RESUMO
Although RAF monomer inhibitors (type I.5, BRAF(V600)) are clinically approved for the treatment of BRAFV600-mutant melanoma, they are ineffective in non-BRAFV600 mutant cells1-3. Belvarafenib is a potent and selective RAF dimer (type II) inhibitor that exhibits clinical activity in patients with BRAFV600E- and NRAS-mutant melanomas. Here we report the first-in-human phase I study investigating the maximum tolerated dose, and assessing the safety and preliminary efficacy of belvarafenib in BRAFV600E- and RAS-mutated advanced solid tumours (NCT02405065, NCT03118817). By generating belvarafenib-resistant NRAS-mutant melanoma cells and analysing circulating tumour DNA from patients treated with belvarafenib, we identified new recurrent mutations in ARAF within the kinase domain. ARAF mutants conferred resistance to belvarafenib in both a dimer- and a kinase activity-dependent manner. Belvarafenib induced ARAF mutant dimers, and dimers containing mutant ARAF were active in the presence of inhibitor. ARAF mutations may serve as a general resistance mechanism for RAF dimer inhibitors as the mutants exhibit reduced sensitivity to a panel of type II RAF inhibitors. The combination of RAF plus MEK inhibition may be used to delay ARAF-driven resistance and suggests a rational combination for clinical use. Together, our findings reveal specific and compensatory functions for the ARAF isoform and implicate ARAF mutations as a driver of resistance to RAF dimer inhibitors.
Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Melanoma/tratamento farmacológico , Melanoma/genética , Mutação , Proteínas Proto-Oncogênicas A-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas A-raf/genética , Quinases raf/antagonistas & inibidores , Animais , Linhagem Celular , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Melanoma/patologia , Camundongos , Multimerização Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas A-raf/química , Quinases raf/químicaRESUMO
Structure-based design was utilized to optimize 6,6-diaryl substituted dihydropyrone and hydroxylactam to obtain inhibitors of lactate dehydrogenase (LDH) with low nanomolar biochemical and single-digit micromolar cellular potencies. Surprisingly the replacement of a phenyl with a pyridyl moiety in the chemical structure revealed a new binding mode for the inhibitors with subtle conformational change of the LDHA active site. This led to the identification of a potent, cell-active hydroxylactam inhibitor exhibiting an in vivo pharmacokinetic profile suitable for mouse tumor xenograft study.
Assuntos
Inibidores Enzimáticos/farmacologia , L-Lactato Desidrogenase/antagonistas & inibidores , Lactamas/farmacologia , Animais , Linhagem Celular , Cães , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Humanos , L-Lactato Desidrogenase/metabolismo , Lactamas/química , Camundongos , Microssomos Hepáticos/química , Microssomos Hepáticos/metabolismo , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
Metabolic reprogramming in tumors represents a potential therapeutic target. Herein we used shRNA depletion and a novel lactate dehydrogenase (LDHA) inhibitor, GNE-140, to probe the role of LDHA in tumor growth in vitro and in vivo. In MIA PaCa-2 human pancreatic cells, LDHA inhibition rapidly affected global metabolism, although cell death only occurred after 2 d of continuous LDHA inhibition. Pancreatic cell lines that utilize oxidative phosphorylation (OXPHOS) rather than glycolysis were inherently resistant to GNE-140, but could be resensitized to GNE-140 with the OXPHOS inhibitor phenformin. Acquired resistance to GNE-140 was driven by activation of the AMPK-mTOR-S6K signaling pathway, which led to increased OXPHOS, and inhibitors targeting this pathway could prevent resistance. Thus, combining an LDHA inhibitor with compounds targeting the mitochondrial or AMPK-S6K signaling axis may not only broaden the clinical utility of LDHA inhibitors beyond glycolytically dependent tumors but also reduce the emergence of resistance to LDHA inhibition.
Assuntos
Plasticidade Celular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , L-Lactato Desidrogenase/antagonistas & inibidores , Piridonas/farmacologia , Tiofenos/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Humanos , L-Lactato Desidrogenase/metabolismo , Modelos Moleculares , Estrutura Molecular , Piridonas/química , Relação Estrutura-Atividade , Tiofenos/químicaRESUMO
The treatment of epidermal growth factor receptor (EGFR)-driven non-small cell lung cancers with the T790M resistance mutation remains a significant unmet medical need. We report the identification of 4-aminoindazolyl-dihydrofuro[3,4-d]pyrimidines as non-covalent inhibitors of EGFR, with excellent activity against the T790M resistance double mutants and initial single activating mutants. Using an optimization strategy focused on structure-based design and improving PK properties through metabolite identification, we obtained advanced leads with high oral exposure.
