PIM1 and leukemia: Moreover, palbociclib treatment in FLT3-ITD AML decreases the mRNA expression for FLT3 and PIM1.[28] FLT3 kinase activity activates the signal transducer and activator of transcription 5, phosphoinositide 3-kinase/protein kinase B (PI3K/AKT), and mitogen-activated protein kinase signaling pathways and plays a dominant role in cell survival, proliferation, and differentiation.[38] Meanwhile, PIM1, a downstream of FLT3-ITD, is essential for leukemia proliferation and its anti-apoptotic effect.