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OBJECTIVES: To understand the prevalence of psychosis in Aboriginal and Torres Strait Islander populations. METHODS: A systematic review of the literature was conducted using PubMed, Embase and Cochrane. RESULTS: Eight studies were reviewed. The prevalence of psychosis appeared higher in Aboriginal and Torres Strait Islanders, compared with non-Aboriginal and Torres Strait Islander populations. CONCLUSION: Although the literature suggests the prevalence of psychosis in Aboriginal and Torres Strait Islander populations is substantial, there are few studies and limited scope. Cultural competency is essential to understanding psychosis in this context.
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Aborigenas Australianos e Isleños del Estrecho de Torres , Servicios de Salud del Indígena , Trastornos Psicóticos , Humanos , Australia/epidemiología , Trastornos Psicóticos/epidemiologíaRESUMEN
Attempts to optimize pharmacokinetic properties in a promising series of pyrrolopyrimidinone MARK inhibitors for the treatment of Alzheimer's disease are described. A focus on physical properties and ligand efficiency while prosecuting this series afforded key tool compounds that revealed a large discrepancy in the rat in vitro-in vivo DMPK (Drug Metabolism/Pharmacokinetics) correlation. These differences prompted an in vivo rat disposition study employing a radiolabeled representative of the series, and the results from this experiment justified the termination of any further optimization efforts.
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Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinonas/farmacología , Pirroles/farmacología , Enfermedad de Alzheimer/metabolismo , Animales , Relación Dosis-Respuesta a Droga , Humanos , Isoenzimas/antagonistas & inhibidores , Isoenzimas/metabolismo , Estructura Molecular , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/metabolismo , Pirimidinonas/química , Pirimidinonas/metabolismo , Pirroles/química , Pirroles/metabolismo , Ratas , Relación Estructura-ActividadRESUMEN
The initial structure activity relationships around an isoindoline uHTS hit will be described. Information gleaned from ligand co-crystal structures allowed for rapid refinements in both MARK potency and kinase selectivity. These efforts allowed for the identification of a compound with properties suitable for use as an in vitro tool compound for validation studies on MARK as a viable target for Alzheimer's disease.
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Diseño de Fármacos , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinonas/farmacología , Pirroles/farmacología , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Línea Celular , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Humanos , Modelos Moleculares , Estructura Molecular , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/metabolismo , Pirimidinonas/síntesis química , Pirimidinonas/química , Pirroles/síntesis química , Pirroles/química , Relación Estructura-ActividadRESUMEN
PURPOSE: The use of human acellular dermal matrices (ADM) has become routinely used in implant-based breast surgery. Notwithstanding the many benefits for tissue support, the morbidity associated with its use includes seroma and infection, among other potential complications. Some patients experience a specific complication called red breast syndrome (RBS), which has been linked to ADM use, but its exact etiology remains elusive. In our institution, AlloDerm aseptic regenerative tissue matrix was recently replaced with a ready-to-use sterile version that undergoes terminal sterilization, eliminating the need for rehydration. We want to determine if this change in processing affected complications, including RBS. METHODS: We conducted a retrospective chart review analyzing patients from January 1, 2011, to June 1, 2013, who underwent breast surgery with human ADM. Patients with aseptic AlloDerm were compared to patients with sterile AlloDerm. Data were analyzed using the Fisher exact test. RESULTS: A total of 167 reconstructed breasts from 105 patients met inclusion criteria: 56% (n=93) with aseptic ADM, 44% (n=74) with sterile ADM. When comparing the two, patients had a decrease in overall necrosis, infection, seroma, and RBS with sterile ADM. However, the rates did not reach statistical significance. For example, the incidence of RBS decreased from 7.5% to 2.7% (P=0.301) and seroma decreased from 8.6% to 2.7% (P=0.188). The infection rate proved to be equivocal at 11.8% with aseptic ADM to 10.8% with sterile ADM (P=1.000). The only statistically significant change was a decrease in the total complication rate from 41.9% to 27.0% (P=0.046). The absolute risk reduction for total complications was 14.9% with a number-needed-to-treat of 7. CONCLUSION: According to our study, sterile AlloDerm has a clinically decreased incidence of complications compared to aseptic AlloDerm. Whereas RBS decreased, it was interesting to see that it was not eliminated altogether. This suggests that the etiology may be unrelated to ADM processing and warrants further investigation. Overall, the most notable difference was the statistically significant decrease in the total complication rate. Therefore, the change to sterile AlloDerm seems to be beneficial. Further benefit arises from ease of preparation in the operating room.
