Discovery of a potent, highly selective, and orally bioavailable inhibitor of CDK8 through a structure-based optimisation

  • Eur J Med Chem. 2021 Jun 5:218:113391. doi: 10.1016/j.ejmech.2021.113391.
Mingfeng Yu  1 Yi Long  1 Yuchao Yang  1 Manjun Li  1 Theodosia Teo  1 Benjamin Noll  1 Stephen Philip  1 Shudong Wang  2
Affiliations
  • 1. Drug Discovery and Development, Cancer Research Institute, Clinical and Health Sciences, University of South Australia, Adelaide, South Australia, 5000, Australia.
  • 2. Drug Discovery and Development, Cancer Research Institute, Clinical and Health Sciences, University of South Australia, Adelaide, South Australia, 5000, Australia. Electronic address: [email protected].
Abstract

CDK8 is deregulated in multiple types of human Cancer and is viewed as a therapeutic target for the treatment of the disease. Accordingly, the search for small-molecule inhibitors of CDK8 is being intensified. Capitalising on our initial discovery of AU1-100, a potent CDK8 Inhibitor yet with a limited degree of kinase selectivity, a structure-based optimisation was carried out, with a series of new multi-substituted pyridines rationally designed, chemically prepared and biologically evaluated. Such endeavour has culminated in the identification of 42, a more potent CDK8 Inhibitor with superior kinomic selectivity and oral bioavailability. The mechanism underlying the anti-proliferative effect of 42 on MV4-11 cells was studied, revealing that the compound arrested the G1 cell cycle and triggered Apoptosis. The low risk of hepato- and cardio-toxicity of 42 was estimated. These findings merit further investigation of 42 as a targeted Cancer therapeutic.

Keywords
Anti-proliferation mechanism; CDK8 inhibitor; Kinase selectivity; MV4-11; Oral bioavailability; Structure-based optimisation.