As shown in Fig. 2a−d, ABBV-075 treatment attenuated MYC, BCL2, Bcl-xL, and CDK6, while inducing HEXIM1 and p21 mRNA levels in MV4-11, OCI-AML5, MOLM13, and PD CD34+ AML BPCs. Here, HEXIM1 is linked to acute myeloid leukemia.