RESUMEN
The lack of selective and safe in vivo IRE1α tool molecules has limited the evaluation of IRE1α as a viable target to treat multiple myeloma. Focus on improving the physicochemical properties of a literature compound by decreasing lipophilicity, molecular weight, and basicity allowed the discovery of a novel series with a favorable in vitro safety profile and good oral exposure. These efforts culminated in the identification of a potent and selective in vivo tool compound, G-5758, that was well tolerated following multiday oral administration of doses up to 500 mg/kg. G-5758 demonstrated comparable pharmacodynamic effects to induced IRE1 knockdown as measured by XBP1s levels in a multiple myeloma model (KMS-11).
Asunto(s)
Endorribonucleasas , Mieloma Múltiple , Proteínas Serina-Treonina Quinasas , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/patología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/metabolismo , Humanos , Administración Oral , Endorribonucleasas/antagonistas & inhibidores , Endorribonucleasas/metabolismo , Animales , Descubrimiento de Drogas , Ratones , Línea Celular Tumoral , Relación Estructura-Actividad , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Ratas , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacocinética , Técnicas de Silenciamiento del Gen , Proteína 1 de Unión a la X-Box/metabolismo , Proteína 1 de Unión a la X-Box/genéticaRESUMEN
Distinct T cell infiltration patterns, i.e., immune infiltrated, excluded, and desert, result in different responses to cancer immunotherapies. However, the key determinants and biology underpinning these tumor immune phenotypes remain elusive. Here, we provide a high-resolution dissection of the entire tumor ecosystem through single-cell RNA-sequencing analysis of 15 ovarian tumors. Immune-desert tumors are characterized by unique tumor cell-intrinsic features, including metabolic pathways and low antigen presentation, and an enrichment of monocytes and immature macrophages. Immune-infiltrated and -excluded tumors differ markedly in their T cell composition and fibroblast subsets. Furthermore, our study reveals chemokine receptor-ligand interactions within and across compartments as potential mechanisms mediating immune cell infiltration, exemplified by the tumor cell-T cell cross talk via CXCL16-CXCR6 and stromal-immune cell cross talk via CXCL12/14-CXCR4. Our data highlight potential molecular mechanisms that shape the tumor immune phenotypes and may inform therapeutic strategies to improve clinical benefit from cancer immunotherapies.
Asunto(s)
Biomarcadores de Tumor/genética , Fibroblastos/inmunología , Neoplasias Ováricas/inmunología , Análisis de la Célula Individual/métodos , Células del Estroma/inmunología , Linfocitos T/inmunología , Microambiente Tumoral , Biomarcadores de Tumor/inmunología , Quimiocina CXCL12/genética , Quimiocina CXCL12/inmunología , Quimiocina CXCL16/genética , Quimiocina CXCL16/inmunología , Quimiocinas CXC/genética , Quimiocinas CXC/inmunología , Femenino , Fibroblastos/metabolismo , Fibroblastos/patología , Humanos , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , RNA-Seq , Receptores CXCR4/genética , Receptores CXCR4/inmunología , Receptores CXCR6/genética , Receptores CXCR6/inmunología , Células del Estroma/metabolismo , Células del Estroma/patología , Linfocitos T/metabolismo , Linfocitos T/patologíaRESUMEN
The biological and medicinal impacts of proteolysis-targeting chimeras (PROTACs) and related chimeric molecules that effect intracellular degradation of target proteins via ubiquitin ligase-mediated ubiquitination continue to grow. However, these chimeric entities are relatively large compounds that often possess molecular characteristics, which may compromise oral bioavailability, solubility, and/or in vivo pharmacokinetic properties. We therefore explored the conjugation of such molecules to monoclonal antibodies using technologies originally developed for cytotoxic payloads so as to provide alternate delivery options for these novel agents. In this report, we describe the first phase of our systematic development of antibody-drug conjugates (ADCs) derived from bromodomain-containing protein 4 (BRD4)-targeting chimeric degrader entities. We demonstrate the antigen-dependent delivery of the degrader payloads to PC3-S1 prostate cancer cells along with related impacts on MYC transcription and intracellular BRD4 levels. These experiments culminate with the identification of one degrader conjugate, which exhibits antigen-dependent antiproliferation effects in LNCaP prostate cancer cells.
