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1.
N Engl J Med ; 381(16): 1513-1523, 2019 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-31618539

RESUMEN

BACKGROUND: Heartburn that persists despite proton-pump inhibitor (PPI) treatment is a frequent clinical problem with multiple potential causes. Treatments for PPI-refractory heartburn are of unproven efficacy and focus on controlling gastroesophageal reflux with reflux-reducing medication (e.g., baclofen) or antireflux surgery or on dampening visceral hypersensitivity with neuromodulators (e.g., desipramine). METHODS: Patients who were referred to Veterans Affairs (VA) gastroenterology clinics for PPI-refractory heartburn received 20 mg of omeprazole twice daily for 2 weeks, and those with persistent heartburn underwent endoscopy, esophageal biopsy, esophageal manometry, and multichannel intraluminal impedance-pH monitoring. If patients were found to have reflux-related heartburn, we randomly assigned them to receive surgical treatment (laparoscopic Nissen fundoplication), active medical treatment (omeprazole plus baclofen, with desipramine added depending on symptoms), or control medical treatment (omeprazole plus placebo). The primary outcome was treatment success, defined as a decrease of 50% or more in the Gastroesophageal Reflux Disease (GERD)-Health Related Quality of Life score (range, 0 to 50, with higher scores indicating worse symptoms) at 1 year. RESULTS: A total of 366 patients (mean age, 48.5 years; 280 men) were enrolled. Prerandomization procedures excluded 288 patients: 42 had relief of their heartburn during the 2-week omeprazole trial, 70 did not complete trial procedures, 54 were excluded for other reasons, 23 had non-GERD esophageal disorders, and 99 had functional heartburn (not due to GERD or other histopathologic, motility, or structural abnormality). The remaining 78 patients underwent randomization. The incidence of treatment success with surgery (18 of 27 patients, 67%) was significantly superior to that with active medical treatment (7 of 25 patients, 28%; P = 0.007) or control medical treatment (3 of 26 patients, 12%; P<0.001). The difference in the incidence of treatment success between the active medical group and the control medical group was 16 percentage points (95% confidence interval, -5 to 38; P = 0.17). CONCLUSIONS: Among patients referred to VA gastroenterology clinics for PPI-refractory heartburn, systematic workup revealed truly PPI-refractory and reflux-related heartburn in a minority of patients. For that highly selected subgroup, surgery was superior to medical treatment. (Funded by the Department of Veterans Affairs Cooperative Studies Program; ClinicalTrials.gov number, NCT01265550.).


Asunto(s)
Reflujo Gastroesofágico/tratamiento farmacológico , Reflujo Gastroesofágico/cirugía , Pirosis/tratamiento farmacológico , Omeprazol/uso terapéutico , Inhibidores de la Bomba de Protones/uso terapéutico , Adulto , Baclofeno/uso terapéutico , Desipramina/uso terapéutico , Resistencia a Medicamentos , Quimioterapia Combinada , Femenino , Fundoplicación , Reflujo Gastroesofágico/complicaciones , Pirosis/etiología , Pirosis/cirugía , Humanos , Masculino , Persona de Mediana Edad , Relajantes Musculares Centrales/uso terapéutico , Calidad de Vida , Encuestas y Cuestionarios , Veteranos
2.
Lab Invest ; 100(1): 16-26, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31292541

RESUMEN

Gastroesophageal junction (GEJ) cancer remains a clinically significant disease in Western countries due to its increasing incidence, which mirrors that of esophageal cancer, and poor prognosis. To develop novel and effective approaches for prevention, early detection, and treatment of patients with GEJ cancer, a better understanding of the mechanisms driving pathogenesis and malignant progression of this disease is required. These efforts have been limited by the small number of available cell lines and appropriate preclinical animal models for in vitro and in vivo studies. We have established and characterized a novel GEJ cancer cell line, GEAMP, derived from the malignant pleural effusion of a previously treated GEJ cancer patient. Comprehensive genetic analyses confirmed a clonal relationship between GEAMP cells and the primary tumor. Targeted next-generation sequencing identified 56 nonsynonymous alterations in 51 genes including TP53 and APC, which are commonly altered in GEJ cancer. In addition, multiple copy-number alterations were found including EGFR and K-RAS gene amplifications and loss of CDKN2A and CDKN2B. Histological examination of subcutaneous flank xenografts in nude and NOD-SCID mice showed a carcinoma with mixed squamous and glandular differentiation, suggesting GEAMP cells contain a subpopulation with multipotent potential. Finally, pharmacologic inhibition of the EGFR signaling pathway led to downregulation of key downstream kinases and inhibition of cell proliferation in vitro. Thus, GEAMP represents a valuable addition to the limited number of bona fide GEJ cancer cell lines.


Asunto(s)
Adenocarcinoma/patología , Línea Celular Tumoral , Neoplasias Esofágicas/patología , Unión Esofagogástrica/patología , Derrame Pleural Maligno/patología , Adenocarcinoma/terapia , Animales , Receptores ErbB/antagonistas & inhibidores , Neoplasias Esofágicas/terapia , Resultado Fatal , Femenino , Humanos , Masculino , Ratones , Ratones Desnudos , Ratones SCID , Persona de Mediana Edad , Derrame Pleural Maligno/terapia , Ensayos Antitumor por Modelo de Xenoinjerto
3.
Gastroenterology ; 156(1): 130-144.e10, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30268789

