ERN1 and acute myeloid leukemia: In AML cells, treatment with IRE1α inhibitors led to inhibition of cyclin D1, cyclin-dependent kinase 4 (CDK4), Bcl-2, c-Myc, and to an induction of p21cip1 and p27kip1, thereby causing both a G1 phase cell cycle arrest and a caspase-dependent apoptosis.