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1.
Clin Cancer Res ; 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39167622

RESUMEN

BACKGROUND: AZD5991, a human MCL-1 inhibitor, was assessed for safety, tolerability, pharmacokinetics (PK), and antitumor activity as monotherapy and in combination with venetoclax in patients with relapsed or refractory (R/R) hematologic malignancies. METHODS: In the monotherapy cohort (n=61), patients with hematologic malignancies received AZD5991 intravenously in escalating doses either once or twice weekly, following intrapatient dose escalation, on a 3-week cycle. In the combination cohort (n=17), patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) received escalating doses of AZD5991 and venetoclax on either a 3-week or 4-week cycle. Primary objectives were safety and maximum tolerated dose; secondary objectives included plasma PK and antitumor activity. RESULTS: The most common (≥30%) adverse events (AEs) were diarrhea (59.0%), nausea (55.1%), and vomiting (47.4%). Four deaths occurred due to AEs: cardiac arrest, sepsis, tumor lysis syndrome (TLS), and acute respiratory failure; only TLS was related to AZD5991. Dose-limiting toxicities occurred in 5 patients. Three patients with MDS achieved an objective response: 1 marrow complete remission (mCR) without hematologic improvement, 1 partial remission with AZD5991 monotherapy, and 1 mCR with AZD5991+venetoclax. Asymptomatic elevations of troponin I or T were observed in 8 (10.3%) patients. Post hoc retrospective analysis revealed elevated troponin T in 14/31 patients before any AZD5991 dose and in 54/65 patients after any AZD5991 dose at or after cycle 1. There were no associations between elevated troponin and cardiovascular risk factors. CONCLUSIONS: Treatment with AZD5991 was associated with high incidence of laboratory troponin elevation and a low overall response rate.

2.
Cancer Chemother Pharmacol ; 88(6): 941-952, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34477937

RESUMEN

INTRODUCTION: Fedratinib, an oral, selective Janus kinase 2 inhibitor, has been shown to inhibit P-glycoprotein (P-gp), breast cancer resistance protein (BCRP), organic anion transporting polypeptide (OATP) 1B1, OATP1B3, organic cation transporter (OCT) 2, and multidrug and toxin extrusion (MATE) 1 and MATE2-K in vitro. The objective of this study was to evaluate the influence of fedratinib on the pharmacokinetics (PK) of digoxin (P-gp substrate), rosuvastatin (OATP1B1/1B3 and BCRP substrate), and metformin (OCT2 and MATE1/2-K substrate). METHODS: In this nonrandomized, fixed-sequence, open-label study, 24 healthy adult participants received single oral doses of digoxin 0.25 mg, rosuvastatin 10 mg, and metformin 1000 mg administered as a drug cocktail (day 1, period 1). After a 6-day washout, participants received oral fedratinib 600 mg 1 h before the cocktail on day 7 (period 2). An oral glucose tolerance test (OGTT) was performed to determine possible influences of fedratinib on the antihyperglycemic effect of metformin. RESULTS: Plasma exposure to the three probe drugs was generally comparable in the presence or absence of fedratinib. Reduced metformin renal clearance by 36% and slightly higher plasma glucose levels after OGTT were observed in the presence of fedratinib. Single oral doses of the cocktail ± fedratinib were generally well tolerated. CONCLUSIONS: These results suggest that fedratinib has minimal impact on the exposure of P-gp, BCRP, OATP1B1/1B3, OCT2, and MATE1/2-K substrates. Since renal clearance of metformin was decreased in the presence of fedratinib, caution should be exercised in using coadministered drugs that are renally excreted via OCT2 and MATEs. TRIAL REGISTRATION: Clinicaltrials.gov NCT04231435 on January 18, 2020.