Asunto(s)
Proteínas de Ciclo Celular/antagonistas & inhibidores , Dipéptidos/farmacología , Compuestos Heterocíclicos con 3 Anillos/farmacología , Inmunoconjugados/farmacología , Proteolisis/efectos de los fármacos , Factores de Transcripción/antagonistas & inhibidores , Anticuerpos Monoclonales/inmunología , Antígenos de Neoplasias/inmunología , Proteínas de Ciclo Celular/metabolismo , Proliferación Celular/efectos de los fármacos , Dipéptidos/síntesis química , Dipéptidos/farmacocinética , Compuestos Heterocíclicos con 3 Anillos/síntesis química , Compuestos Heterocíclicos con 3 Anillos/farmacocinética , Humanos , Inmunoconjugados/química , Inmunoconjugados/inmunología , Oxidorreductasas/inmunología , Células PC-3 , Factores de Transcripción/metabolismo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismoRESUMEN
Heterobifunctional compounds that direct the ubiquitination of intracellular proteins in a targeted manner via co-opted ubiquitin ligases have enormous potential to transform the field of medicinal chemistry. These chimeric molecules, often termed proteolysis-targeting chimeras (PROTACs) in the chemical literature, enable the controlled degradation of specific proteins via their direction to the cellular proteasome. In this report, we describe the second phase of our research focused on exploring antibody-drug conjugates (ADCs), which incorporate BRD4-targeting chimeric degrader entities. We employ a new BRD4-binding fragment in the construction of the chimeric ADC payloads that is significantly more potent than the corresponding entity utilized in our initial studies. The resulting BRD4-degrader antibody conjugates exhibit potent and antigen-dependent BRD4 degradation and antiproliferation activities in cell-based experiments. Multiple ADCs bearing chimeric BRD4-degrader payloads also exhibit strong, antigen-dependent antitumor efficacy in mouse xenograft assessments that employ several different tumor models.
Asunto(s)
Antineoplásicos/uso terapéutico , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proliferación Celular/efectos de los fármacos , Inmunoconjugados/uso terapéutico , Neoplasias/tratamiento farmacológico , Proteolisis/efectos de los fármacos , Factores de Transcripción/antagonistas & inhibidores , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacocinética , Anticuerpos Monoclonales/uso terapéutico , Antígenos de Neoplasias/inmunología , Antineoplásicos/síntesis química , Antineoplásicos/farmacocinética , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Dipéptidos/síntesis química , Dipéptidos/farmacocinética , Dipéptidos/uso terapéutico , Femenino , Compuestos Heterocíclicos con 3 Anillos/síntesis química , Compuestos Heterocíclicos con 3 Anillos/farmacocinética , Compuestos Heterocíclicos con 3 Anillos/uso terapéutico , Humanos , Inmunoconjugados/inmunología , Inmunoconjugados/farmacocinética , Ratones SCID , Oxidorreductasas/inmunología , Factores de Transcripción/metabolismo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Inositol-Requiring Enzyme 1 (IRE1) is an essential component of the Unfolded Protein Response. IRE1 spans the endoplasmic reticulum membrane, comprising a sensory lumenal domain, and tandem kinase and endoribonuclease (RNase) cytoplasmic domains. Excess unfolded proteins in the ER lumen induce dimerization and oligomerization of IRE1, triggering kinase trans-autophosphorylation and RNase activation. Known ATP-competitive small-molecule IRE1 kinase inhibitors either allosterically disrupt or stabilize the active dimeric unit, accordingly inhibiting or stimulating RNase activity. Previous allosteric RNase activators display poor selectivity and/or weak cellular activity. In this study, we describe a class of ATP-competitive RNase activators possessing high selectivity and strong cellular activity. This class of activators binds IRE1 in the kinase front pocket, leading to a distinct conformation of the activation loop. Our findings reveal exquisitely precise interdomain regulation within IRE1, advancing the mechanistic understanding of this important enzyme and its investigation as a potential small-molecule therapeutic target.