RESUMEN

BACKGROUND & AIMS: Metaplastic glands buried under squamous epithelium are frequently detected in patients with Barrett esophagus (BE). This subsquamous intestinal metaplasia might be responsible for cancers that develop despite endoscopic surveillance and for metaplasia recurrences after endoscopic ablation. To determine whether reflux induces BE cells to undergo an epithelial-to-mesenchymal transition (EMT) that produces subsquamous intestinal metaplasia, we assessed EMT in BE cells exposed to acidic bile salts and in rat and human esophageal tissues. METHODS: We compared markers of EMT and cell motility in trans-well and 3-dimensional organotypic culture systems among dysplastic BE epithelial cell lines, nondysplastic telomerase-immortalized BE cell lines (BAR-T), and BAR-T cells exposed acutely or for 20 weeks to acidic bile salts. Vascular endothelial growth factor (VEGF) A was inhibited with a neutralizing antibody or CRISPR-Cas9n and VEGF receptor 2 was inhibited with SU1498 or shRNA, and cells were analyzed by immunohistochemistry, quantitative polymerase chain reaction, or immunoblotting for markers of VEGF signaling and EMT; cell motility was assessed by trans-well assay. We used immunohistochemistry and quantitative polymerase chain reaction to assess EMT markers in the columnar-lined esophagus of rats with surgically induced reflux esophagitis and in esophagectomy specimens from patients with BE. RESULTS: We detected features of EMT (decreased cadherin 1 [CDH1]; increased fibronectin 1, vimentin, and matrix metalloproteinase 2; and increased motility) in dysplastic BE epithelial cell lines and in BAR-T cells exposed for 20 weeks, but not in unexposed BAR-T cells. Acute acidic bile salt exposure induced expression of zinc finger E-box binding homeobox 1 and 2 (ZEB1/2) in BAR-T cells, which decreased their expression of CDH1 and increased motility; inhibitors of VEGF signaling blocked these effects. Columnar-lined esophagus of rats with reflux esophagitis had increased expression of ZEB1/2 and decreased expression of CDH1 compared with controls. Dysplastic BE tissues also had significantly increased levels of ZEB1 and significantly decreased levels of CDH1 compared with nondysplastic BE tissues. CONCLUSIONS: In BE cell lines, acidic bile salts induce EMT by VEGF signaling, which increases expression of ZEB1/2, repressors of CDH1. These observations suggest that reflux induces EMT in metaplastic BE tissues, which promotes development of subsquamous intestinal metaplasia.


Asunto(s)
Esófago de Barrett/metabolismo , Ácidos y Sales Biliares/toxicidad , Transformación Celular Neoplásica/inducido químicamente , Células Epiteliales/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Neoplasias Esofágicas/metabolismo , Esófago/efectos de los fármacos , Reflujo Gastroesofágico/metabolismo , Transducción de Señal/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Esófago de Barrett/genética , Esófago de Barrett/patología , Línea Celular , Movimiento Celular/efectos de los fármacos , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Modelos Animales de Enfermedad , Células Epiteliales/metabolismo , Células Epiteliales/patología , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patología , Esófago/metabolismo , Esófago/patología , Reflujo Gastroesofágico/genética , Reflujo Gastroesofágico/patología , Humanos , Ratas , Regulación hacia Arriba , Factor A de Crecimiento Endotelial Vascular/genética , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
4.
Gut ; 67(4): 606-615, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28442495

RESUMEN

OBJECTIVE: In previous studies using oesophageal squamous cells from patients with Barrett's oesophagus (normal oesophageal squamous (NES)-B cells) and from patients without Barrett's oesophagus (NES-G cells), we showed that acid and bile salts induced caudal-related homeobox transcription factor 2 (CDX2) expression only in NES-B cells. CDX2, a transcription factor required to form intestinal epithelium, is a target of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signalling, which can be inhibited by aspirin. We explored mechanisms underlying differences between NES-B and NES-G cells in CDX2 expression and effects of aspirin on that CDX2 expression. DESIGN: We exposed NES-B and NES-G cells to acid and bile salts, with and without aspirin, and evaluated effects on IκB-NF-κB-PKAc complex activation, p65 NF-κB subunit function, and CDX2 expression. RESULTS: In both NES-B and NES-G cells, acid and bile salts activated nicotinamide adenine dinucleotide phosphate oxidase to generate H2O2, which activated the IκB-NF-κB-PKAc complex. NES-B cells exhibited higher levels of phosphorylated IκB and p65 and greater NF-κB transcriptional activity than NES-G cells, indicating greater IκB-NF-κB-PKAc complex activation by acid and bile salts in NES-B cells, and p65 siRNA prevented their increased expression of CDX2. Aspirin blocked IκB phosphorylation, p65 nuclear translocation, CDX2 promoter activation and CDX2 expression induced by acid and bile salts in NES-B cells. CONCLUSIONS: Differences between NES-B and NES-G cells in NF-κB activation by acid and bile salts can account for their differences in CDX2 expression, and their CDX2 expression can be blocked by aspirin. These findings might explain why some patients with GORD develop Barrett's oesophagus while others do not, and why aspirin might protect against development of Barrett's oesophagus.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Aspirina/farmacología , Esófago de Barrett , Ácidos y Sales Biliares/metabolismo , Factor de Transcripción CDX2/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , FN-kappa B/efectos de los fármacos , Factor de Transcripción CDX2/metabolismo , Células Epiteliales/metabolismo , Humanos , FN-kappa B/metabolismo
5.
Gut ; 66(9): 1542-1554, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-27694141

