CTLA4 and carcinoma of esophagus: Moreover, our study indicates that EBV and cytomegalovirus elevate PD-L1 or PD-L2, CD80, CD86, PD-1, CTLA-4, Tim-3, LAG3, and 4-1BB expression in multiple cancers along the gastrointestinal tract including stomach and esophageal carcinoma and colon and rectum adenocarcinoma.