CD47 and neoplasm: A high expression of MYC in tumor cells can regulate the tumor microenvironment by acting on innate immune cells and adaptive immune cells as well as cytokines, and activation of MYC can upregulate the expression of CD47 and PD-L1 leading to immunosuppression and tumor proliferation (MYC can directly act on the promoters of CD47 and PD-L1 and then regulate their mRNA and protein expression levels) (44).