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Dermis Acelular , Infecciones Bacterianas/etiología , Infecciones Bacterianas/prevención & control , Enfermedades de la Mama/etiología , Enfermedades de la Mama/prevención & control , Mamoplastia/métodos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Índice de Masa Corporal , Colágeno , Femenino , Humanos , Infertilidad , Persona de Mediana Edad , Estudios Retrospectivos , SíndromeRESUMEN
BACKGROUND: Little evidence within plastic surgery literature supports the precept that longer operative times lead to greater morbidity. OBJECTIVE: The authors investigate surgery duration as a determinant of morbidity, with the goal of defining a clinically relevant time for increased risk. METHODS: A retrospective chart review was conducted of patients who underwent a broad range of complex plastic surgical procedures (n = 1801 procedures) at UT Southwestern Medical Center in Dallas, Texas, from January 1, 2008 to January 31, 2012. Adjusting for possible confounders, multivariate logistic regression assessed surgery duration as an independent predictor of morbidity. To define a cutoff for increased risk, incidence of complications was compared among quintiles of surgery duration. Stratification by type of surgery controlled for procedural complexity. RESULTS: A total of 1753 cases were included in multivariate analyses with an overall complication rate of 27.8%. Most operations were combined (75.8%), averaging 4.9 concurrent procedures. Each hour increase in surgery duration was associated with a 21% rise in odds of morbidity (P < .0001). Compared with the first quintile of operative time (<2.0 hours), there was no change in complications until after 3.1 hours of surgery (odds ratio, 1.6; P = .017), with progressively greater odds increases of 3.1 times after 4.5 hours (P < .0001) and 4.7 times after 6.8 hours (P < .0001). When stratified by type of surgery, longer operations continued to be associated with greater morbidity. CONCLUSIONS: Surgery duration is an independent predictor of complications, with a significantly increased risk above 3 hours. Although procedural complexity undoubtedly affects morbidity, operative time should factor into surgical decision making.
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Técnicas Cosméticas/efectos adversos , Tempo Operativo , Procedimientos de Cirugía Plástica/efectos adversos , Complicaciones Posoperatorias/etiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Texas , Factores de Tiempo , Resultado del Tratamiento , Adulto JovenRESUMEN
OBJECTIVE: To determine the impact on insulin acquisition cost of a pharmacy program to convert insulin utilization from multidose vials to pen-delivery systems for long-term care residents covered by Medicare Part A, and managed care plans. DESIGN: Retrospective cost comparison. SETTING: Long-term care facilities. PATIENTS: Residents covered by Medicare Part A and managed care plans. INTERVENTIONS: Policy to replace insulin vials with pen devices, effective July 2009. MAIN OUTCOME MEASURES: Mean insulin cost-per-patient day (total insulin purchases divided by patient admission days) and pen utilization (pen purchases as a percent of total insulin purchases). RESULTS: Insulin purchase data covered 2,405 admissions in 75 facilities over the 12-month period ending June 2010. Pen device purchases increased from less than 1% to almost 35% of total insulin purchases over the study period during which insulin cost per patient-day declined from $10.29 to $4.08. For Medicare Part A patients with admissions of 30 days or fewer, the most frequent visit type, mean cost per patient-day decreased from $13.73 to $9.19 as pen purchases increased from less than 1% to about 32%. For these same patients, mean cost per patient-day for admissions using only pen devices was $7.04, compared with $11.79 for admissions using only vials (P < 0.001). Significant differences in mean cost per patient-day were also found for residents covered by managed care and for longer admissions. CONCLUSION: Total insulin costs can be reduced through higher utilization of pen devices by patients in long-term care facilities.