Asunto(s)
Adenosina Trifosfato/metabolismo , Endorribonucleasas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Ribonucleasas/metabolismo , Adenosina Trifosfato/química , Sitio Alostérico/efectos de los fármacos , Cristalografía por Rayos X , Retículo Endoplásmico/metabolismo , Endorribonucleasas/química , Técnicas de Inactivación de Genes , Humanos , Ligandos , Modelos Moleculares , Fosforilación , Conformación Proteica , Pliegue de Proteína , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Multimerización de Proteína , Proteínas Serina-Treonina Quinasas/química , Ribonucleasas/química , Respuesta de Proteína DesplegadaRESUMEN
Amino-quinazoline BRaf kinase inhibitor 2 was identified from a library screen as a modest inhibitor of the unfolded protein response (UPR) regulating potential anticancer target IRE1α. A combination of crystallographic and conformational considerations were used to guide structure-based attenuation of BRaf activity and optimization of IRE1α potency. Quinazoline 6-position modifications were found to provide up to 100-fold improvement in IRE1α cellular potency but were ineffective at reducing BRaf activity. A salt bridge contact with Glu651 in IRE1α was then targeted to build in selectivity over BRaf which instead possesses a histidine in this position (His539). Torsional angle analysis revealed that the quinazoline hinge binder core was ill-suited to accommodate the required conformation to effectively reach Glu651, prompting a change to the thienopyrimidine hinge binder. Resulting analogues such as 25 demonstrated good IRE1α cellular potency and imparted more than 1000-fold decrease in BRaf activity.
RESUMEN
The ability to selectively degrade proteins with bifunctional small molecules has the potential to fundamentally alter therapy in a variety of diseases. However, the relatively large size of these chimeric molecules often results in challenging physico-chemical properties (e. g., low aqueous solubility) and poor pharmacokinetics which may complicate their inâ vivo applications. We recently discovered an exquisitely potent chimeric BET degrader (GNE-987) which exhibited picomolar cell potencies but also demonstrated low inâ vivo exposures. In an effort to improve the pharmacokinetic properties of this molecule, we discovered the first degrader-antibody conjugate by attaching GNE-987 to an anti-CLL1 antibody via a novel linker. A single IV dose of the conjugate afforded sustained inâ vivo exposures that resulted in antigen-specific tumor regressions. Enhancement of a chimeric protein degrader with poor inâ vivo properties through antibody conjugation thereby expands the utility of directed protein degradation as both a biological tool and a therapeutic possibility.
Asunto(s)
Anticuerpos Monoclonales/química , Proteínas de Ciclo Celular/metabolismo , Compuestos Heterocíclicos de 4 o más Anillos/química , Inmunoconjugados/química , Factores de Transcripción/metabolismo , Animales , Anticuerpos Monoclonales/inmunología , Proteínas de Ciclo Celular/antagonistas & inhibidores , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/química , Femenino , Semivida , Humanos , Inmunoconjugados/farmacología , Inmunoconjugados/uso terapéutico , Lectinas Tipo C/inmunología , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/patología , Ratones , Ratones SCID , Unión Proteica , Proteolisis/efectos de los fármacos , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Receptores Mitogénicos/inmunología , Resonancia por Plasmón de Superficie , Factores de Transcripción/antagonistas & inhibidores , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Multiple myeloma (MM) arises from malignant immunoglobulin (Ig)-secreting plasma cells and remains an incurable, often lethal disease despite therapeutic advances. The unfolded-protein response sensor IRE1α supports protein secretion by deploying a kinase-endoribonuclease module to activate the transcription factor XBP1s. MM cells may co-opt the IRE1α-XBP1s pathway; however, the validity of IRE1α as a potential MM therapeutic target is controversial. Genetic disruption of IRE1α or XBP1s, or pharmacologic IRE1α kinase inhibition, attenuated subcutaneous or orthometastatic growth of MM tumors in mice and augmented efficacy of two established frontline antimyeloma agents, bortezomib and lenalidomide. Mechanistically, IRE1α perturbation inhibited expression of key components of the endoplasmic reticulum-associated degradation machinery, as well as secretion of Ig light chains and of cytokines and chemokines known to promote MM growth. Selective IRE1α kinase inhibition reduced viability of CD138+ plasma cells while sparing CD138- cells derived from bone marrows of newly diagnosed or posttreatment-relapsed MM patients, in both US- and European Union-based cohorts. Effective IRE1α inhibition preserved glucose-induced insulin secretion by pancreatic microislets and viability of primary hepatocytes in vitro, as well as normal tissue homeostasis in mice. These results establish a strong rationale for developing kinase-directed inhibitors of IRE1α for MM therapy.
