DR5上调在5，7-二甲氧基黄酮增敏TRAIL诱导肝癌细胞凋亡中的作用

目的 研究5,7-二甲氧基黄酮(5,7-DMF)是否能增强人肝癌细胞对肿瘤坏死因子相关凋亡诱导配体(TRAIL)介导细胞凋亡的敏感性及其作用机制.方法 体外培养人肝癌Hep 3B细胞.MTT法测定细胞毒性;碘化丙啶(PI)染色流式细胞术(FCM)和DNA琼脂糖凝胶电泳检测细胞凋亡;免疫酶联吸附法测定caspase-3和caspase-8的活性.Western blot 分析DR4和DR5表达.结果 5,7-DMF能增强Hep 3B细胞对TRAIL诱导凋亡的敏感性和诱导DR5表达.5,7-DMF与TRAIL合用诱导Hep 3B细胞凋亡依赖于caspase-3和caspase-8活化.DR5特异拮抗性嵌合抗体减弱5,7-DMF增强TRAIL诱导Hep 3B细胞凋亡作用.结论 5,7-DMF通过上调DR5增强TRAIL诱导人肝癌细胞凋亡.

Role of DR5 Upregulation on 5,7-dimethoxyflavone Sensitizing TRAIL-Induced Apoptosis in Hepatocellular Carcinoma Cells

ObjectiveTo examine whether 5,7-dimethoxyflavone (5,7-DMF) sensitizes human hepatocellular carcinoma (HCC) cells to tumor necrosis factor-related apoptosis inducing ligand (TRAIL)-mediated apoptosis and its mechanism.MethodsHuman hepatocellular carcinoma Hep3B cells were cultured in vitro.The cytotoxic activity was determined using MTT assay.The apoptotic cell death was examined by Flow cytometry using PI staining and DNA agarose gel electrophoresis.The activities of caspase-3 and -8 were measured using ELISA.The expression of DR4 and DR5 were analyzed using western blot.Results5,7-DMF sensitized Hep 3B cells to TRAIL-induced apoptosis and induced the death receptor 5 (DR5) expression.Induction of apoptosis by the cotreatment with 5,7-DMF and TRAIL was dependent on activation of caspase-3 and -8.5,7-DMF-mediated sensitization of Hep 3B cells to TRAIL was reduced by administration of a blocking antibody for DR5.Conclusion5,7-DMF enhances TRAIL-induced apoptosis by DR5 upregulation in HCC.