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Tacrolimus, one of the macrolide calcineurin inhibitors, is the most frequently used immunosuppressant after transplantation. Long-term administration of tacrolimus leads to dyslipidemia and affects liver lipid metabolism. In this study, we investigated the mode of action and underlying mechanisms of this adverse reaction. Mice were administered tacrolimus (2.5 mg·kg-1·d-1, i.g.) for 10 weeks, then euthanized; the blood samples and liver tissues were collected for analyses. We showed that tacrolimus administration induced significant dyslipidemia and lipid deposition in mouse liver. Dyslipidemia was also observed in heart or kidney transplantation patients treated with tacrolimus. We demonstrated that tacrolimus did not directly induce de novo synthesis of fatty acids, but markedly decreased fatty acid oxidation (FAO) in AML12 cells. Furthermore, we showed that tacrolimus dramatically decreased the expression of HMGCS2, the rate-limiting enzyme of ketogenesis, with decreased ketogenesis in AML12 cells, which was responsible for lipid deposition in normal hepatocytes. Moreover, we revealed that tacrolimus inhibited forkhead box protein O1 (FoxO1) nuclear translocation by promoting FKBP51-FoxO1 complex formation, thus reducing FoxO1 binding to the HMGCS2 promoter and its transcription ability in AML12 cells. The loss of HMGCS2 induced by tacrolimus caused decreased ketogenesis and increased acetyl-CoA accumulation, which promoted mitochondrial protein acetylation, thereby resulting in FAO function inhibition. Liver-specific HMGCS2 overexpression via tail intravenous injection of AAV8-TBG-HMGCS2 construct reversed tacrolimus-induced mitochondrial protein acetylation and FAO inhibition, thus removing the lipid deposition in hepatocytes. Collectively, this study demonstrates a novel mechanism of liver lipid deposition and hyperlipidemia induced by long-term administration of tacrolimus, resulted from the loss of HMGCS2-mediated ketogenesis and subsequent FAO inhibition, providing an alternative target for reversing tacrolimus-induced adverse reaction.
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OBJECTIVE: To investigate the correlation between the human epidermal growth factor receptor-2-related genes (HRGs) and survival prognosis of bladder cancer and to construct a predictive model for survival prognosis of bladder cancer patients based on HRGs. METHODS: HRGs in bladder cancer were found by downloading bladder tumor tissue mRNA sequencing data and clinical data from the cancer genome atlas (TCGA), downloading HER-2 related genes from the molecular signatures database (MsigDB), and crossing the two databases. Further identifying HRGs associated with bladder cancer survival (P < 0.05) by using single and multi-factor Cox regression analysis and constructing HRGs risk score model (HRSM), the bladder cancer patients were categorized into high-risk and low-risk groups accor-ding to the median risk score. Survival analysis of the patients in high- and low-risk groups was conducted using R language and correlation of HRGs with clinical characteristics. A multi-factor Cox regression analysis was used to verify the independent factors affecting the prognosis of the patients with bladder cancer. The area under the curve (AUC) of the receiver operating characteristic curve (ROC) of HRSM was calculated, and a nomogram was constructed for survival prediction of the bladder cancer patients. Analysis of HRSM and patient immune cell infiltration correlation was made using the TIMER database. RESULTS: A total of 13 HRGs associated with patient survival were identified in this study. Five genes (BTC, CDC37, EGF, PTPRR and EREG) were selected for HRSM by multi-factor Cox regression analysis. The 5-year survival rate of the bladder cancer patients in the high-risk group was significantly lower than that of the patients in the low-risk group. High expression of PTPRR was found to be significantly and negatively correlated with tumor grade and stage by clinical correlation analysis, while EREG was found to be the opposite; Increased expression of EGF was associated with high grade, however, the high expression ofCDC37showed the opposite result. And no significant correlation was found between BTC expression and clinical features. Correlation analysis of HRSM with immune cells revealed a positive correlation between risk score and infiltration of dendritic cells, CD8+T cells, CD4+T cells, neutrophils and macrophages. CONCLUSION: HRGs have an important role in the prognosis of bladder cancer patients and may serve as new predictive biomarkers and potential targets for treatment.