Asunto(s)
Endorribonucleasas/genética , Mieloma Múltiple/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/genética , Anciano , Animales , Bortezomib/farmacología , Estrés del Retículo Endoplásmico/genética , Endorribonucleasas/antagonistas & inhibidores , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Lenalidomida/farmacología , Masculino , Ratones , Persona de Mediana Edad , Mieloma Múltiple/genética , Mieloma Múltiple/patología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Respuesta de Proteína Desplegada/genética , Proteína 1 de Unión a la X-Box/genética , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND: Transient neonatal hypoglycemia occurs most commonly in newborns who are small for gestational age, large for gestational age, infants of diabetic mothers, and late preterm infants. An exact blood glucose value has not been determined for neonatal hypoglycemia, and it is important to note that poor neurologic outcomes can occur if hypoglycemia is left untreated. Interventions that separate mothers and newborns, as well as use of formula to treat hypoglycemia, have the potential to disrupt exclusive breastfeeding. PURPOSE: To determine whether implementation of a toolkit designed to support staff in the adaptation of the practice change for management of newborns at risk for hypoglycemia, that includes 40% glucose gel in an obstetric unit with a level 2 nursery will decrease admissions to the Intermediate Care Nursery, and increase exclusive breastfeeding. METHOD: This descriptive study used a retrospective chart review for pre/postimplementation of the Management of Newborns at Risk for Hypoglycemia Toolkit (Toolkit) using a convenience sample of at-risk newborns in the first 2 days of life to evaluate the proposed outcomes. RESULTS: Following implementation of the Toolkit, at-risk newborns had a clinically but not statistically significant 6.5% increase in exclusive breastfeeding and a clinically but not statistically significant 5% decrease in admissions to the Intermediate Care Nursery. IMPLICATIONS FOR PRACTICE: The Toolkit was designed for ease of staff use and to improve outcomes for the at-risk newborn. IMPLICATIONS FOR RESEARCH: Future research includes replication at other level 2 and level 1 obstetric centers and investigation into the number of 40% glucose gel doses that can safely be administered.
Asunto(s)
Glucosa/uso terapéutico , Hipoglucemia/diagnóstico , Hipoglucemia/tratamiento farmacológico , Innovación Organizacional , Algoritmos , Glucemia , Lactancia Materna , Edad Gestacional , Humanos , Recién Nacido , Enfermedades del Recién Nacido , Mejoramiento de la Calidad , Estudios Retrospectivos , Factores de Riesgo , Resultado del TratamientoRESUMEN
A novel, potent, and orally bioavailable inhibitor of the bromodomain of CBP, compound 35 (GNE-207), has been identified through SAR investigations focused on optimizing al bicyclic heteroarene to replace the aniline present in the published GNE-272 series. Compound 35â¯has excellent CBP potency (CBP IC50â¯=â¯1â¯nM, MYC EC50â¯=â¯18â¯nM), a selectively index ofâ¯>2500-fold against BRD4(1), and exhibits a good pharmacokinetic profile.
Asunto(s)
Compuestos de Bifenilo/química , Diseño de Fármacos , Factores de Transcripción p300-CBP/antagonistas & inhibidores , Animales , Sitios de Unión , Compuestos de Bifenilo/síntesis química , Compuestos de Bifenilo/metabolismo , Proteínas de Ciclo Celular , Cristalografía por Rayos X , Semivida , Humanos , Enlace de Hidrógeno , Concentración 50 Inhibidora , Ratones , Microsomas Hepáticos/metabolismo , Simulación de Dinámica Molecular , Proteínas Nucleares/antagonistas & inhibidores , Proteínas Nucleares/metabolismo , Estructura Terciaria de Proteína , Ratas , Relación Estructura-Actividad , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/metabolismo , Factores de Transcripción p300-CBP/metabolismoRESUMEN
A series of imidazo[1,2-a]pyridin-6-yl-benzamide analogs was designed as inhibitors of B-RAFV600E. Medicinal chemistry techniques were employed to explore the SAR for this series and improve selectivity versus P38 and VEGFR2.
Asunto(s)
Benzamidas/farmacología , Compuestos Heterocíclicos con 2 Anillos/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Benzamidas/síntesis química , Benzamidas/química , Relación Dosis-Respuesta a Droga , Compuestos Heterocíclicos con 2 Anillos/síntesis química , Compuestos Heterocíclicos con 2 Anillos/química , Humanos , Modelos Moleculares , Estructura Molecular , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Proteínas Proto-Oncogénicas B-raf/metabolismo , Relación Estructura-ActividadRESUMEN
The epigenetic regulator CBP/P300 presents a novel therapeutic target for oncology. Previously, we disclosed the development of potent and selective CBP bromodomain inhibitors by first identifying pharmacophores that bind the KAc region and then building into the LPF shelf. Herein, we report the "hybridization" of a variety of KAc-binding fragments with a tetrahydroquinoline scaffold that makes optimal interactions with the LPF shelf, imparting enhanced potency and selectivity to the hybridized ligand. To demonstrate the utility of our hybridization approach, two analogues containing unique Asn binders and the optimized tetrahydroquinoline moiety were rapidly optimized to yield single-digit nanomolar inhibitors of CBP with exquisite selectivity over BRD4(1) and the broader bromodomain family.