Assuntos
Receptores ErbB/antagonistas & inibidores , Furanos/farmacologia , Indazóis/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Acrilamidas/farmacologia , Compostos de Anilina/farmacologia , Animais , Sítios de Ligação , Cristalografia por Raios X , Cães , Receptores ErbB/química , Cloridrato de Erlotinib/farmacologia , Furanos/síntese química , Furanos/química , Furanos/farmacocinética , Hepatócitos/metabolismo , Ensaios de Triagem em Larga Escala , Humanos , Ligação de Hidrogênio , Indazóis/síntese química , Indazóis/química , Indazóis/farmacocinética , Camundongos , Microssomos Hepáticos/metabolismo , Mutação Puntual , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacocinética , Pirimidinas/síntese química , Pirimidinas/química , Pirimidinas/farmacocinética , RatosRESUMO
Activating mutations in KRAS and BRAF are found in more than 30% of all human tumours and 40% of melanoma, respectively, thus targeting this pathway could have broad therapeutic effects. Small molecule ATP-competitive RAF kinase inhibitors have potent antitumour effects on mutant BRAF(V600E) tumours but, in contrast to mitogen-activated protein kinase kinase (MEK) inhibitors, are not potent against RAS mutant tumour models, despite RAF functioning as a key effector downstream of RAS and upstream of MEK. Here we show that ATP-competitive RAF inhibitors have two opposing mechanisms of action depending on the cellular context. In BRAF(V600E) tumours, RAF inhibitors effectively block the mitogen-activated protein kinase (MAPK) signalling pathway and decrease tumour growth. Notably, in KRAS mutant and RAS/RAF wild-type tumours, RAF inhibitors activate the RAF-MEK-ERK pathway in a RAS-dependent manner, thus enhancing tumour growth in some xenograft models. Inhibitor binding activates wild-type RAF isoforms by inducing dimerization, membrane localization and interaction with RAS-GTP. These events occur independently of kinase inhibition and are, instead, linked to direct conformational effects of inhibitors on the RAF kinase domain. On the basis of these findings, we demonstrate that ATP-competitive kinase inhibitors can have opposing functions as inhibitors or activators of signalling pathways, depending on the cellular context. Furthermore, this work provides new insights into the therapeutic use of ATP-competitive RAF inhibitors.
Assuntos
Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neoplasias/patologia , Inibidores de Proteínas Quinases/farmacologia , Quinases raf/antagonistas & inibidores , Quinases raf/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Benzamidas/farmacologia , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Difenilamina/análogos & derivados , Difenilamina/farmacologia , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Indenos/farmacologia , Indóis/farmacologia , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Neoplasias/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Multimerização Proteica , Estrutura Terciária de Proteína , Transporte Proteico/efeitos dos fármacos , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/química , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas c-raf/deficiência , Proteínas Proto-Oncogênicas c-raf/genética , Proteínas Proto-Oncogênicas c-raf/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , Pirazóis/farmacologia , Sulfonamidas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , Quinases raf/química , Quinases raf/genética , Proteínas ras/genética , Proteínas ras/metabolismoRESUMO
Optimization of 5-(2,6-dichlorophenyl)-3-hydroxy-2-mercaptocyclohex-2-enone using structure-based design strategies resulted in inhibitors with considerable improvement in biochemical potency against human lactate dehydrogenase A (LDHA). These potent inhibitors were typically selective for LDHA over LDHB isoform (410 fold) and other structurally related malate dehydrogenases, MDH1 and MDH2 (>500 fold). An X-ray crystal structure of enzymatically most potent molecule bound to LDHA revealed two additional interactions associated with enhanced biochemical potency.
Assuntos
Inibidores Enzimáticos/síntese química , L-Lactato Desidrogenase/antagonistas & inibidores , Animais , Cristalografia por Raios X , Cães , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , L-Lactato Desidrogenase/metabolismo , Células Madin Darby de Rim CaninoRESUMO
A series of 3,6-disubstituted dihydropyrones were identified as inhibitors of human lactate dehydrogenase (LDH)-A. Structure activity relationships were explored and a series of 6,6-spiro analogs led to improvements in LDHA potency (IC50 <350 nM). An X-ray crystal structure of an improved compound bound to human LDHA was obtained and it illustrated additional opportunities to enhance the potency of these compounds, resulting in the identification of 51 (IC50=30 nM).
