RESUMO
A series of potent dual JAK1/3 inhibitors have been developed from a moderately selective JAK3 inhibitor. Substitution at the C6 position of the pyrrolopyridazine core with aryl groups provided exceptional biochemical potency against JAK1 and JAK3 while maintaining good selectivity against JAK2 and Tyk2. Translation to in vivo efficacy was observed in a murine model of chronic inflammation. X-ray co-crystal structure determination confirmed the presumed inhibitor binding orientation in JAK3. Efforts to reduce hERG channel inhibition will be described.
Assuntos
Janus Quinase 1/antagonistas & inibidores , Janus Quinase 3/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Piridazinas/química , Pirróis/química , Animais , Sítios de Ligação , Domínio Catalítico , Linhagem Celular , Cristalografia por Raios X , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Meia-Vida , Humanos , Inflamação/prevenção & controle , Concentração Inibidora 50 , Janus Quinase 1/metabolismo , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 2/metabolismo , Janus Quinase 3/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Conformação Molecular , Simulação de Dinâmica Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacocinética , Piridazinas/síntese química , Piridazinas/farmacocinética , Pirróis/síntese química , Pirróis/farmacocinética , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , TYK2 Quinase/antagonistas & inibidores , TYK2 Quinase/metabolismoRESUMO
A new class of Janus kinase (JAK) inhibitors was discovered using a rationally designed pyrrolo[1,2-b]pyridazine-3-carboxamide scaffold. Preliminary studies identified (R)-(2,2-dimethylcyclopentyl)amine as a preferred C4 substituent on the pyrrolopyridazine core (3b). Incorporation of amino group to 3-position of the cyclopentane ring resulted in a series of JAK3 inhibitors (4g-4j) that potently inhibited IFNγ production in an IL2-induced whole blood assay and displayed high functional selectivity for JAK3-JAK1 pathway relative to JAK2. Further modifications led to the discovery of an orally bioavailable (2-fluoro-2-methylcyclopentyl)amino analogue 5g which is a nanomolar inhibitor of both JAK3 and TYK2, functionally selective for the JAK3-JAK1 pathway versus JAK2, and active in a human whole blood assay.
Assuntos
Descoberta de Drogas , Janus Quinase 1/antagonistas & inibidores , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 3/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Piridazinas/química , Pirróis/química , Administração Oral , Animais , Ensaio de Imunoadsorção Enzimática , Humanos , Interferon gama/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Estrutura Molecular , Conformação Proteica/efeitos dos fármacos , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacocinética , Relação Estrutura-Atividade , Distribuição TecidualRESUMO
A novel series of p38 MAP kinase inhibitors with high selectivity for the p38α isoform over the other family members including the highly homologous p38ß isoform has been identified. X-ray co-crystallographic studies have revealed an unprecedented kinase binding mode in p38α for representative analogs, 5c and 9d, in which a Leu108/Met109 peptide flip occurs within the p38α hinge region. Based on these findings, a general strategy for the rational design of additional promising p38α isoform selective inhibitors by targeting this novel binding mode is proposed.
Assuntos
Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Sítios de Ligação , Cristalografia por Raios X , Humanos , Ligação de Hidrogênio , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Simulação de Dinâmica Molecular , Ligação Proteica , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/metabolismo , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/metabolismo , Estrutura Terciária de Proteína , Relação Estrutura-AtividadeRESUMO
Pyrrolo[2,1-f][1,2,4]triazine based inhibitors of p38α have been prepared exploring functional group modifications at the C6 position. Incorporation of aryl and heteroaryl ketones at this position led to potent inhibitors with efficacy in in vivo models of acute and chronic inflammation.
Assuntos
Anti-Inflamatórios/química , Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Pirróis/química , Triazinas/química , Administração Oral , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Artrite/tratamento farmacológico , Sítios de Ligação , Cristalografia por Raios X , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Feminino , Camundongos , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Estrutura Terciária de Proteína , Ratos , Relação Estrutura-Atividade , Triazinas/farmacologia , Triazinas/uso terapêuticoRESUMO
The design, synthesis, and structure-activity relationships (SAR) of a series of 2-aminothiazol-5-yl-pyrimidines as novel p38α MAP kinase inhibitors are described. These efforts led to the identification of 41 as a potent p38α inhibitor that utilizes a unique nitrogen-sulfur intramolecular nonbonding interaction to stabilize the conformation required for binding to the p38α active site. X-ray crystallographic studies that confirm the proposed binding mode of this class of inhibitors in p38 α and provide evidence for the proposed intramolecular nitrogen-sulfur interaction are discussed.
