CCT251545 is an orally bioavailable and potent inhibitor of WNT signaling with IC50 value of 5 nM [1].
The WNT signaling network controls cellular functions such as proliferation and differentiation, and is a major regulator of mammalian development. WNT signaling is frequently deregulated in malignancy, especially in colon cancer, and plays an important role in the generation and maintenance of cancer stem cells [1].
CCT251545 is an orally bioavailable and potent WNT signaling inhibitor discovered through high-throughput cell-based screening. CCT251545 is also a potent and selective chemical probe for the human Mediator complex-associated protein kinases CDK8 and CDK19. CCT251545 changed gene expression regulated by WNT pathway and other on-target effects of modulating CDK8 and CDK19, including expression of genes regulated by STAT1 [2]. CCT251545 also inhibited GSK3α and -β with IC50 values of 0.462 and 0.690 μM. In APC mutant human colorectal cancer cell line (COLO205-F1756 clone 4), CCT251545 inhibited WNT pathway activity with IC50 value of 0.035 nM [1].
In both mouse and rat, CCT251545 exhibited moderate clearance with moderate to high oral bioavailability. In mice bearing COLO205-F1756 clone 4 tumor xenografts, CCT251545 (70 mg/kg po bid for 9 days) significantly inhibited WNT signaling and reduced tumor weights by 37.5% [1].
References:
[1]. Mallinger A, Crumpler S, Pichowicz M, et al. Discovery of potent, orally bioavailable, small-molecule inhibitors of WNT signaling from a cell-based pathway screen. J Med Chem, 2015, 58(4): 1717-1735.
[2]. Dale T, Clarke PA, Esdar C, et al. A selective chemical probe for exploring the role of CDK8 and CDK19 in human disease. Nat Chem Biol, 2015, 11(12): 973-980.