CTLA4 and cancer: Considering the expression of checkpoints varies among many cancer patients, including those with unique subtypes; cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), PD-1, receptor activator of nuclear factor kappa-B ligand (RANK-L), GD-2, IGF-1, TNF-related apoptosis-inducing ligand (TRAIL), and VEGF are potential targets in ICI therapy in patients with OS.