Asunto(s)
Ensayos Analíticos de Alto Rendimiento/métodos , Factores de Transcripción p300-CBP/antagonistas & inhibidores , Animales , Asparagina/química , Asparagina/metabolismo , Sitios de Unión , Proteínas de Ciclo Celular , Cristalografía por Rayos X , Femenino , Transferencia Resonante de Energía de Fluorescencia/métodos , Ratones Endogámicos , Simulación del Acoplamiento Molecular , Proteínas Nucleares/antagonistas & inhibidores , Dominios Proteicos , Pirazoles/química , Piridinas/química , Quinolinas/química , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción p300-CBP/química , Factores de Transcripción p300-CBP/metabolismoRESUMEN
Inhibition of the bromodomain of the transcriptional regulator CBP/P300 is an especially interesting new therapeutic approach in oncology. We recently disclosed in vivo chemical tool 1 (GNE-272) for the bromodomain of CBP that was moderately potent and selective over BRD4(1). In pursuit of a more potent and selective CBP inhibitor, we used structure-based design. Constraining the aniline of 1 into a tetrahydroquinoline motif maintained potency and increased selectivity 2-fold. Structure-activity relationship studies coupled with further structure-based design targeting the LPF shelf, BC loop, and KAc regions allowed us to significantly increase potency and selectivity, resulting in the identification of non-CNS penetrant 19 (GNE-781, TR-FRET IC50 = 0.94 nM, BRET IC50 = 6.2 nM; BRD4(1) IC50 = 5100 nΜ) that maintained good in vivo PK properties in multiple species. Compound 19 displays antitumor activity in an AML tumor model and was also shown to decrease Foxp3 transcript levels in a dose dependent manner.
Asunto(s)
Antineoplásicos/farmacología , Proteína de Unión a CREB/antagonistas & inhibidores , Pirazoles/farmacología , Piridinas/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacocinética , Proteína de Unión a CREB/química , Perros , Femenino , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Células HEK293 , Humanos , Macaca fascicularis , Masculino , Ratones , Dominios Proteicos , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Pirazoles/síntesis química , Pirazoles/química , Pirazoles/farmacocinética , Piridinas/síntesis química , Piridinas/química , Piridinas/farmacocinética , ARN/genética , Ratas Sprague-Dawley , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Resistance invariably develops to antiandrogen therapies used to treat newly diagnosed prostate cancers, but effective treatments for castration-resistant disease remain elusive. Here, we report that the transcriptional coactivator CBP/p300 is required to maintain the growth of castration-resistant prostate cancer. To exploit this vulnerability, we developed a novel small-molecule inhibitor of the CBP/p300 bromodomain that blocks prostate cancer growth in vitro and in vivo Molecular dissection of the consequences of drug treatment revealed a critical role for CBP/p300 in histone acetylation required for the transcriptional activity of the androgen receptor and its target gene expression. Our findings offer a preclinical proof of concept for small-molecule therapies to target the CBP/p300 bromodomain as a strategy to treat castration-resistant prostate cancer. Cancer Res; 77(20); 5564-75. ©2017 AACR.
Asunto(s)
Proteína p300 Asociada a E1A/antagonistas & inhibidores , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Bibliotecas de Moléculas Pequeñas/farmacología , Animales , Procesos de Crecimiento Celular/efectos de los fármacos , Línea Celular Tumoral , Proteína p300 Asociada a E1A/deficiencia , Proteína p300 Asociada a E1A/genética , Proteína p300 Asociada a E1A/metabolismo , Femenino , Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Masculino , Ratones , Ratones SCID , Terapia Molecular Dirigida , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/patología , Dominios Proteicos , Distribución Aleatoria , Receptores Androgénicos/metabolismo , Transducción de Señal/efectos de los fármacos , Transfección , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The single bromodomain of the closely related transcriptional regulators CBP/EP300 is a target of much recent interest in cancer and immune system regulation. A co-crystal structure of a ligand-efficient screening hit and the CBP bromodomain guided initial design targeting the LPF shelf, ZA loop, and acetylated lysine binding regions. Structure-activity relationship studies allowed us to identify a more potent analogue. Optimization of permeability and microsomal stability and subsequent improvement of mouse hepatocyte stability afforded 59 (GNE-272, TR-FRET IC50 = 0.02 µM, BRET IC50 = 0.41 µM, BRD4(1) IC50 = 13 µM) that retained the best balance of cell potency, selectivity, and in vivo PK. Compound 59 showed a marked antiproliferative effect in hematologic cancer cell lines and modulates MYC expression in vivo that corresponds with antitumor activity in an AML tumor model.
