CD274 and neoplasm: Indeed, the monoclonal antibodies (mAbs) blocking immune checkpoints such as Cytotoxic T-Lymphocyte Antigen (CTLA)-4 and Programed Death-Ligand1 (PD-L1)/Programed Death-1 (PD-1) showed extraordinary anti-tumor effects in clinical trials leading to their approval as anti-cancer drugs in different metastatic cancers2.