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1.
Clin Cancer Res ; 22(22): 5527-5538, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27780853

RESUMO

PURPOSE: Non-small cell lung cancers (NSCLCs) harboring ALK gene rearrangements (ALK+) typically become resistant to the first-generation anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitor (TKI) crizotinib through development of secondary resistance mutations in ALK or disease progression in the brain. Mutations that confer resistance to second-generation ALK TKIs ceritinib and alectinib have also been identified. Here, we report the structure and first comprehensive preclinical evaluation of the next-generation ALK TKI brigatinib. EXPERIMENTAL DESIGN: A kinase screen was performed to evaluate the selectivity profile of brigatinib. The cellular and in vivo activities of ALK TKIs were compared using engineered and cancer-derived cell lines. The brigatinib-ALK co-structure was determined. RESULTS: Brigatinib potently inhibits ALK and ROS1, with a high degree of selectivity over more than 250 kinases. Across a panel of ALK+ cell lines, brigatinib inhibited native ALK (IC50, 10 nmol/L) with 12-fold greater potency than crizotinib. Superior efficacy of brigatinib was also observed in mice with ALK+ tumors implanted subcutaneously or intracranially. Brigatinib maintained substantial activity against all 17 secondary ALK mutants tested in cellular assays and exhibited a superior inhibitory profile compared with crizotinib, ceritinib, and alectinib at clinically achievable concentrations. Brigatinib was the only TKI to maintain substantial activity against the most recalcitrant ALK resistance mutation, G1202R. The unique, potent, and pan-ALK mutant activity of brigatinib could be rationalized by structural analyses. CONCLUSIONS: Brigatinib is a highly potent and selective ALK inhibitor. These findings provide the molecular basis for the promising activity being observed in ALK+, crizotinib-resistant patients with NSCLC being treated with brigatinib in clinical trials. Clin Cancer Res; 22(22); 5527-38. ©2016 AACR.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Compostos Organofosforados/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Quinase do Linfoma Anaplásico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Crizotinibe , Células Hep G2 , Humanos , Neoplasias Pulmonares/metabolismo , Mutação/efeitos dos fármacos , Pirazóis/farmacologia , Piridinas/farmacologia , Sulfonas/farmacologia , Células U937
2.
J Med Chem ; 59(10): 4948-64, 2016 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-27144831

RESUMO

In the treatment of echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase positive (ALK+) non-small-cell lung cancer (NSCLC), secondary mutations within the ALK kinase domain have emerged as a major resistance mechanism to both first- and second-generation ALK inhibitors. This report describes the design and synthesis of a series of 2,4-diarylaminopyrimidine-based potent and selective ALK inhibitors culminating in identification of the investigational clinical candidate brigatinib. A unique structural feature of brigatinib is a phosphine oxide, an overlooked but novel hydrogen-bond acceptor that drives potency and selectivity in addition to favorable ADME properties. Brigatinib displayed low nanomolar IC50s against native ALK and all tested clinically relevant ALK mutants in both enzyme-based biochemical and cell-based viability assays and demonstrated efficacy in multiple ALK+ xenografts in mice, including Karpas-299 (anaplastic large-cell lymphomas [ALCL]) and H3122 (NSCLC). Brigatinib represents the most clinically advanced phosphine oxide-containing drug candidate to date and is currently being evaluated in a global phase 2 registration trial.