Asunto(s)
Antineoplásicos/farmacología , Descubrimiento de Drogas , Pirazoles/farmacología , Piridonas/farmacología , Factores de Transcripción p300-CBP/antagonistas & inhibidores , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Perros , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Células de Riñón Canino Madin Darby , Ratones , Ratones Desnudos , Modelos Moleculares , Estructura Molecular , Pirazoles/síntesis química , Pirazoles/química , Piridonas/síntesis química , Piridonas/química , Relación Estructura-ActividadRESUMEN
CBP and EP300 are highly homologous, bromodomain-containing transcription coactivators involved in numerous cellular pathways relevant to oncology. As part of our effort to explore the potential therapeutic implications of selectively targeting bromodomains, we set out to identify a CBP/EP300 bromodomain inhibitor that was potent both in vitro and in cellular target engagement assays and was selective over the other members of the bromodomain family. Reported here is a series of cell-potent and selective probes of the CBP/EP300 bromodomains, derived from the fragment screening hit 4-methyl-1,3,4,5-tetrahydro-2H-benzo[b][1,4]diazepin-2-one.
RESUMEN
Alterations in PI3K/AKT signaling are known to be implicated with tumorigenesis. The PI3 kinases family of lipid kinases has been an attractive therapeutic target for cancer treatment. Imidazopyridine compound 1, a potent, selective, and orally available pan-PI3K inhibitor, identified by scaffold morphing of a benzothiazole hit, was further optimized in order to achieve efficacy in a PTEN-deleted A2780 ovarian cancer mouse xenograft model. With a hypothesis that a planar conformation between the core and the 6-heteroaryl ring will allow for the accommodation of larger 5'-substituents in a hydrophobic area under P-loop, SAR efforts focused on 5'-alkoxy heteroaryl rings at the 6-position of imidazopyridine and imidazopyridazine cores that have the same dihedral angle of zero degrees. 6'-Alkoxy 5'-aminopyrazines in the imidazopyridine series were identified as the most potent compounds in the A2780 cell line. Compound 14 with 1,1,1-trifluoroisopropoxy group at 6'-position demonstrated excellent potency and selectivity, good oral exposure in rats and in vivo efficacy in A2780 tumor-bearing mouse. Also, we disclose the X-ray co-crystal structure of one enantiomer of compound 14 in PI3Kα, confirming that the trifluoromethyl group fits nicely in the hydrophobic hot spot under P-loop.
Asunto(s)
Inhibidores de las Quinasa Fosfoinosítidos-3 , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Piridinas/química , Piridinas/farmacología , Animales , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Sitios de Unión , Línea Celular Tumoral , Cristalografía por Rayos X , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Activación Enzimática/efectos de los fármacos , Femenino , Semivida , Xenoinjertos , Humanos , Ratones , Simulación del Acoplamiento Molecular , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/farmacocinética , Inhibidores de Proteínas Quinasas/uso terapéutico , Estructura Terciaria de Proteína , Piridinas/farmacocinética , Piridinas/uso terapéutico , Ratas , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
BACKGROUND: We have previously characterized several antihypertensive peptides in simulated digests of cooked eggs and showed blood pressure lowering property of fried whole egg digest. However, the long-term effects of this hydrolysate and its fractions on blood pressure are not known. Therefore, the objectives of the study were to determine the effects of long term administration of fried whole egg hydrolysate and its fractions (i.e. egg white and egg yolk) on regulation of blood pressure and associated factors in cardiovascular disease such as plasma lipid profile and tissue oxidative stress. METHODS AND RESULTS: We used spontaneously hypertensive rats (SHR), an animal model of essential hypertension. Hydrolysates of fried egg and its fractions were prepared by simulated gastro-intestinal digestion with pepsin and pancreatin. 16-17 week old male SHRs were orally administered fried whole egg hydrolysate, non-hydrolyzed fried whole egg, egg white hydrolysate or egg yolk hydrolysates (either defatted, or not) daily for 18 days. Blood pressure (BP) and heart rate were monitored by telemetry. Animals were sacrificed at the end of the treatment for vascular function studies and evaluating plasma lipid profile and tissue oxidative stress. BP was reduced by feeding fried whole egg hydrolysate but not by the non-hydrolyzed product suggesting a critical role for in vitro digestion in releasing anti-hypertensive peptides. Egg white hydrolysate and defatted egg yolk hydrolysate (but not egg yolk hydrolysate) also had similar effects. Reduction in BP was accompanied by the restoration of nitric oxide (NO) dependent vasorelaxation and reduction of plasma angiotensin II. Fried whole egg hydrolysate also reduced plasma levels of triglyceride although it was increased by the non-hydrolyzed sample. Additionally the hydrolyzed preparations attenuated tissue oxidative stress. CONCLUSION: Our results demonstrate that fried egg hydrolysates exert anti-hypertensive effects, improve plasma lipid profile and attenuate tissue oxidative stress in vivo.