Assuntos
Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Nitrogênio/química , Inibidores de Proteínas Quinases/síntese química , Pirimidinas/química , Enxofre/química , Tiazóis/química , Sítios de Ligação , Cristalografia por Raios X , Desenho de Fármacos , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Estrutura Terciária de Proteína , Pirimidinas/síntese química , Pirimidinas/farmacologia , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/farmacologiaRESUMO
The synthesis and structure-activity relationships (SAR) of p38α MAP kinase inhibitors based on a 5-amino-pyrazole scaffold are described. These studies led to the identification of compound 2j as a potent and selective inhibitor of p38α MAP kinase with excellent cellular potency toward the inhibition of TNFα production. Compound 2j was highly efficacious in vivo in inhibiting TNFα production in an acute murine model of TNFα production. X-ray co-crystallography of a 5-amino-pyrazole analog 2f bound to unphosphorylated p38α is also disclosed.
Assuntos
Proteína Quinase 14 Ativada por Mitógeno/química , Inibidores de Proteínas Quinases/síntese química , Pirazóis/farmacologia , Animais , Cristalografia por Raios X , Camundongos , Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Ligação Proteica , Conformação Proteica , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/síntese química , Pirazóis/química , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossínteseRESUMO
The four members of the Janus family of nonreceptor tyrosine kinases play a significant role in immune function. The JAK family kinase inhibitor, tofacitinib 1, has been approved in the United States for use in rheumatoid arthritis (RA) patients. A number of JAK inhibitors with a variety of JAK family selectivity profiles are currently in clinical trials. Our goal was to identify inhibitors that were functionally selective for JAK1 and JAK3. Compound 22 was prepared with the desired functional selectivity profile, but it suffered from poor absorption related to physical properties. Use of the phosphate prodrug 32 enabled progression to a murine collagen induced arthritis (CIA) model. The demonstration of a robust efficacy in the CIA model suggests that use of phosphate prodrugs may resolve issues with progressing this chemotype for the treatment of autoimmune diseases such as RA.
RESUMO
A novel structural class of p38 mitogen-activated protein (MAP) kinase inhibitors consisting of substituted 4-(phenylamino)-pyrrolo[2,1- f][1,2,4]triazines has been discovered. An initial subdeck screen revealed that the oxindole-pyrrolo[2,1- f][1,2,4]triazine lead 2a displayed potent enzyme inhibition (IC 50 60 nM) and was active in a cell-based TNFalpha biosynthesis inhibition assay (IC 50 210 nM). Replacement of the C4 oxindole with 2-methyl-5- N-methoxybenzamide aniline 9 gave a compound with superior p38 kinase inhibition (IC 50 10 nM) and moderately improved functional inhibition in THP-1 cells. Further replacement of the C6 ester of the pyrrolo[2,1- f][1,2,4]triazine with amides afforded compounds with increased potency, excellent oral bioavailability, and robust efficacy in a murine model of acute inflammation (murine LPS-TNFalpha). In rodent disease models of chronic inflammation, multiple compounds demonstrated significant inhibition of disease progression leading to the advancement of 2 compounds 11b and 11j into further preclinical and toxicological studies.
Assuntos
Anti-Inflamatórios não Esteroides/síntese química , Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Pirróis/síntese química , Triazinas/síntese química , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/farmacocinética , Anti-Inflamatórios não Esteroides/farmacologia , Artrite Experimental/tratamento farmacológico , Sítios de Ligação , Cristalografia por Raios X , Desenho de Fármacos , Feminino , Humanos , Técnicas In Vitro , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Microssomos Hepáticos/metabolismo , Proteína Quinase 14 Ativada por Mitógeno/química , Modelos Moleculares , Pirróis/farmacocinética , Pirróis/farmacologia , Ratos , Ratos Endogâmicos Lew , Relação Estrutura-Atividade , Triazinas/farmacocinética , Triazinas/farmacologia , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/sangueRESUMO
Rational design, synthesis, and SAR studies of a novel class of benzothiazole based inhibitors of p38alpha MAP kinase are described. The issue of metabolic instability associated with vicinal phenyl, benzo[d]thiazol-6-yl oxazoles/imidazoles was addressed by the replacement of the central oxazole or imidazole ring with an aminopyrazole system. The proposed binding mode of this new class of p38alpha inhibitors was confirmed by X-ray crystallographic studies of a representative inhibitor (6a) bound to the p38alpha enzyme.