Asunto(s)
Digoxina/farmacocinética , Interacciones Farmacológicas , Metformina/farmacocinética , Pirrolidinas/farmacología , Rosuvastatina Cálcica/farmacocinética , Sulfonamidas/farmacología , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/antagonistas & inhibidores , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/antagonistas & inhibidores , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/metabolismo , Administración Oral , Adolescente , Adulto , Anciano , Anticolesterolemiantes/farmacocinética , Transporte Biológico , Cardiotónicos/farmacocinética , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Voluntarios Sanos , Humanos , Hipoglucemiantes/farmacocinética , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/metabolismo , Ensayos Clínicos Controlados no Aleatorios como Asunto , Transportadores de Anión Orgánico/antagonistas & inhibidores , Transportadores de Anión Orgánico/metabolismo , Distribución Tisular , Adulto Joven
3.
Microorganisms ; 9(7)2021 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-34361923

RESUMEN

Antibiotic biosynthesis by microorganisms is commonly regulated through autoinduction, which allows producers to quickly amplify the production of antibiotics in response to environmental cues. Antibiotic autoinduction generally involves one pathway-specific transcriptional regulator that perceives an antibiotic as a signal and then directly stimulates transcription of the antibiotic biosynthesis genes. Pyoluteorin is an autoregulated antibiotic produced by some Pseudomonas spp. including the soil bacterium Pseudomonas protegens Pf-5. In this study, we show that PltR, a known pathway-specific transcriptional activator of pyoluteorin biosynthesis genes, is necessary but not sufficient for pyoluteorin autoinduction in Pf-5. We found that pyoluteorin is perceived as an inducer by PltZ, a second pathway-specific transcriptional regulator that directly represses the expression of genes encoding a transporter in the pyoluteorin gene cluster. Mutation of pltZ abolished the autoinducing effect of pyoluteorin on the transcription of pyoluteorin biosynthesis genes. Overall, our results support an alternative mechanism of antibiotic autoinduction by which the two pathway-specific transcriptional regulators PltR and PltZ coordinate the autoinduction of pyoluteorin in Pf-5. Possible mechanisms by which PltR and PltZ mediate the autoinduction of pyoluteorin are discussed.

4.
Cancer Chemother Pharmacol ; 88(3): 369-377, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34019108

RESUMEN

PURPOSE: Fedratinib is an oral and selective Janus kinase 2 inhibitor that is indicated for treatment of adults with intermediate-2 or high-risk primary or secondary myelofibrosis. Fedratinib is metabolized by cytochrome P450s (CYPs), primarily CYP3A4. The objective of this study was to determine the effects of the strong CYP3A4 inducer rifampin and moderate CYP3A4 inducer efavirenz on the pharmacokinetics of single doses of fedratinib. METHODS: This Phase 1, open-label, two-part study (Part 1 for rifampin and Part 2 for efavirenz) was conducted in healthy adult men and women. A single dose of fedratinib (500 mg) was administered on Day 1. Participants received rifampin 600 mg daily or efavirenz 600 mg daily on Days 9-18. On Day 17, a single dose of fedratinib (500 mg) was coadministered with rifampin or efavirenz. Plasma fedratinib concentrations were measured using validated liquid chromatography-tandem mass spectrometry. RESULTS: Maximum observed plasma fedratinib concentrations were lowered by approximately 70% and 30% during coadministration with rifampin or efavirenz, respectively, compared with fedratinib alone. Geometric means of fedratinib area under the plasma concentration-time curve from 0 to infinity were decreased by 81% (90% confidence interval [CI], 77-83%) and 47% (90% CI, 40-53%) during coadministration with rifampin or efavirenz, respectively. Fedratinib was generally well tolerated when administered alone or in combination with rifampin or efavirenz. CONCLUSION: Significant reductions in fedratinib exposure were observed in the presence of strong or moderate CYP3A4 inducers. These results suggest that agents that are strong or moderate inducers of CYP3A4 should be avoided when coadministered with fedratinib. TRIAL REGISTRATION NUMBER: NCT03983239 (Registration date: June 12, 2019).


