RESUMO
The branched-chain amino acid transaminases (BCATs) are enzymes that catalyze the first reaction of catabolism of the essential branched-chain amino acids to branched-chain keto acids to form glutamate. They are known to play a key role in different cancer types. Here, we report a new structural class of BCAT1/2 inhibitors, (trifluoromethyl)pyrimidinediones, identified by a high-throughput screening campaign and subsequent optimization guided by a series of X-ray crystal structures. Our potent dual BCAT1/2 inhibitor BAY-069 displays high cellular activity and very good selectivity. Along with a negative control (BAY-771), BAY-069 was donated as a chemical probe to the Structural Genomics Consortium.
Assuntos
Aminoácidos de Cadeia Ramificada , Transaminases , Transaminases/metabolismo , Aminoácidos de Cadeia Ramificada/metabolismo , Cetoácidos/metabolismoRESUMO
We report on the discovery of the new clinical candidate BAY 1003803 as glucocorticoid receptor agonist for the topical treatment of psoriasis or severe atopic dermatitis. In the course of optimizing the amino alcohol series as a highly potent new non-steroidal lead structure, considerations were made as to how physicochemical properties and safety concerns relate to structural motifs. BAY 1003803 demonstrates strong anti-inflammatory activity in vitro paired with a pharmacokinetic profile suitable for topical application.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Descoberta de Drogas , Receptores de Glucocorticoides/agonistas , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Cães , Relação Dose-Resposta a Droga , Feminino , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Masculino , Estrutura Molecular , Ratos , Receptores de Glucocorticoides/metabolismo , Relação Estrutura-AtividadeRESUMO
Inhibition of monopolar spindle 1 (MPS1) kinase represents a novel approach to cancer treatment: instead of arresting the cell cycle in tumor cells, cells are driven into mitosis irrespective of DNA damage and unattached/misattached chromosomes, resulting in aneuploidy and cell death. Starting points for our optimization efforts with the goal to identify MPS1 inhibitors were two HTS hits from the distinct chemical series "triazolopyridines" and "imidazopyrazines". The major initial issue of the triazolopyridine series was the moderate potency of the HTS hits. The imidazopyrazine series displayed more than 10-fold higher potencies; however, in the early project phase, this series suffered from poor metabolic stability. Here, we outline the evolution of the two hit series to clinical candidates BAY 1161909 and BAY 1217389 and reveal how both clinical candidates bind to the ATP site of MPS1 kinase, while addressing different pockets utilizing different binding interactions, along with their synthesis and preclinical characterization in selected in vivo efficacy models.
Assuntos
Antineoplásicos/metabolismo , Proteínas de Ciclo Celular/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Descoberta de Drogas/métodos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Fuso Acromático/efeitos dos fármacos , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Proteínas de Ciclo Celular/antagonistas & inibidores , Linhagem Celular Tumoral , Cães , Feminino , Células HT29 , Células HeLa , Humanos , Pontos de Checagem da Fase M do Ciclo Celular/fisiologia , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Estrutura Terciária de Proteína , Proteínas Tirosina Quinases/antagonistas & inibidores , Ratos , Ratos Wistar , Fuso Acromático/metabolismo , Resultado do TratamentoRESUMO
We recently described glutathione peroxidase 4 (GPX4) as a promising target for killing therapy-resistant cancer cells via ferroptosis. The onset of therapy resistance by multiple types of treatment results in a stable cell state marked by high levels of polyunsaturated lipids and an acquired dependency on GPX4. Unfortunately, all existing inhibitors of GPX4 act covalently via a reactive alkyl chloride moiety that confers poor selectivity and pharmacokinetic properties. Here, we report our discovery that masked nitrile-oxide electrophiles, which have not been explored previously as covalent cellular probes, undergo remarkable chemical transformations in cells and provide an effective strategy for selective targeting of GPX4. The new GPX4-inhibiting compounds we describe exhibit unexpected proteome-wide selectivity and, in some instances, vastly improved physiochemical and pharmacokinetic properties compared to existing chloroacetamide-based GPX4 inhibitors. These features make them superior tool compounds for biological interrogation of ferroptosis and constitute starting points for development of improved inhibitors of GPX4.
