RESUMEN
Overexpression of the antiapoptotic protein Mcl-1 provides a survival advantage to some cancer cells, making inhibition of this protein an attractive therapeutic target for the treatment of certain types of tumors. Herein, we report our efforts toward the identification of a novel series of macrocyclic Mcl-1 inhibitors featuring an α-hydroxy phenylacetic acid pharmacophore or bioisostere. This work led to the discovery of 1, a potent Mcl-1 inhibitor (IC50 = 19 nM in an OPM-2 cell viability assay) with good pharmacokinetic properties and excellent in vivo efficacy in an OPM-2 multiple myeloma xenograft model.
Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/antagonistas & inhibidores , Fenilacetatos/química , Administración Oral , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacocinética , Disponibilidad Biológica , Línea Celular Tumoral , Cristalografía por Rayos X , Diseño de Fármacos , Estabilidad de Medicamentos , Femenino , Humanos , Enlace de Hidrógeno , Ratones Desnudos , Mieloma Múltiple/tratamiento farmacológico , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/química , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Ratas Sprague-Dawley , Relación Estructura-Actividad , Sulfonamidas/química , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Proteolysis targeting chimeras (PROTACs) are bispecific molecules containing a target protein binder and an ubiquitin ligase binder connected by a linker. By recruiting an ubiquitin ligase to a target protein, PROTACs promote ubiquitination and proteasomal degradation of the target protein. The generation of effective PROTACs depends on the nature of the protein/ligase ligand pair, linkage site, linker length, and linker composition, all of which have been difficult to address in a systematic way. Herein, we describe a "click chemistry" approach for the synthesis of PROTACs. We demonstrate the utility of this approach with the bromodomain and extraterminal domain-4 (BRD4) ligand JQ-1 (3) and ligase binders targeting cereblon (CRBN) and Von Hippel-Lindau (VHL) proteins. An AlphaScreen proximity assay was used to determine the ability of PROTACs to form the ternary ligase-PROTAC-target protein complex and a MSD assay to measure cellular degradation of the target protein promoted by PROTACs.
Asunto(s)
Química Clic , Evaluación Preclínica de Medicamentos , Proteínas Nucleares , Proteolisis , Factores de Transcripción , Humanos , Proteínas Adaptadoras Transductoras de Señales , Proteínas de Ciclo Celular , Química Clic/métodos , Evaluación Preclínica de Medicamentos/métodos , Ligandos , Proteínas Nucleares/metabolismo , Péptido Hidrolasas/genética , Péptido Hidrolasas/metabolismo , Péptidos/farmacología , Proteolisis/efectos de los fármacos , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacología , Factores de Transcripción/metabolismo , Ubiquitina-Proteína Ligasas , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismoRESUMEN
A high-throughput screen resulted in the discovery of benzoxazepine 1, an EP2 antagonist possessing low microsomal stability and potent CYP3A4 inhibition. Modular optimization of lead compound 1 resulted in the discovery of benzoxazepine 52, a molecule with single-digit nM binding affinity for the EP2 receptor and significantly improved microsomal stability. It was devoid of CYP inhibition and was â¼4000-fold selective against the other EP receptors. Compound 52 was shown to have good PK properties in CD-1 mice and high CNS permeability in C57Bl/6s mice and Sprague-Dawley rats. In an ex vivo assay, it demonstrated the ability to increase the macrophage-mediated clearance of amyloid-beta plaques from brain slices in a dose-dependent manner.