Assuntos
Antineoplásicos/farmacologia , Descoberta de Drogas , Neoplasias Pulmonares/tratamento farmacológico , Compostos Organofosforados/farmacologia , Fosfinas/química , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Administração Oral , Quinase do Linfoma Anaplásico , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia , Camundongos , Camundongos SCID , Conformação Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Compostos Organofosforados/administração & dosagem , Compostos Organofosforados/química , Fosfinas/farmacologia , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/química , Pirimidinas/administração & dosagem , Pirimidinas/química , Ratos , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Relação Estrutura-Atividade
3.
Cancer Chemother Pharmacol ; 71(5): 1315-23, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23468082

RESUMO

PURPOSE: Activating mutations in FGFR2 have been identified as potential therapeutic targets in endometrial cancer, typically occurring alongside genetic alterations that disrupt the mTOR pathway, such as PTEN loss. These observations suggest that the mTOR pathway may act in concert with oncogenic FGFR2 to drive endometrial cancer growth in a subset of patients. The aim of this study was to examine the therapeutic potential of a rational drug combination based on the simultaneous targeting of mutant-FGFR2 and mTOR-driven signaling pathways in endometrial cancer cells. METHODS: Ponatinib is an oral multitargeted kinase inhibitor that potently inhibits all 4 members of the FGFR family. Ridaforolimus is a selective inhibitor of mTOR that has demonstrated positive clinical activity in endometrial cancer. The combinatorial effects of ponatinib and ridaforolimus on growth of endometrial cancer models, and their modes of action, were evaluated in vitro and in vivo. RESULTS: The combination of ponatinib and ridaforolimus had a synergistic effect on the in vitro growth of endometrial lines bearing an activating FGFR2 mutation, irrespective of PTEN status. Concomitant inhibition of both FGFR2 and mTOR signaling pathways was observed, with simultaneous blockade resulting in enhanced cell cycle arrest. Ponatinib and ridaforolimus each demonstrated inhibition of tumor growth in vivo, but dual inhibition by the combination of agents resulted in superior efficacy and induced tumor regression in an endometrial xenograft. CONCLUSIONS: These encouraging preclinical findings suggest the inhibition of both FGFR2 and mTOR by the ponatinib-ridaforolimus combination may provide a new therapeutic strategy to treat advanced endometrial cancers with dual pathway dysregulation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias do Endométrio/tratamento farmacológico , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Serina-Treonina Quinases TOR/antagonistas & inibidores , Animais , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sinergismo Farmacológico , Neoplasias do Endométrio/patologia , Feminino , Humanos , Imidazóis/administração & dosagem , Camundongos , Camundongos Nus , Terapia de Alvo Molecular , Mutação , Inibidores de Proteínas Quinases/farmacologia , Piridazinas/administração & dosagem , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Transdução de Sinais/efeitos dos fármacos , Sirolimo/administração & dosagem , Sirolimo/análogos & derivados , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Mol Cancer Ther ; 11(3): 690-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22238366

RESUMO

Members of the fibroblast growth factor receptor family of kinases (FGFR1-4) are dysregulated in multiple cancers. Ponatinib (AP24534) is an oral multitargeted tyrosine kinase inhibitor being explored in a pivotal phase II trial in patients with chronic myelogenous leukemia due to its potent activity against BCR-ABL. Ponatinib has also been shown to inhibit the in vitro kinase activity of all four FGFRs, prompting us to examine its potential as an FGFR inhibitor. In Ba/F3 cells engineered to express activated FGFR1-4, ponatinib potently inhibited FGFR-mediated signaling and viability with IC(50) values <40 nmol/L, with substantial selectivity over parental Ba/F3 cells. In a panel of 14 cell lines representing multiple tumor types (endometrial, bladder, gastric, breast, lung, and colon) and containing FGFRs dysregulated by a variety of mechanisms, ponatinib inhibited FGFR-mediated signaling with IC(50) values <40 nmol/L and inhibited cell growth with GI(50) (concentration needed to reduce the growth of treated cells to half that of untreated cells) values of 7 to 181 nmol/L. Daily oral dosing of ponatinib (10-30 mg/kg) to mice reduced tumor growth and inhibited signaling in all three tumor models examined. Importantly, the potency of ponatinib in these models is similar to that previously observed in BCR-ABL-driven models and plasma levels of ponatinib that exceed the IC(50) values for FGFR1-4 inhibition can be sustained in patients. These results show that ponatinib is a potent pan-FGFR inhibitor and provide strong rationale for its evaluation in patients with FGFR-driven cancers.