Assuntos
Inibidores Enzimáticos/farmacologia , Nitrilas/química , Nitrilas/farmacologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/antagonistas & inibidores , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Animais , Linhagem Celular Tumoral , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Ferroptose/efeitos dos fármacos , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos SCID , Sondas Moleculares/química , Terapia de Alvo Molecular , Óxidos/química , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/química , Pró-Fármacos/química , Ratos Wistar , Selenocisteína/química , Selenocisteína/metabolismo , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-AtividadeRESUMO
The lactate transporter SLC16A1/monocarboxylate transporter 1 (MCT1) plays a central role in tumor cell energy homeostasis. In a cell-based screen, we identified a novel class of MCT1 inhibitors, including BAY-8002, which potently suppress bidirectional lactate transport. We investigated the antiproliferative activity of BAY-8002 in a panel of 246 cancer cell lines and show that hematopoietic tumor cells, in particular diffuse large B-cell lymphoma cell lines, and subsets of solid tumor models are particularly sensitive to MCT1 inhibition. Associated markers of sensitivity were, among others, lack of MCT4 expression, low pleckstrin homology like domain family A member 2, and high pellino E3 ubiquitin protein ligase 1 expression. The antitumor effect of MCT1 inhibition was less pronounced on tumor xenografts, with tumor stasis being the maximal response. BAY-8002 significantly increased intratumor lactate levels and transiently modulated pyruvate levels. In order to address potential acquired resistance mechanisms to MCT1 inhibition, we generated MCT1 inhibitor-resistant cell lines and show that resistance can occur by upregulation of MCT4 even in the presence of sufficient oxygen, as well as by shifting energy generation toward oxidative phosphorylation. These findings provide insight into novel aspects of tumor response to MCT1 modulation and offer further rationale for patient selection in the clinical development of MCT1 inhibitors. Mol Cancer Ther; 17(11); 2285-96. ©2018 AACR.
Assuntos
Aminobenzoatos/farmacologia , Benzoatos/farmacologia , Biomarcadores Tumorais/metabolismo , Resistencia a Medicamentos Antineoplásicos , Transportadores de Ácidos Monocarboxílicos/antagonistas & inibidores , Sulfonas/farmacologia , Simportadores/antagonistas & inibidores , Aminobenzoatos/química , Animais , Benzoatos/química , Transporte Biológico/efeitos dos fármacos , Radioisótopos de Carbono , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Fluorescência , Humanos , Concentração de Íons de Hidrogênio , Ácido Láctico/metabolismo , Camundongos SCID , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Musculares/metabolismo , Pirimidinonas/farmacologia , Ácido Pirúvico/metabolismo , Sulfonas/química , Simportadores/metabolismo , Tiofenos/farmacologia , Resultado do Tratamento , Xenopus laevisRESUMO
MTH1 is a hydrolase responsible for sanitization of oxidized purine nucleoside triphosphates to prevent their incorporation into replicating DNA. Early tool compounds published in the literature inhibited the enzymatic activity of MTH1 and subsequently induced cancer cell death; however recent studies have questioned the reported link between these two events. Therefore, it is important to validate MTH1 as a cancer dependency with high quality chemical probes. Here, we present BAY-707, a substrate-competitive, highly potent and selective inhibitor of MTH1, chemically distinct compared to those previously published. Despite superior cellular target engagement and pharmacokinetic properties, inhibition of MTH1 with BAY-707 resulted in a clear lack of in vitro or in vivo anticancer efficacy either in mono- or in combination therapies. Therefore, we conclude that MTH1 is dispensable for cancer cell survival.
