EB病毒潜伏膜蛋白1多态性与鼻咽癌的关系

为了分析广东地区鼻咽癌病人和非鼻咽癌病人携带的Epstein-Barr病毒（EBV）潜伏膜蛋白1（LMP1）基因多态性，探讨LMP1基因羧基端缺失30个碱基的EBV是否与华南地区鼻咽癌高发有关。为此收集了初始的107例鼻咽癌病人和106例非鼻咽癌肿病人的漱口液，用巢式PCR扩增LMP1羧基端，观察缺失型LMP1的构成比。同时，测序分析缺失型LMP1编码区序列，了解缺失型LMP1多态性与鼻咽癌的关联度。结果：在50％的样品中可检出LMP1基因，缺失型LMP1在鼻咽癌病人和非鼻咽病人的构成比相似，约占70？％，原型和缺失型LMP1混合感染少见（0－6％）。另外，广州地区的缺失型LMP序列与上海、台湾、香港地区的缺失型LMP1基因高度同源，鼻咽癌病人是和非鼻咽癌病人携带的缺失型LMP1基因序列基本相同。此结果表明，广州地区流行的LMP1羧基端缺失30个碱基的EBV株，漱口液中检测出的缺失型与原型LMP1构成比约为7：3，在鼻咽癌病人和非鼻咽癌病人此分布情况相似。

The Relationship between Polymorphism of Latent Membrane Protein 1 of Epstein-Barr Virus and Nasopharyngeal Carcinomas in China

Epstein Barr virus(EBV)is involved in nasopharyngeal carcinomas(NPC),and a 30bp deletion variant of LMP1(del LMP1)is prevalent in NPC biopsies from southern China.This study tried to examine whether del LMP1 contributes to the prevalence of NPC in southern China.Throat washings (TWs) were collected from 106 cases of non NPC patients and 107 cases of NPC patients.Polymorphism of LMP1 was examined with nested PCR targeting C terminus flanking the 30bp deletion region.In addition,encoding regions of LMP1 were analyzed with direct sequencing.The results showed that LMP1 was detected in 50% of the TWs,del LMP1 was predominant in LMP1 positive TWs.Frequency of del LMP1 in NPC patients resembled that in non NPC patients,and mixed infection of prototype LMP1 and del LMP1 was infrequent.Furthermore,sequence analysis revealed that encoding region of del LMP1 derived from Guangzhou shared highly homology with that derived from Shanghai,Hongkong and Taiwan.The del LMP1 sequence derived from NPC patients was identical to that derived from non NPC patient in Guangzhou. So, del LMP1 was prevalent in Guangzhou area,similar constitution of LMP1 polymorphism was detected in NPC patients and non NPC patients.