RESUMEN

OBJECTIVE: In an earlier study wherein we induced acute reflux by interrupting proton pump inhibitor (PPI) therapy in patients with reflux oesophagitis (RO) healed by PPIs, we refuted the traditional concept that RO develops as an acid burn. The present study explored our alternative hypothesis that RO results from reflux-stimulated production of pro-inflammatory molecules mediated by hypoxia-inducible factors (HIFs). DESIGN: Using oesophageal biopsies taken from patients in our earlier study at baseline and at 1 and 2 weeks off PPIs, we immunostained for HIF-1α, HIF-2α and phospho-p65, and measured pro-inflammatory molecule mRNAs. We exposed human oesophageal squamous cell lines to acidic bile salts, and evaluated effects on HIF activation, p65 function, pro-inflammatory molecule production and immune cell migration. RESULTS: In patient biopsies, increased immunostaining for HIF-2α and phospho-p65, and increased pro-inflammatory molecule mRNA levels were seen when RO redeveloped 1 or 2 weeks after stopping PPIs. In oesophageal cells, exposure to acidic bile salts increased intracellular reactive oxygen species, which decreased prolyl hydroxylase function and stabilised HIF-2α, causing a p65-dependent increase in pro-inflammatory molecules; conditioned media from these cells increased T cell migration rates. HIF-2α inhibition by small hairpin RNA or selective small molecule antagonist blocked the increases in pro-inflammatory molecule expression and T cell migration induced by acidic bile salts. CONCLUSIONS: In patients developing RO, increases in oesophageal HIF-2α correlate with increased pro-inflammatory molecule expression. In oesophageal epithelial cells, acidic bile salts stabilise HIF-2α, which mediates expression of pro-inflammatory molecules. HIF-2α appears to have a role in RO pathogenesis. TRIAL REGISTRATION NUMBER: NCT01733810; Results.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Células Epiteliales/metabolismo , Esofagitis Péptica/metabolismo , Reflujo Gastroesofágico/metabolismo , Hipoxia/metabolismo , Línea Celular , Movimiento Celular/fisiología , Esofagitis Péptica/etiología , Esofagitis Péptica/patología , Reflujo Gastroesofágico/complicaciones , Reflujo Gastroesofágico/tratamiento farmacológico , Reflujo Gastroesofágico/patología , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Inhibidores de la Bomba de Protones/farmacología , Estadística como Asunto
6.
J Surg Oncol ; 116(3): 391-397, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28556988

RESUMEN

BACKGROUND AND OBJECTIVES: Gastric ischemic preconditioning has been proposed to improve blood flow and reduce the incidence of anastomotic complications following esophagectomy with gastric pull-up. This study aimed to evaluate the effect of prolonged ischemic preconditioning on the degree of neovascularization in the distal gastric conduit at the time of esophagectomy. METHODS: A retrospective review of a prospectively maintained database identified 30 patients who underwent esophagectomy. The patients were divided into three groups: control (no preconditioning, n = 9), partial (short gastric vessel ligation only, n = 8), and complete ischemic preconditioning (left and short gastric vessel ligation, n = 13). Microvessel counts were assessed, using immunohistologic analysis to determine the degree of neovascularization at the distal gastric margin. RESULTS: The groups did not differ in age, gender, BMI, pathologic stage, or cancer subtype. Ischemic preconditioning durations were 163 ± 156 days for partial ischemic preconditioning, compared to 95 ± 50 days for complete ischemic preconditioning (P = 0.2). Immunohistologic analysis demonstrated an increase in microvessel counts of 29% following partial ischemic preconditioning (P = 0.3) and 67% after complete ischemic preconditioning (P < 0.0001), compared to controls. CONCLUSIONS: Our study indicates that prolonged ischemic preconditioning is safe and does not interfere with subsequent esophagectomy. Complete ischemic preconditioning increased neovascularization in the distal gastric conduit.


Asunto(s)
Carcinoma/cirugía , Neoplasias Esofágicas/cirugía , Esofagectomía , Precondicionamiento Isquémico , Laparoscopía , Estómago/irrigación sanguínea , Anciano , Carcinoma/patología , Neoplasias Esofágicas/patología , Femenino , Humanos , Ligadura , Masculino , Persona de Mediana Edad , Neovascularización Fisiológica , Estudios Retrospectivos , Resultado del Tratamiento
7.
Gut ; 65(9): 1416-26, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-25986942

RESUMEN

OBJECTIVE: Barrett's metaplasia might develop if GORD causes oesophageal squamous cells to convert into columnar cells. Acid and bile exposures upregulate columnar differentiation genes like CDX2 in oesophageal squamous cells, but it is not known if such exposures downregulate squamous differentiation genes like SOX2. In addition to acid and bile, patients with GORD also have high oesophageal concentrations of nitric oxide (NO). This study aims to determine how acid, bile salts and NO affect genes that influence oesophageal cell phenotype. DESIGN: Oesophageal squamous cells from patients with Barrett's oesophagus were exposed to acidic bile salts or NOC-9 (an NO donor). SOX2, p63 (squamous transcription factor) and CDX2 mRNAs were measured by quantitative RT-PCR. SOX2 and its regulatory Akt pathway proteins were evaluated by western blotting. S-nitrosylation by NO was blocked by dithiothreitol. Immunohistochemistry for SOX2 was performed on the oesophagus of rats with surgically induced GORD which were fed diets with and without nitrite supplementation. RESULTS: In oesophageal squamous cells, NO profoundly decreased SOX2 protein and caused a significantly greater decrease in SOX2 mRNA than did acidic bile salts. NO also decreased p63 and increased CDX2 expression. NO caused S-nitrosylation of Akt, blocking its phosphorylation. Akt pathway inhibition by LY294002 or Akt siRNA reduced SOX2 mRNA. Rats fed with nitrite-supplemented diets exhibited weaker SOX2 oesophageal staining than rats fed with normal diets. CONCLUSIONS: In oesophageal squamous cells, NO blocks SOX2 expression through Akt S-nitrosylation. NO also increases CDX2 and decreases p63 expression. By triggering molecular events preventing squamous differentiation while promoting intestinal differentiation, NO might contribute to Barrett's pathogenesis.