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Factor de Crecimiento Epidérmico , Neoplasias de la Vejiga Urinaria , Humanos , Pronóstico , Neoplasias de la Vejiga Urinaria/genética , Nomogramas , Vejiga UrinariaRESUMEN
BACKGROUND: There is scant data on the association of the Pulsed wave-Doppler tissue imaging (PW-DTI)-derived tricuspid lateral annular peak systolic velocity (S') and poor short-term prognosis of patients with acute decompensated heart failure (ADHF). PATIENTS AND METHODS: A total number of 732 participants from the Heb-ADHF registry in China were divided into three groups according to the corresponding status of tricuspid S'. Demographic characteristics, comorbidities, physical examinations, lab tests, and medications were compared among the different groups. Different logistic regression models were utilized to gauge the relationship between S' and the risk of a composite of short-term all-cause mortality or 30-day heart failure (HF)-related rehospitalization. RESULTS: The number of composite outcome events identified in the study population was 85, with the short-term all-cause death coupled with 30-day HF readmission events reaching 23 and 62, respectively. As per the multivariable adjusted analysis, S' was inversely related to the risk of a composite outcome [<10 cm/s odds ratios (OR) 2.90, 95% confidence interval (CI):1.33-6.31; 10-11 cm/s OR 2.18, 95% CI: 1.10-4.33; p for trend = 0.006] in comparison with S' at >11 cm/s. When S' was analysed as a continuous variable, per 1 cm/s increase, the OR (95% CI) for a composite outcome was [0.87 (0.77-0.99), p = 0.028]. Area under curve (AUC) of S' for predicting outcome of ADHF was 0.631 (95%CI: 0.573-0.690, p < 0.01). Significant inverse association was also observed in left ventricular ejection fraction (LVEF) ≥40% subgroup. CONCLUSIONS: Inspite of the potential confounders, a more impaired tricuspid annular peak systolic velocity is associated with a poorer short-term prognosis of patients with ADHF.
This is the first comprehensive evaluation of tricuspid annular systolic velocity among patients with ADHF.Tricuspid annular systolic velocity could be a predictor of poor short-term prognosis in ADHF.Tricuspid annular systolic velocity should be considered in patients with ADHF at admission.
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Ecocardiografía Doppler , Insuficiencia Cardíaca , Humanos , Ecocardiografía Doppler/métodos , Pronóstico , Volumen Sistólico , Función Ventricular IzquierdaRESUMEN
BACKGROUND: Few prognostic risk scores (PRSs) have been routinely used in acute decompensated heart failure (ADHF). We, therefore, externally validated three published PRSs (3A3B, AHEAD, and OPTIME-CHF) and derived a new PRS to predict the short-term prognosis in ADHF. METHODS: A total of 4550 patients from the Heb-ADHF registry in China were randomly divided into the derivation and validation cohorts (3:2). Discrimination of each PRS was assessed by the area under the receiver operating characteristic curve (AUROC). Logistic regression was exploited to select the predictors and create the new PRS. The Hosmer-Lemeshow goodness-of-fit test was used to assess the calibration of the new PRS. RESULTS: The AUROCs of the 3A3B, AHEAD, and OPTIME-CHF score in the derivation cohort were 0.55 (95% CI 0.53-0.57), 0.54 (95% CI 0.53-0.56), and 0.56 (95% CI 0.54-0.57), respectively. After logistic regression analysis, the new PRS computed as 1 × (diastolic blood pressure < 80 mmHg) + 2 × (lymphocyte > 1.11 × 109/L) + 1 × (creatinine > 80 µmol/L) + 2 × (blood urea nitrogen > 21 mg/dL) + 1 × [BNP 500 to < 1500 pg/mL (NT-proBNP 2500 to < 7500 pg/mL)] or 3 × [BNP ≥ 1500 (NT-proBNP ≥ 7500) pg/mL] + 3 × (QRS fraction of electrocardiogram < 55%) + 4 × (ACEI/ARB not used) + 1 × (rhBNP used), with a better AUROC of 0.67 (95% CI 0.64-0.70) and a good calibration (Hosmer-Lemeshow χ2 = 3.366, P = 0.186). The results in validation cohort verified these findings. CONCLUSIONS: The short-term prognostic values of 3A3B, AHEAD, and OPTIME-CHF score in ADHF patients were all poor, while the new PRS exhibited potential predictive ability. We demonstrated the QRS fraction of electrocardiogram as a novel predictor for the short-term outcomes of ADHF for the first time. Our findings might help to recognize high-risk ADHF patients.
