RESUMEN
The Aurora kinases are essential for cell mitosis, and the dysregulation of Aurora A and B have been linked to the etiology of human cancers. Investigational agents MLN8054 (8) and alisertib (MLN8237, 10) have been identified as high affinity, selective, orally bioavailable inhibitors of Aurora A that have advanced into human clinical trials. Alisertib (10) is currently being evaluated in multiple Phase II and III clinical trials in hematological malignancies and solid tumors.
RESUMEN
Plk1 is a checkpoint protein whose role spans all of mitosis and includes DNA repair, and is highly conserved in eukaryotes from yeast to man. Consistent with this wide array of functions for Plk1, the cellular consequences of Plk1 disruption are diverse, spanning delays in mitotic entry, mitotic spindle abnormalities, and transient mitotic arrest leading to mitotic slippage and failures in cytokinesis. In this work, we present the in vitro and in vivo consequences of Plk1 inhibition in cancer cells using potent, selective small-molecule Plk1 inhibitors and Plk1 genetic knock-down approaches. We demonstrate for the first time that cellular senescence is the predominant outcome of Plk1 inhibition in some cancer cell lines, whereas in other cancer cell lines the dominant outcome appears to be apoptosis, as has been reported in the literature. We also demonstrate strong induction of DNA double-strand breaks in all six lines examined (as assayed by γH2AX), which occurs either during mitotic arrest or mitotic-exit, and may be linked to the downstream induction of senescence. Taken together, our findings expand the view of Plk1 inhibition, demonstrating the occurrence of a non-apoptotic outcome in some settings. Our findings are also consistent with the possibility that mitotic arrest observed as a result of Plk1 inhibition is at least partially due to the presence of unrepaired double-strand breaks in mitosis. These novel findings may lead to alternative strategies for the development of novel therapeutic agents targeting Plk1, in the selection of biomarkers, patient populations, combination partners and dosing regimens.
Asunto(s)
Proteínas de Ciclo Celular/antagonistas & inhibidores , Senescencia Celular/efectos de los fármacos , Senescencia Celular/genética , Daño del ADN/efectos de los fármacos , Mitosis/genética , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Puntos de Control del Ciclo Celular/efectos de los fármacos , Puntos de Control del Ciclo Celular/genética , Línea Celular Tumoral , Humanos , Mitosis/efectos de los fármacos , Interferencia de ARN , ARN Interferente Pequeño/genética , Quinasa Tipo Polo 1RESUMEN
Diffuse large B-cell lymphoma (DLBCL) is the most common of the non-Hodgkin lymphomas, accounting for up to 30% of all newly diagnosed lymphoma cases. Current treatment options for this disease are effective, but not always curative; therefore, experimental therapies continue to be investigated. We have discovered an experimental, potent, and selective small-molecule inhibitor of PLK1, MLN0905, which inhibits cell proliferation in a broad range of human tumor cells including DLBCL cell lines. In our report, we explored the pharmacokinetic, pharmacodynamic, and antitumor properties of MLN0905 in DLBCL xenograft models grown in mice. These studies indicate that MLN0905 modulates the pharmacodynamic biomarker phosphorylated histone H3 (pHisH3) in tumor tissue. The antitumor activity of MLN0905 was evaluated in three human subcutaneous DLBCL xenograft models, OCI LY-10, OCI LY-19, and PHTX-22L (primary lymphoma). In each model, MLN0905 yielded significant antitumor activity on both a continuous (daily) and intermittent dosing schedule, underscoring dosing flexibility. The antitumor activity of MLN0905 was also evaluated in a disseminated xenograft (OCI LY-19) model to better mimic human DLBCL disease. In the disseminated model, MLN0905 induced a highly significant survival advantage. Finally, MLN0905 was combined with a standard-of-care agent, rituximab, in the disseminated OCI LY-19 xenograft model. Combining rituximab and MLN0905 provided both a synergistic antitumor effect and a synergistic survival advantage. Our findings indicate that PLK1 inhibition leads to pharmacodynamic pHisH3 modulation and significant antitumor activity in multiple DLBCL models. These data strongly suggest evaluating PLK1 inhibitors as DLBCL anticancer agents in the clinic.
Asunto(s)
Anticuerpos Monoclonales de Origen Murino/administración & dosificación , Antineoplásicos/administración & dosificación , Benzazepinas/administración & dosificación , Proteínas de Ciclo Celular/antagonistas & inhibidores , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Tionas/administración & dosificación , Administración Oral , Animales , Anticuerpos Monoclonales de Origen Murino/farmacología , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Benzazepinas/farmacocinética , Benzazepinas/farmacología , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Sinergismo Farmacológico , Femenino , Técnicas de Silenciamiento del Gen , Histonas/metabolismo , Ratones , Ratones Endogámicos NOD , Ratones SCID , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Interferencia de ARN , Rituximab , Tionas/farmacocinética , Tionas/farmacología , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Quinasa Tipo Polo 1RESUMEN
This article describes the discovery of a series of potent inhibitors of Polo-like kinase 1 (PLK1). Optimization of this benzolactam-derived chemical series produced an orally bioavailable inhibitor of PLK1 (12c, MLN0905). In vivo pharmacokinetic-pharmacodynamic experiments demonstrated prolonged mitotic arrest after oral administration of 12c to tumor bearing nude mice. A subsequent efficacy study in nude mice achieved tumor growth inhibition or regression in a human colon tumor (HT29) xenograft model.
