NU6102

Cyclin-dependent kinases (CDKs) play a key role in regulating cell division by phosphorylating distinct substrates in different phases of the cell cycle. Cell cycle deregulation in many cancers often results from altered CDK activity. Thus, CDKs are potential pharmacological targets for anticancer agents. NU 6102 is a potent inhibitor of Cdk1 and Cdk2 with Ki values of 9 and 6 nM and IC50 values of 9.5 and 5.4 nM, respectively. NU 6102 inhibits Cdk4 activity with an IC50 value of 1.6 μM, suggesting it is most selective for Cdk2. Time-lapse videomicroscopy reveals that 20 μM NU 6102 delays cell entry into mitosis where most cells appear to eventually complete mitotic division but cannot correctly undergo cytokinesis, and hence become binucleated with an abnormal number of centrosomes. In SKUT-1B cancer cells a 24 h exposure to NU 6102 induced G2 arrest, inhibition of target protein phosphorylation, and cytotoxicity with an LC50 value of 2.6 μM.