EB病毒潜伏膜蛋白1在鼻咽癌细胞中通过STAT3促进VEGF表达  

Regulation of Human VEGF by Expression Latent Membrane Protein 1 Encoded by EB Virus Via STAT3 in Nasopharyngeal Carcinoma Cell Line

作　　者：谭运年[1] 陶永光[1] 李力力[1] 刘素芳[1] 唐敏[1] 顾焕华[1] 曹亚[1] 

机构地区：[1]中南大学湘雅医学院肿瘤研究所,长沙410078

出　　处：《生物化学与生物物理进展》2004年第5期427-431,共5页Progress In Biochemistry and Biophysics

基　　金：国家重点基础研究发展规划 ( 973 )"恶性肿瘤发生发展的基础研究"项目 (G19980 5 12 0 1);国家自然科学基金 ( 3 0 0 0 0 0 87和3 0 10 0 0 0 5 );国家自然科学基金杰出青年基金 ( 3 95 2 5 0 2 2 )资助项目~~

摘　　要：探讨了EB病毒编码的潜伏膜蛋白 1(LMP1)是否通过STAT3调控诱导血管内皮细胞生长因子 (VEGF)的表达 .利用蛋白质印迹的方法对HNE2、HNE2 LMP1以及瞬时转染STAT3显性负性突变体STAT3β的HNE2 LMP1细胞中VEGF含量进行检测 ,发现LMP1可以上调VEGF的表达 ,而STAT3β可以抑制VEGF的上调 ;利用LMP1可控表达细胞系tet on LMP1 HNE2进行LMP1时间和剂量诱导表达研究 ,发现VEGF可以随LMP1的动态表达而表达 ;将VEGF野生型报告基因和VEGF潜在的STAT3转录因子突变体报告基因与LMP1表达载体分别共转染研究发现 ,LMP1可以激活VEGF的转录 ,这种转录通过VEGF启动子区STAT3转录因子的结合位点发挥作用 ;电泳迁移率变动分析 (EMSA)确证了STAT3的这种DNA位点的特异性活性 .结果表明 :EB病毒编码的LMP1在鼻咽癌细胞中可以增加VEGF的转录和表达 。In order to identify whether EB virus latent membrane protein I ( LMP1) can regulate vascular epithelial growth factor ( VEGF) expression via STAT3 in nasopharyngeal carcinoma cell line, Western blotting was used to detect VEGF expression in HNE2, HNE2-LMP1 and HNE2-LMP1 transient transfected with STAT3 dominant negative plasmid STAT3P. VEGF is up-regulated by LMP1 and STAT3 dominant negative STAT3P can down-regulate VEGF expression. In tet-on-HNE2-LMP1 cell line, in which LMP1 can be tightly regulated, VEGF is expressed in dose and time dependent fashion. After cotransfected LMP1 with VEGF wild promoter luciferase reporter and 848 mutated luciferase reporter respectively, luciferase assay results indicated that LMP1 can upregulate wild promoter luciferase activity and not that of 848 mutated luciferase reporter. Electrophoretic mobility shift assay results in HNE2 and HNE2-LMPI cell line indicated that LMP1 enhances STAT3 binding ability in VEGF promoter. In conclusion, latent membrane protein I encoded by EB virus can enhance VEGF transcription and expression in nasopharyngeal carcinoma cell line via activating STAT3 binding ability in VEGF 848 promoter binding site.

关 键 词：EB病毒 潜伏膜蛋白1(LMP1) STAT3 血管内皮细胞生长因子(VEGF) 鼻咽癌 

分 类 号：R734[医药卫生—肿瘤]