Asunto(s)
Antineoplásicos/síntesis química , Benzazepinas/síntesis química , Proteínas de Ciclo Celular/antagonistas & inhibidores , Lactamas/síntesis química , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Tionas/síntesis química , Administración Oral , Animales , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Benzazepinas/farmacocinética , Benzazepinas/farmacología , Disponibilidad Biológica , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cristalografía por Rayos X , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Lactamas/farmacocinética , Lactamas/farmacología , Ratones , Ratones Desnudos , Mitosis , Modelos Moleculares , Trasplante de Neoplasias , Conformación Proteica , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad , Tionas/farmacocinética , Tionas/farmacología , Trasplante Heterólogo , Quinasa Tipo Polo 1RESUMEN
Inhibition of mutant B-Raf signaling, through either direct inhibition of the enzyme or inhibition of MEK, the direct substrate of Raf, has been demonstrated preclinically to inhibit tumor growth. Very recently, treatment of B-Raf mutant melanoma patients with a selective B-Raf inhibitor has resulted in promising preliminary evidence of antitumor activity. This article describes the design and optimization of tetrahydronaphthalene-derived compounds as potent inhibitors of the Raf pathway in vitro and in vivo. These compounds possess good pharmacokinetic properties in rodents and inhibit B-Raf mutant tumor growth in mouse xenograft models.
Asunto(s)
Antineoplásicos/síntesis química , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Tetrahidronaftalenos/síntesis química , Administración Oral , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Disponibilidad Biológica , Cristalografía por Rayos X , Diseño de Fármacos , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/enzimología , Melanoma Experimental/patología , Ratones , Ratones Desnudos , Modelos Moleculares , Mutación , Proteínas Proto-Oncogénicas B-raf/genética , Estereoisomerismo , Relación Estructura-Actividad , Tetrahidronaftalenos/química , Tetrahidronaftalenos/farmacología , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
A high throughput screen identified N-aroylpyrazoline 1 as a selective inhibitor of the V600E mutant of B-Raf kinase. Parallel synthesis of acyl, aroyl, and sulfonyl derivatives led to the identification of several potent inhibitors in both enzymatic and cellular (pERK) assays such as compound 42.
Asunto(s)
Inhibidores de Proteínas Quinasas/química , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Pirazoles/química , Piridinas/química , Sustitución de Aminoácidos , Evaluación Preclínica de Medicamentos , Ensayos Analíticos de Alto Rendimiento , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Pirazoles/síntesis química , Pirazoles/farmacología , Piridinas/síntesis química , Piridinas/farmacología , Proteínas Recombinantes/antagonistas & inhibidores , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Relación Estructura-ActividadRESUMEN
The discovery of novel pyrazoline derivatives as B-Raf (V600E) inhibitors is described in this report. Chemical modification of the pyrazoline scaffold led to the development of SAR and identified potent and selective inhibitors of B-Raf (V600E). Determination of the pharmacokinetic properties of selected inhibitors is also reported.
Asunto(s)
Inhibidores de Proteínas Quinasas/química , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Pirazoles/química , Sustitución de Aminoácidos , Sitios de Unión , Simulación por Computador , Evaluación Preclínica de Medicamentos , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacocinética , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Pirazoles/síntesis química , Pirazoles/farmacocinética , Proteínas Recombinantes/antagonistas & inhibidores , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Relación Estructura-ActividadRESUMEN
Increased Aurora A expression occurs in a variety of human cancers and induces chromosomal abnormalities during mitosis associated with tumor initiation and progression. MLN8054 is a selective small-molecule Aurora A kinase inhibitor that has entered Phase I clinical trials for advanced solid tumors. MLN8054 inhibits recombinant Aurora A kinase activity in vitro and is selective for Aurora A over the family member Aurora B in cultured cells. MLN8054 treatment results in G(2)/M accumulation and spindle defects and inhibits proliferation in multiple cultured human tumor cells lines. Growth of human tumor xenografts in nude mice was dramatically inhibited after oral administration of MLN8054 at well tolerated doses. Moreover, the tumor growth inhibition was sustained after discontinuing MLN8054 treatment. In human tumor xenografts, MLN8054 induced mitotic accumulation and apoptosis, phenotypes consistent with inhibition of Aurora A. MLN8054 is a selective inhibitor of Aurora A kinase that robustly inhibits growth of human tumor xenografts and represents an attractive modality for therapeutic intervention of human cancers.
Asunto(s)
Antineoplásicos/farmacología , Benzazepinas/farmacología , Inhibidores Enzimáticos/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Administración Oral , Animales , Aurora Quinasa A , Aurora Quinasa B , Aurora Quinasas , Línea Celular Tumoral , Progresión de la Enfermedad , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Concentración 50 Inhibidora , Masculino , Ratones , Ratones Desnudos , Trasplante de NeoplasiasRESUMEN
The identification and optimization of a series of acylguanidine-based melanocortin-4 receptor antagonists is discussed.
Asunto(s)
Guanidina/química , Receptor de Melanocortina Tipo 4/antagonistas & inhibidores , Compuestos de Sulfhidrilo/química , Animales , Sitios de Unión , Encéfalo/metabolismo , Guanidina/análogos & derivados , Guanidina/farmacología , Concentración 50 Inhibidora , Ratones , Plasma/metabolismo , Relación Estructura-Actividad , Compuestos de Sulfhidrilo/farmacología , Factores de TiempoRESUMEN
The melanocortin 4 receptor (MC4R) plays an important role in body weight regulation and energy homeostasis. Administration of peptidic MC4R antagonists (usually by intracerebro ventricular injection) has been shown in the literature to increase body weight and/or food intake in several rodent models. We report here the identification of a novel nonpeptidic MC4R antagonist and its effects on tumor-induced weight loss in mice following peripheral administration.