FLT3 and acute myeloid leukemia: Mutations in FLT3 contribute to the development of AML as they cause self-phosphorylation and ligand-independent activation of the FLT3 receptor and downstream signaling pathways such as STAT3, STAT5, ERK1/2, and AKT (Hayakawa et al., 2000; Mizuki et al., 2000, 2003; Tse et al., 2000; Spiekermann et al., 2003).