Asunto(s)
Inductores del Citocromo P-450 CYP3A/farmacología , Inhibidores de Proteínas Quinasas/farmacocinética , Pirrolidinas/farmacocinética , Sulfonamidas/farmacocinética , Adulto , Alquinos/farmacología , Área Bajo la Curva , Benzoxazinas/farmacología , Cromatografía Liquida , Ciclopropanos/farmacología , Interacciones Farmacológicas , Femenino , Humanos , Janus Quinasa 2/antagonistas & inhibidores , Masculino , Persona de Mediana Edad , Inhibidores de Proteínas Quinasas/efectos adversos , Pirrolidinas/efectos adversos , Rifampin/farmacología , Sulfonamidas/efectos adversos , Espectrometría de Masas en Tándem , Adulto Joven
5.
J Clin Neurosci ; 50: 247-251, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29439906

RESUMEN

BACKGROUND: The management of dermoid cysts can be tedious as they have a tendency to recur, and respond poorly to chemotherapy and radiation. Management is especially difficult for tumors involving highly eloquent areas such as the conus medullaris. OBJECTIVE: We aim to provide a summary of the pathology, clinical presentation, and operative management strategies of dermoid cysts involving the conus medullaris. METHODS: Two clinical cases of dermoid cysts of the conus are presented, as well as a commented surgical video. RESULTS: A 33 year-old man with a history of cystic conus medullaris tumor presented with progressive low back pain and loss of bowel and bladder function. His magnetic resonance imaging (MRI) scan showed recurrence of his tumor with tethering of the spinal cord. He was taken for a midline myelotomy that drained yellowish keratinous fluid and decompressed the cyst. No aggressive attempt at complete resection of the cyst wall was undertaken. He made a complete recovery after surgery. A 25 year-old woman with a history of dermoid cyst of the conus that was previously treated surgically, presented with lower extremity weakness and debilitating pain. Her MRI showed significant recurrence of the cystic lesion. She was taken for a midline myelotomy and improved after surgery with complete resolution of her symptoms. CONCLUSION: Dermoid cysts of the conus medullaris are challenging to treat. Surgical control and restraint are key, especially when patients are young and could potentially fully recover and remain in remission for a period of years.


Asunto(s)
Quiste Dermoide/patología , Quiste Dermoide/cirugía , Neoplasias de la Médula Espinal/patología , Neoplasias de la Médula Espinal/cirugía , Adulto , Femenino , Humanos , Masculino , Procedimientos Neuroquirúrgicos/métodos
6.
J Pharm Pract ; 31(1): 107-111, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29278991

RESUMEN

OBJECTIVE: To report 2 cases of nonoperable intracranial bleeding associated with apixaban managed by 3-factor prothrombin complex concentrate (PCC3). CASE SUMMARIES: Case 1 presented with a 1.3-cm left parieto-occipital hemorrhage and a thin subdural hematoma (SDH) on the left tentorium of the brain about 6 hours after his last dose of apixaban. Case 2 presented with a 4-mm left parafalcine SDH with time of most recent apixaban dose unknown. The patients received 24.9 to 25.5 U/kg of PCC3 with none to 1 U fresh frozen plasma (FFP) and demonstrated minimal or no progression in lesions measured by repeat computed tomography (CT) after treatment. One patient was discharged to a skilled nursing facility after 8 days; the other patient was discharged to home after 18 days. DISCUSSION: Apixaban has no specific antidote. Current bleeding management strategies are based on expert opinion. The risks and benefits for differing strategies are unclear, and little clinical experience for managing apixaban-associated intracranial bleeding has been reported to date. These cases describe the clinical use of PCC3 to manage parieto-occipital and subdural hemorrhage associated with apixaban in events not requiring surgical intervention. CONCLUSION: In these 2 cases, 25 U/kg PCC3, with none to one unit FFP, ceased apixaban-associated intracranial bleeding without apparent thrombogenic complications.


Asunto(s)
Manejo de la Enfermedad , Inhibidores del Factor Xa/efectos adversos , Hemorragias Intracraneales/inducido químicamente , Hemorragias Intracraneales/terapia , Pirazoles/efectos adversos , Piridonas/efectos adversos , Anciano de 80 o más Años , Humanos , Hemorragias Intracraneales/diagnóstico por imagen , Masculino
7.
PLoS One ; 10(9): e0137585, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26356504