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Sistemas de Liberación de Medicamentos/economía , Instituciones de Salud/economía , Insulina/administración & dosificación , Insulina/economía , Cuidados a Largo Plazo/economía , Consultores , Costos de la Atención en Salud , Humanos , Programas Controlados de Atención en Salud/economía , Medicare Part A/economía , Farmacia , Estudios Retrospectivos , Estados UnidosRESUMEN
The design, synthesis, and binding activity of ring constrained analogs of the acyclic cannabinoid-1 receptor (CB1R) inverse agonist taranabant 1 are described. The initial inspiration for these taranabant derivatives was its conformation 1a, determined by (1)H NMR, X-ray, and molecular modeling. The constrained analogs were all much less potent than their acyclic parent structure. The results obtained are discussed in the context of a predicted binding of 1 to a homology model of CB1R.
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Amidas/química , Fármacos Antiobesidad/síntesis química , Piridinas/química , Receptor Cannabinoide CB1/química , Amidas/síntesis química , Amidas/farmacología , Fármacos Antiobesidad/química , Fármacos Antiobesidad/farmacología , Simulación por Computador , Humanos , Modelos Moleculares , Conformación Molecular , Unión Proteica , Piridinas/síntesis química , Piridinas/farmacología , Receptor Cannabinoide CB1/metabolismoRESUMEN
BACKGROUND: Although there have been reports of single-surgeon outcomes with highly cohesive, form-stable silicone gel implants in women undergoing primary breast augmentation, there has been only one study published that compares the outcomes between the Allergan 410 and the Mentor CPG devices. OBJECTIVES: The goal of the study is to compare outcomes in each cohort and to determine if quality systems and processes would have an impact on lowering the surgical revision rate, as compared to published reports for round gel implants and form-stable implants. METHODS: Patients selected for the study were required to meet predefined inclusion criteria and general indications for breast augmentation. All subjects were treated uniformly with extensive informed consent prior to surgery. The entire process of breast augmentation (patient assessment, informed consent, the surgical procedure itself and postoperative instructions) was identical between the two groups. Patients were not randomized, as the studies did not start at the same time. The process for management of each patient was based on adaptation of the Toyota Production System and Lean Manufacturing, with emphasis on achieving operational excellence in the use of planning templates for surgery, including accurate management of patient expectations regarding size outcome. RESULTS: Outcomes data included physical breast measurements, quality of life metrics, and patient/surgeon satisfaction assessment. Adverse events were compared against published data for breast implants. Follow-up ranged between 20-77 months (Allergan 410) and 16-77 months (Mentor CPG). The outcome data indicate that these devices produce natural-appearing breasts with extremely low aggregate reoperation rate (4.2%). Only 0.8% of the reoperations were attributable to surgeon-related factors. There were no reoperations to correct mismanaged size expectations during the course of each study. There were 13 pregnancies and no difficulties with lactation were reported. Rippling (lateral/medial, palpable and/or visible) was encountered in both cohorts. The Mentor CPG cohort had a fivefold greater incidence of rippling (37.3% versus 7.6% in Allergan 410 cohort). This was highly statistically significant (P < .001). CONCLUSIONS: Provided that there is adherence to core principles and avoidance of errors in planning, patient expectations, and surgery, highly cohesive, form-stable breast implants can deliver excellent long term outcomes in primary breast augmentation in a diverse patient population. The impact of quality processes such as Toyota Production System and Lean Manufacturing was substantive in delivering operational excellence in primary breast augmentation.
