Molecular Oncology and Viral Pathology Group, Portuguese Institute of Oncology of Porto, Porto, Portugal.
Department of Biology, University of Aveiro, Campus de Santiago, Aveiro, Portugal.
J Med Virol. 2015 Aug;87(8):1382-8. doi: 10.1002/jmv.24190. Epub 2015 Apr 16.
Variations in the genome sequence of Epstein-Barr Virus (EBV) are thought to lead to differential interaction with host cells, immune evasion, and transformation. The discussion regarding EBV strains as having a geographic or disease-association has been increasing and the majority of studies are performed in Asiatic populations. We developed a case-control study with 139 individuals, including 96 subjects with different malignancies and 43 healthy individuals, from the North region of Portugal. We have used PCR protocols for the characterization of EBV strains (type A or B) based on EBNA3C genome variation and for the LMP1 30bp-deletion variants (wt-LMP1 or del-LMP1). Our study showed that type A is the most prevalent in our population (100% of healthy controls, 96.9% of aHSCT patients, 90.8% of HNSCC patients, and 94.9% of NPC patients) and that type B was significantly associated with NPC (P = 0.019; RR = 8.90). Regarding the LMP1 30bp-deletion, we found a similar distribution of both wt- and del-LMP1 variants in controls and dispare results in cases: del-LMP1 was more frequent in aHSCT and HNSCC patients (64.7% and 63.2%, respectively) and wt-LMP1 in NPC patients (100%). In fact, the study reveals that wt-LPM1 was significantly associated with NPC (P < 0.001; RR = 18.4). Hence, our study showed that EBV type B and wt-LMP1 variant seem to be associated with NPC in our population, with a clear disease-association for wt-LMP1. These results contribute for the knowledge of EBV genetic diversity among Caucasian populations.
EBV 病毒（EBV）基因组序列的变异被认为导致与宿主细胞的不同相互作用、免疫逃逸和转化。关于 EBV 株具有地理或疾病相关性的讨论一直在增加，并且大多数研究都是在亚洲人群中进行的。我们进行了一项病例对照研究，共有 139 人参与，包括 96 名患有不同恶性肿瘤的患者和 43 名健康个体，他们来自葡萄牙北部地区。我们使用了基于 EBNA3C 基因组变异的 EBV 株（A型或 B 型）特征的 PCR 方案，以及 LMP1 30bp 缺失变体（wt-LMP1 或 del-LMP1）。我们的研究表明，A型在我们的人群中最为普遍（100%的健康对照者、96.9%的异基因造血干细胞移植患者、90.8%的头颈部鳞状细胞癌患者和 94.9%的鼻咽癌患者），而 B 型与鼻咽癌显著相关（P=0.019；RR=8.90）。关于 LMP1 30bp 缺失，我们发现对照组中 wt-LMP1 和 del-LMP1 变体的分布相似，但病例组的结果却不同：del-LMP1 在异基因造血干细胞移植和头颈部鳞状细胞癌患者中更为常见（分别为 64.7%和 63.2%），wt-LMP1 在鼻咽癌患者中更为常见（100%）。事实上，这项研究表明 wt-LPM1 与鼻咽癌显著相关（P<0.001；RR=18.4）。因此，我们的研究表明 EBV B 型和 wt-LMP1 变体似乎与我们人群中的鼻咽癌有关，wt-LMP1 与疾病的相关性更为明确。这些结果为了解高加索人群中 EBV 的遗传多样性做出了贡献。
