Department of Biomedical Sciences, Research Institute of Immunobiology, The Catholic University of Korea, Seoul 137-701, Republic of Korea.
Int J Mol Med. 2010 Jan;25(1):11-6.
Although Epstein-Barr virus (EBV) has been detected in 5-15% of gastric carcinoma (GC) cases, the mechanism by which EBV contributes to its tumorigenesis remains unclear. Only a subset of EBV latent proteins such as EBV nuclear antigen-1 and latent membrane protein 2A (LMP2A) are expressed in EBV-associated GC (EBVaGC) cases. In this study, to elucidate the role of LMP2A in the tumorigenesis of EBVaGC, we established permanent cell lines expressing LMP2A. The LMP2A gene was cloned from a naturally EBV-infected EBVaGC cell line, SNU-719 and transduced into an EBV-negative GC cell line, AGS, using a retroviral vector. The sequence of SNU-719 LMP2A showed several conserved variations compared to that of the prototype EBV strain B95-8 LMP2A. Four of seven established cell clones expressed LMP2A protein at detectable levels. These cell clones did not show enhanced cell growth compared to control cells in normal or low serum-containing medium. Furthermore, LMP2A expression had no effect on colony forming ability of the cell clones in soft agar. Our results suggest that LMP2A alone has little effect on tumorigenesis of EBVaGC.
虽然 Epstein-Barr 病毒（EBV）已在 5-15%的胃癌（GC）病例中被检测到，但 EBV 促进其肿瘤发生的机制尚不清楚。只有 EBV 潜伏蛋白的一部分，如 EBV 核抗原-1 和潜伏膜蛋白 2A（LMP2A），在 EBV 相关 GC（EBVaGC）病例中表达。在这项研究中，为了阐明 LMP2A 在 EBVaGC 肿瘤发生中的作用，我们建立了表达 LMP2A 的永久性细胞系。LMP2A 基因是从天然 EBV 感染的 EBVaGC 细胞系 SNU-719 中克隆出来的，并使用逆转录病毒载体转导到 EBV 阴性 GC 细胞系 AGS 中。与原型 EBV 株 B95-8 LMP2A 相比，SNU-719 LMP2A 的序列显示出几个保守的变异。在七个建立的细胞克隆中，有四个在可检测的水平上表达 LMP2A 蛋白。与对照细胞相比，这些细胞克隆在正常或低血清含量的培养基中没有显示出增强的细胞生长。此外，LMP2A 表达对细胞克隆在软琼脂中的集落形成能力没有影响。我们的结果表明，LMP2A 本身对 EBVaGC 的肿瘤发生影响不大。