Assuntos
Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , L-Lactato Desidrogenase/antagonistas & inibidores , Pironas/síntese química , Pironas/farmacologia , Sítios de Ligação , Cristalografia por Raios X , Humanos , L-Lactato Desidrogenase/metabolismo , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
Checkpoint kinase 1 (ChK1) is activated in response to DNA damage, acting to temporarily block cell cycle progression and allow for DNA repair. It is envisaged that inhibition of ChK1 will sensitize tumor cells to treatment with DNA-damaging therapies, and may enhance the therapeutic window. High throughput screening identified carboxylate-containing diarylpyrazines as a prominent hit series, but with limited biochemical potency and no cellular activity. Through a series of SAR investigations and X-ray crystallographic analysis the critical role of polar contacts with conserved waters in the kinase back pocket was established. Structure-based design, guided by in silico modeling, transformed the series to better satisfy these contacts and the novel 1,7-diazacarbazole class of inhibitors was discovered. Here we present the genesis of this novel series and the identification of GNE-783, a potent, selective and orally bioavailable inhibitor of ChK1.
Assuntos
Compostos Aza/química , Carbazóis/química , Carbolinas/farmacologia , Descoberta de Drogas , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/química , Administração Oral , Animais , Carbolinas/administração & dosagem , Carbolinas/síntese química , Carbolinas/farmacocinética , Quinase 1 do Ponto de Checagem , Cristalografia por Raios X , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Sinergismo Farmacológico , Humanos , Camundongos , Conformação Proteica , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacocinética , Ratos , Relação Estrutura-Atividade , Distribuição Tecidual , GencitabinaRESUMO
A novel class of 3-hydroxy-2-mercaptocyclohex-2-enone-containing inhibitors of human lactate dehydrogenase (LDH) was identified through a high-throughput screening approach. Biochemical and surface plasmon resonance experiments performed with a screening hit (LDHA IC50=1.7 µM) indicated that the compound specifically associated with human LDHA in a manner that required simultaneous binding of the NADH co-factor. Structural variation of this screening hit resulted in significant improvements in LDHA biochemical inhibition activity (best IC50=0.18 µM). Two crystal structures of optimized compounds bound to human LDHA were obtained and explained many of the observed structure-activity relationships. In addition, an optimized inhibitor exhibited good pharmacokinetic properties after oral administration to rats (F=45%).
Assuntos
Cicloexanonas/farmacologia , Inibidores Enzimáticos/farmacologia , L-Lactato Desidrogenase/antagonistas & inibidores , Compostos de Sulfidrila/farmacologia , Administração Oral , Animais , Cicloexanonas/administração & dosagem , Cicloexanonas/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Ensaios de Triagem em Larga Escala , Humanos , L-Lactato Desidrogenase/metabolismo , Modelos Moleculares , Estrutura Molecular , Ratos , Relação Estrutura-Atividade , Compostos de Sulfidrila/administração & dosagem , Compostos de Sulfidrila/químicaRESUMO
A 2-amino-5-aryl-pyrazine was identified as an inhibitor of human lactate dehydrogenase A (LDHA) via a biochemical screening campaign. Biochemical and biophysical experiments demonstrated that the compound specifically interacted with human LDHA. Structural variation of the screening hit resulted in improvements in LDHA biochemical inhibition and pharmacokinetic properties. A crystal structure of an improved compound bound to human LDHA was also obtained and it explained many of the observed structure-activity relationships.
Assuntos
Inibidores Enzimáticos/química , L-Lactato Desidrogenase/antagonistas & inibidores , Pirazinas/química , Animais , Sítios de Ligação , Cristalografia por Raios X , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacocinética , Meia-Vida , Humanos , L-Lactato Desidrogenase/metabolismo , Masculino , Microssomos Hepáticos/metabolismo , Estrutura Terciária de Proteína , Pirazinas/síntese química , Pirazinas/farmacocinética , Ratos , Ratos Sprague-Dawley , Relação Estrutura-AtividadeRESUMO
A novel 2-thio-6-oxo-1,6-dihydropyrimidine-containing inhibitor of human lactate dehydrogenase (LDH) was identified by high-throughput screening (IC50=8.1 µM). Biochemical, surface plasmon resonance, and saturation transfer difference NMR experiments indicated that the compound specifically associated with human LDHA in a manner that required simultaneous binding of the NADH co-factor. Structural variation of the screening hit resulted in significant improvements in LDHA biochemical inhibition activity (best IC50=0.48 µM). A crystal structure of an optimized compound bound to human LDHA was obtained and explained many of the observed structure-activity relationships.
