Open AccessIdentification of Inhibitors of Checkpoint Kinase 1 through Template Screening
Author(s) -
Thomas P. Matthews,
Suki Klair,
Samantha Burns,
Kathy Boxall,
Michael Cherry,
Martin Fisher,
Isaac M. Westwood,
Michael I. Walton,
T. McHardy,
Kwai-Ming J. Cheung,
Rob van Montfort,
D. H. Williams,
G. Wynne Aherne,
Michelle D. Garrett,
John Reader,
Ian Collins
Publication year - 2009
Publication title -
journal of medicinal chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.01
H-Index - 261
eISSN - 1520-4804
pISSN - 0022-2623
DOI - 10.1021/jm900314j
Subject(s) - in silico , chemistry , ligand efficiency , chek1 , kinase , computational biology , small molecule , ligand (biochemistry) , dna , cell cycle checkpoint , combinatorial chemistry , biochemistry , cancer research , cell cycle , cell , biology , receptor , gene
Checkpoint kinase 1 (CHK1) is an oncology target of significant current interest. Inhibition of CHK1 abrogates DNA damage-induced cell cycle checkpoints and sensitizes p53 deficient cancer cells to genotoxic therapies. Using template screening, a fragment-based approach to small molecule hit generation, we have identified multiple CHK1 inhibitor scaffolds suitable for further optimization. The sequential combination of in silico low molecular weight template selection, a high concentration biochemical assay and hit validation through protein-ligand X-ray crystallography provided 13 template hits from an initial in silico screening library of ca. 15000 compounds. The use of appropriate counter-screening to rule out nonspecific aggregation by test compounds was essential for optimum performance of the high concentration bioassay. One low molecular weight, weakly active purine template hit was progressed by iterative structure-based design to give submicromolar pyrazolopyridines with good ligand efficiency and appropriate CHK1-mediated cellular activity in HT29 colon cancer cells.