EBV潜伏基因产物在恶性淋巴瘤组织中的表达及意义

目的：探讨EBV潜伏基因产物在恶性淋巴瘤组织中的表达及意义。方法：用免疫组化方法对565例NHL、64例HL人体标本进行LMP－1、EBNA2对比检测并选择101例NHL进行PCR检测。结果：EBV－PCR检出率（19．8％）高于LMP－1（14．9％）,PCR阴性病例LMP－1全部为阴性,EBNA2在全部病例均为阴性,在NHL,LMP－1阳性细胞主要是免疫母细胞样细胞、R－S样细胞和R－S细胞,LMP－1阳性的R－S样细胞我数表达活化分子CD30。肠道原发恶性淋巴瘤EBV检出率较高（23．1％）。T淋巴瘤EBV检出率（23．8％）高于B淋瘤（10．2％）。结论：EBV潜伏基因产物表达情况能够反映出宿主细胞的分化程度和（或）宿主的免疫监视作用。EVB在R－S样细胞形成可能起作用。EBV感染与肠道恶性淋巴瘤的发病有关。     

儿童淋巴瘤患者EBV-LMP1基因C末端30bp缺失突变检测

目的 研究儿童淋巴瘤来源的EBV-LMP1基因C末端30 bp缺失突变情况并分析其意义.方法 应用巢式聚合酶链反应技术(Nested-PCR)扩增免疫组化检测EBV-LMP1或原位杂交检测EBV.EBERS阳性的霍奇金淋巴瘤、非霍奇金淋巴瘤和淋巴结反应性增生病理标本中EBV-LMP1基因,并进行序列分析.结果 EBV-LMP1羧基端30 bp缺失的del-LMP1的检出率在霍奇金淋巴瘤、非霍奇金淋巴瘤和淋巴结反应性增生分别为11/25、3/8和5/15,三组间差异无统计学意义(P=0.793,X2=0.463).经序列分析发现,所扩增的EBV-LmP1基因型可分为三个亚型:B95.8、China1和China2.结论 EBV羧基端30 bp缺失的del-LMP1基因型广泛存在EBV阳性的儿童霍奇金淋巴瘤、非霍奇金淋巴瘤和淋巴结反应性增生病例中,与疾病本身没有关系.儿童来源的EBV-LMP1基因型主要可分为B95.8、China1和China2三个亚型.     

CD21非依赖性EB病毒对人胃印戒细胞癌细胞系的感染

目的　探讨CD2 1非依赖性EB病毒 (EBV)对人胃印戒细胞癌细胞系 (HSC 39)的感染作用。方法　用Akata和P3HR 1EBV毒株感染HSC 39,有限稀释法对感染细胞进行克隆。结果　两种EBV毒株感染细胞中均可检测到EBV编码的小RNA(EBER)的表达 ,两种EBV毒株感染的亲代细胞及大多数细胞克隆表达EBV核抗原 (EBNA1) ,但不表达EBNA2、潜伏期膜蛋白 (LMP1)和LMP2A。表现为潜伏Ⅰ型感染。未感染的HSC 39细胞及P3HR 1感染的细胞克隆CD2 1表达阴性 ,而AkataEBV感染的部分细胞克隆CD2 1mRNA阳性。结论　EBV可能通过不依赖CD2 1受体的途径感染HSC 39,印戒细胞癌细胞系可用作EBV感染的靶细胞。     

