Wnt/β-catenin信号因子在HepG2以及L02细胞中的表达  

Study on the role of Wnt/β-catenin signaling transduction pathway in hepatocellular carcinoma cell line HepG2 and L02 cell line

作　　者：王启明[1] 贾连群[2] 周鸿鹰[3] 李云生[1] 

机构地区：[1]天津医科大学解剖学教研室,天津300070 [2]辽宁中医药大学生化教研室,辽宁沈阳110032 [3]四川大学华西基础与法医学院解剖学教研室,四川成都610041

出　　处：《细胞与分子免疫学杂志》2007年第10期926-928,共3页Chinese Journal of Cellular and Molecular Immunology

基　　金：纽约中华医学基金会(CMB)基金资助项目(82-412);天津医科大学科研基金资助项目(2004XK34)

摘　　要：目的:比较Wnt/β-catenin信号分子在HepG2和L02细胞中的表达,探讨Wnt/β-catenin信号转导通路在肝癌发生中的作用机制,为肝癌的防治提供新的思路。方法:选取Wnt/β-catenin信号转导通路中上下游关键因子Wnt1、Wnt4、β-catenin、cyclin D1以及c-myc等,应用RT-PCR的方法观察他们在正常肝脏L02细胞和肝癌HepG2细胞中的转录水平。用免疫细胞化学染色方法和Western blot检测研究Wnt/β-catenin信号转导通路中最关键的成员β-catenin在上述2个细胞株中的定位和定量表达。结果:在正常的L02肝细胞中,用RT-PCR的方法未检测到Wnt1、Wnt4、cyclin D1以及c-myc的mRNA转录,只有β-catenin的基因被转录表达。同时用免疫细胞化学染色观察到β-catenin在L02细胞膜处存在表达。而在HepG2肿瘤细胞中,不仅检测到β-catenin的基因转录,同时也检测到Wnt1、cyclin D1以及c-myc的mRNA转录,只有Wnt4未转录。用免疫细胞化学的方法观察β-catenin在肿瘤细胞中的表达明显增强,表现为胞膜着色减弱而胞质甚至是胞核的阳性染色。采用Western blot检测也验证了β-catenin蛋白在肿瘤细胞中的表达水平明显高于正常细胞。结论:Wnt/β-catenin信号转导通路在人的肝癌细胞HepG2中存在异常活性,Wnt1可能是导致信号通路激活的始动因素之一。AIM： To explore the possible mechanism of action of Wnt/β-catenin signaling pathway in hepatocarcinogenesis by investigating the different expressions of the main members on this signaling pathway in hepatocellular carcinoma cell line HepG2 and L02 cell line. METHODS： The mRNAs of Wntl, Wnt4, β-catenin, cyclinD! and c-myc genes were amplified by means of semiquantitative reverse transcription polymerase chain reaction （RT-PCR） in normal liver cell line L02 and hepatocellular carcinoma cell line HepG2, respectively. At the same time, the proteins expression of β-catenin which was the key member in the Wnt/β-catenin signaling pathway was examined by immunocytochemical method and Westem blot technique. RESULTS： In normal liver cell line L02, the mRNAs of Wntl, Wnt4, cyclin DI and c-myc genes were not detected except for the gene of β-catenin. In hepatocellular carcinoma cell line HepG2, the mRNAs of Wntl, β-catenin, cyclin DI and c-myc genes were detected except for the gene of Wnt4. Meanwhile, found that β-catenin proteins were accumulated in the cytoplasm and/or nucleus in HepG2 but only in cell membrane in L02. Using Western blot technique, found that β-catenin proteins expression was higher in HepG2 than in L02. CONCLUSION： The Wnt/β-catenin signaling trans-duction pathway is activated with aberrant expression of Wnt! in hepatocellular carcinoma cell line HepG2.

关 键 词：WNT/Β-CATENIN 信号转导通路 肝癌 HEPG2 

分 类 号：R73-354[医药卫生—肿瘤]