Asunto(s)
Presión Sanguínea/efectos de los fármacos , Hipertensión/dietoterapia , Estrés Oxidativo/efectos de los fármacos , Hidrolisados de Proteína/administración & dosificación , Angiotensina II/sangre , Animales , Clara de Huevo , Hipertensión Esencial , Humanos , Hipertensión/sangre , Hipertensión/patología , Óxido Nítrico/metabolismo , Ratas , Ratas Endogámicas SHRRESUMEN
BACKGROUND: There is a growing interest in using functional food components as therapy for cardiovascular diseases such as hypertension. We have previously characterized a tri-peptide IRW (Ile-Arg-Trp) from egg white protein ovotransferrin; this peptide showed anti-inflammatory, anti-oxidant and angiotensin converting enzyme (ACE) inhibitor properties in vitro. Given the pathogenic roles played by angiotensin, oxidative stress and inflammation in the spontaneously hypertensive rat (SHR), we tested the therapeutic potential of IRW in this well-established model of hypertension. METHODS AND RESULTS: 16-17 week old male SHRs were orally administered IRW at either a low dose (3 mg/Kg BW) or a high dose (15 mg/Kg BW) daily for 18 days. Blood pressure (BP) and heart rate were measured by telemetry. Animals were sacrificed at the end of the treatment for vascular function studies and measuring markers of inflammation. IRW treatment attenuated mean BP by ~10 mmHg and ~40 mmHg at the low- and high-dose groups respectively compared to untreated SHRs. Heart rate was not affected. Reduction in BP was accompanied by the restoration of diurnal variations in BP, preservation of nitric oxide dependent vasorelaxation, as well as reduction of plasma angiotensin II, other inflammatory markers and tissue fibrosis. CONCLUSION: Our results demonstrate anti-hypertensive effects of IRW in vivo likely mediated through ACE inhibition, endothelial nitric oxide synthase and anti-inflammatory properties.
Asunto(s)
Antihipertensivos/uso terapéutico , Clara de Huevo/química , Hipertensión/tratamiento farmacológico , Oligopéptidos/uso terapéutico , Animales , Vasos Sanguíneos/enzimología , Western Blotting , Ritmo Circadiano , Técnica del Anticuerpo Fluorescente , Hipertensión/fisiopatología , Masculino , Óxido Nítrico/fisiología , Óxido Nítrico Sintasa de Tipo III/metabolismo , Nitrosación , Estrés Oxidativo , Ratas , Ratas Endogámicas SHR , TelemetríaRESUMEN
PI3 kinases are a family of lipid kinases mediating numerous cell processes such as proliferation, migration and differentiation. The PI3 Kinase pathway is often de-regulated in cancer through PI3Kα overexpression, gene amplification, mutations and PTEN phosphatase deletion. PI3K inhibitors represent therefore an attractive therapeutic modality for cancer treatment. Herein we describe how the potency of a benzothiazole fragment hit was quickly improved based on structural information and how this early chemotype was further optimized through scaffold hopping. This effort led to the identification of a series of 2-acetamido-5-heteroaryl imidazopyridines showing potent in vitro activity against all class I PI3Ks and attractive pharmacokinetic properties.