Asunto(s)
Esófago de Barrett , Factor de Transcripción CDX2/metabolismo , Células Epiteliales , Reflujo Gastroesofágico , Óxido Nítrico/metabolismo , Factores de Transcripción SOXB1/metabolismo , Triazenos/metabolismo , Animales , Esófago de Barrett/etiología , Esófago de Barrett/metabolismo , Esófago de Barrett/patología , Ácidos y Sales Biliares/metabolismo , Diferenciación Celular , Línea Celular , Modelos Animales de Enfermedad , Células Epiteliales/metabolismo , Células Epiteliales/patología , Esófago/patología , Reflujo Gastroesofágico/complicaciones , Reflujo Gastroesofágico/metabolismo , Reflujo Gastroesofágico/patología , Humanos , Masculino , ARN Mensajero/metabolismo , Ratas , Transducción de Señal/fisiología
9.
JAMA ; 315(19): 2104-12, 2016 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-27187303

RESUMEN

IMPORTANCE: The histologic changes associated with acute gastroesophageal reflux disease (GERD) have not been studied prospectively in humans. Recent studies in animals have challenged the traditional notion that reflux esophagitis develops when esophageal surface epithelial cells are exposed to lethal chemical injury from refluxed acid. OBJECTIVE: To evaluate histologic features of esophageal inflammation in acute GERD to study its pathogenesis. DESIGN, SETTING, AND PARTICIPANTS: Patients from the Dallas Veterans Affairs Medical Center who had reflux esophagitis successfully treated with proton pump inhibitors (PPIs) began 24-hour esophageal pH and impedance monitoring and esophagoscopy (including confocal laser endomicroscopy [CLE]) with biopsies from noneroded areas of distal esophagus at baseline (taking PPIs) and at 1 week and 2 weeks after stopping the PPI medication. Enrollment began May 2013 and follow-up ended July 2015. INTERVENTIONS: PPIs stopped for 2 weeks. MAIN OUTCOMES AND MEASURES: Twelve patients (men, 11; mean age, 57.6 year [SD, 13.1]) completed the study. Primary outcome was change in esophageal inflammation 2 weeks after stopping the PPI medication, determined by comparing lymphocyte, eosinophil, and neutrophil infiltrates (each scored on a 0-3 scale) in esophageal biopsies. Also evaluated were changes in epithelial basal cell and papillary hyperplasia, surface erosions, intercellular space width, endoscopic grade of esophagitis, esophageal acid exposure, and mucosal impedance (an index of mucosal integrity). RESULTS: At 1 week and 2 weeks after discontinuation of PPIs, biopsies showed significant increases in intraepithelial lymphocytes, which were predominantly T cells (median [range]: 0 (0-2) at baseline vs 1 (1-2) at both 1 week [P = .005] and 2 weeks [P = .002]); neutrophils and eosinophils were few or absent. Biopsies also showed widening of intercellular spaces (confirmed by CLE), and basal cell and papillary hyperplasia developed without surface erosions. Two weeks after stopping the PPI medication, esophageal acid exposure increased (median: 1.2% at baseline to 17.8% at 2 weeks; Δ, 16.2% [95% CI, 4.4%-26.5%], P = .005), mucosal impedance decreased (mean: 2671.3 Ω at baseline to 1508.4 Ω at 2 weeks; Δ, 1162.9 Ω [95% CI, 629.9-1695.9], P = .001), and all patients had evidence of esophagitis. CONCLUSIONS AND RELEVANCE: In this preliminary study of 12 patients with severe reflux esophagitis successfully treated with PPI therapy, stopping PPI medication was associated with T lymphocyte-predominant esophageal inflammation and basal cell and papillary hyperplasia without loss of surface cells. If replicated, these findings suggest that the pathogenesis of reflux esophagitis may be cytokine-mediated rather than the result of chemical injury. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01733810.


Asunto(s)
Esofagitis Péptica/patología , Esófago/patología , Reflujo Gastroesofágico/patología , 2-Piridinilmetilsulfinilbencimidazoles/uso terapéutico , Biopsia , Eosinófilos/patología , Esofagitis Péptica/tratamiento farmacológico , Esofagitis Péptica/etiología , Femenino , Reflujo Gastroesofágico/complicaciones , Humanos , Linfocitos/patología , Masculino , Persona de Mediana Edad , Neutrófilos/patología , Omeprazol/uso terapéutico , Pantoprazol , Inhibidores de la Bomba de Protones/uso terapéutico , Privación de Tratamiento
10.
Am J Physiol Gastrointest Liver Physiol ; 309(3): G146-61, 2015 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-26045618