Assuntos
Imidazóis/farmacologia , Neoplasias/tratamento farmacológico , Piridazinas/farmacologia , Receptores de Fatores de Crescimento de Fibroblastos/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Amplificação de Genes , Humanos , Immunoblotting , Camundongos , Camundongos SCID , Mutação , Neoplasias/metabolismo , Neoplasias/patologia , Fosforilação/efeitos dos fármacos , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptores de Fatores de Crescimento de Fibroblastos/genética , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo
5.
J Antibiot (Tokyo) ; 64(9): 649-54, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21792211

RESUMO

We describe the identification of novel rapamycin derivatives present as low-level impurities in active pharmaceutical ingredients using an integrated, multidisciplinary approach. Rapamycin, a fermentation-derived natural product is itself used clinically and provides the starting material for several rapamycin analog drugs, typically used in oncology. LC-MS proved a sensitive means to analyze impurity profiles in batches of rapamycin. MS fragmentation was used to gain structural insight into these impurities, usually fermentation by-products, structurally very similar to rapamycin. In cases where MS fragmentation was unable to provide unambiguous structural identification, the impurities were isolated and purified using orthogonal HPLC methods. Using the higher mass sensitivity of small-volume NMR microprobes, submilligram amounts of isolated impurities were sufficient for further characterization by multidimensional NMR spectroscopy. Full assignment of the (1)H and (13)C NMR signals revealed the structure of these impurities at an atomic level. This systematic workflow enabled the identification of several novel rapamycin congeners from active pharmaceutical ingredient without the need for large-scale isolation of impurities. For illustration, two novel rapamycin derivatives are described in this study: 12-ethyl-rapamycin and 33-ethyl-rapamycin, which exemplify previously unreported modifications on the carbon skeleton of the rapamycin macrocycle. The methodologies described here can be of wide use for identification of closely related structures found; for example as fermentation by-products, metabolites or degradants of natural product-based drugs.


Assuntos
Cromatografia Líquida/métodos , Contaminação de Medicamentos , Preparações Farmacêuticas/química , Sirolimo/química , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Espectroscopia de Ressonância Magnética , Preparações Farmacêuticas/análise , Sirolimo/isolamento & purificação
6.
Chem Biol Drug Des ; 78(6): 999-1005, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22034911

RESUMO

Activating gene rearrangements of anaplastic lymphoma kinase (ALK) have been identified as driver mutations in non-small-cell lung cancer, inflammatory myofibroblastic tumors, and other cancers. Crizotinib, a dual MET/ALK inhibitor, has demonstrated promising clinical activity in patients with non-small-cell lung cancer and inflammatory myofibroblastic tumors harboring ALK translocations. Inhibitors of driver kinases often elicit kinase domain mutations that confer resistance, and such mutations have been successfully predicted using in vitro mutagenesis screens. Here, this approach was used to discover an extensive set of ALK mutations that can confer resistance to crizotinib. Mutations at 16 residues were identified, structurally clustered into five regions around the kinase active site, which conferred varying degrees of resistance. The screen successfully predicted the L1196M, C1156Y, and F1174L mutations, recently identified in crizotinib-resistant patients. In separate studies, we demonstrated that crizotinib has relatively modest potency in ALK-positive non-small-cell lung cancer cell lines. A more potent ALK inhibitor, TAE684, maintained substantial activity against mutations that conferred resistance to crizotinib. Our study identifies multiple novel mutations in ALK that may confer clinical resistance to crizotinib, suggests that crizotinib's narrow selectivity window may underlie its susceptibility to such resistance and demonstrates that a more potent ALK inhibitor may be effective at overcoming resistance.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Piridinas/farmacologia , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/genética , Quinase do Linfoma Anaplásico , Carcinoma Pulmonar de Células não Pequenas , Linhagem Celular Tumoral , Crizotinibe , Humanos , Neoplasias Pulmonares , Mutação , Pirimidinas/farmacologia , Receptores Proteína Tirosina Quinases/metabolismo
7.
Mol Cancer Ther ; 10(6): 1028-35, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21482694

