Cdk4 Inhibitor

Cdk4 Inhibitor is a cell-permeable, unsymmetrical indolocarbazole compound that displays antiproliferative properties. Acts as a potent, selective, and ATP-competitive inhibitor of Cdk4/cyclin D1 (IC₅₀ = 76 nM). It inhibits the activity of other Cdk's only at much higher concentrations (IC₅₀ = 520 nM and 2.1 μM for Cdk2/cyclin E and Cdc2 (Cdk1)/cyclin B, respectively) and shows little activity towards CaMKII, PKA, or GSK-3b (IC₅₀ ≥ 12.4 μM). Shown to inhibit tumor cells growth (IC₅₀ < 3.0 μM in HCT-116 and NCI-H460 cells) by blocking Rb phosphorylation and inducing G1 cell cycle arrest.