RESUMEN

To what extent can simple mental exercises cause shifts in empathic habits? Can we use mobile technology to make people more empathic? It may depend on how empathy is measured. Scholars have identified a number of different facets and correlates of empathy. This study is among the first to take a comprehensive, multidimensional approach to empathy to determine how empathy training could affect these different facets and correlates. In doing so, we can learn more about empathy and its multifaceted nature. Participants (N = 90) were randomly assigned to receive either an empathy-building text message program (Text to Connect) or one of two control conditions (active versus passive). Respondents completed measures of dispositional empathy (i.e. self-perceptions of being an empathic person), affective empathy (i.e. motivations to help, immediate feelings of empathic concern), and prosocial behavior (i.e. self-reports and observer-reports) at baseline, and then again after the 14 day intervention period. We found that empathy-building messages increased affective indicators of empathy and prosocial behaviors, but actually decreased self-perceptions of empathy, relative to control messages. Although the brief text messaging intervention did not consistently impact empathy-related personality traits, it holds promise for the use of mobile technology for changing empathic motivations and behaviors.


Asunto(s)
Empatía , Conducta Social , Envío de Mensajes de Texto , Femenino , Humanos , Masculino , Distribución Aleatoria
8.
Crit Care Med ; 43(9): 1952-63, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26154931

RESUMEN

OBJECTIVE: Recently, a concept of an individually targeted level of cerebral perfusion pressure that aims to restore impaired cerebral vasoreactivity has been advocated after traumatic brain injury. The relationship between cerebral perfusion pressure and pressure reactivity index normally is supposed to have a U-shape with its minimum interpreted as the value of "optimal" cerebral perfusion pressure. The aim of this study is to investigate the relation between the absence of the optimal cerebral perfusion pressure curve and physiological variables, clinical factors, and interventions. DESIGN: Retrospective analysis of prospectively collected data. SETTING: Neurocritical care units in two university centers. PATIENTS: Between May 2012 and December 2013, a total of 48 traumatic brain injury patients were studied with real-time annotation of predefined clinical events. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: All patients had continuous monitoring of arterial blood pressure, intracranial pressure, and cerebral perfusion pressure, with real-time calculations of pressure reactivity index and optimal cerebral perfusion pressure using ICM+ software (Cambridge Enterprise, University of Cambridge, Cambridge, UK). Selected clinical events were inserted on a daily basis, including changes in physiological variables, sedativeanalgesic drugs, vasoactive drugs, and medical/surgical therapies for intracranial hypertension. The collected data were divided into 4-hour periods, with the primary outcome being absence of the optimal cerebral perfusion pressure curve. For every period, mean values (± SDs) of arterial blood pressure, intracranial pressure, pressure reactivity index, and other physiological variables were calculated; clinical events were organized using predefined scales. In 28% of all 1,561 periods, an optimal cerebral perfusion pressure curve was absent. A generalized linear mixed model with binary logistic regression was fitted. Absence of slow arterial blood pressure waves (odds ratio, 2.7; p < 0.001), higher pressure reactivity index values (odds ratio, 2.9; p < 0.001), lower amount of sedative-analgesic drugs (odds ratio, 1.9; p = 0.03), higher vasoactive medication dose (odds ratio, 3.2; p = 0.02), no administration of maintenance neuromuscular blockers (odds ratio, 1.7; p < 0.01), and following decompressive craniectomy (odds ratio, 1.8; p < 0.01) were independently associated with optimal cerebral perfusion pressure curve absence. CONCLUSIONS: This study identified six factors that were independently associated with absence of optimal cerebral perfusion pressure curves.


Asunto(s)
Lesiones Encefálicas/fisiopatología , Circulación Cerebrovascular/fisiología , Presión Intracraneal/fisiología , Adulto , Analgésicos/administración & dosificación , Encéfalo/fisiopatología , Fármacos Cardiovasculares/administración & dosificación , Femenino , Escala de Coma de Glasgow , Humanos , Hipnóticos y Sedantes/administración & dosificación , Hipertensión Intracraneal/fisiopatología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
9.
Lancet Neurol ; 13(5): 461-71, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24680372