RESUMEN

Metaplastic epithelial cells of Barrett's esophagus transformed by the combination of p53-knockdown and oncogenic Ras expression are known to activate signal transducer and activator of transcription 3 (STAT3). When phosphorylated at tyrosine 705 (Tyr705), STAT3 functions as a nuclear transcription factor that can contribute to oncogenesis. STAT3 phosphorylated at serine 727 (Ser727) localizes in mitochondria, but little is known about mitochondrial STAT3's contribution to carcinogenesis in Barrett's esophagus, which is the focus of this study. We introduced a constitutively active variant of human STAT3 (STAT3CA) into the following: 1) non-neoplastic Barrett's (BAR-T) cells; 2) BAR-T cells with p53 knockdown; and 3) BAR-T cells that express oncogenic H-Ras(G12V). STAT3CA transformed only the H-Ras(G12V)-expressing BAR-T cells (evidenced by loss of contact inhibition, formation of colonies in soft agar, and generation of tumors in immunodeficient mice), and did so in a p53-independent fashion. The transformed cells had elevated levels of both mitochondrial (Ser727) and nuclear (Tyr705) phospho-STAT3. Introduction of a STAT3CA construct with a mutated tyrosine phosphorylation site into H-Ras(G12V)-expressing Barrett's cells resulted in high levels of mitochondrial phospho-STAT3 (Ser727) with little or no nuclear phospho-STAT3 (Tyr705), and the cells still formed tumors in immunodeficient mice. Thus tyrosine phosphorylation of STAT3 is not required for tumor formation in Ras-expressing Barrett's cells. We conclude that mitochondrial STAT3 (Ser727) can contribute to oncogenesis in Barrett's cells that express oncogenic Ras. These findings suggest that agents targeting STAT3 might be useful for chemoprevention in patients with Barrett's esophagus.


Asunto(s)
Esófago de Barrett , Mitocondrias/metabolismo , Proteína Oncogénica p21(ras)/metabolismo , Factor de Transcripción STAT3/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Esófago de Barrett/metabolismo , Esófago de Barrett/patología , Línea Celular Transformada , Transformación Celular Neoplásica/metabolismo , Células Epiteliales/metabolismo , Células Epiteliales/patología , Técnicas de Silenciamiento del Gen , Humanos , Ratones , Transducción de Señal/fisiología
11.
Gastroenterology ; 146(2): 461-72.e6, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24120473

RESUMEN

BACKGROUND & AIMS: Tumor cells express vascular endothelial growth factor (VEGF), which induces angiogenesis. VEGF also activates VEGF receptors (VEGFRs) on or within tumor cells to promote their proliferation in an autocrine fashion. We studied the mechanisms of autocrine VEGF signaling in Barrett's esophagus cells. METHODS: Using Barrett's epithelial cell lines, we measured VEGF and VEGFR messenger RNA and protein, and studied the effects of VEGF signaling on cell proliferation and VEGF secretion. We studied the effects of inhibiting factors in this pathway on levels of phosphorylated phospholipase Cγ1 (PLCG1), protein kinase C, and extracellular signal-regulated kinases (ERK)1/2. We performed immunohistochemical analysis of phosphorylated VEGFR2 on esophageal adenocarcinoma tissues. We studied effects of sunitinib, a VEGFR2 inhibitor, on proliferation of neoplastic cells and growth of xenograft tumors in mice. RESULTS: Neoplastic and non-neoplastic Barrett's cells expressed VEGF and VEGFR2 messenger RNA and protein, with higher levels in neoplastic cells. Incubation with recombinant human VEGF significantly increased secretion of VEGF protein and cell number; knockdown of PLCG1 markedly reduced the recombinant human VEGF-stimulated increase in levels of phosphorylated PLCG1 and phosphorylated ERK1/2 in neoplastic cells. Esophageal adenocarcinoma tissues showed immunostaining for phosphorylated VEGFR2. Sunitinib inhibited VEGF signaling in neoplastic cells and reduced weight and volume of xenograft tumors in mice. CONCLUSIONS: Neoplastic and non-neoplastic Barrett's epithelial cells have autocrine VEGF signaling. In neoplastic Barrett's cells, VEGF activation of VEGFR2 initiates a PLCG1-protein kinase C-ERK pathway that promotes proliferation and is self-sustaining (by causing more VEGF production). Strategies to reduce autocrine VEGF signaling (eg, with sunitinib) might be used to prevent or treat cancer in patients with Barrett's esophagus.


Asunto(s)
Adenocarcinoma/metabolismo , Esófago de Barrett/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias Esofágicas/metabolismo , Lesiones Precancerosas/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Animales , Antineoplásicos/uso terapéutico , Comunicación Autocrina , Esófago de Barrett/patología , Biomarcadores/metabolismo , Línea Celular , Proliferación Celular , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/patología , Femenino , Humanos , Inmunohistoquímica , Indoles/uso terapéutico , Sistema de Señalización de MAP Quinasas/fisiología , Ratones , Fosfolipasa C gamma/metabolismo , Fosforilación , Lesiones Precancerosas/patología , Proteína Quinasa C/metabolismo , Pirroles/uso terapéutico , Reacción en Cadena en Tiempo Real de la Polimerasa , Sunitinib , Resultado del Tratamiento
12.
Gut ; 63(7): 1042-52, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24048734

RESUMEN

OBJECTIVE: Oesophagitis might result from the effects of chemokines produced by oesophageal cells in response to gastro-oesophageal reflux, and not solely from the direct, caustic effects of refluxed gastric juice. Proton pump inhibitors (PPI) can block chemokine production through mechanisms independent of their antisecretory effects. We studied omeprazole effects on chemokine production by oesophageal epithelial cells exposed to acidic bile salts. DESIGN: Human primary and telomerase-immortalised oesophageal squamous cells were exposed to acidic bile salt medium with or without omeprazole pretreatment. Interleukin (IL)-8 expression was determined by RT-PCR and ELISA. IL-8 promoter activity was measured by luciferase reporter assay. Binding of NF-κB and AP-1 subunits to the IL-8 promoter was assessed by chromatin immunoprecipitation (ChIP) assay. Immune cell migration induced by conditioned medium was determined by a double-chamber migration assay system. RESULTS: Acidic bile salt medium caused oesophageal epithelial cells to express IL-8 mRNA and protein by activating the IL-8 promoter through NF-κB and AP-1 binding. Omeprazole inhibited that acidic bile salt-stimulated IL-8 expression by blocking the nuclear translocation of p65 (an NF-κB subunit), and by blocking the binding of p65, c-jun and c-fos (AP-1 subunits) to the IL-8 promoter. Omeprazole also blocked the ability of conditioned medium from cells exposed to acidic bile salts to induce immune cell migration. CONCLUSIONS: In oesophageal squamous epithelial cells, omeprazole inhibits IL-8 expression through effects on NF-κB and AP-1 that are entirely independent of effects on gastric acid secretion. These previously unrecognised PPI effects might contribute to the healing of reflux oesophagitis.


