Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok, Thailand.
Research and International Relations Division, HRH Princess Chulabhorn College of Medical Science, Bangkok, Thailand.
J Med Virol. 2019 Mar;91(3):444-449. doi: 10.1002/jmv.25318. Epub 2018 Oct 31.
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.
EB 病毒（EBV）是在胃组织中发现的传染性病原体之一。最近，EBV 相关胃癌（EBVaGC）被归类为胃癌的一种新亚型。迄今为止，人们对 EBV 在泰国人群中的正常胃和各种胃部病变（包括 EBVaGC）中的分布和流行情况知之甚少。在这项研究中，我们通过聚合酶链反应（PCR）扩增 EBV 的潜伏膜蛋白（LMP1）基因，检测了正常胃（NS；n=19）、慢性胃炎（CG；n=36）、肠上皮化生（IM；n=40）、胃发育不良（GD；n=15）和胃腺癌（GC；n=33）中的 EBV。EBV-PCR 扩增在 NS、CG、IM、GD 和 GC 中的阳性率分别为 42.1%、36.1%、22.5%、13.3%和 33.3%。为了进一步阐明 EBVaGC，我们对 GD 和 GC 中 EBV-PCR 阳性病例进行了 EBV 编码的小 RNA 原位杂交（EBER-ISH）。4 例 GC 病例为 EBER-ISH 阳性（12.1%），而 2 例 GD 病例均为 EBER-ISH 阴性。此外，我们根据 EBNA3C 序列确定 EBV 株（A型或 B 型）的分布，并根据 LMP1 变异（野生型和 30-bp 缺失变异；wt-LMP1 或 del-LMP1）确定 EBV 变体。结果表明，所有病变中最常见的是 A 型和 wt-LMP1。总之，EBV 在 NS 和胃部病变中都很常见，泰国患者中 EBVaGC 的发生率为 12.1%。