RESUMEN

BACKGROUND: Suvorexant (MK-4305) is an orexin receptor antagonist shown to be efficacious for insomnia over 3 months. We aimed to assess its clinical profile during and after 1 year of treatment. METHODS: We did a randomised, placebo-controlled, parallel-group trial at 106 investigational centres in the Americas, Australia, Europe, and South Africa from December, 2009, to August, 2011. Patients aged 18 years or older with primary insomnia by DSM-IV-TR criteria were assigned using a computer-generated randomised allocation schedule to receive nightly suvorexant (40 mg for patients younger than 65 years, 30 mg for patients aged 65 years or older) or placebo at a 2:1 ratio for 1 year with a subsequent 2-month randomised discontinuation phase in which patients on suvorexant either continued suvorexant or were abruptly switched to placebo while patients on placebo remained on placebo. Treatment assignment was masked from patients and investigators. The primary objective was to assess the safety and tolerability of suvorexant for up to 1 year. Secondary objectives were to assess the efficacy of suvorexant for improving patient-reported subjective total sleep time (sTST) and time to sleep onset (sTSO) over the first month of treatment. Efficacy endpoints over the first month were assessed with a mixed model with terms for baseline value of the response variable, age, sex, region, treatment, time, and treatment by time interaction. This trial is registered with ClinicalTrials.gov, number NCT01021813. FINDINGS: 322 (62%) of 522 patients randomly assigned to receive suvorexant and 162 (63%) of 259 assigned to receive placebo completed the 1-year phase. Over 1 year, 362 (69%) of 521 patients treated with suvorexant experienced any adverse events compared with 164 (64%) of 258 treated with placebo. Serious adverse events were recorded in 27 patients (5%) who received suvorexant and 17 (7%) who received placebo. The most common adverse event, somnolence, was reported for 69 patients (13%) who received suvorexant and seven (3%) who received placebo. At month 1, suvorexant (517 patients in the efficacy population) showed greater efficacy than placebo (254 in the efficacy population) in improving sTST (38·7 min vs 16·0 min; difference 22·7, 95% CI 16·4 to 29·0; p<0·0001) and sTSO (-18·0 min vs -8·4 min, difference -9·5, -14·6 to -4·5; p=0·0002). INTERPRETATION: Our findings show that suvorexant was generally safe and well tolerated over 1 year of nightly treatment in patients with insomnia, with efficacy noted for subjective measures of sleep onset and maintenance. FUNDING: Merck & Co Inc.


Asunto(s)
Azepinas/uso terapéutico , Hipnóticos y Sedantes/uso terapéutico , Antagonistas de los Receptores de Orexina , Trastornos del Inicio y del Mantenimiento del Sueño/tratamiento farmacológico , Triazoles/uso terapéutico , Adulto , Factores de Edad , Anciano , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Hipnóticos y Sedantes/farmacología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
10.
Acad Radiol ; 20(12): 1598-603, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24200488

RESUMEN

RATIONALE AND OBJECTIVES: To investigate the effect of being forewarned that they would be asked to identify repeated images on radiologists' recognition of previously interpreted versus new chest radiographs. MATERIALS AND METHODS: Thirteen radiologists viewed 60 posterior-anterior chest radiographs, 31 with and 29 without nodules, in two sets of 40 images each. Eight radiologists were forewarned and five radiologists were not forewarned of the memory task. Twenty images in each of the two sets were unique to each set and 20 images occurred in both sets. The readers indicated the presence or absence of any nodules during both readings, and in the second reading session they also indicated whether they thought each image had also occurred in the first reading. RESULTS: There was no significant difference in recognition memory performance between forewarned and not-forewarned readers. Overall accuracy in distinguishing previously-viewed from new images was 60.7%. CONCLUSIONS: Being forewarned of the memory task did not improve recognition memory.


Asunto(s)
Competencia Clínica/estadística & datos numéricos , Neoplasias Pulmonares/diagnóstico por imagen , Memoria/fisiología , Reconocimiento en Psicología/fisiología , Nódulo Pulmonar Solitario/diagnóstico por imagen , Análisis y Desempeño de Tareas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Curva ROC , Tomografía Computarizada por Rayos X/métodos
11.
Mol Pharm ; 10(5): 1623-43, 2013 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-23473440

