RESUMO
Mutations at the arginine residue (R132) in isocitrate dehydrogenase 1 (IDH1) are frequently identified in various human cancers. Inhibition of mutant IDH1 (mIDH1) with small molecules has been clinically validated as a promising therapeutic treatment for acute myeloid leukemia and multiple solid tumors. Herein, we report the discovery and optimization of a series of quinolinones to provide potent and orally bioavailable mIDH1 inhibitors with selectivity over wild-type IDH1. The X-ray structure of an early lead 24 in complex with mIDH1-R132H shows that the inhibitor unexpectedly binds to an allosteric site. Efforts to improve the in vitro and in vivo absorption, distribution, metabolism, and excretion (ADME) properties of 24 yielded a preclinical candidate 63. The detailed preclinical ADME and pharmacology studies of 63 support further development of quinolinone-based mIDH1 inhibitors as therapeutic agents in human trials.
Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Isocitrato Desidrogenase/antagonistas & inibidores , Quinolonas/química , Quinolonas/farmacologia , Sítio Alostérico/efeitos dos fármacos , Animais , Disponibilidade Biológica , Linhagem Celular Tumoral , Cristalografia por Raios X , Cães , Descoberta de Drogas , Inibidores Enzimáticos/farmacocinética , Feminino , Humanos , Isocitrato Desidrogenase/química , Isocitrato Desidrogenase/genética , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Mutação Puntual , Quinolonas/farmacocinéticaRESUMO
The discovery, structure-activity relationships, and optimization of a novel class of fatty acid synthase (FASN) inhibitors is reported. High throughput screening identified a series of substituted piperazines with structural features that enable interactions with many of the potency-driving regions of the FASN KR domain binding site. Derived from this series was FT113, a compound with potent biochemical and cellular activity, which translated into excellent activity in in vivo models.
Assuntos
Ácido Graxo Sintases/antagonistas & inibidores , Piperazinas/química , Administração Oral , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Ácido Graxo Sintases/metabolismo , Meia-Vida , Humanos , Malonil Coenzima A/metabolismo , Camundongos , Camundongos Nus , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Piperazinas/administração & dosagem , Piperazinas/farmacocinética , Piperazinas/farmacologia , Estrutura Terciária de Proteína , Ratos , Relação Estrutura-AtividadeRESUMO
Ubiquitination controls the stability of most cellular proteins, and its deregulation contributes to human diseases including cancer. Deubiquitinases remove ubiquitin from proteins, and their inhibition can induce the degradation of selected proteins, potentially including otherwise 'undruggable' targets. For example, the inhibition of ubiquitin-specific protease 7 (USP7) results in the degradation of the oncogenic E3 ligase MDM2, and leads to re-activation of the tumour suppressor p53 in various cancers. Here we report that two compounds, FT671 and FT827, inhibit USP7 with high affinity and specificity in vitro and within human cells. Co-crystal structures reveal that both compounds target a dynamic pocket near the catalytic centre of the auto-inhibited apo form of USP7, which differs from other USP deubiquitinases. Consistent with USP7 target engagement in cells, FT671 destabilizes USP7 substrates including MDM2, increases levels of p53, and results in the transcription of p53 target genes, induction of the tumour suppressor p21, and inhibition of tumour growth in mice.
Assuntos
Piperidinas/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Peptidase 7 Específica de Ubiquitina/antagonistas & inibidores , Animais , Apoenzimas/antagonistas & inibidores , Apoenzimas/química , Apoenzimas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Feminino , Humanos , Camundongos , Modelos Moleculares , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Neoplasias/patologia , Piperidinas/síntese química , Proteínas Proto-Oncogênicas c-mdm2/química , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Pirazóis/síntese química , Pirimidinas/síntese química , Especificidade por Substrato , Transcrição Gênica/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Peptidase 7 Específica de Ubiquitina/química , Peptidase 7 Específica de Ubiquitina/metabolismo , Ubiquitinação/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
NAMPT inhibitors may show potential as therapeutics for oncology. Throughout our NAMPT inhibitor program, we found that exposed pyridines or related heterocyclic systems in the left-hand portion of the inhibitors are necessary pharmacophores for potent cellular NAMPT inhibition. However, when combined with a benzyl group in the center of the inhibitors, such pyridine-like moieties also led to consistent and potent inhibition of CYP2C9. In an attempt to reduce CYP2C9 inhibition, a parallel synthesis approach was used to identify central benzyl group replacements with increased Fsp3. A spirocyclic central motif was thus discovered that was combined with left-hand pyridines (or pyridine-like systems) to provide cellularly potent NAMPT inhibitors with minimal CYP2C9 inhibition. Further optimization of potency and ADME properties led to the discovery of compound 68, a highly potent NAMPT inhibitor with outstanding efficacy in a mouse tumor xenograft model and lacking measurable CYP2C9 inhibition at the concentrations tested.