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Implantación de Mama/métodos , Implantes de Mama/estadística & datos numéricos , Adolescente , Adulto , Implantación de Mama/estadística & datos numéricos , Estudios de Cohortes , Diseño de Equipo , Femenino , Estudios de Seguimiento , Humanos , Satisfacción del Paciente/estadística & datos numéricos , Calidad de Vida , Reoperación , Resultado del Tratamiento , Adulto JovenRESUMEN
Pharmacological activation of the STING (stimulator of interferon genes)-controlled innate immune pathway is a promising therapeutic strategy for cancer. Here we report the identification of MSA-2, an orally available non-nucleotide human STING agonist. In syngeneic mouse tumor models, subcutaneous and oral MSA-2 regimens were well tolerated and stimulated interferon-ß secretion in tumors, induced tumor regression with durable antitumor immunity, and synergized with anti-PD-1 therapy. Experimental and theoretical analyses showed that MSA-2 exists as interconverting monomers and dimers in solution, but only dimers bind and activate STING. This model was validated by using synthetic covalent MSA-2 dimers, which were potent agonists. Cellular potency of MSA-2 increased upon extracellular acidification, which mimics the tumor microenvironment. These properties appear to underpin the favorable activity and tolerability profiles of effective systemic administration of MSA-2.
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Antineoplásicos/farmacología , Proteínas de la Membrana/metabolismo , Administración Oral , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacocinética , HumanosRESUMEN
Obesity is a chronic medical condition that is affecting large population throughout the world. CB1 as a target for treatment of obesity has been under intensive studies. Taranabant was discovered and then developed by Merck as the 1st generation CB1R inverse agonist. Reported here is part of our effort on the 2nd generation of CB1R inverse agonist from the acyclic amide scaffold. We replaced the oxygen linker in taranabant with nitrogen and prepared a series of amino heterocyclic analogs through a divergent synthesis. Although in general, the amine linker gave reduced binding affinity, potent and selective CB1R inverse agonist was identified from the amino heterocycle series. Molecular modeling was applied to study the binding of the amino heterocycle series at CB1 binding site. The in vitro metabolism of representative members was studied and only trace glucuronidation was found. Thus, it suggests that the right hand side of the molecule may not be the appropriate site for glucuronidation.
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Amidas/química , Fármacos Antiobesidad/química , Piridinas/química , Receptor Cannabinoide CB1/antagonistas & inhibidores , Amidas/síntesis química , Amidas/farmacología , Animales , Fármacos Antiobesidad/síntesis química , Fármacos Antiobesidad/farmacología , Sitios de Unión , Simulación por Computador , Agonismo Inverso de Drogas , Humanos , Microsomas Hepáticos/metabolismo , Piridinas/farmacología , Ratas , Receptor Cannabinoide CB1/metabolismo , Receptor Cannabinoide CB2/agonistas , Receptor Cannabinoide CB2/metabolismo , Proteínas Recombinantes/agonistas , Proteínas Recombinantes/metabolismoRESUMEN
Drugging large protein pockets is a challenge due to the need for higher molecular weight ligands, which generally possess undesirable physicochemical properties. In this communication, we highlight a strategy leveraging small molecule active site dimers to inhibit the large symmetric binding pocket in the STING protein. By taking advantage of the 2:1 binding stoichiometry, maximal buried interaction with STING protein can be achieved while maintaining the ligand physicochemical properties necessary for oral exposure. This mode of binding requires unique considerations for potency optimization including simultaneous optimization of protein-ligand as well as ligand-ligand interactions. Successful implementation of this strategy led to the identification of 18, which exhibits good oral exposure, slow binding kinetics, and functional inhibition of STING-mediated cytokine release.
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The discovery of a structurally distinct cannabinoid-1 receptor (CB1R) positron emission tomography tracer is described. Starting from an acyclic amide CB1R inverse agonist (1) as the lead compound, an efficient route to introduce 18F to the molecule was developed. Further optimization focused on reducing the lipophilicity and increasing the CB1R affinity. These efforts led to the identification of [18F]-16 that exhibited good brain uptake and an excellent signal-to-noise ratio in rhesus monkeys.