Asunto(s)
Ácidos y Sales Biliares/farmacología , Células Epiteliales/efectos de los fármacos , Esófago/efectos de los fármacos , Interleucina-8/antagonistas & inhibidores , Omeprazol/farmacología , Inhibidores de la Bomba de Protones/farmacología , Biomarcadores/metabolismo , Línea Celular , Células Cultivadas , Inmunoprecipitación de Cromatina , Ensayo de Inmunoadsorción Enzimática , Células Epiteliales/metabolismo , Esofagitis Péptica/etiología , Esófago/metabolismo , Femenino , Humanos , Interleucina-8/metabolismo , Masculino , Persona de Mediana Edad , FN-kappa B/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Transcripción AP-1/metabolismo
13.
Am J Physiol Gastrointest Liver Physiol ; 307(2): G129-39, 2014 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-24852569

RESUMEN

Hydrophobic bile acids like deoxycholic acid (DCA), which cause oxidative DNA damage and activate NF-κB in Barrett's metaplasia, might contribute to carcinogenesis in Barrett's esophagus. We have explored mechanisms whereby ursodeoxycholic acid (UDCA, a hydrophilic bile acid) protects against DCA-induced injury in vivo in patients and in vitro using nonneoplastic, telomerase-immortalized Barrett's cell lines. We took biopsies of Barrett's esophagus from 21 patients before and after esophageal perfusion with DCA (250 µM) at baseline and after 8 wk of oral UDCA treatment. DNA damage was assessed by phospho-H2AX expression, neutral CometAssay, and phospho-H2AX nuclear foci formation. Quantitative PCR was performed for antioxidants including catalase and GPX1. Nrf2, catalase, and GPX1 were knocked down with siRNAs. Reporter assays were performed using a plasmid construct containing antioxidant responsive element. In patients, baseline esophageal perfusion with DCA significantly increased phospho-H2AX and phospho-p65 in Barrett's metaplasia. Oral UDCA increased GPX1 and catalase levels in Barrett's metaplasia and prevented DCA perfusion from inducing DNA damage and NF-κB activation. In cells, DCA-induced DNA damage and NF-κB activation was prevented by 24-h pretreatment with UDCA, but not by mixing UDCA with DCA. UDCA activated Nrf2 signaling to increase GPX1 and catalase expression, and protective effects of UDCA pretreatment were blocked by siRNA knockdown of these antioxidants. UDCA increases expression of antioxidants that prevent toxic bile acids from causing DNA damage and NF-κB activation in Barrett's metaplasia. Elucidation of this molecular pathway for UDCA protection provides rationale for clinical trials on UDCA for chemoprevention in Barrett's esophagus.


Asunto(s)
Anticarcinógenos/uso terapéutico , Antioxidantes/uso terapéutico , Esófago de Barrett/tratamiento farmacológico , Daño del ADN/efectos de los fármacos , Ácido Desoxicólico/toxicidad , Células Epiteliales/efectos de los fármacos , Neoplasias Esofágicas/prevención & control , Esófago/efectos de los fármacos , Ácido Ursodesoxicólico/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Antioxidantes/metabolismo , Esófago de Barrett/genética , Esófago de Barrett/metabolismo , Esófago de Barrett/patología , Catalasa/genética , Catalasa/metabolismo , Línea Celular , Células Epiteliales/metabolismo , Células Epiteliales/patología , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patología , Esófago/metabolismo , Esófago/patología , Femenino , Glutatión Peroxidasa/genética , Glutatión Peroxidasa/metabolismo , Histonas/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Fosforilación , Interferencia de ARN , ARN Mensajero/metabolismo , Factores de Tiempo , Factor de Transcripción ReIA/metabolismo , Transfección , Resultado del Tratamiento , Regulación hacia Arriba , Glutatión Peroxidasa GPX1
14.
Am J Surg ; 232: 112-117, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38320887

RESUMEN

BACKGROUND: The consequences of failed nonoperative management of appendicitis in older patients have not been described. METHODS: We used the 2004-2017 National Inpatient Sample to identify acute appendicitis patients managed nonoperatively (<65 years old: 32,469; ≥65 years old: 11,265). Outcomes included morbidity, length of stay (LOS), inpatient costs, and discharge to skilled facilities. Differences were estimated using propensity scores. RESULTS: For patients <65, nonoperative failure was associated with increased morbidity (7 â€‹% [95 â€‹% CI 6.9 â€‹%-8.1 â€‹%]), LOS (3 day [95 â€‹% CI 3-4]), costs ($9015 [95 â€‹% CI $8216- $9446]), and discharges to skilled facilities (1 â€‹% [95 â€‹% CI 0.9 â€‹%-1.6 â€‹%]) compared to successful nonoperative treatment. Patients ≥65 had differences in morbidity (14 â€‹% [95 â€‹% CI 13.6 â€‹%-16.2 â€‹%]), LOS (6 days [95 â€‹% CI 5-6]), costs ($15,964 [95 â€‹% CI $15,181- $17,708]), and discharges to skilled facilities (12 â€‹% [95 â€‹% CI: 10.0 â€‹%-13.3]) compared to nonoperative success. CONCLUSIONS: Nonoperative management of appendicitis should be approached cautiously for older adults.


