RESUMO
Many advances in the treatment of cancer have been driven by the development of targeted therapies that inhibit oncogenic signaling pathways and tumor-associated angiogenesis, as well as by the recent development of therapies that activate a patient's immune system to unleash antitumor immunity. Some targeted therapies can have effects on host immune responses, in addition to their effects on tumor biology. These immune-modulating effects, such as increasing tumor antigenicity or promoting intratumoral T cell infiltration, provide a rationale for combining these targeted therapies with immunotherapies. Here, we discuss the immune-modulating effects of targeted therapies against the MAPK and VEGF signaling pathways, and how they may synergize with immunomodulatory antibodies that target PD1/PDL1 and CTLA4. We critically examine the rationale in support of these combinations in light of the current understanding of the underlying mechanisms of action of these therapies. We also discuss the available preclinical and clinical data for these combination approaches and their implications regarding mechanisms of action. Insights from these studies provide a framework for considering additional combinations of targeted therapies and immunotherapies for the treatment of cancer.
Assuntos
Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Imunoterapia/métodos , Neoplasias/terapia , Linfócitos T/imunologia , Animais , Antígeno B7-H1/imunologia , Antígeno CTLA-4/imunologia , Terapia Combinada , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Terapia de Alvo Molecular , Neoplasias/imunologia , Receptor de Morte Celular Programada 1/imunologia , Transdução de Sinais , Linfócitos T/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Based on lead compound 1, which was discovered from a high-throughput screen, a series of PI3Kα/mTOR inhibitors were evaluated that contained an imidazo[1,2-a]pyridine as a core replacement for the benzimidazole contained in 1. By exploring various ring systems that occupy the affinity pocket, two fragments containing a methoxypyridine were identified that gave <100 nM potency toward PI3Kα in enzyme and cellular assays with moderate stability in rat and human liver microsomes. With the two methoxypyridine groups selected to occupy the affinity pocket, analogs were prepared with various fragments intended to occupy the ribose pocket of PI3Kα and mTOR. From these analogs, tertiary alcohol 18 was chosen for in vivo pharmacodynamic evaluation based on its potency in the PI3Kα cellular assay, microsomal stability, and in vivo pharmacokinetic properties. In a mouse liver pharmacodynamic assay, compound 18 showed 56% inhibition of HFG-induced AKT (Ser473) phosphorylation at a 30 mg/kg dose.
Assuntos
Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Piridinas/química , Serina-Treonina Quinases TOR/antagonistas & inibidores , Animais , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Humanos , Camundongos , Microssomos Hepáticos/química , Microssomos Hepáticos/metabolismo , Modelos Moleculares , Estrutura Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/síntese química , Ratos , Relação Estrutura-Atividade , Serina-Treonina Quinases TOR/metabolismoRESUMO
Phosphoinositide 3-kinase (PI3K) is an important target in oncology due to the deregulation of the PI3K/Akt signaling pathway in a wide variety of tumors. A series of 4-amino-6-methyl-1,3,5-triazine sulfonamides were synthesized and evaluated as inhibitors of PI3K. The synthesis, in vitro biological activities, pharmacokinetic and in vivo pharmacodynamic profiling of these compounds are described. The most promising compound from this investigation (compound 3j) was found to be a pan class I PI3K inhibitor with a moderate (>10-fold) selectivity over the mammalian target of rapamycin (mTOR) in the enzyme assay. In a U87 MG cellular assay measuring phosphorylation of Akt, compound 3j displayed low double digit nanomolar IC(50) and exhibited good oral bioavailability in rats (F(oral)=63%). Compound 3j also showed a dose dependent reduction in the phosphorylation of Akt in a U87 tumor pharmacodynamic model with a plasma EC(50)=193 nM (91 ng/mL).
