Moreover, EBNA1, the only viral oncoprotein expressed in LCLs, all varieties of EBV-associated BL and other solid tumours such as nasopharyngeal carcinoma (NPC) and gastric carcinoma (EBVaGC), activates E2F1 expression at post-transcriptional level via PI3Kδ-dependent mRNA translation stress [55]. This evidence concerns the gene E2F1 and gastric carcinoma.