鼻咽癌中EB病毒LMP1基因的序列变异

目的 检测广州地区鼻咽癌中EB病毒LMP1基因N-和C-末端区序列变异的热点,并探讨其产生的机制。方法 收集中山大学肿瘤医院未经治疗的鼻咽癌患者鼻咽新鲜活检标本63例。采用巢式聚合酶链反应（PCR）扩增EB病毒LMP1基因N-和C-末端区,用XhoⅠ对N-末端区扩增产物进行酶切分析,并检测C-末端区扩增产物30bp缺失的情况。采用四色荧光末端终止法对4例患者N-和C-末端区的8份扩增产物进行序列分析。结果 63例鼻咽癌组织EB病毒LMP1基因N-和C-末端区有4种序列变异类型：wt-XhoⅠ／wt-LMP1（4例,6．3％）、wt-XhoⅠ＆XhoⅠ-loss／del-LMP1（4例,6．3％）、wt-XhoⅠ／del-LMP1（5例,7．9％）和XhoⅠ-loss／del-LMP1（50例,79．5％）。序列分析显示：与B95-8细胞相比较,所有检测的鼻咽癌组织中EB病毒LMP1基因均发生了错义点突变和无义点突变。错义点突变数与无义点突变数之间的比值为2．25（9／4）。结论 广州地区鼻咽癌中EB病毒LMP1基因的序列变异类型以XhoⅠ-loss／del-LMP1占主导。LMP1基因N-末端区XhoⅠ酶切位点的丢失很可能是在C-末端区30bp缺失的基础上发生的。LMP1基因的4种序列变异类型可能代表了鼻咽癌变过程中EB病毒在宿主内演变的4个时相。     

鼻咽癌组织中EB病毒潜伏相关基因的表达

目的： 通过检测鼻咽癌组织中EB病毒的潜伏膜蛋白LMP1的序列以及LMP1、EBNA1、EBNA2的mRNA表达来探讨EB病毒的感染状态及其表达产物与鼻咽癌的关系。方法: 应用PCR法检测鼻咽癌组织中LMP1 DNA的存在，并对鼻咽癌来源的LMP1和EB病毒永生化狨猴B淋巴细胞系B95-8来源的LMP1进行测序，比较序列的差异。利用巢式RT-PCR检测鼻咽癌组织中LMP1、EBNA1、EBNA2的mRNA表达。结果: 47例鼻咽癌组织均含有LMP1 DNA，所有鼻咽癌来源的LMP1 DNA与B95-8来源的LMP1 DNA序列比较均存在着多个单核苷酸变异，最明显的是XhoⅠ酶切位点的丢失。测序后显示鼻咽癌来源的LMP1 DNA有30个核苷酸的丢失。巢式RT-PCR显示LMP1、EBNA1、EBNA2在鼻咽癌中的mRNA表达率分别为76.6％、80.0％和74.5％。其中EBNA1的表达是由Qp启动的，而B95-8细胞中EBNA1的表达是由Cp启动的。结论: 鼻咽癌中EB病毒的作用途径比较复杂，LMP1、EBNA1、EBNA2等潜伏期基因还有早期裂解基因BARF1均可能参与鼻咽癌的发生发展过程。     

EBV潜伏膜蛋白LMP2A的研究进展

EB病毒（Epstein-Barr virus,EBV）与多种人类恶性肿瘤如Burkitt淋巴瘤、鼻咽癌（na-sopharyngeal carcinoma,NPC）、何杰金氏病（Hodgkin＇s disease,HD）等的发生有关,肿瘤组织中EBV主要以潜伏感染的形式存在。在EBV潜伏感染细胞中,可表达的EBV基因有10多种,包括EBV核抗原（EB nuclear antigen,EBNA）1,2,3A,3B,3C和LP;潜伏膜蛋白（latent membrane protein,LMP）1,2A和2B;EBV编码的小RNA（EBER）1和2;以及BamHⅠ-A向右开放读码框（BARF0）的转录产物。NPC和其他EBV相关恶性肿瘤中可持续检测到LMP2A的转录物,提示LMP2A在体内病毒持续感染和EBV相关疾病中可能有重要作用。     

涎腺淋巴上皮癌中EB病毒潜伏膜抗原-1基因30碱基缺失的研究

目的 了解潜伏膜抗原(LMP)-1基因3’端DNA的30碱基在涎腺淋巴上皮癌中的缺失率及LMP-1的基因亚型。方法 用聚合酶链反应(PCR)方法对46例涎腺淋巴上皮癌中EBV编码LMP-1基因3’端DNA进行扩增,观察有无30碱基(bp)缺失。为减少从石蜡组织中提取DNA失败产生的影响,同时对样本作B-肌动蛋白基因扩增,并对PCR产物进行测序。结果 46例标本中4例经β-肌动蛋白基因扩增证实为DNA提取失败。剩余42例样本中35例(83．3％)检出LMP-1 DNA。阳性样本PCR产物电泳条带位置有2种,分别位于300bp上下,其中高于300bp有31例(88．6％),低于300bp有4例(11．4％)。DNA测序证实二者碱基相差30bp,分别为316bp和286bp。结论 涎腺淋巴上皮癌中存在EBV编码LMP-1基因3’端DNA的30bp缺失,但大多数为非缺失型LMP-1。     