Asunto(s)
Apendicitis , Tiempo de Internación , Insuficiencia del Tratamiento , Humanos , Apendicitis/terapia , Apendicitis/economía , Anciano , Masculino , Femenino , Persona de Mediana Edad , Tiempo de Internación/estadística & datos numéricos , Estados Unidos , Factores de Edad , Adulto , Apendicectomía/economía , Anciano de 80 o más Años , Estudios Retrospectivos , Puntaje de Propensión , Alta del Paciente/estadística & datos numéricos
15.
Surgery ; 175(2): 258-264, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38040596

RESUMEN

BACKGROUND: The purpose of this study was to (1) compare post-treatment outcomes of operative and nonoperative management of acute appendicitis in multi-morbid patients and (2) evaluate the generalizability of prior clinical trials by determining whether outcomes differ in multi-morbid patients compared to the young and healthy patients who resemble prior clinical trial participants. METHODS: We conducted a retrospective cohort study using the National Inpatient Sample from 2004 to 2017. We included 368,537 patients with acute, uncomplicated appendicitis who were classified as having 0 or 2+ comorbidities. We compared inpatient morbidity, mortality, length of stay, and costs using propensity scores. Unmeasured confounding was addressed with probabilistic sensitivity analysis. RESULTS: Overall, 5% of patients without comorbidities were treated nonoperatively versus 20% of multi-morbid patients. Compared to surgery, nonoperative management was associated with a 3.5% decrease in complications (95% confidence interval 3%-4%) for multi-morbid patients, but there was no significant difference for patients without comorbidity. However, nonoperative management was associated with a 1.5% increase in mortality for multimorbid patients (95% confidence interval 1.3%-1.7%). Costs and length of stay were lower for all patients treated with surgery. Probabilistic sensitivity analysis showed that results were robust to the effects of unmeasured confounding. CONCLUSION: Our results raise concerns about the generalizability of clinical trials that compared nonoperative and operative management of appendicitis because (1) those trials enrolled mostly young and healthy patients, and (2) results in multi-morbid patients differ from outcomes in younger and healthier patients.


Asunto(s)
Apendicitis , Humanos , Enfermedad Aguda , Apendicitis/terapia , Morbilidad , Estudios Retrospectivos , Resultado del Tratamiento , Ensayos Clínicos como Asunto
16.
Plants (Basel) ; 12(4)2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36840314

RESUMEN

Vietnam is extremely rich in biodiversity, with a remarkable range of habitats and more than 13,500 species of vascular plants recorded for the flora of Vietnam. This number represents about 3 to 5% of the world's diversity of vascular plants. Over the past 30 years, there were two important documents on the vascular plants of Vietnam published, An Illustrated Flora of Vietnam (IFV) and Checklist of Plant Species of Vietnam (CPSV). During the past half century, the advent of molecular phylogenetics has witnessed dramatic changes in the classifications of vascular plants, and some modern classification systems of vascular plants have been established, e.g., PPG I, GPG, and APG. However, the vascular plants of Vietnam have not yet been classified according to these modern classification systems. In this paper, we present the history of the classification of vascular plants in Vietnam, compare the circumscription of all families of vascular plants occurring within Vietnam in IFV, CPSV, and the modern classification systems when applicable, and summarize familial assignments of all controversial genera in the different classifications. Furthermore, we also arrange the 37 families of lycophytes and ferns occurring within Vietnam according to the latest classification system (PPG I) and the 8 families of gymnosperms according to the latest Christenhusz's system (GPG). The 246 families of angiosperms are arranged according to the fourth edition of the latest Angiosperm Phylogeny Group (APG IV). These results are the foundation stones and would be helpful for future research on the flora of Vietnam and the arrangement of plant collections in Vietnamese herbaria based on the updated classifications.

17.
Ecol Evol ; 12(10): e9377, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36203634

RESUMEN

Matsumurasca onukii (Matsuda, R. (1952). Oyo-Kontyu Tokyo, 8(1): 19-21), one of the dominant pests in major tea production areas in Asia, currently is known to occur in Japan, Vietnam, and China, and severely threatens tea production, quality, and international trade. To elucidate the population genetic structure of this species, 1633 single nucleotide polymorphisms (SNPs) and 18 microsatellite markers (SSRs) were used to genotype samples from 27 sites representing 18 geographical populations distributed throughout the known range of the species in East Asia. Analyses of both SNPs and SSRs showed that M. onukii populations in Yunnan exhibit high-genetic differentiation and structure compared with the other populations. The Kagoshima (JJ) and Shizuoka (JS) populations from Japan were separated from populations from China by SNPs, but clustered with populations from Jinhua (JH), Yingde (YD), Guilin (GL), Fuzhou (FZ), Hainan (HQ), Leshan (CT), Chongqing (CY), and Zunyi (ZY) tea plantations in China and the Vietnamese Vinh Phuc (VN) population based on the SSR data. In contrast, CT, CY, ZY, and Shaanxi (SX) populations clustered together based on SNPs, but were separated by SSRs. Both marker datasets identified significant geographic differentiation among the 18 populations. Various environmental and anthropogenic factors, including geographical barriers to migration, human transport of hosts (Camellia sinesis [L.] O. Kuntze) and adaptation of M. onukii to various local climatic zones possibly account for the rapid spread of this pest in Asia. The results demonstrate that SNPs from high-throughput genotyping data can be used to reveal subtle genetic substructure at broad scales in r-strategist insects.

