CKI-7

CKI-7 is a potent and ATP-competitive casein kinase 1 (CK1) inhibitor with an IC₅₀ of 6 μM and a K_i of 8.5 μM. CKI-7 is a selective Cdc7 kinase inhibitor. CKI-7 also inhibits SGK, ribosomal S6 kinase-1 (S6K1) and mitogen- and stress-activated protein kinase-1 (MSK1). CKI-7 has a much weaker effect on casein kinase II and other protein kinases^[1][2][3][4]. In Vitro: CKI-7 (0.1-10 μM; 5 days; ES cells) treatment significantly increases the expression of the early neuroectodermal marker Sox1 and the number of cells positive for the neural markers nestin and βIII-tubulin, in a concentration-dependent manner^[1].
CKI-7 (5 μM; 5 days; ES cells) treatment suppresses SFEB-induced β-catenin stabilization on day 5, indicating that CKI-7 inhibits Wnt signaling^[1]. In Vivo: In vivo dose-dependent anti-tumor activity of CKI-7 is demonstrated in a SCID-Beige mouse systemic tumor model utilzing a recently isolated Philadelphia chromosome positive acute lymphoblastic leukemia cell line. Standard cell cycle synchronization studies established that exposure to CKI-7 results in cell cycle dependent caspase 3 activation and apoptotic cell death^[2].