CDK4 and cervical cancer: Toidentify potential chemical handles that could convert protein-targetingligands into molecular glue degraders of their targets, we appendedvarious moieties onto the solvent-exposed piperazine of the CDK4/6inhibitor ribociclib (Figure 1a).23 Among the nine initial ribociclibanalogs tested, we found one compound, EST1027, a trifluoromethylphenylcinnamamide, that led to >50% reduction in CDK4, but not CDK6,levelsin C33A cervical cancer cells treated for 24 h at 3 μM (Figures 1b–d and S1a).