Assuntos
Neoplasias/tratamento farmacológico , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Sulfonamidas/química , Sulfonamidas/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Sítios de Ligação , Linhagem Celular Tumoral , Cristalografia por Raios X , Feminino , Humanos , Camundongos , Simulação de Acoplamento Molecular , Neoplasias/enzimologia , Neoplasias/metabolismo , Fosfatidilinositol 3-Quinases/química , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Sulfonamidas/farmacocinética , Sulfonamidas/uso terapêutico , Serina-Treonina Quinases TOR/metabolismo , Triazinas/química , Triazinas/farmacocinética , Triazinas/farmacologia , Triazinas/uso terapêuticoRESUMO
PURPOSE: Small-cell lung cancer (SCLC) is an aggressive neuroendocrine tumor with a high relapse rate, limited therapeutic options, and poor prognosis. We investigated the antitumor activity of AMG 757, a half-life extended bispecific T-cell engager molecule targeting delta-like ligand 3 (DLL3)-a target that is selectively expressed in SCLC tumors, but with minimal normal tissue expression. EXPERIMENTAL DESIGN: AMG 757 efficacy was evaluated in SCLC cell lines and in orthotopic and patient-derived xenograft (PDX) mouse SCLC models. Following AMG 757 administration, changes in tumor volume, pharmacodynamic changes in tumor-infiltrating T cells (TILs), and the spatial relationship between the appearance of TILs and tumor histology were examined. Tolerability was assessed in nonhuman primates (NHPs). RESULTS: AMG 757 showed potent and specific killing of even those SCLC cell lines with very low DLL3 expression (<1,000 molecules per cell). AMG 757 effectively engaged systemically administered human T cells, induced T-cell activation, and redirected T cells to lyse tumor cells to promote significant tumor regression and complete responses in PDX models of SCLC and in orthotopic models of established primary lung SCLC and metastatic liver lesions. AMG 757 was well tolerated with no AMG 757-related adverse findings up to the highest tested dose (4.5 mg/kg weekly) in NHP. AMG 757 exhibits an extended half-life in NHP, which is projected to enable intermittent administration in patients. CONCLUSIONS: AMG 757 has a compelling safety and efficacy profile in preclinical studies making it a viable option for targeting DLL3-expressing SCLC tumors in the clinical setting.
Assuntos
Anticorpos Biespecíficos , Anticorpos Monoclonais , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular , Neoplasias Pulmonares , Proteínas de Membrana , Carcinoma de Pequenas Células do Pulmão , Linfócitos T , Animais , Feminino , Humanos , Camundongos , Anticorpos Biespecíficos/farmacologia , Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Apoptose , Proliferação de Células , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Proteínas de Membrana/antagonistas & inibidores , Camundongos Endogâmicos NOD , Camundongos SCID , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/imunologia , Carcinoma de Pequenas Células do Pulmão/metabolismo , Carcinoma de Pequenas Células do Pulmão/patologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
PURPOSE: Angiogenesis plays a critical role in breast cancer development and progression. Vascular endothelial growth factor (VEGF) is a potent angiogenic factor that regulates endothelial cell proliferation and survival. We investigated the effects of motesanib, a novel, oral inhibitor of VEGF receptors 1, 2, and 3; platelet-derived growth factor receptor; and Kit receptor, on the growth of xenografts representing various human breast cancer subtypes. EXPERIMENTAL DESIGN: Athymic nude mice were implanted with MCF-7 (luminal) or MDA-MB-231 (mesenchymal) tumor fragments or Cal-51 (mixed/progenitor) tumor cells. Once tumors were established, animals were randomized to receive increasing doses of motesanib alone or motesanib plus cytotoxic chemotherapy (docetaxel, doxorubicin, or tamoxifen). RESULTS: Across all three xenograft models, motesanib treatment resulted in significant dose-dependent reductions in tumor growth, compared with vehicle-treated controls, and in marked reductions in viable tumor fraction and blood vessel density. No significant effect on body weight was observed with compound treatment compared with control-treated animals. Motesanib did not affect the proliferation of tumor cells in vitro. There was a significantly greater reduction in xenograft tumor growth when motesanib was combined with docetaxel (MDA-MB-231 tumors) or with the estrogen receptor modulator tamoxifen (MCF-7 tumors), compared with either treatment alone, but not when combined with doxorubicin (Cal-51 tumors). CONCLUSIONS: Treatment with motesanib alone or in combination with chemotherapy inhibits tumor growth in vivo in various models of human breast cancer. These data suggest that motesanib may have broad utility in the treatment of human breast cancer.