Assuntos
Benzotiazóis/química , Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Animais , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/enzimologia , Cristalografia por Raios X , Humanos , Lipopolissacarídeos/farmacologia , Camundongos , Microssomos/efeitos dos fármacos , Microssomos/enzimologia , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacocinética , Ratos , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/metabolismoRESUMO
A novel series of compounds based on the pyrrolo[2,1-f][1,2,4]triazine ring system have been identified as potent p38 alpha MAP kinase inhibitors. The synthesis, structure-activity relationships (SAR), and in vivo activity of selected analogs from this class of inhibitors are reported. Additional studies based on X-ray co-crystallography have revealed that one of the potent inhibitors from this series binds to the DFG-out conformation of the p38 alpha enzyme.
Assuntos
Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , Pirróis/química , Triazinas/síntese química , Triazinas/farmacologia , Amidas/química , Animais , Cristalografia por Raios X , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Estrutura Molecular , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade , Triazinas/química , Fator de Necrose Tumoral alfa/biossínteseRESUMO
The synthesis and structure-activity relationships (SAR) of p38 alpha MAP kinase inhibitors based on a pyrazolo-pyrimidine scaffold are described. These studies led to the identification of compound 2x as a potent and selective inhibitor of p38 alpha MAP kinase with excellent cellular potency toward the inhibition of TNFalpha production. Compound 2x was highly efficacious in vivo in inhibiting TNFalpha production in an acute murine model of TNFalpha production. X-ray co-crystallography of a pyrazolo-pyrimidine analog 2b bound to unphosphorylated p38 alpha is also disclosed.
Assuntos
Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/química , Pirimidinas/síntese química , Pirimidinas/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Cristalografia por Raios X , Humanos , Modelos Moleculares , Estrutura Molecular , Inibidores de Proteínas Quinases/química , Pirimidinas/química , Relação Estrutura-Atividade , Proteínas Quinases p38 Ativadas por Mitógeno/químicaRESUMO
A novel structural class of p38alpha MAP kinase inhibitors has been identified via iterative SAR studies of a focused deck screen hit. Optimization of the lead series generated 6e, BMS-640994, a potent and selective p38alpha inhibitor that is orally efficacious in rodent models of acute and chronic inflammation.
Assuntos
Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Tiazóis/farmacologia , Animais , Artrite/tratamento farmacológico , Células CACO-2 , Permeabilidade da Membrana Celular/efeitos dos fármacos , Células Cultivadas , Cristalografia por Raios X , Inibidores das Enzimas do Citocromo P-450 , Sistema Enzimático do Citocromo P-450/metabolismo , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Humanos , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Microssomos Hepáticos/efeitos dos fármacos , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Estrutura Molecular , Monócitos/citologia , Monócitos/efeitos dos fármacos , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacocinética , Ratos , Ratos Endogâmicos Lew , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/farmacocinética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
PI3Kδ plays an important role controlling immune cell function and has therefore been identified as a potential target for the treatment of immunological disorders. This article highlights our work toward the identification of a potent, selective, and efficacious PI3Kδ inhibitor. Through careful SAR, the successful replacement of a polar pyrazole group by a simple chloro or trifluoromethyl group led to improved Caco-2 permeability, reduced Caco-2 efflux, reduced hERG PC activity, and increased selectivity profile while maintaining potency in the CD69 hWB assay. The optimization of the aryl substitution then identified a 4'-CN group that improved the human/rodent correlation in microsomal metabolic stability. Our lead molecule is very potent in PK/PD assays and highly efficacious in a mouse collagen-induced arthritis model.