重庆地区急性呼吸道感染患儿呼吸道合胞病毒流行特征及其G基因序列分析

目的 分析重庆地区2008-2009年度急性呼吸道感染住院患儿呼吸道合胞病毒(respiratory syncytial virus,RSV)的亚型流行情况,并了解优势流行株BA株的G蛋白基因特征.方法 采集2008年4月-2009年3月全年于重庆医科大学附属儿童医院因急性呼吸道感染住院的508例患儿鼻咽深部分泌物,用RT-PCR方法检测RSV并进行亚型鉴定,选取29例B亚型和10例A亚型RSV阳性标本,用RT-PCR的方法扩增全长G蛋白并测序.结果 在508例标本中,RSV阳性126例(24.8%),其中检测出A亚型43例(34.1%),B亚型80例(63.5%),A、B亚型混合感染3例(2.4%).所测的10株A亚型的G基因与标准株A2的核苷酸同源性为91.4%～92.0%,均属GA2基因型;29株B亚型的G基因与标准株CH18537的核苷酸同源性为92.0%～93.0%,其中19株均为具有60个高度重复核苷酸插入的BA株.B亚型流行株与CH18537标准株相比,G基因有多种核苷酸变异如缺失、插入等,尤其在G蛋白近C端1/3处的高变区.结论 2008-2009年RSV仍是重庆地区儿童急性呼吸道感染的主要病原,与既往两年A亚型优势流行不同,2008-2009年度B亚型毒株流行占优;近年新发现的BA株可能已成为本地区优势流行株,BA株G基因变异是否导致G蛋白功能增强,进而促进其优势流行尚有待研究.     

EBV LMP1和CMVpp65在肾脏疾病肾组织中的表达

目的 研究非洲淋巴细胞瘤病毒LMP1(EBV LMP1)、巨细胞病毒pp65(CMVpp65)在肾脏疾病患者肾组织中的表达情况,探讨病毒感染与人类肾脏疾病发生、发展的关系.方法 临床资料齐全的肾穿刺活检标本435例,免疫组化法检测EBV LMP1和CMVpp65在肾组织中的表达情况.结果 (1)175例(40.2%)肾组织中EBV LMP1表达阳性,狼疮性肾炎(LN)组及IgA肾病(IgAN)组与非免疫性肾病组及原发性肾炎(PGN)组比较,差异有统计学意义;170例(39.1%)肾组织中CMVpp65表达阳性,LN组与非免疫性肾病组及PGN组比较,差异有统计学意义;(2)PGN组初发患者与复发患者肾组织EBV LMP1、CMVpp65阳性率比较差异有统计学意义,其他病种则无;(3)合并感染与无合并感染患者EBV LMP1、CMVpp65阳性率比较差异均无统计学意义;(4)肾组织EBV LMP1表达阳性的LN患者血清anti-Sm-Ab阳性率高于阴性组(P<0.05,OR=6.00,95%CI:1.200～29.998);而CMVpp65表达阳性者血清anti-Sm-Ab阳性率低于阴性组(P<0.01,OR=0.156,95%CI:0.038～0.643).结论 肾组织EBV及CMV感染可能参与LN及IgAN的发病,其中EBV感染可能以分子拟态方式诱发系统性红斑狼疮.     

