RESUMO
Inhibition of the bromodomain and extra-terminal (BET) family of adaptor proteins is an attractive strategy for targeting transcriptional regulation of key oncogenes, such as c-MYC. Starting with the screening hit 1, a combination of structure-activity relationship and protein structure-guided drug design led to the discovery of a differently oriented carbazole 9 with favorable binding to the tryptophan, proline, and phenylalanine (WPF) shelf conserved in the BET family. Identification of an additional lipophilic pocket and functional group optimization to optimize pharmacokinetic (PK) properties culminated in the discovery of 18 (BMS-986158) with excellent potency in binding and functional assays. On the basis of its favorable PK profile and robust in vivo activity in a panel of hematologic and solid tumor models, BMS-986158 was selected as a candidate for clinical evaluation.
Assuntos
Antineoplásicos/farmacologia , Carbazóis/farmacologia , Descoberta de Drogas , Fenilalanina/farmacologia , Prolina/farmacologia , Triptofano/farmacologia , Administração Oral , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Carbazóis/administração & dosagem , Carbazóis/química , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/metabolismo , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Fenilalanina/administração & dosagem , Fenilalanina/química , Prolina/administração & dosagem , Prolina/química , Relação Estrutura-Atividade , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Triptofano/administração & dosagem , Triptofano/químicaRESUMO
Structure-activity relationships in a series of (2-oxo-1,4-benzodiazepin-3-yl)-succinamides identified highly potent inhibitors of γ-secretase mediated signaling of Notch1/2/3/4 receptors. On the basis of its robust in vivo efficacy at tolerated doses in Notch driven leukemia and solid tumor xenograft models, 12 (BMS-906024) was selected as a candidate for clinical evaluation.
RESUMO
This Letter describes synthesis, SAR, and biological activity of (2-oxo-1,4-benzodiazepin-3-yl)-succinamides as inhibitors of γ-secretase mediated signaling of Notch receptors. Optimization of this series led to the identification of BMS-871 (compound 30) which displayed robust in vivo efficacy in Notch-dependent leukemia and solid tumor xenograft models.
Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Benzodiazepinonas/administração & dosagem , Benzodiazepinonas/farmacologia , Receptores Notch/antagonistas & inibidores , Administração Oral , Animais , Antineoplásicos/química , Benzodiazepinonas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Receptores Notch/metabolismo , Relação Estrutura-AtividadeRESUMO
PURPOSE: Angiogenesis is a critical step in the establishment, growth, and metastasis of solid tumors, and combination of antiangiogenic agents with chemotherapy is an attractive therapeutic option. We investigated the potential of ixabepilone, the first in a new class of antineoplastic agents known as epothilones, to synergize with antiangiogenic agents to inhibit tumor growth. EXPERIMENTAL DESIGN: In vitro and in vivo cytotoxicity of ixabepilone as single agent and in combination with two targeted antiangiogenic agents, bevacizumab or sunitinib, were examined in preclinical tumor models. Direct effects of the agents against endothelial cells was also examined and compared with the effects of paclitaxel as single agent and in combination with bevacizumab. RESULTS: Ixabepilone showed robust synergistic antitumor activity in combination with bevacizumab and sunitinib in preclinical in vivo models derived from breast, colon, lung, and kidney cancers. The synergistic antitumor effect was greater with ixabepilone compared with paclitaxel. Furthermore, ixabepilone was more effective than paclitaxel at killing endothelial cells expressing P-glycoprotein in vitro and inhibiting endothelial cell proliferation and tumor angiogenesis in vivo. CONCLUSIONS: Ixabepilone may enhance the antitumor effects of antiangiogenic therapy by direct cytotoxicity and also indirectly via the killing of tumor-associated endothelial cells. Given that ixabepilone has reduced susceptibility to drug efflux pumps compared with taxanes, these data may explain the increased antiangiogenic and antitumor activity of ixabepilone in combination with antiangiogenic agents. Phase II studies to assess the efficacy and safety of ixabepilone plus bevacizumab in locally recurrent or metastatic breast cancer are planned.
