As two representative immune checkpoints that are often overexpressed on the surface of cancer cells, PD-L1 is responsible for evading attack by the adaptive immune system, while CD47 is the major contributor to resistance to innate immune phagocytosis by interacting with its ligands including platelet reactive protein-1 (TSP-1), signal-regulatory protein-α (SIRP-α), integrin, and protein tyrosine phosphatase substrate 1 (SHPS-1) carrying the SH2 domain [67, 68]. This evidence concerns the gene SIRPA and cancer.