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Insuficiencia Cardíaca , Antagonistas de Receptores de Angiotensina , Inhibidores de la Enzima Convertidora de Angiotensina , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/terapia , Humanos , Péptido Natriurético Encefálico , Fragmentos de Péptidos , Pronóstico , Factores de RiesgoRESUMEN
OBJECTIVE: To explore the effectiveness of gadobenate dimeglumine (Gd-BOPTA)-enhanced magnetic resonance imaging (MRI) in predicting portal hypertension and high-risk esophageal varices (EV) in patients with hepatitis B cirrhosis. METHODS: In total, 71 and 30 patients comprising the training and validation groups, respectively, were enrolled in the study. Univariate and multivariate analyses were performed to detect their risk of developing high-risk EV to generate a formula for scoring EV. The relationships between the relative enhancement ratio (RE) of Gd-BOPTA-enhanced MRI and portal vein pressure were explored. RESULTS: Platelet count, portal vein width and RE were identified as independent predictors of high-risk EV. Based on these parameters, the EV score model were calculated as: -6.483 + 15.612 × portal vein width + 2.251 × RE - 0.176 × platelet count. The area under the receiver operating characteristic curve was 0.903. At a cut-off value of ≤ -2.74, the negative predictive value was 94.00%, while the positive predictive value was as high as 93.80% when the cut-off was set at > 4.00. Gd-BOPTA-enhanced MRI was effective in predicting portal pressure. Its accuracy was confirmed with the validation set. CONCLUSIONS: Gd-BOPTA-enhanced MRI was successfully applied to evaluate high-risk EV and portal hypertension. These results represent an accurate, non-invasive model for detecting high-risk EV, based on which we propose a cost-effective algorithm for EV management, eliminating the need to perform an endoscopy in all patients with cirrhosis.
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Medios de Contraste , Várices Esofágicas y Gástricas/diagnóstico por imagen , Hepatitis B/diagnóstico por imagen , Hipertensión Portal/diagnóstico por imagen , Cirrosis Hepática/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Meglumina/análogos & derivados , Compuestos Organometálicos , Adulto , Várices Esofágicas y Gástricas/virología , Femenino , Hepatitis B/complicaciones , Hepatitis B/virología , Virus de la Hepatitis B , Humanos , Hipertensión Portal/virología , Cirrosis Hepática/virología , Masculino , Persona de Mediana Edad , Presión Portal , Vena Porta/diagnóstico por imagen , Valor Predictivo de las Pruebas , Estudios Prospectivos , Curva ROC , Estudios Retrospectivos , Medición de Riesgo , Índice de Severidad de la EnfermedadRESUMEN
Achalasia is generally accepted as a condition associated with an increased risk for developing esophageal squamous cell carcinoma. In our paper, we introduced an achalasia patient combined with synchronous early esophageal neoplasms. We performed a combination of concurrent endoscopic submucosal dissection (ESD) and peroral endoscopic myotomy (POEM). No complications other than postoperative pain that needed morphine treatment for two days had occurred. Dysphagia was significantly improved. Neither reflux nor cough occurred. The short-term efficacy and safety of our case is favorable and suggests that concurrent ESD and POEM could be a treatment option to such patients.
