CD47 and neoplasm: Studies have shown that in various cancers, CRT is a major pro-phagocytic signal, and the increase in CRT expression on the tumor cell surface is positively correlated with the increase in CD47 expression, possibly based on a feedback regulation mechanism that balances the immune-suppressive signal mediated by CD47 and the phagocytic signal mediated by CRT [54,55,56,59].