Prevalence and characteristics of Epstein-Barr virus associated gastric carcinoma in Gansu Province, Northwest China with mRNA expression of glycoprotein BMRF2.

Abstract

Gansu province is a region with the highest gastric cancer incidence and mortality in Northwest China. Epstein-Barr virus-associated gastric carcinoma (EBVaGC) is an important subtype of gastric cancer which shows specific clinicopathological features such as older-age bias, male predominance, lower lymph-node-metastasis, and a better cancer-related survival comparing to EBV-negative gastric cancers. However, the prevalence of EBVaGC has never been studied in Gansu Province, Northwest China. The present study investigated the incidence, characteristics, and EBV messenger RNA (mRNA) profile of EBVaGC in this area. We have collected 270 stomach samples from gastric cancer patients and analyzed the presence of EBV DNA and EBV-encoded small RNAs (EBERs) by nested polymerase chain reaction (PCR) and in situ hybridization, respectively. The EBV mRNA profiling was investigated by quantitative reverse transcription PCR (qRT-PCR). EBV DNA was detected in 51/95 patients (53.7%), while EBER transcripts were detected in 18/270 patients (6.7%). EBER positivity was significantly associated with older age and less lymph node metastasis, but no obvious association with gender or histological type of tumors. The expression of EBV genes was observed with different patterns, and the mRNA of glycoprotein BMRF2 was detected in EBVaGC. The present study showed unique clinicopathological features and mRNA expression patterns of EBVaGC in Gansu Province, Northwest China, suggesting that geographic variation can contribute to new epidemiological features in EBVaGC. The transcript of glycoprotein BMRF2 was observed consistently in EBVaGC, which may serve as a biomarker and play a role in the pathogenesis of EBVaGC in Gansu Province, Northwest China.