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The stimulator of interferon genes (STING) is a key adaptor protein mediating innate immune defense against DNA viruses. To investigate the role of STING in acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF), we isolated primary peripheral blood mononuclear cells (PBMCs) from patients and healthy controls (HCs). Raw264.7 and A549 cells were infected with herpes simplex virus type 1 (HSV-1). Mice with bleomycin-induced lung fibrosis were infected with HSV-1 to stimulate acute exacerbation of the lung fibrosis. Global gene expression profiling revealed a substantial downregulation of interferon-regulated genes (downstream of STING) in the AE-IPF group compared with the HC and stable IPF groups. The PBMCs of the AE-IPF group showed significantly reduced STING protein levels, increased levels of endoplasmic reticulum (ER) stress markers, and elevated apoptosis. HSV-1 infection decreased STING expression and stimulated the ER stress pathways in Raw264.7 and A549 cells in a time- and dose-dependent manner. HSV-1 infection exacerbated the bleomycin-induced lung injury in mice. In the primary bone marrow-derived macrophages of mice treated with bleomycin and HSV-1, STING protein expression was substantially reduced; ER stress was stimulated. Tauroursodeoxycholic acid, a known inhibitor of ER stress, partially reversed those HSV-1-mediated adverse effects in mice with bleomycin-induced lung injury. STING levels in PBMCs increased after treatment in patients showing improvement but remained at low levels in patients with deterioration. Viral infection may trigger ER stress, resulting in STING deficiency and AE-IPF onset.
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Previous studies have shown that miR-454 plays an important role in a variety of biological processes in various human cancer cells. However, the underlying mechanisms of this microRNA in colorectal cancer (CRC) cells remain largely unknown. In the present study, we investigated the miR-454 role in CRC cell proliferation. We found that miR-454 expression is markedly upregulated in CRC tissues and CRC cells compared with the matched tumor adjacent tissues and the FHC normal colonic cell line. Ectopic expression of miR-454 promoted the proliferation and anchorage-independent growth of CRC cells, whereas inhibition of miR-454 reduced this effect. Bioinformatics analysis further revealed cylindromatosis (CYLD), a putative tumor suppressor as a potential target of miR-454. Data from luciferase reporter assays showed that miR-454 directly binds to the 3'-untranslated region (3'-UTR) of CYLD mRNA and repressed expression at both transcriptional and translational levels. In functional assays, CYLD-silenced in miR-454-in-transfected SW480 cells have positive effect to promote cell proliferation, suggesting that direct CYLD downregulation is required for miR-454-induced CRC cell proliferation. In sum, our data provide compelling evidence that miR-454 functions as an onco-miRNA, playing a crucial role in the promoting cell proliferation in CRC, and its oncogenic effect is mediated chiefly through direct suppression of CYLD expression.
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Movimiento Celular , Proliferación Celular , Neoplasias Colorrectales/patología , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Proteínas Supresoras de Tumor/antagonistas & inhibidores , Regiones no Traducidas 3' , Apoptosis , Western Blotting , Adhesión Celular , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Enzima Desubiquitinante CYLD , Humanos , Técnicas para Inmunoenzimas , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismoRESUMEN
Bevacizumab and panitumumab are human monoclonal antibodies with different targeting antigens, vascular endothelial growth factor, and epidermal growth factor receptor. This study examined the efficacy and safety of combining bevacizumab and panitumumab plus fluorouracil, leucovorin, and irinotecan (FOLFIRI) as the second-line therapy for patients with metastatic colorectal cancer (mCRC). Patients with mCRC, and previously failed with oxaliplatin-based chemotherapy, were given bevacizumab (3 mg/kg) and panitumumab (3 mg/kg) plus FOLFIRI every other week. From September 2008 to July 2012, 173 patients were included in the study. The response rate was 42.3 %, and the disease-controlled rate was 65.7 %. The median progression-free survival was 6.5 months, and the median overall survival was 15.4 months. Various adverse events (AE) including those known toxicities associated with antibody therapy were recorded. The overall AE rate was 64.5 % for grade 3-4. The treatment of combining bevacizumab and panitumumab plus FOLFIRI is effective and safe as a second-line therapy for patients with mCRC.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bevacizumab , Camptotecina/análogos & derivados , Camptotecina/uso terapéutico , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Supervivencia sin Enfermedad , Femenino , Fluorouracilo/uso terapéutico , Humanos , Leucovorina/uso terapéutico , Masculino , Persona de Mediana Edad , Panitumumab , Resultado del Tratamiento , Adulto JovenRESUMEN