Assuntos
Inibidores da Angiogênese/uso terapêutico , Indóis/uso terapêutico , Neoplasias Mamárias Experimentais/tratamento farmacológico , Niacinamida/análogos & derivados , Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-kit/metabolismo , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Peso Corporal/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Neoplasias Mamárias Experimentais/irrigação sanguínea , Camundongos , Camundongos Nus , Niacinamida/uso terapêutico , Oligonucleotídeos , Distribuição Aleatória , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Chromosome 19 has the highest gene density of all human chromosomes, more than double the genome-wide average. The large clustered gene families, corresponding high G + C content, CpG islands and density of repetitive DNA indicate a chromosome rich in biological and evolutionary significance. Here we describe 55.8 million base pairs of highly accurate finished sequence representing 99.9% of the euchromatin portion of the chromosome. Manual curation of gene loci reveals 1,461 protein-coding genes and 321 pseudogenes. Among these are genes directly implicated in mendelian disorders, including familial hypercholesterolaemia and insulin-resistant diabetes. Nearly one-quarter of these genes belong to tandemly arranged families, encompassing more than 25% of the chromosome. Comparative analyses show a fascinating picture of conservation and divergence, revealing large blocks of gene orthology with rodents, scattered regions with more recent gene family expansions and deletions, and segments of coding and non-coding conservation with the distant fish species Takifugu.
Assuntos
Cromossomos Humanos Par 19/genética , Genes/genética , Mapeamento Físico do Cromossomo , Processamento Alternativo/genética , Animais , Composição de Bases , Sequência Conservada/genética , Ilhas de CpG/genética , Evolução Molecular , Duplicação Gênica , Genética Médica , Humanos , Camundongos , Dados de Sequência Molecular , Família Multigênica/genética , Pseudogenes/genética , Análise de Sequência de DNARESUMO
Receptor tyrosine kinase inhibitors have shown clinical benefit in clear cell renal cell carcinoma (ccRCC), but novel therapeutic strategies are needed. The angiopoietin/Tie2 and MET pathways have been implicated in tumor angiogenesis, metastases, and macrophage infiltration. In our study, we used trebananib, an angiopoietin 1/2 inhibitor, and a novel small-molecule MET kinase inhibitor in patient-derived xenograft (PDX) models of ccRCC. Our goal was to assess the ability of these compounds to alter the status of tumor-infiltrating macrophages, inhibit tumor growth and metastases, and prolong survival. Seven-week-old SCID mice were implanted subcutaneously or orthotopically with human ccRCC models. One month postimplantation, mice were treated with angiopoietin 1/2 inhibitor trebananib (AMG 386), MET kinase inhibitor, or combination. In our metastatic ccRCC PDX model, RP-R-02LM, trebananib alone, and in combination with a MET kinase inhibitor, significantly reduced lung metastases and M2 macrophage infiltration (P = 0.0075 and P = 0.0205, respectively). Survival studies revealed that treatment of the orthotopically implanted RP-R-02LM tumors yielded a significant increase in survival in both trebananib and combination groups. In addition, resection of the subcutaneously implanted primary tumor allowed for a significant survival advantage to the combination group compared with vehicle and both single-agent groups. Our results show that the combination of trebananib with a MET kinase inhibitor significantly inhibits the spread of metastases, reduces infiltrating M2-type macrophages, and prolongs survival in our highly metastatic ccRCC PDX model, suggesting a potential use for this combination therapy in treating patients with ccRCC.
