CTLA4 and gastric cancer: In addition, targeted therapeutic approaches (e.g., targeting human epidermal growth factor receptor 2 (HER2), Claudin 18-2 or tumor associated vessels), immunotherapy (e.g., anti-programmed death protein 1/ligand 1 (PD1/PD-L1), or anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA4) monoclonal antibodies (mAbs) significantly improved the outcome of gastric cancer patients in recent years [62,68,69].