AIM: To compare matrix metalloproteinase (MMP)-9 and tissue inhibitor of metalloproteinase (TIMP)-1 in gastric ulcer (GU) and chronic superficial gastritis (CSG). METHODS: This study enrolled 63 patients with GU and 25 patients with CSG. During upper gastroduodenal endoscopy, we took samples of gastric mucosa from the antrum and ulcer site from patients with GU, and samples of antral mucosa from patients with CSG. Mucosal biopsy tissues were cultured for 24 h, and the culture supernatant was measured for levels of MMP-9 and TIMP-1. After receiving eradication therapy for Helicobacter pylori (H. pylori) and 8 wk proton-pump inhibitor therapy for GU, follow-up endoscopy examination was performed after 6 mo and whenever severe symptoms occurred. RESULTS: Levels of MMP-9 and TIMP-1 at the ulcer site or in the antrum were significantly higher in GU than CSG patients. MMP-9 levels at the ulcer site were significantly higher than in the antrum in GU patients, and had a significantly positive correlation with TIMP-1. MMP-9 levels were significantly higher in H. pylori-positive than H. pylori-negative GU and CSG patients. Levels of MMP-9 or TIMP-1 at the ulcer site were associated with the histological severity of activity and inflammation. About 57 GU patients were followed up, and seven had GU recurrence. H. pyloriinfection and MMP-9 levels were risk factors for the recurrence of GU adjusted for age and sex by multiple logistic regression analysis. CONCLUSION: MMP-9 may perform an important function in gastric ulcer formation and recurrence.
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Mucosa Gástrica/enzimología , Metaloproteinasa 9 de la Matriz/metabolismo , Úlcera Gástrica/enzimología , Adulto , Anciano , Antibacterianos/uso terapéutico , Biomarcadores/metabolismo , Biopsia , Distribución de Chi-Cuadrado , Enfermedad Crónica , Quimioterapia Combinada , Endoscopía Gastrointestinal , Femenino , Mucosa Gástrica/microbiología , Mucosa Gástrica/patología , Gastritis/enzimología , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/enzimología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/aislamiento & purificación , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Inhibidores de la Bomba de Protones/uso terapéutico , Recurrencia , Factores de Riesgo , Úlcera Gástrica/tratamiento farmacológico , Úlcera Gástrica/microbiología , Úlcera Gástrica/patología , Factores de Tiempo , Técnicas de Cultivo de Tejidos , Inhibidor Tisular de Metaloproteinasa-1/metabolismo , Resultado del Tratamiento , Regulación hacia Arriba , Adulto JovenRESUMEN
OBJECTIVE: To investigate and obtain a more comprehensive view of the etiology and clinical features of acute pancreatitis (AP) in Shandong Province. METHODS: 1471 cases admitted to hospital for AP were studied and collected from the ten cities of Shandong Province from January 1992 to December 2002 retrospectively. Data of each enrolled patient was recorded in a standardized form. RESULTS: In the 1471 patients, the ratio of male: female was 854:617, and also the mean age of them and the range was 43.3 and from 13 - 82 years old. 1280 had mild AP, and 191 had sever AP. Cholelithiasis (20.2%), alcohol (17.3%) and diet-induced (12.4%) were the most frequent etiologic factors, followed by biliary tract infections (5.6%), hyperlipemia (2.3%), other factors (5.1%). But in about 36.1% cases, the etiology of AP still remains unexplained. In coastal regions, cholelithiasis is the most frequent factor but in interior regions alcohol ranked first. In male, a small predominance of alcohol over cholelithiasis was seen (27.4 vs.14.3%, P < 0.01); and in female, there was a clear predominance of cholelithiasis over alcohol (28.4 vs. 3.2%, P < 0.01). The complications of AP were pancreatic pseudocyst, ascites and peritonitis, pulmonary infections, multiple organ failure, diabetes mellitus-2 and shock, etc. according to their frequencies. CONCLUSIONS: Cholelithiasis, alcohol and diet-induced factor were main etiologic factors in Shandong Province, whereas cholelithiasis alone predominated in the females. In about 36.1% cases, the etiology remains unknown. So that more attention should be paid to study the etiology of AP.
