CDK4 and acute lymphoblastic leukemia: In addition, a recently described CDK7 inhibitor, THZ1, suppressed RUNX1 expression in T–ALL cells (16), and additionally, mutations in Cyclin D2 suggested that t(8;21) might up-regulate CDK4/6 activity to circumvent the inhibition of cell cycle progression by AML1-ETO (AE) expression (44–47).