Assuntos
Citocromo P-450 CYP2C9/metabolismo , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Piridinas/química , Piridinas/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Inibidores do Citocromo P-450 CYP2C9/química , Inibidores do Citocromo P-450 CYP2C9/farmacologia , Descoberta de Drogas , Inibidores Enzimáticos/uso terapêutico , Feminino , Humanos , Camundongos , Camundongos Nus , Modelos Moleculares , Neoplasias/tratamento farmacológico , Nicotinamida Fosforribosiltransferase/metabolismo , Piridinas/uso terapêuticoRESUMO
Herein we report the optimization efforts to ameliorate the potent CYP3A4 time-dependent inhibition (TDI) and low aqueous solubility exhibited by a previously identified lead compound from our NAMPT inhibitor program (1, GNE-617). Metabolite identification studies pinpointed the imidazopyridine moiety present in 1 as the likely source of the TDI signal, and replacement with other bicyclic systems was found to reduce or eliminate the TDI finding. A strategy of reducing the number of aromatic rings and/or lowering cLogD7.4 was then employed to significantly improve aqueous solubility. These efforts culminated in the discovery of 42, a compound with no evidence of TDI, improved aqueous solubility, and robust efficacy in tumor xenograft studies.
Assuntos
Citocromo P-450 CYP3A/química , Inibidores Enzimáticos/química , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Citocromo P-450 CYP3A/metabolismo , Inibidores do Citocromo P-450 CYP3A/química , Inibidores do Citocromo P-450 CYP3A/farmacocinética , Inibidores do Citocromo P-450 CYP3A/toxicidade , Cães , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/uso terapêutico , Feminino , Meia-Vida , Humanos , Cinética , Células Madin Darby de Rim Canino , Camundongos , Camundongos Nus , Simulação de Dinâmica Molecular , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Nicotinamida Fosforribosiltransferase/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Pirimidinas/química , Pirimidinas/uso terapêutico , Pirimidinas/toxicidade , Solubilidade , Relação Estrutura-Atividade , Termodinâmica , Transplante Heterólogo , Água/químicaRESUMO
Inhibiting NAD biosynthesis by blocking the function of nicotinamide phosphoribosyl transferase (NAMPT) is an attractive therapeutic strategy for targeting tumor metabolism. However, the development of drug resistance commonly limits the efficacy of cancer therapeutics. This study identifies mutations in NAMPT that confer resistance to a novel NAMPT inhibitor, GNE-618, in cell culture and in vivo, thus demonstrating that the cytotoxicity of GNE-618 is on target. We determine the crystal structures of six NAMPT mutants in the apo form and in complex with various inhibitors and use cellular, biochemical and structural data to elucidate two resistance mechanisms. One is the surprising finding of allosteric modulation by mutation of residue Ser165, resulting in unwinding of an α-helix that binds the NAMPT substrate 5-phosphoribosyl-1-pyrophosphate (PRPP). The other mechanism is orthosteric blocking of inhibitor binding by mutations of Gly217. Furthermore, by evaluating a panel of diverse small molecule inhibitors, we unravel inhibitor structure activity relationships on the mutant enzymes. These results provide valuable insights into the design of next generation NAMPT inhibitors that offer improved therapeutic potential by evading certain mechanisms of resistance.
Assuntos
Antineoplásicos/farmacologia , Citocinas/antagonistas & inibidores , Citocinas/química , Resistencia a Medicamentos Antineoplásicos , Inibidores Enzimáticos/farmacologia , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Nicotinamida Fosforribosiltransferase/química , Domínio Catalítico , Linhagem Celular Tumoral , Citocinas/genética , Humanos , Modelos Moleculares , Mutação , Nicotinamida Fosforribosiltransferase/genéticaRESUMO
Potent, trans-2-(pyridin-3-yl)cyclopropanecarboxamide-containing inhibitors of the human nicotinamide phosphoribosyltransferase (NAMPT) enzyme were identified using fragment-based screening and structure-based design techniques. Multiple crystal structures were obtained of initial fragment leads, and this structural information was utilized to improve the biochemical and cell-based potency of the associated molecules. Many of the optimized compounds exhibited nanomolar antiproliferative activities against human tumor lines in in vitro cell culture experiments. In a key example, a fragment lead (13, KD = 51 µM) was elaborated into a potent NAMPT inhibitor (39, NAMPT IC50 = 0.0051 µM, A2780 cell culture IC50 = 0.000 49 µM) which demonstrated encouraging in vivo efficacy in an HT-1080 mouse xenograft tumor model.
