title: Factors regulating nuclear factor-kappa B activation in esophageal cancer cells: Role of bile acids and acid.
abstract: OBJECTIVE
  Gastroesophageal reflux disease is considered to be a major risk in the development of esophageal adenocarcinoma. Nuclear factor-kappa B (NF-κB) plays important roles in the regulation of several genes coding for cytokines, cell proliferation, and apoptosis. To understand the role of bile and acid in the causation of esophageal cancer, we have examined the effects of bile acids and acid on NF-κB activation in the esophageal epithelial cells OE33 and SKGT-4 qualitatively and quantitatively.
  
  
  METHODS
  Analysis of NF-κB activation in esophageal epithelial cells in response to bile acids and acid was performed by electrophoretic mobility shift assay, Western blotting and the translocation NF-κB was assessed by high content analysis (HCA). Cyclooxygenase-2 (COX-2) promoter activity was assessed by transient transfection assays.
  
  
  RESULTS
  This study demonstrated that bile acids and acid activated NF-κB in a dose- and time-dependent manner. HCA analysis was an invaluable method in quantifying NF-κB translocation at the single cell population level following bile or acid treatment. Furthermore, deoxycholic acid (DCA) and acid-induced COX-2 promoter activity, and a mutation in the NF-κB and activator protein-1 (AP-1) binding sites remarkably reduced the reporter gene activity induced by DCA or acid.
  
  
  CONCLUSIONS
  Our data demonstrate that bile and acid induce NF-κB activation in esophageal cells qualitatively and quantitatively. The induction of COX-2 promoter activity by DCA and acid was mediated via NF-κB and AP-1 transcription. The activation of NF-κB signaling pathway in esophageal cells may contribute to the development of esophageal cancer, and, therefore, modulating of NF-κB pathway may uncover new therapeutic strategies.
authors.forename: Mohamed Mahmoud M
authors.initials: MM
authors.lastname: Abdel-Latif
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Inoue
authors.forename: Dermot
authors.initials: D
authors.lastname: Kelleher
authors.affiliation: Department of Surgery, Trinity Centre for Health Sciences, St. James's Hospital, Dublin 8, Ireland.
authors.forename: John V
authors.initials: JV
authors.lastname: Reynolds
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D017209:Apoptosis / Q000187:drug effects; D001647:Bile Acids and Salts / Q000008:administration & dosage; D001665:Binding Sites / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D051546:Cyclooxygenase 2 / Q000096:biosynthesis / Q000235:genetics*; D003840:Deoxycholic Acid / Q000008:administration & dosage; D004938:Esophageal Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D016328:NF-kappa B / Q000096:biosynthesis / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000187:drug effects; D018808:Transcription Factor AP-1 / Q000096:biosynthesis / Q000235:genetics*; D015533:Transcriptional Activation / Q000187:drug effects
chemical_list: D001647:Bile Acids and Salts; D016328:NF-kappa B; D018808:Transcription Factor AP-1; D003840:Deoxycholic Acid; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human