Assuntos
Angiopoietina-2/genética , Carcinoma de Células Renais/genética , Animais , Carcinoma de Células Renais/mortalidade , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Camundongos SCID , Metástase Neoplásica , Análise de Sobrevida , Microambiente TumoralRESUMO
Myeloid cell leukemia sequence 1 (MCL-1) is an antiapoptotic protein that plays a key role in promoting cell survival in multiple myeloma (MM), acute myeloid leukemia (AML), and non-Hodgkin lymphoma (NHL). Overexpression of MCL-1 is associated with treatment resistance and poor prognosis; thus, MCL-1 inhibitors are rational therapeutic options for malignancies depending on MCL-1. Several MCL-1 inhibitors have entered clinical trials, including AZD5991, S64315, AMG 176, and AMG 397. A key area of investigation is whether MCL-1 inhibitors will complement the activity of BCL-2 inhibitors, such as venetoclax, and synergistically enhance anti-tumor efficacy when given in combination with other anti-cancer drugs. Another important question is whether a safe therapeutic window can be found for this new class of inhibitors. In summary, inhibition of MCL-1 shows potential as a treatment for hematologic malignancies and clinical evaluation of MCL-1 inhibitors is currently underway.
Assuntos
Antineoplásicos/farmacologia , Neoplasias Hematológicas/genética , Leucemia Mieloide Aguda/genética , Mieloma Múltiplo/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Animais , Antineoplásicos/uso terapêutico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/metabolismo , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Terapia de Alvo Molecular , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/análise , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacosRESUMO
Selective small molecule inhibitors of Tie-2 kinase are important tools for the validation of Tie-2 signaling in pathological angiogenesis. Reported herein is the optimization of a nonselective scaffold into a potent and highly selective inhibitor of Tie-2 kinase.
Assuntos
Benzimidazóis/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Receptor TIE-2/antagonistas & inibidores , Administração Oral , Benzimidazóis/administração & dosagem , Benzimidazóis/química , Disponibilidade Biológica , Cristalografia por Raios X , Células HeLa , Humanos , Modelos Moleculares , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/químicaRESUMO
Overexpression of the antiapoptotic protein Mcl-1 provides a survival advantage to some cancer cells, making inhibition of this protein an attractive therapeutic target for the treatment of certain types of tumors. Herein, we report our efforts toward the identification of a novel series of macrocyclic Mcl-1 inhibitors featuring an α-hydroxy phenylacetic acid pharmacophore or bioisostere. This work led to the discovery of 1, a potent Mcl-1 inhibitor (IC50 = 19 nM in an OPM-2 cell viability assay) with good pharmacokinetic properties and excellent in vivo efficacy in an OPM-2 multiple myeloma xenograft model.
Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Fenilacetatos/química , Administração Oral , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Disponibilidade Biológica , Linhagem Celular Tumoral , Cristalografia por Raios X , Desenho de Fármacos , Estabilidade de Medicamentos , Feminino , Humanos , Ligação de Hidrogênio , Camundongos Nus , Mieloma Múltiplo/tratamento farmacológico , Proteína de Sequência 1 de Leucemia de Células Mieloides/química , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Sulfonamidas/química , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BH3 mimetic drugs, which inhibit prosurvival BCL2 family proteins, have limited single-agent activity in solid tumor models. The potential of BH3 mimetics for these cancers may depend on their ability to potentiate the apoptotic response to chemotherapy and targeted therapies. Using a novel class of potent and selective MCL1 inhibitors, we demonstrate that concurrent MEK + MCL1 inhibition induces apoptosis and tumor regression in KRAS-mutant non-small cell lung cancer (NSCLC) models, which respond poorly to MEK inhibition alone. Susceptibility to