肺癌患者EBV感染、LMP1和Bcl-2表达状况的研究

目的 研究肺癌患者癌组织中EB病毒（Epstein-Barr virus,EBV）感染、EBV潜伏膜蛋白1 （latent membrane protein 1,LMP1）和B淋巴细胞瘤/白血病-2基因（B cell lymphoma/Leukemia-2,Bcl-2）的表达及意义。方法 采用原位杂交法（in situ hybridization,ISH）检测肺癌组织标本中EBV编码的小RNA（ EBER1）,免疫组化法（immunohistochemistry,IHC）检测Bcl-2和LMP1的表达,以GD-6多媒体彩色病理图像分析系统进行形态学定量,以图像的平均面积（average area,AA）和积分吸光度（Integral optical density,IA）表示表达量的多少。结果 在108例肺癌癌组织中36例EBV阳性,阳性率为33.3％;LMP1阳性表达7例,阳性率6.5％。EBV阳性肺癌组中Bcl-2表达显著高于EBV阴性组,其AA分别为58014.23±6918.45和38156.22±4096.79,其IA分别为11.00±1.48和8.03±0.78,差异有统计学意义。进一步分析LMPI和Bcl-2表达的关系,可见LMP1可使Bcl-2表达率增加,但定性分析和定量分析差异无统计学意义。结论 EBV感染使Bcl-2表达增加,可能在肺癌的发生发展中有一定作用。在肺癌组织中EBV可能不是通过LMP1来影响Bcl-2的表达,具体机制有待进一步研究。     

Epstein-Barr virus infection and its gene expression in gastric lymphoma of mucosa-associated lymphoid tissue

The role of Epstein-Barr virus (EBV) in the pathogenesis of gastric lymphoma of mucosa-associated lymphoid tissue (MALT) has not been well understood. The aim of the study was to investigate EBV infection and its gene expression in this tumor in order to understand its role in the pathogenesis. EBV infection was screened by in situ hybridization for EBV-encoded nonpolyadenylated RNA (EBER ISH) in 79 cases of gastric MALT lymphoma of nonimmunocompromised patients. The expression of EBV proteins [LMP1 (latent membrane protein 1), EBNA2 (EBV nuclear antigen 2), ZEBRA (switch protein encoded by BZLF1 gene)] was studied by immunohistochemistry in EBER-positive cases. EBV was detected with EBER ISH in 15 (19%) of the 79 cases. EBV was found in virtually all tumor cells in 2 cases of high-grade MALT lymphoma (2.5%) (EBV-associated), and was found only in occasional large or small lymphoid cells in 13 cases (16.5%). False positive EBER signal was detected in the mucinous glandular epithelial cells of gastric antrum with FITC-labeled oligonucleotide probe but not with digoxigenin or ³⁵S-labeled riboprobes. Type II latency (EBER+LMP1+ EBNA2-) was detected in both EBV-associated cases. Type III latency (EBER+LMP1+EBNA2+) was also identified in one EBV-associated case besides latency II. Double labeling showed coexpression of LMP1 and EBNA2 in a small number of tumor cells, indicating the presence of type III latency in single cell level. In cases with only occasional EBER-positive large or small lymphoid cells, LMP1 and EBNA2 were not detected. ZEBRA was negative in all the cases. These findings suggest that EBV may contribute to the pathogenesis of a small proportion of high-grade MALT lymphoma, where virtually all tumor cells harbored EBV and the oncogenic viral protein LMP1 was expressed. Moreover, latency III of EBV infection may exist in nonimmunocompromised patient. J. Med. Virol. 56:342–350, 1998 . © 1998 Wiley-Liss, Inc.     

Distribution of the Epstein-Barr virus in the normal stomach and gastric lesions in Thai population

