Selected flavonoid compounds as promising inhibitors of protein kinase CK2α and CK2α', the catalytic subunits of CK2

CK2 is a ubiquitous protein kinase involved in many cell functions. During the last years it became an interesting target in cancer research. A series of flavonoid compounds was tested as inhibitors of protein kinase CK2. Several substances were found to be highly active against both catalytic subunits with IC 50 values below 1 μM in case of CK2α′. The most promising inhibitor we identified is chrysoeriol with IC 50 values of 250 and 34 nM for CK2α and CK2α′, respectively.