RESUMEN
Vps34 (the human class III phosphoinositide 3-kinase) is a lipid kinase involved in vesicle trafficking and autophagy and therefore constitutes an interesting target for cancer treatment. Because of the lack of specific Vps34 kinase inhibitors, we aimed to identify such compounds to further validate the role of this lipid kinase in cancer maintenance and progression. Herein, we report the discovery of a series of tetrahydropyrimidopyrimidinone derivatives. Starting with hit compound 1a, medicinal chemistry optimization led to compound 31. This molecule displays potent activity, an exquisite selectivity for Vps34 with excellent properties. The X-ray crystal structure of compound 31 in human Vps34 illustrates how the unique molecular features of the morpholine synthon bestows selectivity against class I PI3Ks. This molecule exhibits suitable in vivo mouse PK parameters and induces a sustained inhibition of Vps34 upon acute administration. Compound 31 constitutes an optimized Vps34 inhibitor that could be used to investigate human cancer biology.
Asunto(s)
Antineoplásicos/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Fosfatidilinositol 3-Quinasas Clase III/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Neoplasias/tratamiento farmacológico , Pirimidinonas/farmacología , Secuencia de Aminoácidos , Animales , Antineoplásicos/química , Antineoplásicos/metabolismo , Área Bajo la Curva , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacocinética , Células CACO-2 , Línea Celular Tumoral , Fosfatidilinositol 3-Quinasas Clase III/química , Fosfatidilinositol 3-Quinasas Clase III/metabolismo , Cristalografía por Rayos X , Descubrimiento de Drogas , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacocinética , Células HeLa , Humanos , Masculino , Ratones SCID , Modelos Químicos , Modelos Moleculares , Datos de Secuencia Molecular , Estructura Molecular , Neoplasias/patología , Unión Proteica , Estructura Terciaria de Proteína , Pirimidinonas/química , Pirimidinonas/farmacocinética , Ratas Sprague-Dawley , Homología de Secuencia de Aminoácido , Termodinámica , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Compelling molecular biology publications have reported the implication of phosphoinositide kinase PI3Kß in PTEN-deficient cell line growth and proliferation. These findings supported a scientific rationale for the development of PI3Kß-specific inhibitors for the treatment of PTEN-deficient cancers. This paper describes the discovery of 2-[2-(2,3-dihydro-indol-1-yl)-2-oxo-ethyl]-6-morpholin-4-yl-3H-pyrimidin-4-one (7) and the optimization of this new series of active and selective pyrimidone indoline amide PI3Kß inhibitors. 2-[2-(2-Methyl-2,3-dihydro-indol-1-yl)-2-oxo-ethyl]-6-morpholin-4-yl-3H-pyrimidin-4-one (28), identified following a carefully designed methyl scan, displayed improved physicochemical and in vitro pharmacokinetic properties. Structural biology efforts enabled the acquisition of the first X-ray cocrystal structure of p110ß with the selective inhibitor compound 28 bound to the ATP site. The nonplanar binding mode described herein is consistent with observed structure-activity relationship for the series. Compound 28 demonstrated significant in vivo activity in a UACC-62 xenograft model in mice, warranting further preclinical investigation. Following successful development, compound 28 entered phase I/Ib clinical trial in patients with advanced cancer.