Assuntos
Inibidores da Angiogênese/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Antineoplásicos/administração & dosagem , Epotilonas/administração & dosagem , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/análise , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Bevacizumab , Sinergismo Farmacológico , Células Endoteliais/efeitos dos fármacos , Epotilonas/farmacologia , Feminino , Humanos , Indóis/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Pirróis/administração & dosagem , Sunitinibe , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
PURPOSE: Dasatinib (BMS-354825) is a potent, oral multi-targeted kinase inhibitor. It is an effective therapy for patients with imatinib-resistant or -intolerant Ph+ leukemias,. It has demonstrated promising preclinical anti-tumor activity, and is under clinical evaluation in solid tumors. To support the clinical development of dasatinib, we identified a pharmacodynamic biomarker to assess in vivo SRC kinase inhibition, with subsequent evaluation in cancer patients. METHODS: The biomarker, phosphorylated SRC (phospho-SRC), was first identified in human prostate PC-3 tumor cells and peripheral blood mononuclear cells (PBMCs) in vitro. It was further assessed in nude mice bearing PC-3 xenografts. Phospho-SRC[pY418] in tumors and PBMC were measured by western blot analysis, and were quantified by ELISA assays. Dasatinib plasma concentrations were determined using LC/MS/MS. RESULTS: In PC-3 cells, dasatinib showed dose-dependent anti-proliferative effect, which correlated with the inhibition of phospho-SRC[pY418] and of SRC kinase activity. With a single oral dose of 50 or 15 mg/kg, tumoral phospho-SRC[pY418] was maximally inhibited at 3 h, partially reversed between 7 and 17 h, and completely recovered after 24 h post dose. At 5 mg/kg, tumoral phospho-SRC[pY418] inhibition was less pronounced and recovered more rapidly to baseline level within 24h. Dasatinib (1 mg/kg) resulted in little inhibition. In PBMCs, a similar time course and extent of phospho-SRC[pY418] inhibition was observed. Inhibition of phospho-SRC[pY418] in vivo appeared to correlate with the preclinical in vivo efficacy and PK profiles of dasatinib in mice. CONCLUSIONS: Phospho-SRC[pY418] may potentially be used as a biomarker to enable assessment of target inhibition in clinical studies exploring dasatinib antitumor activity.
Assuntos
Adenocarcinoma/patologia , Antineoplásicos/farmacologia , Monitoramento de Medicamentos/métodos , Proteínas de Neoplasias/antagonistas & inibidores , Neoplasias da Próstata/patologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Tiazóis/farmacologia , Quinases da Família src/análise , Adenocarcinoma/química , Adenocarcinoma/tratamento farmacológico , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Biomarcadores , Divisão Celular/efeitos dos fármacos , Dasatinibe , Feminino , Humanos , Leucócitos Mononucleares/química , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Camundongos , Camundongos Nus , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/sangue , Fosfoproteínas/antagonistas & inibidores , Fosforilação , Neoplasias da Próstata/química , Neoplasias da Próstata/tratamento farmacológico , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/administração & dosagem , Pirimidinas/farmacocinética , Pirimidinas/uso terapêutico , Organismos Livres de Patógenos Específicos , Especificidade por Substrato , Tiazóis/administração & dosagem , Tiazóis/farmacocinética , Tiazóis/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , Quinases da Família src/antagonistas & inibidores , Quinases da Família src/sangueRESUMO
PURPOSE: Chronic myeloid leukemia (CML) is caused by reciprocal translocation between chromosomes 9 and 22, forming BCR-ABL, a constitutively activated tyrosine kinase. Imatinib mesylate, a selective inhibitor of BCR-ABL, represents current frontline therapy for CML; however, emerging evidence suggests that drug resistance to imatinib may limit its long-term success. To improve treatment options, dasatinib (BMS-354825) was developed as a novel, oral, multi-targeted kinase inhibitor of BCR-ABL and SRC family kinases. To date, dasatinib has shown promising anti-leukemic activity in preclinical models of CML and in phase I/II clinical studies in patients with imatinib-resistant or imatinib-intolerant disease. EXPERIMENTAL DESIGN: The pharmacokinetic and pharmacodynamic biomarkers of dasatinib were investigated in K562 human CML xenografts grown s.c. in severe combined immunodeficient mice. Tumoral levels of phospho-BCR-ABL/phospho-CrkL were determined by Western blot. RESULTS: Following a single oral administration of dasatinib at a preclinical