Assuntos
Artrite Experimental/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Relação Estrutura-Atividade , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Células CACO-2/efeitos dos fármacos , Células CACO-2/imunologia , Cães , Canal de Potássio ERG1/metabolismo , Inibidores Enzimáticos/química , Feminino , Humanos , Doenças do Sistema Imunitário/tratamento farmacológico , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Lectinas Tipo C/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Pirazóis/química , Pirazóis/metabolismo , Pirazóis/farmacologia , CoelhosRESUMO
Oral agents targeting Janus-associated kinases (JAKs) are promising new agents in clinical development. To better understand the relationship between JAK inhibition and biological outcome, compounds targeting JAKs were evaluated in peripheral human whole blood. To date, these analyses are low throughput and costly. Here, we developed a robust 384-well, high-throughput flow-based assay approach to screen small molecules for JAK/STAT signaling inhibition in human whole blood. This assay platform provides a highly sensitive analysis of signaling events in blood and facilitates measurement of target engagement. Further, the automation technologies and process optimizations developed here overcame sample integrity, handling, and multiparametric data analysis bottlenecks without affecting assay performance. Together these efforts dramatically increased sample throughput compared to conventional manual flow cytometric approaches and enabled development of novel JAK/STAT inhibitors.
Assuntos
Citometria de Fluxo/métodos , Ensaios de Triagem em Larga Escala/métodos , Inibidores de Proteínas Quinases/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , Humanos , Janus Quinases/antagonistas & inibidores , Janus Quinases/genética , Fosforilação , Inibidores de Proteínas Quinases/química , Fatores de Transcrição STAT/antagonistas & inibidores , Fatores de Transcrição STAT/genética , Bibliotecas de Moléculas Pequenas/químicaRESUMO
A novel class of 5-cyanopyrimidine-based inhibitors of p38alpha MAP kinase has been investigated. Analogues optimized through SAR iterations display low nanomolar enzymatic and cellular activity. The in vivo efficacy of this class of p38 inhibitors was demonstrated by 3a and 3b (>50% reduction in TNF levels when orally dosed at 5 mg/kg, 5 h prior to LPS administration in an acute murine model of inflammation). For 3a and 3b, the previously identified N-methoxybenzamide moiety (1) was replaced with N-(isoxazol-3-yl)benzamide, thereby providing increased metabolic stability. Cyanopyrimidine 3a demonstrated 100% oral bioavailability in mouse. High p38 kinase selectivity versus over 20 kinases was observed for analogue 3b. Direct hydrogen bonding of the cyano nitrogen of the 5-cyanopyrimidine core to the backbone NH of Met109 was confirmed by X-ray crystallographic analysis of 3a bound to p38alpha.
Assuntos
Anti-Inflamatórios não Esteroides/síntese química , Benzamidas/síntese química , Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Nitrilas/síntese química , Pirimidinas/síntese química , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Benzamidas/química , Benzamidas/farmacologia , Disponibilidade Biológica , Células Cultivadas , Cristalografia por Raios X , Feminino , Humanos , Técnicas In Vitro , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Proteína Quinase 14 Ativada por Mitógeno/química , Modelos Moleculares , Nitrilas/química , Nitrilas/farmacologia , Pirimidinas/química , Pirimidinas/farmacologia , Ratos , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/biossínteseRESUMO
A new structural class of triaminotriazine aniline amides possessing potent p38 enzyme activity has been discovered. The initial hit (compound 1a) was identified through screening the Pharmacopeia ECLiPS compound collection. SAR modification led to the identification of a short acting triaminotriazine aniline methoxyamide (compound 1m) possessing in vitro and in vivo oral activity in animal models of acute and chronic inflammatory disease. An X-ray crystal structure of compound 1m in this class, cocrystallized with unactivated p38 alpha protein, indicates that these compounds bind to the ATP binding pocket and possess key H-bonding interactions within a deeper cleft. Hydrogen bonding between one of the triazine nitrogens and the backbone NH of the Met109 residue occurs through a water molecule. The methoxyamide NH and carbonyl oxygen are within H-bonding distance of Glu71 and Asp168.
