Cdk9 Inhibitor II is an ATP-competitive inhibitor of cyclin-dependent kinase 9 (Cdk9; IC50 = 350 nM) and moderate inhibitor of similar enzymes including Cdk2-cyclin E. In the HT-29 cancer cell line, Cdk9 inhibitor II was observed to attenuate the frequency of the S-phase. Other Cdk9 Inhibitor II effects were shown to involve inhibition of mRNA synthesis, induction of p53, inhibition of IL-6 signaling and reduced phosphorylation of both retinoblastoma protein and RNA polymerase II at the C-terminal domain. Cdk9 Inhibitor II has been observed to be an effective antitumor and antimetastatic agent by disrupting TNFα signaling.
Cdk9 Inhibitor II is an inhibitor of Cdk4, cyclin D1 and p70 S6 Kinase.