BH3 mimetics that target either MCL1 or BCL-xL was determined by the differential binding of proapoptotic BCL2 proteins to MCL1 or BCL-xL, respectively. The efficacy of dual MEK + MCL1 blockade was augmented by prior transient exposure to BCL-xL inhibitors, which promotes the binding of proapoptotic BCL2 proteins to MCL1. This suggests a novel strategy for integrating BH3 mimetics that target different BCL2 family proteins for KRAS-mutant NSCLC. SIGNIFICANCE: Defining the molecular basis for MCL1 versus BCL-xL dependency will be essential for effective prioritization of BH3 mimetic combination therapies in the clinic. We discover a novel strategy for integrating BCL-xL and MCL1 inhibitors to drive and subsequently exploit apoptotic dependencies of KRAS-mutant NSCLCs treated with MEK inhibitors.See related commentary by Leber et al., p. 1511.This article is highlighted in the In This Issue feature, p. 1494.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Células A549 , Compostos de Anilina/administração & dosagem , Compostos de Anilina/farmacologia , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Benzamidas/farmacologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Difenilamina/análogos & derivados , Difenilamina/farmacologia , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Camundongos Knockout , Camundongos Nus , Camundongos SCID , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Sulfonamidas/administração & dosagem , Sulfonamidas/farmacologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto/métodosRESUMO
The prosurvival BCL2 family member MCL1 is frequently dysregulated in cancer. To overcome the significant challenges associated with inhibition of MCL1 protein-protein interactions, we rigorously applied small-molecule conformational restriction, which culminated in the discovery of AMG 176, the first selective MCL1 inhibitor to be studied in humans. We demonstrate that MCL1 inhibition induces a rapid and committed step toward apoptosis in subsets of hematologic cancer cell lines, tumor xenograft models, and primary patient samples. With the use of a human MCL1 knock-in mouse, we demonstrate that MCL1 inhibition at active doses of AMG 176 is tolerated and correlates with clear pharmacodynamic effects, demonstrated by reductions in B cells, monocytes, and neutrophils. Furthermore, the combination of AMG 176 and venetoclax is synergistic in acute myeloid leukemia (AML) tumor models and in primary patient samples at tolerated doses. These results highlight the therapeutic promise of AMG 176 and the potential for combinations with other BH3 mimetics. SIGNIFICANCE: AMG 176 is a potent, selective, and orally bioavailable MCL1 inhibitor that induces a rapid commitment to apoptosis in models of hematologic malignancies. The synergistic combination of AMG 176 and venetoclax demonstrates robust activity in models of AML at tolerated doses, highlighting the promise of BH3-mimetic combinations in hematologic cancers.See related commentary by Leber et al., p. 1511.This article is highlighted in the In This Issue feature, p. 1494.
RESUMO
Inhibition of angiogenesis is a promising and clinically validated approach for limiting tumor growth and survival. The receptor tyrosine kinase Tie-2 is expressed almost exclusively in the vascular endothelium and is required for developmental angiogenesis and vessel maturation. However, the significance of Tie-2 signaling in tumor angiogenesis is not well understood. In order to evaluate the therapeutic utility of inhibiting Tie-2 signaling, we developed a series of potent and orally bioavailable small molecule Tie-2 kinase inhibitors with selectivity over other kinases, especially those that are believed to be important for tumor angiogenesis. Our earlier work provided pyridinyl pyrimidine 6 as a potent, nonselective Tie-2 inhibitor that was designed on the basis of X-ray cocrystal structures of KDR inhibitors 34 (triazine) and 35 (nicotinamide). Lead optimization resulted in pyridinyl triazine 63, which exhibited >30-fold selectivity over a panel of kinases, good oral exposure, and in vivo inhibition of Tie-2 phosphorylation.