Assuntos
Amidas/síntese química , Antineoplásicos/síntese química , Ciclopropanos/síntese química , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Piridinas/síntese química , Sulfonas/síntese química , Amidas/química , Amidas/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cristalografia por Raios X , Ciclopropanos/química , Ciclopropanos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Modelos Moleculares , Transplante de Neoplasias , Conformação Proteica , Piridinas/química , Piridinas/farmacologia , Estereoisomerismo , Relação Estrutura-Atividade , Sulfonas/química , Sulfonas/farmacologiaRESUMO
A co-crystal structure of amide-containing compound (4) in complex with the nicotinamide phosphoribosyltransferase (Nampt) protein and molecular modeling were utilized to design and discover a potent novel cyanoguanidine-containing inhibitor bearing a sulfone moiety (5, Nampt Biochemical IC50=2.5nM, A2780 cell proliferation IC50=9.7nM). Further SAR exploration identified several additional cyanoguanidine-containing compounds with high potency and good microsomal stability. Among these, compound 15 was selected for in vivo profiling and demonstrated good oral exposure in mice. It also exhibited excellent in vivo antitumor efficacy when dosed orally in an A2780 ovarian tumor xenograft model. The co-crystal structure of this compound in complex with the NAMPT protein was also determined.
Assuntos
Antineoplásicos/farmacologia , Citocinas/antagonistas & inibidores , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Guanidinas/farmacologia , Neoplasias Experimentais/tratamento farmacológico , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Neoplasias Ovarianas/tratamento farmacológico , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Feminino , Guanidinas/administração & dosagem , Guanidinas/química , Humanos , Camundongos , Modelos Moleculares , Estrutura Molecular , Nicotinamida Fosforribosiltransferase/metabolismo , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Potent, 1H-pyrazolo[3,4-b]pyridine-containing inhibitors of the human nicotinamide phosphoribosyltransferase (NAMPT) enzyme were identified using structure-based design techniques. Many of these compounds exhibited nanomolar antiproliferation activities against human tumor lines in in vitro cell culture experiments, and a representative example (compound 26) demonstrated encouraging in vivo efficacy in a mouse xenograft tumor model derived from the A2780 cell line. This molecule also exhibited reduced rat retinal exposures relative to a previously studied imidazo-pyridine-containing NAMPT inhibitor. Somewhat surprisingly, compound 26 was only weakly active in vitro against mouse and monkey tumor cell lines even though it was a potent inhibitor of NAMPT enzymes derived from these species. The compound also exhibited only minimal effects on in vivo NAD levels in mice, and these changes were considerably less profound than those produced by an imidazo-pyridine-containing NAMPT inhibitor. The crystal structures of compound 26 and the corresponding PRPP-derived ribose adduct in complex with NAMPT were also obtained.
Assuntos
Amidas/química , Ácidos Carboxílicos/química , Citocinas/antagonistas & inibidores , Inibidores Enzimáticos/química , Niacinamida/análogos & derivados , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Pirazóis/química , Piridinas/química , Sulfonas/química , Amidas/síntese química , Amidas/farmacocinética , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Citocinas/metabolismo , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacocinética , Feminino , Meia-Vida , Haplorrinos , Humanos , Camundongos , Camundongos Nus , NAD/metabolismo , Niacinamida/sangue , Niacinamida/química , Niacinamida/farmacocinética , Nicotinamida Fosforribosiltransferase/metabolismo , Estrutura Terciária de Proteína , Pirazóis/sangue , Pirazóis/farmacocinética , Ratos , Retina/efeitos dos fármacos , Retina/metabolismo , Relação Estrutura-Atividade , Sulfonas/sangue , Sulfonas/farmacocinética , Transplante HeterólogoRESUMO
Potent nicotinamide phosphoribosyltransferase (NAMPT) inhibitors containing 2,3-dihydro-1H-pyrrolo[3,4-c]pyridine-derived ureas were identified using structure-based design techniques. The new compounds displayed improved aqueous solubilities, determined using a high-throughput solubility assessment, relative to previously disclosed urea and amide-containing NAMPT inhibitors. An optimized 2,3-dihydro-1H-pyrrolo[3,4-c]pyridine-derived compound exhibited potent anti-NAMPT activity (18; BC NAMPT IC50 = 11 nM; PC-3 antiproliferative IC50 = 36 nM), satisfactory mouse PK properties, and was efficacious in a PC-3 mouse xenograft model. The crystal structure of another optimized compound (29; NAMPT IC50 = 10nM; A2780 antiproliferative IC50 = 7 nM) in complex with the NAMPT protein was also determined.