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Amidas/síntesis química , Radioisótopos de Flúor , Piridinas/síntesis química , Radiofármacos/síntesis química , Receptor Cannabinoide CB1/metabolismo , Amidas/química , Amidas/farmacocinética , Animales , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Células CHO , Cricetinae , Cricetulus , Humanos , Macaca mulatta , Tomografía de Emisión de Positrones , Piridinas/química , Piridinas/farmacocinética , Ensayo de Unión Radioligante , Radiofármacos/química , Radiofármacos/farmacocinética , Receptor Cannabinoide CB1/agonistas , Receptor Cannabinoide CB1/antagonistas & inhibidores , Proteínas Recombinantes/metabolismo , Relación Estructura-ActividadRESUMEN
The discovery of novel acyclic amide cannabinoid-1 receptor inverse agonists is described. They are potent, selective, orally bioavailable, and active in rodent models of food intake and body weight reduction. A major focus of the optimization process was to increase in vivo efficacy and to reduce the potential for formation of reactive metabolites. These efforts led to the identification of compound 48 for development as a clinical candidate for the treatment of obesity.
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Fármacos Antiobesidad/farmacología , Cannabinoides/farmacología , Obesidad/tratamiento farmacológico , Receptor Cannabinoide CB1/agonistas , Receptor Cannabinoide CB2/agonistas , Animales , Fármacos Antiobesidad/síntesis química , Fármacos Antiobesidad/química , Peso Corporal/efectos de los fármacos , Cannabinoides/síntesis química , Cannabinoides/química , AMP Cíclico/metabolismo , Ingestión de Alimentos/efectos de los fármacos , Humanos , Hígado/efectos de los fármacos , Hígado/metabolismo , Microsomas/efectos de los fármacos , Microsomas/metabolismo , Ratas , Receptor Cannabinoide CB1/antagonistas & inhibidores , Receptor Cannabinoide CB1/metabolismo , Receptor Cannabinoide CB2/antagonistas & inhibidores , Receptor Cannabinoide CB2/metabolismoRESUMEN
Development of a series of highly kinome-selective spleen tyrosine kinase (Syk) inhibitors with favorable druglike properties is described. Early leads were discovered through X-ray crystallographic analysis, and a systematic survey of cores within a selected chemical space focused on ligand binding efficiency. Attenuation of hERG ion channel activity inherent within the initial chemotype was guided through modulation of physicochemical properties including log D, PSA, and pKa. PSA proved most effective for prospective compound design. Further profiling of an advanced compound revealed bacterial mutagenicity in the Ames test using TA97a Salmonella strain, and subsequent study demonstrated that this mutagenicity was pervasive throughout the series. Identification of intercalation as a likely mechanism for the mutagenicity-enabled modification of the core scaffold. Implementation of a DNA binding assay as a prescreen and models in DNA allowed resolution of the mutagenicity risk, affording molecules with favorable potency, selectivity, pharmacokinetic, and off-target profiles.
