CD274 and cancer: Recent breakthroughs have highlighted phagocytosis checkpoint axes which can be targeted to induce the anti-cancer functions of macrophages, such as the CD47-SIRPα phagocytosis axis (41), PD1-PDL1 axis (10), MHC I–LILRB1 axis (42), and CD24–Siglec-10 axis (43).