CD274 and nasopharyngeal carcinoma: Furthermore, Epstein–Barr virus (EBV) infection is a major risk factor for the development of NPC in the endemic regions6,7, upregulation of programmed cell death-ligand 1 (PDL1) was found in EBV-driven NPC cells, it is reported that PDL1 (CD274) expression on NPC is associated with a poor outcome8, this suggests that the development of NPC may be closely related to the immune escape of tumor cells.