RESUMEN
The p53-MDM2 interaction is an anticancer drug target under investigation in the clinic. Our compound NVP-CGM097 is one of the small molecule inhibitors of this protein-protein interaction currently evaluated in cancer patients. As part of our effort to identify new classes of p53-MDM2 inhibitors that could lead to additional clinical candidates, we report here the design of highly potent inhibitors having a pyrazolopyrrolidinone core structure. The conception of these new inhibitors originated in a consideration on the MDM2 bound conformation of the dihydroisoquinolinone class of inhibitors to which NVP-CGM097 belongs. This work forms the foundation of the discovery of HDM201, a second generation p53-MDM2 inhibitor that recently entered phase I clinical trial.
Asunto(s)
Descubrimiento de Drogas , Proteínas Proto-Oncogénicas c-mdm2/antagonistas & inhibidores , Proteína p53 Supresora de Tumor/antagonistas & inhibidores , Cristalografía por Rayos X , Transferencia Resonante de Energía de Fluorescencia , Conformación Molecular , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
Blocking the interaction between the p53 tumor suppressor and its regulatory protein MDM2 is a promising therapeutic concept under current investigation in oncology drug research. We report here the discovery of the first representatives of a new class of small molecule inhibitors of this protein-protein interaction: the dihydroisoquinolinones. Starting from an initial hit identified by virtual screening, a derivatization program has resulted in compound 11, a low nanomolar inhibitor of the p53-MDM2 interaction showing significant cellular activity. Initially based on a binding mode hypothesis, this effort was then guided by a X-ray co-crystal structure of MDM2 in complex with one of the synthesized analogs. The X-ray structure revealed an unprecedented binding mode for p53-MDM2 inhibitors.
Asunto(s)
Isoquinolinas/química , Isoquinolinas/farmacología , Mapas de Interacción de Proteínas/efectos de los fármacos , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Cristalografía por Rayos X , Humanos , Simulación del Acoplamiento Molecular , Unión Proteica/efectos de los fármacos , Proteínas Proto-Oncogénicas c-mdm2/antagonistas & inhibidores , Relación Estructura-Actividad , Proteína p53 Supresora de Tumor/antagonistas & inhibidoresRESUMEN
Capitalizing on crystal structure information obtained from a previous effort in the search for non peptide inhibitors of the p53-MDM2 interaction, we have discovered another new class of compounds able to disrupt this protein-protein interaction, an important target in oncology drug research. The new inhibitors, based on a tetra-substituted imidazole scaffold, have been optimized to low nanomolar potency in a biochemical assay following a structure-guided approach. An appropriate strategy has allowed us to translate the high biochemical potency in significant anti-proliferative activity on a p53-dependent MDM2 amplified cell line.