Assuntos
Enzimas Reparadoras do DNA/metabolismo , Sistemas de Liberação de Medicamentos , Morfolinas/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Monoéster Fosfórico Hidrolases/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Células CACO-2 , Células Cultivadas , Enzimas Reparadoras do DNA/antagonistas & inibidores , Ativação Enzimática/efeitos dos fármacos , Células HeLa , Hepatócitos/efeitos dos fármacos , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , Microssomos Hepáticos/efeitos dos fármacos , Modelos Moleculares , Morfolinas/química , Neoplasias/fisiopatologia , Monoéster Fosfórico Hidrolases/antagonistas & inibidores , Pirimidinas/química , Pirimidinas/farmacologia , RatosRESUMO
Owing to lagging or insufficient neo-angiogenesis, hypoxia is a feature of most solid tumors. Hypoxic tumor regions contribute to resistance against antiproliferative chemotherapeutics, radiotherapy and immunotherapy. Targeting cells in hypoxic tumor areas is therefore an important strategy for cancer treatment. Most approaches for targeting hypoxic cells focus on the inhibition of hypoxia adaption pathways but only a limited number of compounds with the potential to specifically target hypoxic tumor regions have been identified. By using tumor spheroids in hypoxic conditions as screening system, we identified a set of compounds, including the phenothiazine antipsychotic Fluphenazine, as hits with novel mode of action. Fluphenazine functionally inhibits acid sphingomyelinase and causes cellular sphingomyelin accumulation, which induces cancer cell death specifically in hypoxic tumor spheroids. Moreover, we found that functional inhibition of acid sphingomyelinase leads to overactivation of hypoxia stress-response pathways and that hypoxia-specific cell death is mediated by the stress-responsive transcription factor ATF4. Taken together, the here presented data suggest a novel, yet unexplored mechanism in which induction of sphingolipid stress leads to the overactivation of hypoxia stress-response pathways and thereby promotes their pro-apoptotic tumor-suppressor functions to specifically kill cells in hypoxic tumor areas.
Assuntos
Neoplasias do Colo/enzimologia , Flufenazina/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Esfingomielina Fosfodiesterase/antagonistas & inibidores , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Morte Celular/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/genética , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Humanos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Esfingomielina Fosfodiesterase/genéticaRESUMO
Mutations in codon 132 of isocitrate dehydrogenase (IDH) 1 are frequent in diffuse glioma, acute myeloid leukemia, chondrosarcoma and intrahepatic cholangiocarcinoma. These mutations result in a neomorphic enzyme specificity which leads to a dramatic increase of intracellular D-2-hydroxyglutarate (2-HG) in tumor cells. Therefore, mutant IDH1 protein is a highly attractive target for inhibitory drugs. Here, we describe the development and properties of BAY 1436032, a pan-inhibitor of IDH1 protein with different codon 132 mutations. BAY 1436032 strongly reduces 2-HG levels in cells carrying IDH1-R132H, -R132C, -R132G, -R132S and -R132L mutations. Cells not carrying IDH mutations were unaffected. BAY 1436032 did not exhibit toxicity in vitro or in vivo. The pharmacokinetic properties of BAY 1436032 allow for oral administration. In two independent experiments, BAY 1436032 has been shown to significantly prolong survival of mice intracerebrally transplanted with human astrocytoma carrying the IDH1R132H mutation. In conclusion, we developed a pan-inhibitor targeting tumors with different IDH1R132 mutations.
