CTLA4 and gastric cancer: Immunotherapeutic targets for GC have been identified, leading to the development of drugs that specifically target Human Epidermal Growth Factor Receptor 2 (HER2), Vascular Endothelial Growth Factor Receptor 2 (VEGFR2), cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4), PD-1, and programmed cell death ligand 1 (PD-L1).