FLT3 and acute myeloid leukemia: The significance of the FLT3 receptor and its downstream signaling pathways in AML led to the development of several inhibitory drugs (e.g., Sorafenib®, Quizartinib®, Midostaurin®) that are currently under investigation in different clinical trials [(38), reviewed in (39, 40)] or that are already EMA and FDA approved for the treatment of FLT3-positive AML (41, 42).