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Amidas/farmacología , Canales de Potasio Éter-A-Go-Go/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Bazo/enzimología , Amidas/síntesis química , Amidas/química , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Canales de Potasio Éter-A-Go-Go/genética , Canales de Potasio Éter-A-Go-Go/metabolismo , Humanos , Modelos Moleculares , Estructura Molecular , Pruebas de Mutagenicidad , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Proteínas Tirosina Quinasas/metabolismo , Bazo/efectos de los fármacos , Relación Estructura-ActividadRESUMEN
Metabolic activation of drug candidates to electrophilic reactive metabolites that can covalently modify cellular macromolecules may result in acute and/or idiosyncratic immune system-mediated toxicities in humans. This presents a significant potential liability for the future development of these compounds as safe therapeutic agents. We present here an example of an approach where sites of metabolic activation within a new drug candidate series were rapidly identified using online liquid chromatography/multi-stage mass spectrometry on an ion trap mass spectrometer. This was accomplished by trapping the reactive intermediates formed upon incubation of compounds with rat and human liver microsomes as their corresponding glutathione conjugates and mass spectral characterization of these thiol adducts. Based on the structures of the GSH adducts identified, potential sites and mechanisms of bioactivation within the chemical structure were proposed. These metabolism studies were interfaced with iterative structural modifications of the chemical series in order to block these bioactivation sites within the molecule. This strategy led to a significant reduction in the propensity of the compounds to undergo metabolic activation as evidenced by reductions in the irreversible binding of radioactivity to liver microsomal material upon incubation of tritium-labeled compounds with this in vitro system. With the efficiency and throughput achievable with such an approach, it appears feasible to identify and address the metabolic activation potential of new drug leads during routine metabolite identification studies in an early drug discovery setting.
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Drogas en Investigación/farmacocinética , Espectrometría de Masa por Ionización de Electrospray , Animales , Biotransformación , Drogas en Investigación/análisis , Glutatión/metabolismo , Humanos , Masculino , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad , TritioRESUMEN
We report the development and characterization of compound 22 (MK-5046), a potent, selective small molecule agonist of BRS-3 (bombesin receptor subtype-3). In pharmacological testing using diet-induced obese mice, compound 22 caused mechanism-based, dose-dependent reductions in food intake and body weight.
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c-Met is a transmembrane tyrosine kinase that mediates activation of several signaling pathways implicated in aggressive cancer phenotypes. In recent years, research into this area has highlighted c-Met as an attractive cancer drug target, triggering a number of approaches to disrupt aberrant c-Met signaling. Screening efforts identified a unique class of 5H-benzo[4,5]cyclohepta[1,2-b]pyridin-5-one kinase inhibitors, exemplified by 1. Subsequent SAR studies led to the development of 81 (MK-2461), a potent inhibitor of c-Met that was efficacious in preclinical animal models of tumor suppression. In addition, biochemical studies and X-ray analysis have revealed that this unique class of kinase inhibitors binds preferentially to the activated (phosphorylated) form of the kinase. This report details the development of 81 and provides a description of its unique biochemical properties.
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Antineoplásicos/síntesis química , Benzocicloheptenos/síntesis química , Piridinas/síntesis química , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Animales , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Benzocicloheptenos/farmacocinética , Benzocicloheptenos/farmacología , Línea Celular Tumoral , Cristalografía por Rayos X , Perros , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Haplorrinos , Humanos , Ratones , Ratones Desnudos , Modelos Moleculares , Mutación , Trasplante de Neoplasias , Fosforilación , Unión Proteica , Pirazoles/síntesis química , Pirazoles/farmacocinética , Pirazoles/farmacología , Piridinas/farmacocinética , Piridinas/farmacología , Ratas , Proteínas Tirosina Quinasas Receptoras/genética , Relación Estructura-Actividad , Sulfonamidas/síntesis química , Sulfonamidas/farmacocinética , Sulfonamidas/farmacología , Trasplante HeterólogoRESUMEN
The receptor tyrosine kinase c-Met is an attractive target for therapeutic blockade in cancer. Here, we describe MK-2461, a novel ATP-competitive multitargeted inhibitor of activated c-Met. MK-2461 inhibited in vitro phosphorylation of a peptide substrate recognized by wild-type or oncogenic c-Met kinases (N1100Y, Y1230C, Y1230H, Y1235D, and M1250T) with IC(50) values of 0.4 to 2.5 nmol/L. In contrast, MK-2461 was several hundredfold less potent as an inhibitor of c-Met autophosphorylation at the kinase activation loop. In tumor cells, MK-2461 effectively suppressed constitutive or ligand-induced phosphorylation of the juxtamembrane domain and COOH-terminal docking site of c-Met, and its downstream signaling to the phosphoinositide 3-kinase-AKT and Ras-extracellular signal-regulated kinase pathways, without inhibiting autophosphorylation of the c-Met activation loop. BIAcore studies indicated 6-fold tighter binding to c-Met when it was phosphorylated, suggesting that MK-2461 binds preferentially to activated c-Met. MK-2461 displayed significant inhibitory activities against fibroblast growth factor receptor (FGFR), platelet-derived growth factor receptor, and other receptor tyrosine kinases. In cell culture, MK-2461 inhibited hepatocyte growth factor/c-Met-dependent mitogenesis, migration, cell scatter, and tubulogenesis. Seven of 10 MK-2461-sensitive tumor cell lines identified from a large panel harbored genomic amplification of MET or FGFR2. In a murine xenograft model of c-Met-dependent gastric cancer, a well-tolerated oral regimen of MK-2461 administered at 100 mg/kg twice daily effectively suppressed c-Met signaling and tumor growth. Similarly, MK-2461 inhibited the growth of tumors formed by s.c. injection of mouse NIH-3T3 cells expressing oncogenic c-Met mutants. Taken together, our findings support further preclinical development of MK-2461 for cancer therapy.
