Immune checkpoint inhibitors can be classified in gastrointestinal tumors depending on the target protein on the tumor or immune cells into three different groups: the anti-PD-1 antibodies nivolumab, pembrolizumab, tislelizumab, camrelizumab, sintilimab, toripalimab (T cells); the anti-PD-L1 antibodies atezolizumab, avelumab, and durvalumab (cancer cells, dendritic cells); and the anti-CTLA-4 antibody ipilimumab (T cells). Here, CD274 is linked to neoplasm.