ERK/MAPK通路参与肝癌产生多药耐药的胞内信号传导  

The role of extraceHular signal-regulated kinase/mitogen-activated protein kinase pathway in mulfidrug resistance of hepatoeellular carcinoma

作　　者：朱虹[1] 陈孝平[2] 罗顺峰[2] 关剑[2] 张万广[2] 张必翔[2] 茅彩萍[1] 

机构地区：[1]苏州大学医学院基础医学系,215006 [2]华中科技大学同济医学院附属同济医院肝胆胰外科研究所

出　　处：《中华外科杂志》2007年第13期917-920,共4页Chinese Journal of Surgery

基　　金：国家自然科学基金(30371395)

摘　　要：目的探讨微环境诱导肝癌产生多药耐药的胞内信号传导途径。方法分别使HepG2细胞在缺氧、低糖环境下生长或稳定整合 HBX 基因,运用 Western 蛋白印迹法检测这些细胞内 ERK/MAPK 的活性。用 ERK/MAPK 特异性阻断剂 U0126处理这些细胞后,用 Western 蛋白印迹法检测缺氧诱导因子-1α(HIF-1α)和多药耐药相关蛋白的表达变化,逆转录聚合酶链反应和免疫细胞化学技术分别检测 HIF-1α在 mRNA 水平表达量和部位的改变。结果不同环境下生长的 HepG2细胞中,磷酸化/非磷酸化 ERK/MAPK 比例均有不同程度的增高。用 U0126处理12h 后,这些细胞中 HIF-1α和多药耐药相关蛋白的表达下降,且 HIF-1α表达由胞核向胞质转位,其 mRNA 水平无显著变化。结论 ERK/MAPK 信号通路是微环境诱导肝癌产生多药耐药的重要胞内信号传导途径。Objective To elucidate intracellular signal pathway in formation of multidrug resistance （MDR） of hepatocellular carcinoma （HCC） induced by its microenvironment,and to explore the potential role of extracellular signal-regulated kinase/mitogen-activated protein kinase （ERK/MAPK） pathway in this process. Methods Activity of ERK/MAPK was examined by Western blot technique through comparing the ratio of phosphorylation of ERK/MAPK to total ERK/MAPK protein in HepG2 cells exposed to hypoxia, low glucose or transfected by plasmid pcDNA3/HBX. After being treated by the specific ERK/MAPK pathway inhibitor U0126, Western blot technique was used to analyze the alterations of the expression of P-gp, MRP1, LRP and HIF-1 αat protein level. RT-PCR was used to analyze the alterations of the expression of HIF-1α mRNA. Cellular location of HIF-1α protein was determined by immunocytochemistry after being treated by U0126. Results The activations of ERK/MAPK determined by the ratio of phosphorylated ERK/ MAPK to the total ERK/MAPK were increased in varying degrees in HepG2 cells respectively exposed to different microenvironment. After being treated by U0126 for 12 h, the expressions of mdrl, MRP1, LRP genes and protein in those cells were decreased to some extent. However, the gene expression of HIF-1α was not influenced and only its protein was decreased. HIF-1α protein was reversely translocated into cytoplasm from nucleus after being treated by U0126. Conclusions ERK/MAPK pathway is involved in the course of the formation of MDR of HCC induced by microenvironment.

关 键 词：癌 肝细胞 抗药性 多药 细胞外调节激酶 缺氧诱导因子-1Α 

分 类 号：R735.7[医药卫生—肿瘤]