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Antineoplásicos/farmacología , Sistemas de Liberación de Medicamentos , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Células Cultivadas , Perros , Sistemas de Liberación de Medicamentos/métodos , Activación Enzimática/efectos de los fármacos , Femenino , Haplorrinos , Humanos , Ratones , Ratones Desnudos , Células 3T3 NIH , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas c-met/metabolismo , Especificidad por Sustrato/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
PURPOSE: The in vitro and in vivo evaluation of the selective, high affinity (human CB1 IC(50) 0.49 nM) inverse agonist CB1R tracer [(11)C]CB-119, a close analog of the previously disclosed [(18)F]MK-9470, was undertaken. PROCEDURES: [(11)C]CB-119 was synthesized with high specific activity by alkylation of a phenolic precursor with [(11)C]methyl iodide. In vitro autoradiographic studies using rhesus brain slices were carried out using [(3)H]CB-119, and in vivo imaging studies were carried out using [(11)C]CB-119 in rhesus monkeys under baseline and blocked conditions. RESULTS: Autoradiographic studies in rhesus brain showed the expected distribution pattern for CB1R with highest binding in the cerebral cortex, cerebellum, caudate/putamen, globus pallidus, substantia nigra, and hippocampus. Lower binding was seen in the posterior hypothalamus, ventral tegmental area, and periventricular gray area, and the lowest binding was in the thalamic nuclei. The binding of [(3)H]CB-119 was fully blocked by the addition of 10 microM CB-119. Rhesus positron emission tomography imaging studies showed very good brain uptake and a distribution pattern consistent with that seen in the autoradiographic studies. The kinetics of tracer uptake was slow. The brain uptake was blocked by pretreatment with taranabant, a CB1R inverse agonist. The specific signal (total/nonspecific) in rhesus putamen at 90 min was approximately 6:1. CONCLUSIONS: [(11)C]CB-119 is a suitable tracer for imaging central CB1 receptors.
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Amidas/metabolismo , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Tomografía de Emisión de Positrones , Piridinas/metabolismo , Radiofármacos/metabolismo , Receptor Cannabinoide CB1/metabolismo , Animales , Autorradiografía , Radioisótopos de Carbono , Ligandos , Macaca mulatta , Unión Proteica , Receptor Cannabinoide CB1/agonistas , Distribución Tisular , Tritio/químicaRESUMEN
Extremely potent very late antigen-4 (VLA-4) antagonists with picomolar, whole blood activity and slow dissociation rates were discovered by incorporating an amino substituent on the proline fragment of the initial lead structure. This level of potency against the unactivated form of VLA-4 was shown to be sufficient to overcome the poor pharmacokinetic profiles typical of this class of VLA-4 antagonists, and sustained activity as measured by receptor occupancy was achieved in preclinical species after oral dosing.