Assuntos
Compostos de Anilina/farmacologia , Antineoplásicos/farmacologia , Astrocitoma/tratamento farmacológico , Benzimidazóis/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Isocitrato Desidrogenase/antagonistas & inibidores , Isocitrato Desidrogenase/genética , Compostos de Anilina/química , Compostos de Anilina/farmacocinética , Compostos de Anilina/toxicidade , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/toxicidade , Astrocitoma/enzimologia , Astrocitoma/genética , Benzimidazóis/química , Benzimidazóis/farmacocinética , Benzimidazóis/toxicidade , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/enzimologia , Neoplasias do Colo/genética , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/toxicidade , Escherichia coli , Feminino , Glutaratos/metabolismo , Células HEK293 , Humanos , Isocitrato Desidrogenase/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Mutação , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sarcoma/tratamento farmacológico , Sarcoma/enzimologia , Sarcoma/genética , Células Sf9 , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The PI3K-AKT-mTOR signaling cascade is activated in the majority of human cancers, and its activation also plays a key role in resistance to chemo and targeted therapeutics. In particular, in both breast and prostate cancer, increased AKT pathway activity is associated with cancer progression, treatment resistance and poor disease outcome. Here, we evaluated the activity of a novel allosteric AKT1/2 inhibitor, BAY 1125976, in biochemical, cellular mechanistic, functional and in vivo efficacy studies in a variety of tumor models. In in vitro kinase activity assays, BAY 1125976 potently and selectively inhibited the activity of full-length AKT1 and AKT2 by binding into an allosteric binding pocket formed by kinase and PH domain. In accordance with this proposed allosteric binding mode, BAY 1125976 bound to inactive AKT1 and inhibited T308 phosphorylation by PDK1, while the activity of truncated AKT proteins lacking the pleckstrin homology domain was not inhibited. In vitro, BAY 1125976 inhibited cell proliferation in a broad panel of human cancer cell lines. Particularly high activity was observed in breast and prostate cancer cell lines expressing estrogen or androgen receptors. Furthermore, BAY 1125976 exhibited strong in vivo efficacy in both cell line and patient-derived xenograft models such as the KPL4 breast cancer model (PIK3CAH1074R mutant), the MCF7 and HBCx-2 breast cancer models and the AKTE17K mutant driven prostate cancer (LAPC-4) and anal cancer (AXF 984) models. These findings indicate that BAY 1125976 is a potent and highly selective allosteric AKT1/2 inhibitor that targets tumors displaying PI3K/AKT/mTOR pathway activation, providing opportunities for the clinical development of new, effective treatments.
Assuntos
Nitrilas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Sulfonas/farmacologia , Animais , Células CACO-2 , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Células HeLa , Humanos , Células MCF-7 , Masculino , Camundongos , Camundongos Nus , Camundongos SCID , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto/métodosRESUMO
Despite the long-known fact that the facilitative glucose transporter GLUT1 is one of the key players safeguarding the increase in glucose consumption of many tumor entities even under conditions of normal oxygen supply (known as the Warburg effect), only few endeavors have been undertaken to find a GLUT1-selective small-molecule inhibitor. Because other transporters of the GLUT1 family are involved in crucial processes, these transporters should not be addressed by such an inhibitor. A high-throughput screen against a library of â¼3â million compounds was performed to find a small molecule with this challenging potency and selectivity profile. The N-(1H-pyrazol-4-yl)quinoline-4-carboxamides were identified as an excellent starting point for further compound optimization. After extensive structure-activity relationship explorations, single-digit nanomolar inhibitors with a selectivity factor of >100 against GLUT2, GLUT3, and GLUT4 were obtained. The most promising compound, BAY-876 [N4 -[1-(4-cyanobenzyl)-5-methyl-3-(trifluoromethyl)-1H-pyrazol-4-yl]-7-fluoroquinoline-2,4-dicarboxamide], showed good metabolic stability inâ vitro and high oral bioavailability inâ vivo.
Assuntos
Transportador de Glucose Tipo 1/antagonistas & inibidores , Pirazóis/farmacologia , Quinolinas/farmacologia , Administração Oral , Disponibilidade Biológica , Transportador de Glucose Tipo 1/metabolismo , Ensaios de Triagem em Larga Escala , Humanos , Estrutura Molecular , Pirazóis/administração & dosagem , Pirazóis/química , Quinolinas/administração & dosagem , Quinolinas/química , Relação Estrutura-AtividadeAssuntos
Antineoplásicos/uso terapêutico , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacologia , Metformina/administração & dosagem , Metformina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/patologiaRESUMO
The compound class of 1H-pyrazolo[3,4-d]pyrimidines was identified using HTS as very potent inhibitors of facilitated glucose transporter 1 (GLUT1). Extensive structure-activity relationship studies (SAR) of each ring system of the molecular framework was established revealing essential structural motives (i.e., ortho-methoxy substituted benzene, piperazine and pyrimidine). The selectivity against GLUT2 was excellent and initial in vitro and in vivo pharmacokinetic (PK) studies are encouraging.