The Epstein-Barr virus (EBV) is one of the infectious agents found in stomach tissue. Recently, EBV-associated gastric carcinoma (EBVaGC) was classified as a new subtype of gastric carcinoma. To date, there is a lack of knowledge about the distribution and prevalence of EBV infection in both the normal stomach and various gastric lesions, including EBVaGC, in the Thai population. In this study, we detected EBV in the normal stomach (NS; n = 19), chronic gastritis (CG; n = 36), intestinal metaplasia (IM; n = 40), gastric dysplasia (GD; n = 15), and gastric adenocarcinoma (GC; n = 33) by polymerase chain reaction (PCR) amplification of the latent membrane protein (LMP1) gene of EBV. EBV-PCR amplification was positive in 42.1%, 36.1%, 22.5%, 13.3%, and 33.3% of NS, CG, IM, GD, and GC, respectively. For further clarification in EBVaGC, we performed EBV-encoded small RNA in situ hybridization (EBER-ISH) in PCR-positive cases of GD and GC. Four GC cases were EBER-ISH positive (12.1%), while both GD cases were EBER-ISH negative. In addition, we determined the distribution of the EBV strain (type A or B) based on EBNA3C sequence and EBV variants based on LMP1 variation (wild-type and 30-bp deletion variants; wt-LMP1 or del-LMP1). The results showed that type A and wt-LMP1 were the most prevalent in all lesions. In conclusion, EBV is common in both the NS and gastric lesions, and the frequency of EBVaGC was 12.1% in Thai patients.     

Epstein-Barr virus genetic variation in Vietnamese patients with nasopharyngeal carcinoma: full-length analysis of LMP1

Genetic variation in tumor virus genes and its impact on function might contribute to the understanding of geographic differences in risks for virus-associated tumors. This is particularly true for the genes known to contribute to the biology of the tumor. It is has been proposed that Epstein-Barr virus (EBV) gene variation has a role in the high risk of nasopharyngeal carcinoma (NPC) in South-East Asia. NPC is among the five most common cancers in Vietnam. EBV-NPC cells always express EBV nuclear antigen 1 (EBNA1) and also frequently latent membrane protein 1 and 2 (LMP1 & LMP2). To investigate EBV gene variation in Vietnamese NPC patients we analyzed the full length of LMP1 gene including its promoter region, and the N-termini of both EBNA1 and LMP2A genes from five NPC biopsies. We detected two EBV variants V1 and V2 based on the LMP1 nucleotide sequence pattern compared with the prototype B95-8 and some available sequences including Chinese variants. The V1 variant shows strong similarity to a variant dominant in Southern China (China 1), while the V2 variant is similar to a Thai variant SEA 2 and partly identity with GD1 in the C-terminus. The promoter region and transmembrane domain of the SEA 2-like samples contained some specific differences compared with previously published variants. In contrast, analysis of EBNA1 N- and LMP2A N-termini only revealed minor changes. Our findings reinforces that the polymorphisms of whole LMP1 sequence should be considered in future EBV molecular epidemiology studies in different geographic populations.     

Association of distinctive Epstein–Barr virus variants with gastric carcinoma in Guangzhou,southern China

To investigate the clinicopathologic features, Epstein–Barr virus (EBV) latency pattern and genome polymorphism of EBV‐associated gastric carcinoma (EBVaGC) in Guangzhou, an endemic area of nasopharyngeal carcinoma (NPC), an in situ hybridization assay of EBV‐encoded small RNA‐1 (EBER‐1) was used to identify the presence of EBV in 676 consecutive gastric carcinoma cases. EBV‐encoded proteins EBNA1, EBNA2, LMP1, and ZEBRA were detected by immunohistochemistry. EBV genome polymorphism was also analyzed by PCR and DNA sequencing. Of the 676 cases, 45 EBV‐positive cases (6.7%) were identified, including 37 (8.5%) male and 8 (3.3%) female cases. EBNA1 was detected in 42 cases (93.3%), while EBNA2, LMP1, and ZEBRA were all negative. In the EBV genome polymorphism analysis, type A strain, prototype F, type I, XhoI?, and del‐LMP1 variants were predominant among EBVaGC patients, accounting for 44 (97.8%), 37 (82.2%), 45 (100%), 34 (75.6%), and 42 (93.3%) cases, respectively. Moreover, a new hotspot mutation in the BamHI‐W1/I1 boundary region (148,972 T → C) was found in 39 (86.7%) of the 45 cases. The predominant EBV variants in EBVaGC in Guangzhou are prototype F, type I, and XhoI?, which are different from those in NPC in this area (predominant variant‐type “f”) and in EBVaGC in Latin American countries (predominant type “i” and XhoI+), suggesting that the EBV variants are not only geographically distributed but also disease restricted, and the pathogenic role of EBV in different EBV associated epithelial malignancies in different areas may be distinct. J. Med. Virol. 82:658–667, 2010. © 2010 Wiley‐Liss, Inc.     