Assuntos
Inibidores da Angiogênese/síntese química , Benzamidas/síntese química , Piridinas/síntese química , Receptor TIE-2/antagonistas & inibidores , Triazinas/síntese química , Administração Oral , Inibidores da Angiogênese/farmacocinética , Inibidores da Angiogênese/farmacologia , Animais , Benzamidas/farmacocinética , Benzamidas/farmacologia , Sítios de Ligação , Proteínas Sanguíneas/metabolismo , Cristalografia por Raios X , Feminino , Humanos , Injeções Intraperitoneais , Injeções Intravenosas , Masculino , Camundongos , Modelos Moleculares , Estrutura Molecular , Fosforilação , Ligação Proteica , Piridinas/farmacocinética , Piridinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptor TIE-2/química , Receptor TIE-2/metabolismo , Relação Estrutura-Atividade , Triazinas/farmacocinética , Triazinas/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidoresRESUMO
The recognition that aberrant angiogenesis contributes to the pathology of inflammatory diseases, cancer, and myocardial ischemia has generated considerable interest in the molecular mechanisms that regulate blood vessel growth. The receptor tyrosine kinase Tie-2 is expressed primarily by vascular endothelial cells and is critical for embryonic vasculogenesis. Interference with the Tie-2 pathway by diverse blocking agents such as soluble Tie-2 receptors, anti-Tie-2 intrabodies, anti-Ang-2 antibodies, and peptide-Fc conjugates has been shown to suppress tumor growth in xenograft studies. An alternative strategy for interfering with the Tie-2 signaling pathway involves direct inhibition of the kinase functions of the Tie-2 receptor. Herein we describe the development of alkynylpyrimidine amide derivatives as potent, selective, and orally available ATP-competitive inhibitors of Tie-2 autophosphorylation.
Assuntos
Alcinos/síntese química , Amidas/síntese química , Inibidores da Angiogênese/síntese química , Pirimidinas/síntese química , Receptor TIE-2/antagonistas & inibidores , Trifosfato de Adenosina/metabolismo , Alcinos/farmacocinética , Alcinos/farmacologia , Amidas/farmacocinética , Amidas/farmacologia , Inibidores da Angiogênese/farmacocinética , Inibidores da Angiogênese/farmacologia , Animais , Sítios de Ligação , Proteínas Sanguíneas/metabolismo , Linhagem Celular , Feminino , Humanos , Técnicas In Vitro , Pulmão/efeitos dos fármacos , Pulmão/enzimologia , Masculino , Camundongos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Fosforilação , Ligação Proteica , Pirimidinas/farmacocinética , Pirimidinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptor TIE-2/metabolismo , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
Therapeutic resistance is a major obstacle to achieving durable clinical responses with targeted therapies, highlighting a need to elucidate the underlying mechanisms responsible for resistance and identify strategies to overcome this challenge. An emerging body of data implicates the tyrosine kinase MET in mediating resistance to BRAF inhibitors in BRAFV600E mutant melanoma. In this study we observed a dominant role for the HGF/MET axis in mediating resistance to BRAF and MEK inhibitors in models of BRAFV600E and NRAS mutant melanoma. In addition, we showed that MAPK pathway inhibition induced rapid increases in MET and GAB1 levels, providing novel mechanistic insight into how BRAFV600E mutant melanoma is primed for HGF-mediated rescue. We also determined that tumor-derived HGF, not systemic HGF, may be required to convey resistance to BRAF inhibition in vivo and that resistance could be reversed following treatment with AMG 337, a selective MET inhibitor. In summary, these findings support the clinical evaluation of MET-directed targeted therapy to circumvent resistance to BRAF and MEK inhibitors in BRAFV600E mutant melanoma. In addition, the induction of MET following treatment with BRAF and MEK inhibitors has the potential to serve as a predictive biomarker for identifying patients best suited for MET inhibitor combination therapy.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antineoplásicos/farmacologia , Fator de Crescimento de Hepatócito/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melanoma/patologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Benzamidas/farmacologia , Linhagem Celular Tumoral , Dipeptídeos/farmacologia , Difenilamina/análogos & derivados , Difenilamina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Indóis/farmacologia , Melanoma/genética , Camundongos , Camundongos Nus , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Piridonas/farmacologia , Sulfonamidas/farmacologia , Triazóis/farmacologia , Vemurafenib , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The receptor tyrosine kinase (RTK) MET represents a promising tumor target in a subset of glioblastomas. Most RTK inhibitors available in the clinic today, including those inhibiting MET, affect multiple targets simultaneously. Previously, it was demonstrated that treatment with