Assuntos
Transportador de Glucose Tipo 1/antagonistas & inibidores , Pirimidinas/química , Pirimidinas/farmacologia , Animais , Linhagem Celular , Descoberta de Drogas , Transportador de Glucose Tipo 1/metabolismo , Humanos , Masculino , Pirimidinas/farmacocinética , Ratos Wistar , Relação Estrutura-AtividadeRESUMO
Monopolar spindle 1 (Mps1) has been shown to function as the key kinase that activates the spindle assembly checkpoint (SAC) to secure proper distribution of chromosomes to daughter cells. Here, we report the structure and functional characterization of two novel selective Mps1 inhibitors, BAY 1161909 and BAY 1217389, derived from structurally distinct chemical classes. BAY 1161909 and BAY 1217389 inhibited Mps1 kinase activity with IC50 values below 10 nmol/L while showing an excellent selectivity profile. In cellular mechanistic assays, both Mps1 inhibitors abrogated nocodazole-induced SAC activity and induced premature exit from mitosis ("mitotic breakthrough"), resulting in multinuclearity and tumor cell death. Both compounds efficiently inhibited tumor cell proliferation in vitro (IC50 nmol/L range). In vivo, BAY 1161909 and BAY 1217389 achieved moderate efficacy in monotherapy in tumor xenograft studies. However, in line with its unique mode of action, when combined with paclitaxel, low doses of Mps1 inhibitor reduced paclitaxel-induced mitotic arrest by the weakening of SAC activity. As a result, combination therapy strongly improved efficacy over paclitaxel or Mps1 inhibitor monotreatment at the respective MTDs in a broad range of xenograft models, including those showing acquired or intrinsic paclitaxel resistance. Both Mps1 inhibitors showed good tolerability without adding toxicity to paclitaxel monotherapy. These preclinical findings validate the innovative concept of SAC abrogation for cancer therapy and justify clinical proof-of-concept studies evaluating the Mps1 inhibitors BAY 1161909 and BAY 1217389 in combination with antimitotic cancer drugs to enhance their efficacy and potentially overcome resistance. Mol Cancer Ther; 15(4); 583-92. ©2016 AACR.
Assuntos
Antineoplásicos/farmacologia , Proteínas de Ciclo Celular/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Animais , Antineoplásicos/química , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Masculino , Camundongos , Mitose/efeitos dos fármacos , Inibidores de Proteínas Quinases/química , Ratos , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Androgen receptor (AR) mutations arise in patients developing resistance to hormone deprivation therapies. Here we describe BAY 1024767, a thiohydantoin derivative with strong antagonistic activity against nine AR variants with mutations located in the AR ligand-binding domain (LBD), and against wild-type AR. Antagonism was maintained, though reduced, at increased androgen levels. Anti-tumor efficacy was evidenced in vivo in the KuCaP-1 prostate cancer model which bears the W741C bicalutamide resistance mutation and in the syngeneic prostate cancer rat model Dunning R3327-G. The prevalence of six selected AR mutations was determined in plasma DNA originating from 100 resistant patients and found to be at least 12%. Altogether the results show BAY 1024767 to be a strong antagonist for several AR mutants linked to therapy resistance, which opens the door for next-generation compounds that can benefit patients based on their mutation profile.
Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Receptores Androgênicos/genética , Tioidantoínas/farmacologia , Animais , Células COS , Células CACO-2 , Linhagem Celular Tumoral , Chlorocebus aethiops , Regulação para Baixo , Humanos , Masculino , Camundongos , Camundongos SCID , Mutação , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/metabolismo , Distribuição Aleatória , Ratos , Receptores Androgênicos/metabolismo , Transfecção , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Recently, we had identified an unexplored pocket adjacent to the known binding site of allosteric MEK inhibitors which allowed us to design highly potent and in vivo efficacious novel inhibitors. We now report that our initial preclinical candidate, featuring a phenoxy side chain with a sulfamide capping group, displayed human carbonic anhydrase off-target activity and species-dependent blood cell accumulation, which prevented us from advancing this candidate further. Since this sulfamide MEK inhibitor displayed an exceptionally favorable PK profile with low brain penetration potential despite being highly oral bioavailable, we elected to keep the sulfamide capping group intact while taming its unwanted off-target activity by optimizing the structural surroundings. Introduction of a neighboring fluorine atom or installation of a methylene linker reduced hCA potency sufficiently, at the cost of MEK target potency. Switching to a higher fluorinated central core reinstated high MEK potency, leading to two new preclinical candidates with long half-lives, high bioavailabilities, low brain penetration potential and convincing efficacy in a K-Ras-mutated A549 xenograft model.