Assuntos
Inibidores Enzimáticos/química , L-Lactato Desidrogenase/antagonistas & inibidores , Pirimidinas/química , Sítios de Ligação , Cristalografia por Raios X , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/metabolismo , Humanos , Ligação de Hidrogênio , L-Lactato Desidrogenase/metabolismo , Espectroscopia de Ressonância Magnética , NAD/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Pirimidinas/síntese química , Pirimidinas/metabolismo , Relação Estrutura-Atividade , Ressonância de Plasmônio de SuperfícieRESUMO
Targeted degradation of proteins by chimeric heterobifunctional degraders has emerged as a major drug discovery paradigm. Despite the increased interest in this approach, the criteria dictating target protein degradation by a degrader remain poorly understood, and potent target engagement by a degrader does not strongly correlate with target degradation. In this study, we present the biochemical characterization of an epidermal growth factor receptor (EGFR) degrader that potently binds both wild-type and mutant EGFR, but only degrades EGFR mutant variants. Mechanistic studies reveal that ternary complex half-life strongly correlates with processive ubiquitination with purified components and mutant-selective degradation in cells. We present cryoelectron microscopy and hydrogen-deuterium exchange mass spectroscopy data on wild-type and mutant EGFR ternary complexes, which demonstrate that potent target degradation can be achieved in the absence of stable compound-induced protein-protein interactions. These results highlight the importance of considering target conformation during degrader development as well as leveraging heterobifunctional ligand binding kinetics to achieve robust target degradation.
RESUMO
KRAS, which is mutated in â¼30% of all cancers, activates the RAF-MEK-ERK signaling cascade. CRAF is required for growth of KRAS mutant lung tumors, but the requirement for CRAF kinase activity is unknown. Here, we show that subsets of KRAS mutant tumors are dependent on CRAF for growth. Kinase-dead but not dimer-defective CRAF rescues growth inhibition, suggesting that dimerization but not kinase activity is required. Quantitative proteomics demonstrates increased levels of CRAF:ARAF dimers in KRAS mutant cells, and depletion of both CRAF and ARAF rescues the CRAF-loss phenotype. Mechanistically, CRAF depletion causes sustained ERK activation and induction of cell-cycle arrest, while treatment with low-dose MEK or ERK inhibitor rescues the CRAF-loss phenotype. Our studies highlight the role of CRAF in regulating MAPK signal intensity to promote tumorigenesis downstream of mutant KRAS and suggest that disrupting CRAF dimerization or degrading CRAF may have therapeutic benefit.
Assuntos
Carcinogênese/metabolismo , Dimerização , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Animais , Carcinogênese/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Fosforilação/fisiologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Proteínas ras/genéticaRESUMO
Optimization of a series of aryl urea RAF inhibitors led to the identification of type II pan-RAF inhibitor GNE-0749 (7), which features a fluoroquinazolinone hinge-binding motif. By minimizing reliance on common polar hinge contacts, this hinge binder allows for a greater contribution of RAF-specific residue interactions, resulting in exquisite kinase selectivity. Strategic substitution of fluorine at the C5 position efficiently masked the adjacent polar NH functionality and increased solubility by impeding a solid-state conformation associated with stronger crystal packing of the molecule. The resulting improvements in permeability and solubility enabled oral dosing of 7. In vivo evaluation of 7 in combination with the MEK inhibitor cobimetinib demonstrated synergistic pathway inhibition and significant tumor growth inhibition in a KRAS mutant xenograft mouse model.
Assuntos
Neoplasias/tratamento farmacológico , Compostos de Fenilureia/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Quinazolinonas/uso terapêutico , Quinases raf/antagonistas & inibidores , Animais , Azetidinas/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Cães , Combinação de Medicamentos , Sinergismo Farmacológico , Feminino , Humanos , Células Madin Darby de Rim Canino , Camundongos Nus , Estrutura Molecular , Mutação , Compostos de Fenilureia/química , Compostos de Fenilureia/metabolismo , Piperidinas/uso terapêutico , Ligação Proteica , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/metabolismo , Quinazolinonas/química , Quinazolinonas/metabolismo , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto , Quinases raf/genética , Quinases raf/metabolismoRESUMO
Structure-based optimization of a set of aryl urea RAF inhibitors has led to the identification of Type II pan-RAF inhibitor GNE-9815 (7), which features a unique pyrido[2,3-d]pyridazin-8(7H)-one hinge-binding motif. With minimal polar hinge contacts, the pyridopyridazinone hinge binder moiety affords exquisite kinase selectivity in a lipophilic efficient manner. The improved physicochemical properties of GNE-9815 provided a path for oral dosing without enabling formulations. In vivo evaluation of GNE-9815 in combination with the MEK inhibitor cobimetinib demonstrated synergistic MAPK pathway modulation in an HCT116 xenograft mouse model. To the best of our knowledge, GNE-9815 is among the most highly kinase-selective RAF inhibitors reported to date.