efficacious dose of 1.25 or 2.5 mg/kg, tumoral phospho-BCR-ABL/phospho-CrkL were maximally inhibited at approximately 3 hours and recovered to basal levels by 24 hours. The time course and extent of the inhibition correlated with the plasma levels of dasatinib in mice. Pharmacokinetic/biomarker modeling predicted that the plasma concentration of dasatinib required to inhibit 90% of phospho-BCR-ABL in vivo was 10.9 ng/mL in mice and 14.6 ng/mL in humans, which is within the range of concentrations achieved in CML patients who responded to dasatinib treatment in the clinic. CONCLUSIONS: Phospho-BCR-ABL/phospho-CrkL are likely to be useful clinical biomarkers for the assessment of BCR-ABL kinase inhibition by dasatinib.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Antineoplásicos/farmacocinética , Biomarcadores Tumorais/antagonistas & inibidores , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Proteínas Nucleares/antagonistas & inibidores , Pirimidinas/farmacocinética , Tiazóis/farmacocinética , Proteínas Adaptadoras de Transdução de Sinal/análise , Administração Oral , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/sangue , Biomarcadores Tumorais/análise , Western Blotting , Linhagem Celular Tumoral , Dasatinibe , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Proteínas de Fusão bcr-abl/análise , Humanos , Injeções Intravenosas , Camundongos , Camundongos SCID , Proteínas Nucleares/análise , Valor Preditivo dos Testes , Pirimidinas/administração & dosagem , Pirimidinas/sangue , Relação Estrutura-Atividade , Tiazóis/administração & dosagem , Tiazóis/sangue , Fatores de Tempo , Transplante Heterólogo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Receptor tyrosine kinases (RTK) remain an area of therapeutic interest because of their role in epithelial tumors, and experimental models specific to these targets are highly desirable. Chimeric receptors were prepared by in-frame fusion of the CD8 extracellular sequence with the cytoplasmic sequences of RTKs. A CD8HER2 fusion protein was shown to form disulfide-mediated homodimers and to transform fibroblasts and epithelial cells. CD8RTK fusion proteins transform rat kidney epithelial cells and impart phenotypes that may reflect signaling specificity inherent in the native receptors. Transgenic expression of CD8HER2 and CD8Met in mice resulted in the formation of salivary and mammary gland tumors. The transgenic tumors allow the derivation of allograft tumors and cell lines that are sensitive to inhibition by small molecule kinase inhibitors. This approach provides excellent cell and tumor models for the characterization of signaling properties of diverse RTKs and for the evaluation of rationally designed antagonists targeting these kinases.
Assuntos
Antígenos CD8/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Neoplasias Mamárias Animais/genética , Receptor ErbB-2/metabolismo , Proteínas Recombinantes de Fusão/genética , Neoplasias das Glândulas Salivares/genética , Animais , Western Blotting , Transformação Celular Neoplásica/genética , Dimerização , Modelos Animais de Doenças , Dissulfetos/farmacologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Neoplasias Mamárias Animais/tratamento farmacológico , Neoplasias Mamárias Animais/etiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Camundongos Transgênicos , Fragmentos de Peptídeos/imunologia , Plasmídeos , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Ratos , Receptores Proteína Tirosina Quinases/metabolismo , Neoplasias das Glândulas Salivares/tratamento farmacológico , Neoplasias das Glândulas Salivares/etiologia , TransfecçãoRESUMO
The insulin-like growth factor I receptor (IGF-IR) is a transmembrane tyrosine kinase that is essential to growth and development and also thought to provide a survival signal for the maintenance of the transformed phenotype. There has been increasing interest in further understanding the role of IGF-I signaling in cancer and in developing receptor antagonists for therapeutic application. We describe herein a novel animal model that involves transgenic expression of a fusion receptor that is constitutively activated by homodimerization. Transgenic mice that expressed the activated receptor showed aberrant development of the mammary glands and developed salivary and mammary adenocarcinomas as early as 8 weeks of age. Xenograft tumors and a cell line were derived from the transgenic animals and are sensitive to inhibition by a novel small-molecule inhibitor of the IGF-IR kinase. This new model should provide new opportunities for further understanding how aberrant IGF-IR signaling leads to tumorigenesis and for optimizing novel antagonists of the receptor kinase.