RESUMEN

The Biopharmaceutical Classification System (BCS), which is a scientific approach to categorize active drug ingredient based on its solubility and intestinal permeability into one of the four classes, has been used to set the pharmaceutical quality standards for drug products in western society. However, it has received little attention in the area of Chinese herbal medicine (CHM). This is likely, in part, due to the presence of multiple active components as well as lack of standardization of CHM. In this report, we apply BCS classification to CHMs provisionally as a basis for establishing improved in vitro quality standards. Based on a top-200 drugs selling list in China, a total of 31 CHM products comprising 50 official active marker compounds (AMCs) were provisionally classified according to BCS. Information on AMC content and doses of these CHM products were retrieved from the Chinese Pharmacopoeia. BCS parameters including solubility and permeability of the AMCs were predicted in silico (ACD/Laboratories). A BCS classification of CHMs according to biopharmaceutical properties of their AMCs is demonstrated to be feasible in the current study and can be used to provide a minimum set of quality standards. Our provisional results showed that 44% of the included AMCs were classified as Class III (high solubility, low permeability), followed by Class II (26%), Class I (18%), and Class IV (12%). A similar trend was observed when CHMs were classified in accordance with the BCS class of AMCs. Most (45%) of the included CHMs were classified as Class III, followed by Class II (16%), Class I (10%), and Class IV (6%); whereas 23% of the CHMs were of mixed class due to the presence of multiple individual AMCs with different BCS classifications. Moreover, about 60% of the AMCs were classified as high-solubility compounds (Class I and Class III), suggesting an important role for an in vitro dissolution test in setting quality control standards ensuring consistent biopharmaceutical quality for the commercially available CHM products. That is, provisionally, more than half of the AMCs of the top-selling CHMs included in this study would be candidates for a bioequivalence (BE) biowaiver, based on WHO recommendations and EMEA guidelines. Thus a dissolution requirement on these AMCs would represent a significant advance in the pharmaceutical quality of CHM today.


Asunto(s)
Medicamentos Herbarios Chinos/clasificación , Medicamentos Herbarios Chinos/normas , China , Medicamentos Herbarios Chinos/farmacocinética , Humanos , Permeabilidad , Control de Calidad , Solubilidad , Equivalencia Terapéutica
12.
Int J Biochem Cell Biol ; 43(6): 905-12, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21419860

RESUMEN

A three amino acid sequence, Ser/Thr-Pro-Ser/Thr, was recently identified and characterized as a novel nuclear localization signal (Chuderland et al., 2008). The immediate-early gene product, early growth response-1 is a three zinc finger containing transcription factor implicated in a wide variety of pathologies, and has a bipartite nuclear localization domain identified two decades ago. Efficient nuclear localization of Egr-1 is vital to its function as a transcription factor. Interestingly, Egr-1 also contains a C-terminal SPS domain (residues 482-484 in murine Egr-1). We hypothesized that (482)SPS(484) may also serve as a novel nuclear localization signal in Egr-1. We found that this sequence directs Egr-1 to the nucleus in transfected Chinese hamster ovary cells and show by co-immunoprecipitation analysis that Egr-1 forms a complex with importin-7. (482)SPS(484) is required for Egr-1's interaction with importin-7. Moreover, importin-7 knockdown with RNAi showed that Egr-1 nuclear translocation is importin-7-dependent. This study demonstrates that the nuclear translocation of Egr-1 is partially dependent on (482)SPS(484) and involves importin-7, and sheds light on the molecular mechanisms regulating the cellular localization of this pathophysiologically important transcription factor.


Asunto(s)
Núcleo Celular/metabolismo , Proteína 1 de la Respuesta de Crecimiento Precoz/metabolismo , Miocitos del Músculo Liso/metabolismo , Transporte Activo de Núcleo Celular/genética , Animales , Células CHO , Cricetinae , Cricetulus , Proteína 1 de la Respuesta de Crecimiento Precoz/genética , Humanos , Carioferinas/genética , Carioferinas/metabolismo , Miocitos del Músculo Liso/patología , Señales de Localización Nuclear/genética , Prolina/genética , Unión Proteica/genética , Estructura Terciaria de Proteína/genética , Transporte de Proteínas/genética , ARN Interferente Pequeño/genética , Receptores Citoplasmáticos y Nucleares/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Serina/genética
13.
J Biol Chem ; 284(50): 35101-12, 2009 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-19843519

