EPHA2 and neoplasm: In the mechanism of ligand-dependent inhibition and ligand-independent promotion, EphA2 phosphorylation has opposite effects in tumorigenesis: ligand-independent EphA2 Ser897 phosphorylation promotes tumor growth and progression [18–20], while ligand-dependent EphA2 Tyr772 phosphorylation inhibits cell growth, migration and invasion [21, 22].