Assuntos
Antineoplásicos/química , Antineoplásicos/uso terapêutico , Citocinas/antagonistas & inibidores , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Piridinas/química , Piridinas/uso terapêutico , Ureia/química , Ureia/uso terapêutico , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Citocinas/metabolismo , Humanos , Camundongos , Camundongos Nus , Modelos Moleculares , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Nicotinamida Fosforribosiltransferase/metabolismo , Piridinas/farmacocinética , Piridinas/farmacologia , Relação Estrutura-Atividade , Ureia/farmacocinética , Ureia/farmacologiaRESUMO
Crystal structures of several urea- and thiourea-derived compounds in complex with the nicotinamide phosphoribosyltransferase (Nampt) protein were utilized to design a potent amide-containing inhibitor bearing an aza-indole moiety (7, Nampt BC IC50 = 9.0 nM, A2780 cell proliferation IC50 = 10 nM). The Nampt-7 cocrystal structure was subsequently obtained and enabled the design of additional amide-containing inhibitors which incorporated various other fused 6,5-heterocyclic moieties and biaryl sulfone or sulfonamide motifs. Additional modifications of these molecules afforded many potent biaryl sulfone-containing Nampt inhibitors which also exhibited favorable in vitro ADME properties (microsomal and hepatocyte stability, MDCK permeability, plasma protein binding). An optimized compound (58) was a potent inhibitor of multiple cancer cell lines (IC50 <10 nM vs U251, HT1080, PC3, MiaPaCa2, and HCT116 lines), displayed acceptable mouse PK properties (F = 41%, CL = 52.4 mL/min/kg), and exhibited robust efficacy in a U251 mouse xenograft model.
Assuntos
Descoberta de Drogas , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Animais , Inibidores Enzimáticos/farmacocinética , Espectroscopia de Ressonância Magnética , Camundongos , Camundongos Nus , Modelos Moleculares , Estrutura Molecular , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Potent, reversible inhibition of the cytochrome P450 CYP2C9 isoform was observed in a series of urea-containing nicotinamide phosphoribosyltransferase (NAMPT) inhibitors. This unwanted property was successfully removed from the described inhibitors through a combination of structure-based design and medicinal chemistry activities. An optimized compound which did not inhibit CYP2C9 exhibited potent anti-NAMPT activity (17; BC NAMPT IC50=3 nM; A2780 antiproliferative IC50=70 nM), good mouse PK properties, and was efficacious in an A2780 mouse xenograft model. The crystal structure of this compound in complex with the NAMPT protein is also described.
Assuntos
Hidrocarboneto de Aril Hidroxilases/antagonistas & inibidores , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Ureia/análogos & derivados , Ureia/farmacologia , Animais , Hidrocarboneto de Aril Hidroxilases/química , Hidrocarboneto de Aril Hidroxilases/metabolismo , Citocromo P-450 CYP2C9 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Nicotinamida Fosforribosiltransferase/química , Nicotinamida Fosforribosiltransferase/metabolismo , Ureia/síntese químicaRESUMO
Nicotinamide phosphoribosyltransferase (Nampt) is a promising anticancer target. Virtual screening identified a thiourea analogue, compound 5, as a novel highly potent Nampt inhibitor. Guided by the cocrystal structure of 5, SAR exploration revealed that the corresponding urea compound 7 exhibited similar potency with an improved solubility profile. These studies also indicated that a 3-pyridyl group was the preferred substituent at one inhibitor terminus and also identified a urea moiety as the optimal linker to the remainder of the inhibitor structure. Further SAR optimization of the other inhibitor terminus ultimately yielded compound 50 as a urea-containing Nampt inhibitor which exhibited excellent biochemical and cellular potency (enzyme IC50 = 0.007 µM; A2780 IC50 = 0.032 µM). Compound 50 also showed excellent in vivo antitumor efficacy when dosed orally in an A2780 ovarian tumor xenograft model (TGI of 97% was observed on day 17).