RESUMO

Ponatinib (AP24534) is a novel multitargeted kinase inhibitor that potently inhibits native and mutant BCR-ABL at clinically achievable drug levels. Ponatinib also has in vitro inhibitory activity against a discrete set of kinases implicated in the pathogenesis of other hematologic malignancies, including FLT3, KIT, fibroblast growth factor receptor 1 (FGFR1), and platelet derived growth factor receptor α (PDGFRα). Here, using leukemic cell lines containing activated forms of each of these receptors, we show that ponatinib potently inhibits receptor phosphorylation and cellular proliferation with IC50 values comparable to those required for inhibition of BCR-ABL (0.3 to 20 nmol/L). The activity of ponatinib against the FLT3-ITD mutant, found in up to 30% of acute myeloid leukemia (AML) patients, was particularly notable. In MV4-11 (FLT3-ITD(+/+)) but not RS4;11 (FLT3-ITD(-/-)) AML cells, ponatinib inhibited FLT3 signaling and induced apoptosis at concentrations of less than 10 nmol/L. In an MV4-11 mouse xenograft model, once daily oral dosing of ponatinib led to a dose-dependent inhibition of signaling and tumor regression. Ponatinib inhibited viability of primary leukemic blasts from a FLT3-ITD positive AML patient (IC50 4 nmol/L) but not those isolated from 3 patients with AML expressing native FLT3. Overall, these results support the investigation of ponatinib in patients with FLT3-ITD-driven AML and other hematologic malignancies driven by KIT, FGFR1, or PDGFRα.


Assuntos
Neoplasias Hematológicas/tratamento farmacológico , Imidazóis/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Piridazinas/farmacologia , Receptores Proteína Tirosina Quinases/metabolismo , Tirosina Quinase 3 Semelhante a fms/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Neoplasias Hematológicas/enzimologia , Neoplasias Hematológicas/patologia , Humanos , Leucemia Mieloide Aguda/enzimologia , Leucemia Mieloide Aguda/patologia , Camundongos , Camundongos SCID , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-kit/metabolismo , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
8.
J Med Chem ; 53(12): 4701-19, 2010 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-20513156

RESUMO

In the treatment of chronic myeloid leukemia (CML) with BCR-ABL kinase inhibitors, the T315I gatekeeper mutant has emerged as resistant to all currently approved agents. This report describes the structure-guided design of a novel series of potent pan-inhibitors of BCR-ABL, including the T315I mutation. A key structural feature is the carbon-carbon triple bond linker which skirts the increased bulk of Ile315 side chain. Extensive SAR studies led to the discovery of development candidate 20g (AP24534), which inhibited the kinase activity of both native BCR-ABL and the T315I mutant with low nM IC(50)s, and potently inhibited proliferation of corresponding Ba/F3-derived cell lines. Daily oral administration of 20g significantly prolonged survival of mice injected intravenously with BCR-ABL(T315I) expressing Ba/F3 cells. These data, coupled with a favorable ADME profile, support the potential of 20g to be an effective treatment for CML, including patients refractory to all currently approved therapies.


Assuntos
Antineoplásicos/síntese química , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Imidazóis/síntese química , Inibidores de Proteínas Quinases/síntese química , Piridazinas/síntese química , Administração Oral , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Barreira Hematoencefálica/metabolismo , Linhagem Celular Tumoral , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Proteínas de Fusão bcr-abl/genética , Imidazóis/farmacocinética , Imidazóis/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Camundongos , Camundongos SCID , Modelos Moleculares , Mutação , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/farmacologia , Piridazinas/farmacocinética , Piridazinas/farmacologia , Ratos
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