The Epstein–Barr virus (EBV), also known as human herpesvirus 4, is a virus of the Herpesveridae family, and is one of the most common DNA viruses in humans. EBV infection is associated with several benign and malignant diseases, including Burkitt and some other types of lymphoma, nasopharyngeal carcinoma, and gastric cancer. Monoclonal EBV DNA is found in the tumor cells of about 9% of gastric adenocarcinomas, which have particular molecular characteristics (Comprehensive molecular characterization of gastric adenocarcinoma.Nature, 2014). The etiological significance of the viral infection is uncertain.
The NCI International EBV-Gastric Cancer Consortium is a collaboration among NCI and extramural investigators, established by DCEG in 2006. This Consortium utilizes data and biospecimens from completed and ongoing case series and observational studies of gastric cancer conducted in low- and high-risk populations. The presence of EBV in cancer cells is assessed by in situ hybridization for EBV-encoded RNA (EBER), the gold standard assay for detecting latent infection. This research effort was designed to replicate and extend findings from previous studies hindered by small numbers of EBV-positive cases, and to stimulate multidisciplinary research in this area. Analyses from this research group to date have focused on epidemiological and clinicopathological characterization of EBV-positive gastric cancer (Meta-analysis shows that prevalence of Epstein-Barr virus-positive gastric cancer differs based on sex and anatomic location.Gastroenterology, 2009; Determinants of Epstein-Barr virus-positive gastric cancer: An international pooled analysis.Br J Cancer, 2011; Improved survival of gastric cancer with tumour Epstein-Barr virus positivity: an international pooled analysis.Gut, 2014; Case-case comparison of smoking and alcohol risk associations with Epstein-Barr virus-positive gastric cancer.Int J Cancer, 2014). Laboratory studies comparing EBV-positive and -negative cases are currently underway addressing:
• Anti-EBV and anti-Helicobacter pylori antibody profiles
• Tissue expression of metabolic pathways
• Blood-based methods for diagnosis