cabozantinib (MET/VEGFR2/RET inhibitor) prolonged survival of mice carrying orthotopic patient-derived xenografts (PDX) of the MET-addicted glioblastoma model E98, yet did not prevent development of recurrent and cabozantinib-resistant tumors. To exclude VEGFR2 inhibition-inflicted blood-brain barrier normalization and diminished tumor distribution of the drug, we have now investigated the effects of the novel MET-selective inhibitor Compound A in the orthotopic E98 xenograft model. In vitro, Compound A proved a highly potent inhibitor of proliferation of MET-addicted cell lines. In line with its target selectivity, Compound A did not restore the leaky blood-brain barrier and was more effective than cabozantinib in inhibiting MET phosphorylation in vivo Compound A treatment significantly prolonged survival of mice carrying E98 tumor xenografts, but did not prevent eventual progression. Contrasting in vitro results, the Compound A-treated xenografts displayed high levels of AKT phosphorylation despite the absence of phosphorylated MET. Profiling by RNA sequencing showed that in vivo transcriptomes differed significantly from those in control xenografts.Implications: Collectively, these findings demonstrate the plasticity of paracrine growth factor receptor signaling in vivo and urge for prudency with in vitro drug-testing strategies to validate monotherapies. Mol Cancer Res; 15(11); 1587-97. ©2017 AACR.
Assuntos
Aminopiridinas/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Perfilação da Expressão Gênica/métodos , Glioma/tratamento farmacológico , Pirazóis/administração & dosagem , Análise de Sequência de RNA/métodos , Bibliotecas de Moléculas Pequenas/administração & dosagem , Aminopiridinas/farmacologia , Animais , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioma/genética , Células HT29 , Humanos , Camundongos , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Mouse double minute 2 (MDM2) is a critical negative regulator of the tumor suppressor p53, playing a key role in controlling its transcriptional activity, protein stability, and nuclear localization. MDM2 expression is up-regulated in numerous cancers, resulting in a loss of p53-dependent activities, such as apoptosis and cell-cycle arrest. Genetic amplification and inheritance of MDM2 promoter single-nucleotide polymorphisms (SNPs) are the two best-studied mechanisms for up-regulating MDM2 activity. This article provides an overview of these events in human cancer, highlighting the frequent occurrence of MDM2 amplification in sarcoma and the role of SNP309 and SNP285 in regulating MDM2 expression and cancer risk. The availability of large-scale genomic profiling datasets, like those from The Cancer Genome Atlas Research Network, have provided the opportunity to evaluate the consequences of MDM2 amplification and SNP inheritance across high-quality tumor samples from diverse cancer indications.
Assuntos
Transformação Celular Neoplásica/genética , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteína Supressora de Tumor p53/genética , Animais , Amplificação de Genes , Humanos , Camundongos , Camundongos Knockout , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Aberrant hepatocyte growth factor (HGF)/MET signaling has been implicated in hepatocarcinogenesis, suggesting that MET may serve as an attractive therapeutic target in hepatocellular carcinoma. We sought to investigate the in vitro and in vivo antitumor activity of AMG 337, a potent and highly selective small molecule MET kinase inhibitor, in preclinical models of hepatocellular carcinoma. The antiproliferative activity of AMG 337 was evaluated across a panel of hepatocellular carcinoma cell lines in a viability assay. Daily oral administration was used to evaluate the in vivo antitumor activity of AMG 337 in two patient-derived xenograft (PDX) models of hepatocellular carcinoma (LI0612 and LI1078). AMG 337 exerted potent antiproliferative activity against 2 of 40 hepatocellular carcinoma cell lines, namely, MHCC97H (IC50, 0.015 µmol/L) and HCCLM3 (IC50, 0.025 µmol/L). Both sensitive cell lines showed MET amplification (MET/CEN-7 >2.0) assessed by FISH, and high MET expression (3+ IHC) assessed by IHC. AMG 337 potently inhibited p-MET in all cell lines with detectable levels of total MET. However, the dose-dependent inhibition of downstream effectors of HGF/MET signaling, including p-GAB1, p-AKT, and p-ERK, was limited to those cell lines sensitive to AMG 337 in a viability assay (MHCC97H and HCCLM3). AMG 337 significantly inhibited tumor growth at all doses tested in the MET-amplified and MET-high-expressing hepatocellular carcinoma PDX model LI0612 and had no effect on tumor growth in the non-MET-amplified and MET-low-expressing hepatocellular carcinoma PDX model LI1078. AMG 337 represents a promising and novel therapeutic strategy for targeting hepatocellular carcinomas with a dependence on HGF/MET signaling. Mol Cancer Ther; 15(6); 1227-37. ©2016 AACR.
Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Piridonas/administração & dosagem , Bibliotecas de Moléculas Pequenas/administração & dosagem , Triazóis/administração & dosagem , Administração Oral , Animais , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/genética , Camundongos , Proteínas Proto-Oncogênicas c-met/genética , Piridonas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Triazóis/farmacologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The MET receptor tyrosine kinase is involved in cell growth, survival, and invasion. Clinical studies with small molecule MET inhibitors have shown the role of biomarkers in identifying patients most likely to benefit from MET-targeted therapy. AMG 337 is an oral, small molecule, ATP-competitive, highly selective inhibitor of the MET receptor. Herein, we describe AMG 337 preclinical activity and mechanism of action in MET-dependent tumor models. These studies suggest MET is the only therapeutic target for AMG 337. In an unbiased tumor cell line proliferation screen (260 cell lines), a closely related analogue of AMG 337, Compound 5, exhibited activity in 2 of 260 cell lines; both were MET-amplified. Additional studies examining the effects of AMG 337 on the proliferation of a limited panel of cell lines with varying MET copy numbers revealed that high-level focal MET amplification (>12 copies) was required to confer MET oncogene addiction and AMG 337 sensitivity. One MET-amplified cell line, H1573 (>12 copies), was AMG 337 insensitive, possibly because of a downstream G12A KRAS mutation. Mechanism-of-action studies in sensitive MET-amplified cell lines demonstrated that AMG 337 inhibited MET and adaptor protein Gab-1 phosphorylation, subsequently blocking the downstream PI3K and MAPK pathways. AMG 337 exhibited potency in pharmacodynamic assays evaluating MET signaling in tumor xenograft models; >90% inhibition of Gab-1 phosphorylation was observed at 0.75 mg/kg. These findings describe the preclinical activity and mechanism of action of AMG 337 in MET-dependent tumor models and indicate its potential as a novel therapeutic for the treatment of MET-dependent tumors. Mol Cancer Ther; 15(7); 1568-79. ©2016 AACR.
Assuntos
Antineoplásicos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Amplificação de Genes , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Necrose , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Previous reports have provided evidence that p53 mutation is a strong negative predictor of response to MDM2 inhibitors. However, this correlation is not absolute, as many p53Mutant cell lines have been reported to respond to MDM2 inhibition, while many p53WT cell lines have been shown not to respond. To better understand the nature of these exceptions, we screened a panel of 260 cell lines and noted similar discrepancies. However, upon extensive curation of this panel, these apparent exceptions could be eliminated, revealing a perfect correlation between p53 mutational status and MDM2 inhibitor responsiveness. It has been suggested that the MDM2-amplified subset of p53WT tumors might be particularly sensitive to MDM2 inhibition. To facilitate clinical testing of this hypothesis, we identified a rationally derived copy number cutoff for assignment of functionally relevant MDM2 amplification. Applying this cutoff resulted in a pan-cancer MDM2 amplification rate far lower than previously published.