RESUMO
In this article we describe the identification of unprecedented ATP-competitive ChoKα inhibitors starting from initial hit NMS-P830 that binds to ChoKα in an ATP concentration-dependent manner. This result is confirmed by the co-crystal structure of NMS-P830 in complex with Δ75-ChoKα. NMS-P830 is able to inhibit ChoKα in cells resulting in the reduction of intracellular phosphocholine formation. A structure-based medicinal chemistry program resulted in the identification of selective compounds that have good biochemical activity, solubility and metabolic stability and are suitable for further optimization. The ChoKα inhibitors disclosed in this article demonstrate for the first time the possibility to inhibit ChoKα with ATP-competitive compounds.
Assuntos
Trifosfato de Adenosina/antagonistas & inibidores , Colina Quinase/antagonistas & inibidores , Cicloexanos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Trifosfato de Adenosina/metabolismo , Colina Quinase/metabolismo , Cicloexanos/síntese química , Cicloexanos/química , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Relação Estrutura-AtividadeRESUMO
Maternal embryonic leucine zipper kinase (MELK) is upregulated in several types of tumor, including breast, prostate, and brain tumors. Its expression is generally associated with cell survival, cell proliferation, and resistance to apoptosis. Therefore, the potential of MELK inhibitors as therapeutic agents is recently attracting considerable interest. Here we report the first structures of MELK in complex with AMP-PNP and with nanomolar inhibitors. Our studies shed light on the role of the MELK UBA domain, provide a characterization of the kinase active site, and identify key residues for achieving high potency, laying the groundwork for structure-based drug design efforts.
Assuntos
Antineoplásicos/química , Inibidores Enzimáticos/química , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/química , Adenilil Imidodifosfato/farmacologia , Antineoplásicos/farmacologia , Domínio Catalítico , Linhagem Celular Tumoral , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Ensaios de Triagem em Larga Escala , Humanos , Pirazóis/química , Pirazóis/farmacologiaRESUMO
As part of our drug discovery effort, we identified and developed 4,5-dihydro-1H-pyrazolo[4,3-h]quinazoline derivatives as PLK1 inhibitors. We now report the optimization of this class that led to the identification of NMS-P937, a potent, selective and orally available PLK1 inhibitor. Also, in order to understand the source of PLK1 selectivity, we determined the crystal structure of PLK1 with NMS-P937. The compound was active in vivo in HCT116 xenograft model after oral administration and is presently in Phase I clinical trials evaluation.