Assuntos
Adenocarcinoma/genética , Transformação Celular Neoplásica/genética , Neoplasias Mamárias Experimentais/genética , Receptor IGF Tipo 1/biossíntese , Neoplasias das Glândulas Salivares/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Antígenos CD8/biossíntese , Antígenos CD8/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Feminino , Humanos , Neoplasias Mamárias Experimentais/enzimologia , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Camundongos Nus , Camundongos Transgênicos , Transplante de Neoplasias , Gravidez , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor IGF Tipo 1/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Neoplasias das Glândulas Salivares/enzimologia , Neoplasias das Glândulas Salivares/patologia , Transfecção , Transgenes/genética , Transplante HeterólogoRESUMO
A series of substituted 2-(aminopyridyl)- and 2-(aminopyrimidinyl)thiazole-5-carboxamides was identified as potent Src/Abl kinase inhibitors with excellent antiproliferative activity against hematological and solid tumor cell lines. Compound 13 was orally active in a K562 xenograft model of chronic myelogenous leukemia (CML), demonstrating complete tumor regressions and low toxicity at multiple dose levels. On the basis of its robust in vivo activity and favorable pharmacokinetic profile, 13 was selected for additional characterization for oncology indications.
Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Proteínas Proto-Oncogênicas c-abl/antagonistas & inibidores , Pirimidinas/farmacologia , Tiazóis/farmacologia , Quinases da Família src/antagonistas & inibidores , Trifosfato de Adenosina/metabolismo , Animais , Dasatinibe , Humanos , Células K562 , Camundongos , Proteínas Proto-Oncogênicas c-abl/química , Pirimidinas/farmacocinética , Ratos , Ratos Sprague-Dawley , Tiazóis/farmacocinética , Quinases da Família src/químicaRESUMO
BMS-214662 and BMS-225975 are tetrahydrobenzodiazepine-based farnesyltransferase inhibitors (FTIs) that have nearly identical structures and very similar pharmacological profiles associated with farnesyltransferase (FT) inhibition. Despite their similar activity against FT in vitro and in cells, these compounds differ dramatically in their apoptotic potency and tumor-regressing activity in vivo. BMS-214662 is the most potent apoptotic FTI known and exhibits curative responses in mice bearing a variety of staged human tumor xenografts such as HCT-116 human colon tumor. By contrast, BMS-225975 does not cause tumor regression and at best causes partial tumor growth inhibition in staged HCT-116 human colon tumor xenografts. Lack of tumor regression activity in BMS-225975 was attributable to its relatively weak apoptotic potency, not to poor cell permeability or pharmacokinetics. Both compounds were equally effective in inhibiting Ras processing and causing accumulation of a variety of nonfarnesylated substrates of FT in HCT-116 cells. Because BMS-225975 has poor apoptotic activity compared with BMS-214662 but inhibits FT to the same extent as BMS-214662, it is very unlikely that FT inhibition alone can account for the apoptotic potency of BMS-214662. Clearly distinct patterns of sensitivities in a cell line panel were obtained for the apoptotic FTI BMS-214662 and the cytostatic FTI BMS-225975. Activation of the c-Jun-NH(2)-terminal kinase pathway was readily observed with BMS-214662 but not with BMS-225975. We developed a highly sensitive San-1 murine xenograft tumor model that is particularly useful for evaluating the in vivo activity of cytostatic FTIs such as BMS-225975.