JAK3蛋白在鼻咽癌细胞中参与STAT活化并受EB病毒潜伏膜蛋白1调控

Expression of JAK3 in Nasopharyngeal Carcinoma Cell Line Associated With STAT Activation Regulated by EB Virus Encoded Protein LMP1

为了探讨在鼻咽癌细胞 (NPC)中是否存在EB病毒潜伏膜蛋白 1(LMP1) /JAK3/STAT信号传导途径 ,首先采用RT PCR方法对NPCJAK家族 4种成员检测 ,发现在两株鼻咽癌细胞株CNE1和HNE2中该家族 4种成员均有表达 .选择最有可能与LMP1相互作用的JAK家族成员JAK3作为我们的研究对象 .利用已建立的一株受四环素衍生物强力霉素 (doxycycline ,Dox)调控的LMP1表达的鼻咽癌细胞系 (Tet on LMP1HNE2 ) ,诱导Tet on LMP1HNE2细胞LMP1动态表达 ,蛋白质印迹发现JAK3的表达方式呈剂量和时间依赖性 .采用瞬间转染方法将STAT报告基因质粒 (GRR Luc)转染入pTet on LMP1HNE2细胞中 ,不同剂量的Dox促使LMP1的表达可以激活STAT报告基因活性 ,在 0 0 6mg/LDox诱导 36h时 ,STAT活性最高 .在该条件下 ,加入 3μmol/LJAK3特异性抑制剂WHI P131时 ,可抑制STAT的活性 .结果表明 :JAK3的表达在NPC细胞中受LMP1的调控 ,LMP1可以通过调控JAK3的表达参与STAT的活化 .

In order to investigate whether there exists LMP1/JAK3/ STAT signal pathway in NPC cell line, RT-PCR was first used to detect that four of JAK family members all expressed in two NPC cell lines CNE1 and HNE2. JAK3 which is the most possible associated with LMP1 was used to study further. A stable cell line Tet-on-LMP1 HNE2 expressing LMP1 regulated by tetracycline derivative Dox was used as a model. Western blotting was used to detect JAK3 expression in dose and time dependent fashion under dynamic changes of LMP1. STAT activity was observed after STAT reporter gene GRR-luc was transient transfected in Tet-on-LMP1 HNE2 cell and was induced by varied Dox dose for 36 h. At Dox concentration of 0.06 mg/L. STAT activity reached a peak. JAK3 specific inhibitor I WHI-PI31 can inhibit this peak STAT activity at concentration of 3 mumol/L. Therefore, JAK3 expressed in NPC cells can be regulated by LMP1 to activate STAT. The identified LMP1/JAK3/STAT signal pathway maybe plays an important role in NPC carcinogenesis.