Assuntos
Antineoplásicos/farmacologia , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Sulfonamidas/farmacologia , Regulação Alostérica/efeitos dos fármacos , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacocinética , Disponibilidade Biológica , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Anidrases Carbônicas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Meia-Vida , Humanos , Camundongos , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacocinética , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química , Sulfonamidas/farmacocinética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Having recently identified a so-far unexplored area adjacent to the known binding site of allosteric mitogen-activated protein kinase kinase (MEK) inhibitors, we now report an extension of these studies by combining our new side chains with different MEK inhibitor cores in a modular manner. Replacement of the amide headgroup with inverse sulfonamides resulted in the identification of new MEK inhibitors with at least 10-fold higher cellular potency against K-Ras-mutated tumor cells. A selected inhibitor from this new series retained the favorable pharmacokinetic profile of its predecessor in rodent and non-rodent species and displayed significant in vivo efficacy at once-daily oral doses of 0.25-1â mg kg(-1) in a K-Ras-mutated xenograft model. The brain penetration potential of this analogue was significantly attenuated relative to PD325901. In a second series, the central fluorophenyl core was replaced by a pyridine moiety which gave rise to a similar boost in cellular potency. Most notably, analogues from this second series do not show MEK feedback phosphorylation in K-Ras-mutated A549 cells. Our results complement recent reports on the structural intricacies of MEK-Raf feedback interactions.
Assuntos
MAP Quinase Quinase 1/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Regulação Alostérica , Animais , Benzamidas/química , Benzamidas/metabolismo , Benzamidas/farmacologia , Encéfalo/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Difenilamina/análogos & derivados , Difenilamina/química , Difenilamina/metabolismo , Difenilamina/farmacologia , Feminino , Meia-Vida , Humanos , MAP Quinase Quinase 1/metabolismo , Camundongos , Camundongos Nus , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/farmacologia , Ratos , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Sulfonamidas/química , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Transplante HeterólogoRESUMO
OBJECTIVE: The objectives of the study were to evaluate the allosteric mitogen-activated protein kinase kinase (MEK) inhibitor BAY 86-9766 in monotherapy and in combination with sorafenib in orthotopic and subcutaneous hepatocellular carcinoma (HCC) models with different underlying etiologies in two species. DESIGN: Antiproliferative potential of BAY 86-9766 and synergistic effects with sorafenib were studied in several HCC cell lines. Relevant pathway signaling was studied in MH3924a cells. For in vivo testing, the HCC cells were implanted subcutaneously or orthotopically. Survival and mode of action (MoA) were analyzed. RESULTS: BAY 86-9766 exhibited potent antiproliferative activity in HCC cell lines with half-maximal inhibitory concentration values ranging from 33 to 762 nM. BAY 86-9766 was strongly synergistic with sorafenib in suppressing tumor cell proliferation and inhibiting phosphorylation of the extracellular signal-regulated kinase (ERK). BAY 86-9766 prolonged survival in Hep3B xenografts, murine Hepa129 allografts, and MH3924A rat allografts. Additionally, tumor growth, ascites formation, and serum alpha-fetoprotein levels were reduced. Synergistic effects in combination with sorafenib were shown in Huh-7, Hep3B xenografts, and MH3924A allografts. On the signaling pathway level, the combination of BAY 86-9766 and sorafenib led to inhibition of the upregulatory feedback loop toward MEK phosphorylation observed after BAY 86-9766 monotreatment. With regard to the underlying MoA, inhibition of ERK phosphorylation, tumor cell proliferation, and microvessel density was observed in vivo. CONCLUSION: BAY 86-9766 shows potent single-agent antitumor activity and acts synergistically in combination with sorafenib in preclinical HCC models. These results support the ongoing clinical development of BAY 86-9766 and sorafenib in advanced HCC.
Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Difenilamina/análogos & derivados , Neoplasias Hepáticas/tratamento farmacológico , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Niacinamida/análogos & derivados , Compostos de Fenilureia/farmacologia , Sulfonamidas/farmacologia , Aloenxertos , Regulação Alostérica , Animais , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Difenilamina/farmacologia , Difenilamina/uso terapêutico , Sinergismo Farmacológico , Feminino , Xenoenxertos , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos Nus , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Niacinamida/farmacologia , Niacinamida/uso terapêutico , Compostos de Fenilureia/uso terapêutico , Ratos , Sorafenibe , Sulfonamidas/uso terapêuticoRESUMO
Using PD325901 as a starting point for identifying novel allosteric MEK inhibitors with high cell potency and long-lasting target inhibition in vivo, truncation of its hydroxamic ester headgroup was combined with incorporation of alkyl and aryl ethers at the neighboring ring position. Whereas alkoxy side chains did not yield sufficient levels of cell potency, specifically substituted aryloxy groups allowed for high enzymatic and cellular potencies. Sulfamide 28 was identified as a highly potent MEK inhibitor with nanomolar cell potency against B-RAF (V600E) as well as Ras-mutated cell lines, high metabolic stability and resulting long half-lives. It was efficacious against B-RAF as well as K-Ras driven xenograft models and showed-despite being orally bioavailable and not a P-glycoprotein substrate-much lower brain/plasma exposure ratios than PD325901.
Assuntos
MAP Quinase Quinase Quinases/antagonistas & inibidores , MAP Quinase Quinase Quinases/química , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Regulação Alostérica , Animais , Benzamidas/química , Benzamidas/farmacologia , Difenilamina/análogos & derivados , Difenilamina/química , Difenilamina/farmacologia , Desenho de Fármacos , Camundongos , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The potential of enzyme inhibition of a drug is frequently quantified in terms of IC(50) values. Although this is a suitable quantity for reversible inhibitors, concerns arise when dealing with irreversible or mechanism-based inhibitors (MBIs). IC(50) values of MBIs are time dependent, causing serious problems when aiming at ranking different compounds with respect to their inhibitory potential. As a consequence, most studies and ranking schemes related to MBIs rely on the inhibition constant (K(I)) and the rate of enzyme inactivation (k(inact)) rather than on IC(50) values. In this article, the authors derive a novel relation between potentially time-dependent IC(50) values and K(I), k(inact) parameters for different types of inhibition. This allows for direct estimation of K(I) and k(inact) values from time-dependent IC(50) values, even without the need of additional preincubation experiments. The application of this approach is illustrated using a fluorimetric assay to access the drug-drug interaction potential associated with new chemical entities. The approach can easily be implemented using standard software tools (e.g., XLfit) and may also be suitable for applications where mechanism-based inhibition is a desired mode of action (e.g., at particular pharmacological drug targets).
Assuntos
Antagonismo de Drogas , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacocinética , Concentração Inibidora 50 , Ligação Competitiva , Citocromo P-450 CYP1A2/metabolismo , Inibidores do Citocromo P-450 CYP1A2 , Citocromo P-450 CYP3A/metabolismo , Inibidores do Citocromo P-450 CYP3A , Humanos , Modelos Químicos , Modelos Teóricos , Fatores de TempoRESUMO
Under pathophysiological conditions, alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptor activation is considered to play a key role in several disorders of the central nervous system. In the search for AMPA receptor antagonists, the synthesis and pharmacological characterization of a series of novel compounds that are structurally related to GYKI 52466 (1), a well-known selective noncompetitive AMPA receptor antagonist, was performed. In vitro, 2,3-dimethyl-6-phenyl-12H-[1,3]dioxolo[4,5-h]imidazo[1,2-c][2,3]benzodiazepine (ZK 187638, 14a) antagonized the kainate-induced currents in cultured hippocampal neurons with an IC(50) of 3.4 microM in a noncompetitive fashion. When tested in a clinically predictive rat model of acute ischemic stroke, this noncompetitive AMPA receptor antagonist significantly reduced brain infarction, indicating that it is neuroprotective after permanent focal cerebral ischemia.