GCG干预LMP1激活的NF-κB信号转导通路中的靶分子  

Interference of Epigallocatechin-3- gallate on Targets of Nuclear Factor κB Signal Transduction Pathway Activated by EB Virus Encoded Latent Membrane Protein 1*

作　　者：赵燕[1] 罗非君[1] 唐发清[1] 唐敏[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》2003年第1期122-128,共7页Progress In Biochemistry and Biophysics

基　　金：国家自然科学基金 ( 30 0 0 0 0 87);国家自然科学杰出青年基金资助项目 ( 395 2 5 0 2 2 ) .

摘　　要：为阐明在鼻咽癌 (nasopharyngealcarcinoma,NPC)细胞中茶多酚干预EB病毒潜伏膜蛋白 1(latentmembraneprotein 1,LMP1)激活的NF κB信号转导通路中的靶分子 ,采用EBV阴性及阳性的鼻咽癌细胞系CNE1和CNE1 LMP1细胞 ,利用噻唑蓝 (MTT)法 ,观察表没食子儿茶素没食子酸酯 (EGCG)对CNE1和CNE1 LMP1细胞生存率的影响 .采用瞬间转染及报道基因法观察EGCG对NF κB活性的作用 .利用间接免疫荧光法 ,观察EGCG对NF κB (p6 5 )核移位的影响 ,再分别提取CNE1和CNE1 LMP1的胞浆及胞核蛋白 ,通过蛋白质印迹分析EGCG抑制NF κB (p6 5 )的核移位后胞浆及胞核蛋白中NF κB (p6 5 )的变化 .采用蛋白质印迹分析EGCG对IκBα的磷酸化水平的影响 .采用瞬间转染及报道基因法观察EGCG对EGFR启动子活性的影响 ,并用蛋白质印迹分析EGCG对EGFR自身磷酸化的作用 .结果表明EGCG对鼻咽癌细胞的抑制作用有剂量依赖性 ,并可抑制NF κB的活性 .EGCG能抑制NF κB (p6 5 )的核移位 ,并抑制IκBα的磷酸化 .EGCG对NF κB信号通路下游的靶基因EGFR的启动子活性及自身磷酸化都有抑制作用 .由上述结果可以推断 ,EGCG对信号转导通路上的NF κB、NF κB (p6 5 )、IκBα、EGFR多个靶点分子具有干预作用 .LMP1是EB病毒编码的蛋白质 ,因此 。In order to elucidate the interference effect of epigallocatechin- 3- gallate on targets of nuclear factor κB signal transduction pathway activated by Epstein- Barr virus encoding latent membrane protein 1 in nasopharyngeal carcinoma (NPC) cells, the survival rate of CNE1 and CNE- LMP1 cells after EGCG treatment was determined by MTT assay. NF- κB activation in CNE1 and CNE- LMP1 cells after EGCG treatment was analyzed by promotor luciferase reporter system. And then nuclear translocation in NF- κB(p65)after EGCG treatment was analyzed by immunofluorescence and Western blotting. Meanwhile, the changes of IκBα phosphorylation were observed after EGCG treatment. EGFR promotor activity was analyzed by promotor luciferase reporter system and EGFR phosphorylation was observed by Western blotting after EGCG treatment. It was showed that EGCG inhibited the survival rate of CNE- LMP1 cells and NF- κB activation caused by LMP1 in CNE- LMP1 cells. EGCG also suppressed the nuclear translocation in NF- κB(p65)and IκBα phosphorylation. Meanwhile, EGCG inhibited EGFR promotor activity and EGFR phosphorylation. It can be concluded that EGCG can inhibit NF- κB ,NF- κB(p65),IκBα and EGFR which are key targets on NF- κB signal transduction pathway. It was suggested that interference effect of epigallocatechin- 3- gallate on signal transduction pathway which activated by LMP1 encoded by EB virus plays an important role in anticancer.

关 键 词：茶多酚 EGCG EB病毒 LMP) 激活 NF-ΚB信号转导通路 靶分子 潜伏膜蛋白1 鼻咽癌 干预 

分 类 号：R739.63[医药卫生—肿瘤]