Epstein-Barr virus latent and replicative gene expression in oral hairy leukoplakia

Oral hairy leukoplakia is an epithelial lesion of the tongue associated with productive infection by Epstein-Barr virus (EBV). However, no data concerning the pattern of EBV latent gene expression have been reported, and it remains unresolved whether true latent infection occurs in basal cell layers of oral hairy leukoplakia. We have studied six cases of oral hairy leukoplakia using monoclonal antibody immunohistology for EBV latent--EB nuclear antigen (EBNA) 1, EBNA 2 and latent membrane protein 1 (LMP 1); immediate-early (BZLF1); and replicative (EA, VCA, MA) proteins, and for the EBV-receptor (CD21 antigen). EBV DNA was demonstrated by nucleic acid in situ hybridization. Mid- to upper-zone keratinocytes contained EBV DNA and co-expressed EBNA 1, EBNA 2 (5 of 6 cases), LMP 1, BZLF1 protein, EA, VCA and MA. No EBV genome or gene expression could be demonstrated in basal or parabasal cells. Spinous keratinocytes were labelled by anti-CD21 antibodies HB5 and B2, but did not express the EBV-receptor as defined by reactivity with OKB7. The co-expression of latent and replicative infection-associated antigens is striking, indicating possible functional roles for latent proteins during the productive cycle. Our results suggest that oral hairy leukoplakia is caused by repeated direct infection of upper epithelial cells with virus from saliva or adjacent replicatively infected cells, rather than by a latent EBV infection of basal epithelial cells with a differentiation-dependent switch to productive infection as previously proposed.     

Structural variability of the carboxy-terminus of Epstein-Barr virus encoded latent membrane protein 1 gene in Hodgkin's lymphomas

Epstein-Barr virus (EBV) is implicated in the pathogenesis of several lymphoid and epithelial neoplasms. Latent membrane protein 1 (LMP1) is the major viral oncogene and it is controversial whether tumor LMP1 variants reflect their geographical predominance or are associated with enhanced oncogenic properties. This study aimed to analyze LMP1 molecular variability of 62 EBV+ Hodgkin's lymphomas and 22 non-neoplastic controls from Brazil and Argentina. EBV association was characterized by EBER-ISH, LMP1 immunohistochemistry and PCR assays for EBNA2 and 3C (typing), LMP1 30 bp deletion (del30) and number of 33 bp tandem repeats. LMP1 C-terminal sequencing was performed in 42 cases. EBV1 was the predominant strain in both geographical Hodgkin's lymphoma groups (average 82%). A higher frequency of del30 variant was observed in lymphomas (41/63) than in non-neoplastic controls (6/22) (OR 4.97, CI 95% 1.53-16.79; P = 0.005, chi(2) test). A large number (5-7) of 33 bp repeat units was characteristic of del30 LMP1 variants (P < 0.0001, Fisher's exact test). Sequence analysis showed a similar mutation spectrum to that described worldwide but none of the current classification schemes could be applied completely. A distinct structural pattern was observed in del30 variants, characterized by a large number of 33 bp repeat units and the presence of a 15 bp insertion encoding the JAK3 Box-1a motif (3/15 wt vs. 16/20 del30; P = 0.001, chi(2) test). The results suggest a pathogenic role for LMP1 del30 variants in Hodgkin's lymphoma from South America and point to particular virus-host molecular mechanisms, such as genomic instability in LMP1 carboxy-terminus, leading to enhanced production and selection of these deletion variants.     

