that NCTD can suppress the growth of BGC-823 by inhibiting the activity of mitochondrial ATP synthase.