Assuntos
Descoberta de Drogas , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Ureia/química , Ureia/farmacologia , Humanos , Concentração Inibidora 50 , Nicotinamida Fosforribosiltransferase/química , Conformação Proteica , Relação Estrutura-AtividadeRESUMO
Homeostasis under hypoxic conditions is maintained through a coordinated transcriptional response mediated by the hypoxia-inducible factor (HIF) pathway and requires coactivation by the CBP and p300 transcriptional coactivators. Through a target-based high-throughput screen, we identified chetomin as a disrupter of HIF binding to p300. At a molecular level, chetomin disrupts the structure of the CH1 domain of p300 and precludes its interaction with HIF, thereby attenuating hypoxia-inducible transcription. Systemic administration of chetomin inhibited hypoxia-inducible transcription within tumors and inhibited tumor growth. These results demonstrate a therapeutic window for pharmacological attenuation of HIF activity and further establish the feasibility of disrupting a signal transduction pathway by targeting the function of a transcriptional coactivator with a small molecule.
Assuntos
Antibacterianos/farmacologia , Proteínas de Ligação a DNA , Proteínas Nucleares/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica/efeitos dos fármacos , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto , Carcinoma Hepatocelular/patologia , Hipóxia Celular/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Neoplasias do Colo/terapia , Dissulfetos , Proteína p300 Associada a E1A , Eritropoetina/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia , Alcaloides Indólicos , Neoplasias Hepáticas/patologia , Luciferases/metabolismo , Masculino , Camundongos , Camundongos Nus , Proteínas Nucleares/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Ligação Proteica/efeitos dos fármacos , Receptores de Hidrocarboneto Arílico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Transativadores/genética , Fatores de Transcrição/genética , Transplante Heterólogo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
A series of N-hydroxy-3-phenyl-2-propenamides were prepared as novel inhibitors of human histone deacetylase (HDAC). These compounds were potent enzyme inhibitors, having IC(50)s < 400 nM in a partially purified enzyme assay. However, potency in cell growth inhibition assays ranged over 2 orders of magnitude in two human carcinoma cell lines. Selected compounds having cellular IC(50) < 750 nM were tested for maximum tolerated dose (MTD) and for efficacy in the HCT116 human colon tumor xenograft assay. Four compounds having an MTD > or = 100 mg/kg were selected for dose-response studies in the HCT116 xenograft model. One compound, 9 (NVP-LAQ824), had significant dose-related activity in the HCT116 colon and A549 lung tumor models, high MTD, and low gross toxicity. On the basis, in part, of these properties, 9 has entered human clinical trials in 2002.
Assuntos
Acetiltransferases/antagonistas & inibidores , Acrilamidas/síntese química , Acrilamidas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Ácidos Hidroxâmicos/síntese química , Ácidos Hidroxâmicos/farmacologia , Proteínas de Saccharomyces cerevisiae/antagonistas & inibidores , Animais , Peso Corporal/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Histona Acetiltransferases , Humanos , Indicadores e Reagentes , Camundongos , Camundongos Nus , Conformação Molecular , Transplante de NeoplasiasRESUMO
LAF389 is a synthetic analogue of bengamides, a class of marine natural products that produce inhibitory effects on tumor growth in vitro and in vivo. A proteomics-based approach has been used to identify signaling pathways affected by bengamides. LAF389 treatment of cells resulted in altered mobility of a subset of proteins on two-dimensional gel electrophoresis. Detailed analysis of one of the proteins, 14-3-3gamma, showed that bengamide treatment resulted in retention of the amino-terminal methionine, suggesting that bengamides directly or indirectly inhibited methionine aminopeptidases (MetAps). Both known MetAps are inhibited by LAF389. Short interfering RNA suppression of MetAp2 also altered amino-terminal processing of 14-3-3gamma. A high resolution structure of human MetAp2 co-crystallized with a bengamide shows that the compound binds in a manner that mimics peptide substrates. Additionally, the structure reveals that three key hydroxyl groups on the inhibitor coordinate the di-cobalt center in the enzyme active site.