Assuntos
Amidas/síntese química , Compostos de Anilina/síntese química , Anti-Inflamatórios não Esteroides/síntese química , Benzamidas/síntese química , Triazinas/síntese química , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Administração Oral , Amidas/química , Amidas/farmacologia , Compostos de Anilina/química , Compostos de Anilina/farmacologia , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Benzamidas/química , Benzamidas/farmacologia , Cristalografia por Raios X , Feminino , Humanos , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos BALB C , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Modelos Moleculares , Estrutura Molecular , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Ratos , Ratos Endogâmicos Lew , Relação Estrutura-Atividade , Triazinas/química , Triazinas/farmacologia , Fator de Necrose Tumoral alfa/biossíntese , Proteínas Quinases p38 Ativadas por Mitógeno/químicaRESUMO
The discovery and characterization of 7k (BMS-582949), a highly selective p38α MAP kinase inhibitor that is currently in phase II clinical trials for the treatment of rheumatoid arthritis, is described. A key to the discovery was the rational substitution of N-cyclopropyl for N-methoxy in 1a, a previously reported clinical candidate p38α inhibitor. Unlike alkyl and other cycloalkyls, the sp(2) character of the cyclopropyl group can confer improved H-bonding characteristics to the directly substituted amide NH. Inhibitor 7k is slightly less active than 1a in the p38α enzymatic assay but displays a superior pharmacokinetic profile and, as such, was more effective in both the acute murine model of inflammation and pseudoestablished rat AA model. The binding mode of 7k with p38α was confirmed by X-ray crystallographic analysis.
Assuntos
Anti-Inflamatórios não Esteroides/síntese química , Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Pirróis/síntese química , Triazinas/síntese química , Animais , Anti-Inflamatórios não Esteroides/farmacocinética , Anti-Inflamatórios não Esteroides/farmacologia , Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Disponibilidade Biológica , Células CACO-2 , Cristalografia por Raios X , Feminino , Humanos , Ligação de Hidrogênio , Técnicas In Vitro , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Microssomos Hepáticos/metabolismo , Proteína Quinase 14 Ativada por Mitógeno/química , Modelos Moleculares , Conformação Molecular , Ligação Proteica , Pirróis/farmacocinética , Pirróis/farmacologia , Ratos , Ratos Endogâmicos Lew , Ratos Sprague-Dawley , Estereoisomerismo , Relação Estrutura-Atividade , Triazinas/farmacocinética , Triazinas/farmacologia , Fator de Necrose Tumoral alfa/biossínteseRESUMO
Dasatinib is an oral small molecule inhibitor of Abl and Src family tyrosine kinases (SFK), including p56(Lck) (Lck). Given the central importance of Lck in transmitting signals from the T-cell receptor (TCR) signaling complex and the potent ability of dasatinib to inhibit Lck activity, we hypothesized this agent could provide a novel route of immunomodulation via targeted inhibition of antigen-induced signaling. Herein, we show that dasatinib inhibits TCR-mediated signal transduction, cellular proliferation, cytokine production, and in vivo T-cell responses. However, dasatinib-mediated inhibition does not induce apoptosis because the effect is reversible or may be overcome by signals bypassing the TCR, such as phorbol ester. Signal transduction and proliferative responses via IL-2 remain essentially unperturbed, suggesting that dasatinib displays specificity for TCR signaling. In addition, dasatinib combined with cyclosporine A or rapamycin led to a much more potent inhibition of T-cell activation, suggesting that targeted inhibition of Lck could be a useful adjunct for enhanced immunomodulation. In combination with currently available immunomodulatory agents, SFK inhibition could potentially increase immunomodulatory efficacy while minimizing toxicity of individual agents.
Assuntos
Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirimidinas/farmacologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Tiazóis/farmacologia , Animais , Biomarcadores , Antígenos CD28/imunologia , Complexo CD3/imunologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ciclosporina/farmacologia , Citocinas/biossíntese , Dasatinibe , Humanos , Masculino , Camundongos , Ligação Proteica , Proteínas Tirosina Quinases/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Sirolimo/farmacologia , Linfócitos T/enzimologiaRESUMO
A series of substituted 2-(aminoheteroaryl)-thiazole-5-carboxamide analogs have been synthesized as novel, potent inhibitors of the Src-family kinase p56Lck. Among them, compound 2 displayed superior in vitro potency and excellent in vivo efficacy.