Flavopiridol is a synthetic flavonoid based on an extract from Dysoxylum binectariferum which has shown potential for treatment of cancer in vitro. Flavopiridol hydrochloride is a potent inhibitor of cyclin-dependent kinases (primarily Cdk1, Cdk2, and Cdk4) with an IC50 of 100 nM. The (-)-cis form induces apoptosis in particular tumor cells. At nanomolar concentrations, flavoporidol hydrochloride has been shown to reduce rhabdoid cell growth with an IC50 ranging from 50 to 200 nM. Treatment of flavopiridol decreased the activities of Cdk2 and potently prevented cell proliferation with an IC50 ranging from 43 to 83 nM in HNSCC cells.