RESUMO
Targeting KRAS mutant tumors through inhibition of individual downstream pathways has had limited clinical success. Here we report that RAF inhibitors exhibit little efficacy in KRAS mutant tumors. In combination drug screens, MEK and PI3K inhibitors synergized with pan-RAF inhibitors through an RAS-GTP-dependent mechanism. Broad cell line profiling with RAF/MEK inhibitor combinations revealed synergistic efficacy in KRAS mutant and wild-type tumors, with KRASG13D mutants exhibiting greater synergy versus KRASG12 mutant tumors. Mechanistic studies demonstrate that MEK inhibition induced RAS-GTP levels, RAF dimerization and RAF kinase activity resulting in MEK phosphorylation in synergistic tumor lines regardless of KRAS status. Taken together, our studies uncover a strategy to rewire KRAS mutant tumors to confer sensitivity to RAF kinase inhibition.
Assuntos
Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas p21(ras)/efeitos dos fármacos , Linhagem Celular Tumoral , Guanosina Trifosfato/metabolismo , Humanos , Mutação/efeitos dos fármacos , Mutação/genética , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas B-raf/efeitos dos fármacos , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas ras/efeitos dos fármacos , Proteínas ras/genéticaRESUMO
Activating mutations in protein kinases drive many cancers. While how recurring point mutations affect kinase activity has been described, the effect of in-frame deletions is not well understood. We show that oncogenic deletions within the ß3-αC loop of HER2 and BRAF are analogous to the recurrent EGFR exon 19 deletions. We identify pancreatic carcinomas with BRAF deletions mutually exclusive with KRAS mutations. Crystal structures of BRAF deletions reveal the truncated loop restrains αC in an active "in" conformation, imparting resistance to inhibitors like vemurafenib that bind the αC "out" conformation. Characterization of loop length explains the prevalence of five amino acid deletions in BRAF, EGFR, and HER2 and highlights the importance of this region for kinase activity and inhibitor efficacy.
Assuntos
Genes erbB-1 , Genes erbB-2 , Mutação , Proteínas de Neoplasias/genética , Neoplasias/genética , Proteínas Proto-Oncogênicas B-raf/genética , Sequência de Aminoácidos , Substituição de Aminoácidos , Antineoplásicos/farmacologia , Pareamento de Bases/genética , Sequência Conservada , Dimerização , Resistencia a Medicamentos Antineoplásicos/genética , Ativação Enzimática/genética , Receptores ErbB/metabolismo , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Neoplasias/enzimologia , Conformação Proteica , Mapeamento de Interação de Proteínas , Inibidores de Proteínas Quinases/farmacologia , Estrutura Secundária de Proteína , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/metabolismo , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Relação Estrutura-AtividadeRESUMO
The rapid advancement of a series of noncovalent inhibitors of T790M mutants of EGFR is discussed. The optimization of pyridone 1, a nonselective high-throughput screening hit, to potent molecules with high levels of selectivity over wtEGFR and the broader kinome is described herein.
RESUMO
A series of trisubstituted hydroxylactams was identified as potent enzymatic and cellular inhibitors of human lactate dehydrogenase A. Utilizing structure-based design and physical property optimization, multiple inhibitors were discovered with <10 µM lactate IC50 in a MiaPaca2 cell line. Optimization of the series led to 29, a potent cell active molecule (MiaPaca2 IC50 = 0.67 µM) that also possessed good exposure when dosed orally to mice.
RESUMO
Inhibitors targeting the activating mutants of the epidermal growth factor receptor (EGFR) have found success in the treatment of EGFR mutant positive non-small-cell lung cancer. A secondary point mutation (T790M) in the inhibitor binding site has been linked to the acquired resistance against those first generation therapeutics. Herein, we describe the lead optimization of a series of reversible, pan-mutant (L858R, del746-750, T790M/L858R, and T790M/del746-750) EGFR inhibitors. By use of a noncovalent double mutant (T790M/L858R and T790M/del746-750) selective EGFR inhibitor (2) as a starting point, activities against the single mutants (L858R and del746-750) were introduced through a series of structure-guided modifications. The in vitro ADME-PK properties of the lead molecules were further optimized through a number of rational structural changes. The resulting inhibitor (21) exhibited excellent cellular activity against both the single and double mutants of EGFR, demonstrating target engagement in vivo and ADME-PK properties that are suitable for further evaluation. The reversible, noncovalent inhibitors described complement the covalent pan-mutant EGFR inhibitors that have shown encouraging results in recent clinical trials.