MAPK3 and neoplasm: ERK1/2 has been shown to be indispensable for neutrophil phagocytosis, acting downstream of the tyrosine kinase Syk, which is crucial for cytoskeletal rearrangements.57 A PI3K-dependent signal transition of Rho-family GTPase activities occurs during FcR-mediated phagocytosis and PI3K-dependent deactivation of Cdc42 at the signal transition is necessary for phagocytosis.58 Our findings suggest that ICAM-1 inhibits tumor metastasis through impairing efferocytosis, which is involved in blockade of PI3K/AKT signaling.