CDK7 and cancer: A number of covalent CDK7 inhibitors have also been developed, the first being THZ1 (Fig. 3b, Table 3), which targets a cysteine residue (Cys312) on a C-terminal extension just outside the ATP-binding site of CDK7 [20, 132] and has strong activity in many cancer types (Table 3) [20, 21, 71, 75, 114–124].