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Pancreatitis/epidemiología , Pancreatitis/etiología , Enfermedad Aguda , Adulto , China/epidemiología , Colelitiasis/complicaciones , Dieta , Femenino , Humanos , Masculino , Pancreatitis Alcohólica/epidemiología , Estudios Retrospectivos , Distribución por SexoRESUMEN
Induction of differentiation of HL-60 human myeloid cells profoundly affected expression of calreticulin, a Ca(2+)-binding endoplasmic reticulum chaperone. Induction with Me(2)SO or retinoic acid reduced levels of calreticulin protein by approximately 60% within 4 days. Pulse-chase studies indicated that labeled calreticulin decayed at similar rates in differentiated and undifferentiated cells (t(12) approximately 4.6 days), but the biosynthetic rate was <10% of control after 4 days. Differentiation also induced a rapid decline in calreticulin mRNA levels (90% reduction after 1 day) without a decrease in transcript stability (t(12) approximately 5 h). Nuclear run-on analysis demonstrated rapid down-regulation of gene transcription (21% of control at 2 h). Differentiation also greatly reduced the Ca(2+) content of the cells (25% of control), although residual Ca(2+) pools remained sensitive to thapsigargin, ionomycin, and inositol trisphosphate. Progressive decreases were also observed in levels of calnexin and ERp57, whereas BiP/GRP78 and protein disulfide isomerase were only modestly affected. Ultrastructural studies showed a substantial reduction in endoplasmic reticulum content of the cells. Thus, terminal differentiation of myeloid cells was associated with decreased endoplasmic reticulum content, selective reductions in molecular chaperones, and diminished intracellular Ca(2+) stores, perhaps reflecting an endoplasmic reticulum remodeling program as a prominent feature of granulocytic differentiation.
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Proteínas de Unión al Calcio/genética , Diferenciación Celular/fisiología , Regulación Neoplásica de la Expresión Génica , Ribonucleoproteínas/genética , Calreticulina , Línea Celular , Retículo Endoplásmico/metabolismo , Chaperón BiP del Retículo Endoplásmico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HL-60 , Humanos , Cinética , Chaperonas Moleculares/genética , ARN Mensajero/genética , Ésteres del Ácido Sulfúrico/farmacología , Factores de Tiempo , Transcripción Genética/efectos de los fármacos , Tretinoina/farmacologíaRESUMEN
The p40(phox) protein, a regulatory component of the phagocyte NADPH oxidase, is preferentially expressed in cells of myeloid lineage. We investigated transcriptional regulation of the p40(phox) gene in HL-60 myeloid cells. Deletion analysis of approximately 6 kb of the 5'-flanking sequence of the gene demonstrated that the proximal 106 base pair of the promoter exhibited maximum reporter activity. This region contains 3 potential binding sites for PU.1, a myeloid-restricted member of the ets family of transcription factors. Mutation or deletion of each PU.1 site decreased promoter activity, and the level of activity mediated by each site correlated with its binding avidity for PU.1, as determined by gel shift competition assays. Mutation of all 3 sites abolished promoter activity in myeloid cells. PU.1-dependent expression was also observed in the Raji B-cell line, whereas the moderate level of promoter reporter activity in the nonmyeloid HeLa cell line was independent of PU.1. Chromatin immunoprecipitation assay demonstrated occupation of the PU.1 sites by PU.1 in vivo in HL-60 cells. Cotransfection of the pGL3-p40-106 reporter construct with a dominant-negative PU.1 mutant dramatically reduced promoter activity, whereas the overexpression of PU.1 increased promoter activity. Promoter activity and transcript levels of p40(phox) increased in HL-60 cells during dimethyl sulfoxide-induced differentiation toward the granulocyte phenotype, and this was associated with increased cellular levels of PU.1 protein. Our findings demonstrate that PU.1 binding at multiple sites is required for p40(phox) gene transcription in myeloid cells and that granulocytic differentiation is associated with the coordinated up-regulation of PU.1 and p40(phox) expression.