18.
Surg Endosc ; 25(6): 1969-74, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21136094

RESUMEN

BACKGROUND: Laparoscopic cholecystectomy (LC) is a common surgical procedure performed by surgical residents under the supervision of attending surgeons. There is a perception that performance of LC in a facility with a surgical training program provides a safer environment due to the presence of an assistant surgeon. The aim of this study was to compare the rate of bile duct injury, conversion, and mortality between hospitals with surgical residency programs (Group I) and hospitals without surgical training programs (Group II). METHODS: ICD-9 diagnosis and procedure codes were used to extract and analyze LC procedures from the Florida State Inpatient Database from 1997 through 2006. Bile duct injury was indicated by the code for a biliary reconstruction procedure performed during the same admission. Hospitals with surgical training programs were identified by participation in the Electronic Residency Application Service (ERAS) and verified by contact with each hospital. RESULTS: Between 1997 and 2006 there were 234,220 LCs identified, with 17,596 performed by Group I and 213,906 performed by Group II. Rate of BDI for Group I and Group II was 0.24 and 0.26%, respectively (p=0.71). There was a significant difference noted in emergency and urgent admission rates (65.6% for Group I vs. 77.2% for Group II; p<0.001) and conversion (9.1% for Group I vs. 7.5% for Group II; p<0.001). Mortality was 0.44% for Group I and 0.55% for Group II (p=0.060). CONCLUSION: Our data suggest that bile duct injury rates are not influenced by the presence of a surgical residency program. In addition, there was no significant difference in mortality for LC at hospitals with surgical residencies when compared to hospitals without surgical residencies. A significant difference was noted in admission type and conversion rate but this did not appear to affect the rate of bile duct injury.


Asunto(s)
Conductos Biliares/lesiones , Colecistectomía Laparoscópica/efectos adversos , Competencia Clínica , Hospitales de Enseñanza/estadística & datos numéricos , Complicaciones Intraoperatorias/epidemiología , Adulto , Anciano , Femenino , Cirugía General/educación , Mortalidad Hospitalaria , Humanos , Internado y Residencia , Modelos Logísticos , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
19.
Mol Cancer Ther ; 20(10): 1904-1915, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34376577

RESUMEN

Itraconazole, an FDA-approved antifungal, has antitumor activity against a variety of cancers. We sought to determine the effects of itraconazole on esophageal cancer and elucidate its mechanism of action. Itraconazole inhibited cell proliferation and induced G1-phase cell-cycle arrest in esophageal squamous cell carcinoma and adenocarcinoma cell lines. Using an unbiased kinase array, we found that itraconazole downregulated protein kinase AKT phosphorylation in OE33 esophageal adenocarcinoma cells. Itraconazole also decreased phosphorylation of downstream ribosomal protein S6, transcriptional expression of the upstream receptor tyrosine kinase HER2, and phosphorylation of upstream PI3K in esophageal cancer cells. Lapatinib, a tyrosine kinase inhibitor that targets HER2, and siRNA-mediated knockdown of HER2 similarly suppressed cancer cell growth in vitro Itraconazole significantly inhibited growth of OE33-derived flank xenografts in mice with detectable levels of itraconazole and its primary metabolite, hydroxyitraconazole, in esophagi and tumors. HER2 total protein and phosphorylation of AKT and S6 proteins were decreased in xenografts from itraconazole-treated mice compared to xenografts from placebo-treated mice. In an early phase I clinical trial (NCT02749513) in patients with esophageal cancer, itraconazole decreased HER2 total protein expression and phosphorylation of AKT and S6 proteins in tumors. These data demonstrate that itraconazole has potent antitumor properties in esophageal cancer, partially through blockade of HER2/AKT signaling.


Asunto(s)
Neoplasias Esofágicas/tratamiento farmacológico , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Itraconazol/farmacología , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Receptor ErbB-2/antagonistas & inhibidores , Animales , Apoptosis , Ciclo Celular , Movimiento Celular , Proliferación Celular , Inhibidores del Citocromo P-450 CYP3A/farmacología , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago/metabolismo , Carcinoma de Células Escamosas de Esófago/patología , Femenino , Humanos , Itraconazol/farmacocinética , Dosis Máxima Tolerada , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Pronóstico , Distribución Tisular , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
20.
Surg Endosc ; 24(6): 1462-7, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20033709

RESUMEN

BACKGROUND: Laparoscopic adrenalectomy is the treatment of choice for most adrenal lesions. Concerns have persisted about its application to large pheochromocytomas due to reports of hemodynamic instability, difficult dissection, and tumor spillage. METHODS: Thirty patients underwent laparoscopic adrenalectomy for unilateral pheochromocytoma between 1998 and 2006. Outcome measures including operative time, blood loss, intraoperative hemodynamic instability, conversion rate, complications, and disease recurrence were analyzed based on tumor size. RESULTS: Twenty-two patients had small tumors and eight had large lesions. These groups did not differ in terms of operative time, blood loss, conversion rate, length of stay or complication rate. Intraoperative hemodynamic instability occurred in 56.7% of cases, but was not different between groups. There were no recurrences in either group. CONCLUSIONS: Laparoscopic adrenalectomy is a safe and effective treatment for large pheochromocytomas. Intraoperative hemodynamic instability remains a frequent occurrence regardless of tumor size. There were no cases of disease recurrence or iatrogenic pheochromocytosis.


Asunto(s)
Centros Médicos Académicos , Neoplasias de las Glándulas Suprarrenales/cirugía , Adrenalectomía/métodos , Feocromocitoma/cirugía , Neoplasias de las Glándulas Suprarrenales/diagnóstico , Adulto , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Laparoscopía/métodos , Tiempo de Internación , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Oregon/epidemiología , Feocromocitoma/diagnóstico , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
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