Assuntos
Aminopeptidases/química , Azepinas/farmacologia , Proteínas 14-3-3 , Aminopeptidases/antagonistas & inibidores , Aminopeptidases/genética , Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Sítios de Ligação , Divisão Celular , Linhagem Celular Tumoral , Clonagem Molecular , Cobalto/química , Cristalografia por Raios X , Cicloexanos , Relação Dose-Resposta a Droga , Eletroforese em Gel Bidimensional , Inibidores Enzimáticos/farmacologia , Ácidos Graxos Insaturados/farmacologia , Glicoproteínas/química , Glicoproteínas/genética , Humanos , Metionil Aminopeptidases , Modelos Químicos , Modelos Moleculares , Peptídeos/química , Ligação Proteica , Isoformas de Proteínas , Estrutura Terciária de Proteína , Proteoma , RNA Interferente Pequeno/metabolismo , Sesquiterpenos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Tirosina 3-Mono-Oxigenase/metabolismoRESUMO
Four novel bisulfide bromotyrosine derivatives, psammaplins E (9), F (10), G (11), and H (12), and two new bromotyrosine derivatives, psammaplins I (13) and J (14), were isolated from the sponge Pseudoceratina purpurea, along with known psammaplins A (4), B (6), C (7), and D (8) and bisaprasin (5). The structures of psammaplins E (9) and F (10), which each contain an oxalyl group rarely found in marine organisms, were determined by spectroscopic analysis. Compounds 4, 5, and 10 are potent histone deacetylase inhibitors and also show mild cytotoxicity. Furthermore, compounds 4, 5, and 11 are potent DNA methyltransferase inhibitors. The biogenetic pathway previously proposed for the psammaplins class is also revisited.
Assuntos
Metilases de Modificação do DNA/antagonistas & inibidores , Dissulfetos/isolamento & purificação , Inibidores Enzimáticos/isolamento & purificação , Inibidores de Histona Desacetilases , Poríferos/química , Ésteres do Ácido Sulfúrico/isolamento & purificação , Tirosina/análogos & derivados , Tirosina/isolamento & purificação , Animais , Dissulfetos/química , Dissulfetos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Papua Nova Guiné , Ésteres do Ácido Sulfúrico/química , Ésteres do Ácido Sulfúrico/farmacologia , Tirosina/química , Tirosina/farmacologiaRESUMO
A series of saturated heterocyclic analogues of distamycin were prepared and examined. A fluorescent intercalator displacement (FID) assay conducted on p[dA]-p[dT] DNA to obtain C(50) values and a hairpin deoxyoligonucleotide containing an A/T-rich binding site was used to evaluate DNA binding affinity. It is observed that saturated heterocycles greatly reduce the DNA binding relative to distamycin.
Assuntos
DNA/metabolismo , Distamicinas/metabolismo , Distamicinas/síntese química , Distamicinas/químicaRESUMO
A series of alpha-substituted beta-alanine (beta) linked polyamides (DbaPyPyPy-beta*-PyPyPy) were prepared and examined. This resulted in the observation that while most substituents disrupt DNA binding, (R)-alpha-methoxy-beta-alanine (beta((R)-OMe)) maintains strong binding affinity and preferentially adopts a hairpin versus extended binding mode, providing an alternative hairpin linker to gamma-aminobutyric acid (gamma). A generalized variant of a fluorescent intercalator displacement assay conducted on a series of hairpin deoxyoligonucleotides containing a systematically varied A/T-rich binding site size was developed to distinguish between the extended binding of the parent beta-alanine 1 (DbaPyPyPy-beta-PyPyPy) and the hairpin binding of 3 (DbaPyPyPy-beta((R)-OMe)-PyPyPy).
Assuntos
Alanina/química , DNA/química , Nylons/química , Reagentes de Ligações Cruzadas/química , DNA/metabolismo , Substâncias Intercalantes/química , Modelos Moleculares , Conformação de Ácido Nucleico , Nylons/síntese química , Nylons/metabolismo , Pirróis/síntese química , Pirróis/química , Pirróis/metabolismoRESUMO
Inhibitors of histone deacetylase (HDAC) have been shown to induce terminal differentiation of human tumor cell lines and to have antitumor effects in vivo. We have prepared analogues of suberoylanilide hydroxamic acid (SAHA) and trichostatin A and have evaluated them in a human HDAC enzyme inhibition assay, a p21(waf1) (p21) promoter assay, and in monolayer growth inhibition assays. One compound, 4-(dimethylamino)-N-[7-(hydroxyamino)-7-oxoheptyl]-benzamide, was found to affect the growth of a panel of eight human tumor cell lines differentially.