title: The evolution of protein kinase inhibitors from antagonists to agonists of cellular signaling.
abstract: Kinases are highly regulated enzymes with diverse mechanisms controlling their catalytic output. Over time, chemical discovery efforts for kinases have produced ATP-competitive compounds, allosteric regulators, irreversible binders, and highly specific inhibitors. These distinct classes of small molecules have revealed many novel aspects about kinase-mediated signaling, and some have progressed from simple tool compounds into clinically validated therapeutics. This review explores several small-molecule inhibitors for kinases highlighting elaborate mechanisms by which kinase function is modulated. A complete surprise of targeted kinase drug discovery has been the finding of ATP-competitive inhibitors that behave as agonists, rather than antagonists, of their direct kinase target. These studies hint at a connection between ATP-binding site occupancy and networks of communication that are independent of kinase catalysis. Indeed, kinase inhibitors that induce changes in protein localization, protein-protein interactions, and even enhancement of catalytic activity of the target kinase have been found. The relevance of these findings to the therapeutic efficacy of kinase inhibitors and to the future identification of new classes of drug targets is discussed.
authors.affiliation: Howard Hughes Medical Institute and Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California 94158, USA. dar@cmp.ucsf.edu
authors.forename: Arvin C
authors.initials: AC
authors.lastname: Dar
authors.forename: Kevan M
authors.initials: KM
authors.lastname: Shokat
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D019295:Computational Biology; D055808:Drug Discovery; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009154:Mutation; D009369:Neoplasms / Q000201:enzymology / Q000235:genetics; D011487:Protein Conformation; D047428:Protein Kinase Inhibitors / Q000737:chemistry* / Q000378:metabolism* / Q000494:pharmacology*; D011494:Protein Kinases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment; D015398:Signal Transduction / Q000187:drug effects*
chemical_list: D047428:Protein Kinase Inhibitors; D000255:Adenosine Triphosphate; D011494:Protein Kinases