RESUMEN
PURPOSE: The Ras-Raf-mitogen-activated protein kinase kinase (MEK) pathway is overactive in many human cancers and is thus a target for novel therapeutics. We have developed a highly potent and selective inhibitor of MEK1/2. The purpose of these studies has been to show the biological efficacy of ARRY-142886 (AZD6244) in enzymatic, cellular, and animal models. EXPERIMENTAL DESIGN: The ability of ARRY-142886 to inhibit purified MEK1 as well as other kinases was evaluated. Its effects on extracellular signal-regulated kinase (ERK) phosphorylation and proliferation in several cell lines were also determined. Finally, the inhibitor was tested in HT-29 (colorectal) and BxPC3 (pancreatic) xenograft tumor models. RESULTS: The IC(50) of ARRY-142886 was determined to be 14 nmol/L against purified MEK1. This activity is not competitive with ATP, which is consistent with the high specificity of compound for MEK1/2. Basal and epidermal growth factor-induced ERK1/2 phosphorylation was inhibited in several cell lines as well as 12-O-tetradecanoylphorbol-13-acetate-induced ERK1/2 phosphorylation in isolated peripheral blood mononuclear cells. Treatment with ARRY-142886 resulted in the growth inhibition of several cell lines containing B-Raf and Ras mutations but had no effect on a normal fibroblast cell line. When dosed orally, ARRY-142886 was capable of inhibiting both ERK1/2 phosphorylation and growth of HT-29 xenograft tumors in nude mice. Tumor regressions were also seen in a BxPC3 xenograft model. In addition, tumors remained responsive to growth inhibition after a 7-day dosing holiday. CONCLUSIONS: ARRY-142886 is a potent and selective MEK1/2 inhibitor that is highly active in both in vitro and in vivo tumor models. This compound is currently being investigated in clinical studies.
Asunto(s)
Bencimidazoles/farmacología , Inhibidores Enzimáticos/farmacología , MAP Quinasa Quinasa 1/efectos de los fármacos , MAP Quinasa Quinasa 2/efectos de los fármacos , Animales , Western Blotting , Proliferación Celular/efectos de los fármacos , Humanos , Concentración 50 Inhibidora , Ratones , Proteína Quinasa 3 Activada por Mitógenos/efectos de los fármacos , Fosforilación/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The role of MEK 1,2 in cancer tumorgenesis has been clearly demonstrated preclinically, and two selective inhibitors are currently undergoing clinical evaluation to determine their role in the human disease. We have discovered 4-(4-bromo-2-fluorophenylamino)-1-methylpyridin-2(1H)-ones as a new class of ATP noncompetitive MEK inhibitors. These inhibitors exhibit excellent cellular potency and good pharmacokinetic properties and have demonstrated the ability to inhibit ERK phosphorylation in HT-29 tumors from mouse xenograft studies.
Asunto(s)
Compuestos de Anilina/síntesis química , Antineoplásicos/síntesis química , MAP Quinasa Quinasa 1/antagonistas & inhibidores , MAP Quinasa Quinasa 2/antagonistas & inhibidores , Piridinas/síntesis química , Compuestos de Anilina/farmacocinética , Compuestos de Anilina/farmacología , Animales , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Línea Celular , Línea Celular Tumoral , Permeabilidad de la Membrana Celular , Supervivencia Celular/efectos de los fármacos , Estabilidad de Medicamentos , Hepatocitos/metabolismo , Humanos , Técnicas In Vitro , Ratones , Fosforilación , Piridinas/farmacocinética , Piridinas/farmacología , Ratas , Solubilidad , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Cholesteryl ester transfer protein is a plasma glycoprotein that transfers cholesterol ester between lipoprotein particles. Inhibition of this protein, in vitro and in vivo, produces an increase in plasma high density lipoprotein cholesterol (HDL-C). This communication will describe the SAR and synthesis of a series of substituted tetrahydroquinoxaline CETP inhibitors from early mu lead to advanced enantiomerically pure analogs.