鼻咽癌中EB病毒BamHI"f"变异和潜伏膜蛋白1基因XhoI缺失型的分析

目的 检测鼻咽癌组织中EB病毒BamHI“f”和LMP1。XhoI—loss基因变异并探讨其意义。方法 采用聚合酶链反应(PCR)、巢式PCR和限制性酶切分析检测40例鼻咽癌组织中EB病毒BamHI“f”和LMP1 XhoI—loss基因变异。对48例健康成人外周血单个核细胞进行了EB病毒LMP1 XhoI—loss变异的检测。对3例具有代表性的PCR产物进行了基因序列分析。结果 40例鼻咽癌中EB病毒BamHI“f”变异型30例(75％),BamHI F型10例(25%)。40例鼻咽癌组织中39例同时进行了EB病毒LMP1 XhoI—loss的检测,30例(76．9%)为LMP1 XhoI—loss;7例(18．0％)为LMP1 Wt—XhoI;2例为LMP1 Wt-XhoI和XhoI-loss并存。97．4％(38／39)鼻咽癌中至少出现一种类型：EB病毒基因变异。仅1例鼻咽癌为EB病毒LMP1 Wt—XhoI／BamHI F,基因序列分析(LMP1第3外显子)发现也有7个碱基替换(其中5个为错义突变和2个为同义突变)。48例健康成人外周血单个核细胞有10例(20．8%,10／48)成功扩增出EB病毒LMP1片段,10例均为LMP1 Wf—XhoI。结论 与B95—8细胞株中EB病毒基因比较,鼻咽癌组织中EB病毒几乎均存在基因变异。健康成人携带的均为EB病毒LMP1 Wt—XhoI,而鼻咽癌细胞中主要为LMP1 XhoI—loss。因而,EB病毒基因变异可能与鼻咽癌的发生发展过程有关。     

LMP1 gene polymorphism in patients with Epstein-Barr virus-negative gastric carcinomas in Russia

The investigation was undertaken to study the molecular characteristics of Epstein-Barr virus (EBV) LMP1 gene samples amplified from the tumor and intact tissues of patients with EBV-negative forms of gastric carcinoma (GC). The genetic structure of these samples determined by their sequencing was compared with that of the gene samples isolated from the cells of oropharyngeal washing specimens from the same patients with GC, as well as peripheral blood lymphocytes of patients with infectious mononucleosis (IM) and blood donors. The findings suggest that the samples of tumor tissue LMP1 from patients with GC have higher divergence than those from patients with IM and blood donors although no specific variants of the gene for GC were found. Comparison of LMP1 sequences from tumor tissue and cells of oropharyngeal washing specimens from the same patients with EBV-negative GC revealed the common LMP1 variant in 2 cases while they differed in 3 cases. The findings are an initial step in studying the role of EBV in the carcinogenesis of EBV-negative GC that is likely to be established by investigations on representative clinical material, by applying the up-to-date technologies.     

Epstein-Barr virus gene expression and latent membrane protein 1 gene polymorphism in pediatric liver transplant recipients

Immunosuppressed pediatric transplant recipients are at risk of developing Epstein–Barr virus (EBV)‐associated complications (such as post‐transplant lymphoproliferative disorders). Monitoring of the EBV DNA level in blood alone has a low predictive value for the post‐transplant course of EBV infection and its complications. Therefore, additional prognostic markers are widely sought. The study aim was to analyze EBV gene expression patterns and LMP1 polymorphism in relation to EBV DNA levels in pediatric liver transplant recipients. EBV load measurement, LMP1 variant, and gene expression analysis were performed in collected prospectively multiple blood samples from 30 patients. Several distinct patterns of EBV gene expression were identified: latency 2 (71%), latency 3 (13%), latency 0 (11%), and lytic infection (5%). In most children's multiple blood samples, both EBV gene expression patterns and expression levels of individual EBV genes varied significantly over time. EBV gene expression patterns were not associated with the EBV load. However, the viral load correlated with the LMP1 and LMP2 expression (r = 0.34; P = 0.006, and r = 0.45; P = 0.001, respectively). Two variants of the LMP1 gene were detected, and they were consistent over time in individual patients. A wild type of LMP1 was associated with higher EBV‐DNA loads (P = 0.03). This indicates that EBV infection in immunosuppressed patients is a very dynamic process, but changes in the state of EBV infection do not influence significantly the viral load. The latter, however, can be associated with the activity of LMP1 and LMP2 genes, as well as polymorphism of LMP1. J. Med. Virol. 83:2182–2190, 2011. © 2011 Wiley Periodicals, Inc.