Higher viral load of Epstein-Barr virus in gastric cancer compared with non-cancerous gastroduodenal tissues

Epstein-Barr Virus (EBV)-associated gastric cancer is a distinct molecular subtype of gastrointestinal carcinomas as defined by the Cancer Genome Atlas. In the present study 237 samples from Iranian patients diagnosed with gastric cancer and gastroduodenal disease were retrospectively examined for EBV infection by quantitative Real-Time PCR. Of the 237 samples tested, EBV DNA was detected in 37 samples (15.6%), in 13 of the 81 gastric cancer cases (16%), and 24 of the 156 non-cancerous samples (15.4%). The EBV infection rate was found higher in patients with gastric ulcer (35%) and duodenal ulcer (21.9%) compared to patients with gastric cancer (16%) and gastritis (19.6%). The EBV-encoded small RNA (EBER) copy number in the gastric cancer group (mean = 2.14×10 with range of 2.14×10 to 4.10×10 copies/ cell) was higher than gastroduodenal diseases group (mean = 1.39×10 with range 1.11×10 to 2.35×10 copies/ cell), and this difference was statistically significant (P >0.001). The higher number of copies of EBV-EBER in the gastric cancer group compared to the non-cancer group confirmed the possible role of EBV in inducing cancer.