CC-90009 can co-opt the CUL4-DDB1-CRBN-RBX1 (CRL4CRBN) E3 ubiquitin ligase complex to target G1 to S phase transition 1 (GSPT1) selectively for ubiquitination and proteasomal degradation, inducing AML apoptosis (Hansen et al., 2021). Here, DDB1 is linked to acute myeloid leukemia.