RESUMEN

Understanding the mechanisms governing cytokine control of growth factor expression in smooth muscle cells would provide invaluable insight into the molecular regulation of vascular phenotypes and create future opportunities for therapeutic intervention. Here, we report that the proinflammatory cytokine interleukin (IL)-1beta suppresses platelet-derived growth factor (PDGF)-D promoter activity and mRNA and protein expression in smooth muscle cells. NF-kappaB p65, induced by IL-1beta, interacts with a novel element in the PDGF-D promoter and inhibits PDGF-D transcription. Interferon regulatory factor-1 (IRF-1) is also induced by IL-1beta and binds to a different element upstream in the promoter. Immunoprecipitation and chromatin immunoprecipitation experiments showed that IL-1beta stimulates p65 interaction with IRF-1 and the accumulation of both factors at the PDGF-D promoter. Mutation of the IRF-1 and p65 DNA-binding elements relieved the promoter from IL-1beta-mediated repression. PDGF-D repression by IL-1beta involves histone deacetylation and interaction of HDAC-1 with IRF-1 and p65. HDAC-1 small interfering RNA ablates complex formation with IRF-1 and p65 and abrogates IRF-1 and p65 occupancy of the PDGF-D promoter. Thus, HDAC-1 is enriched at the PDGF-D promoter in cells exposed to IL-1beta and forms a cytokine-inducible gene-silencing complex with p65 and IRF-1.


Asunto(s)
Histona Desacetilasa 1/metabolismo , Factor 1 Regulador del Interferón/metabolismo , Interleucina-1beta/metabolismo , Linfocinas/metabolismo , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Regiones Promotoras Genéticas , Factor de Transcripción ReIA/metabolismo , Animales , Secuencia de Bases , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Silenciador del Gen , Histona Desacetilasa 1/genética , Humanos , Factor 1 Regulador del Interferón/genética , Interleucina-1beta/genética , Linfocinas/genética , Datos de Secuencia Molecular , Miocitos del Músculo Liso/citología , Miocitos del Músculo Liso/metabolismo , Factor de Crecimiento Derivado de Plaquetas/genética , Ratas , Factor de Transcripción ReIA/genética
14.
Blood ; 107(6): 2322-9, 2006 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-16189269

RESUMEN

Platelet-derived growth factor D-chain (PDGF-D) is the newest member of the PDGF family of mitogens and chemoattractants expressed in a wide variety of cell types, including vascular smooth muscle cells (SMCs). The molecular mechanisms regulating PDGF-D transcription are not known. Primer extension analysis mapped a single transcriptional start site to the ccAGCGC motif with several potential Ets motifs located upstream. Ets-1, but not Ets-1 bearing only the DNA-binding domain, activates the PDGF-D promoter and mRNA expression in SMCs. Ets site D3 ((-470)GGAT(-467)) is singly required for basal and Ets-1-inducible PDGF-D promoter-dependent expression. D3 supports the interaction of endogenous and recombinant Ets-1 and Sp1. Sp1, like Ets-1, induces PDGF-D transcription and mRNA expression, which is blocked by mutant Ets-1. H2O2 stimulates Ets-1, but not Sp1, and activates D3-dependent PDGF-D transcription. Ets-1 and Sp1 siRNA block peroxide-inducible PDGF-D expression. Angiotensin II (ATII) induction of PDGF-D and Ets-1 was blocked by prior incubation of the cells with PEG-catalase, but not BSA, indicating that ATII-inducible Ets-1 and PDGF-D expression is mediated via H2O2. Thus, 2 separate trans-acting factors regulate PDGF-D transcription, alone and in response to oxidative stress.


Asunto(s)
Angiotensina II/farmacología , Peróxido de Hidrógeno/farmacología , Linfocinas/genética , Factor de Crecimiento Derivado de Plaquetas/genética , Proteína Proto-Oncogénica c-ets-1/fisiología , Factor de Transcripción Sp1/fisiología , Transcripción Genética , Animales , Bovinos , Células Cultivadas , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Músculo Liso Vascular/citología , Estrés Oxidativo , Regiones Promotoras Genéticas , Proteína Proto-Oncogénica c-ets-1/genética , Ratas , Sitio de Iniciación de la Transcripción
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