title: COX-2 mRNA expression is significantly increased in acid-exposed compared to nonexposed squamous epithelium in gastroesophageal reflux disease.
abstract: BACKGROUND
  Little is known about the role of cyclooxygenase (COX)-2 in gastroesophageal reflux disease (GERD) and the development of Barrett's metaplasia. The objectives of this study were to further analyze COX-2 mRNA expression in patients with GERD compared to Barrett's esophagus (BE) and Barrett's cancer (BC).
  
  
  METHODS
  Tissue samples from 110 patients with GERD (n = 43), BE (n = 20), and BC (n = 47) were obtained in routine upper GI endoscopy. Expression levels of COX-2 were measured by quantitative real-time reverse trancriptase polymerase chain reaction (RT-PCR). Also, 24-h pH monitoring was performed in all patients of the GERD study group and the DeMeester composite score was used to match COX-2 mRNA expression with the severity of acid exposure in the lower esophagus.
  
  
  RESULTS
  COX-2 mRNA is progressively upregulated within the metaplasia-dysplasia-adenocarcinoma (MDA) sequence (p = 0.001). COX-2 levels of the squamous epithelium in the distal esophagus from patients with GERD and a pathologic mean DeMeester score (>14.72) were significantly higher than in patients with normal DeMeester scores (p = 0.01).
  
  
  CONCLUSIONS
  In summary our findings suggest that alterations in COX-2 mRNA expression occur independently of endoscopic or histologic signs of GERD in the acid-exposed squamous epithelium of the distal esophagus. However, this early COX-2 increase in GERD is further upregulated within the MDA sequence for yet unknown reasons.
authors.affiliation: Department of Visceral and Vascular Surgery, University of Cologne, Cologne, Germany.
authors.forename: Georg
authors.initials: G
authors.lastname: Lurje
authors.forename: Daniel
authors.initials: D
authors.lastname: Vallbohmer
authors.forename: Peter H
authors.initials: PH
authors.lastname: Collet
authors.forename: Huan
authors.initials: H
authors.lastname: Xi
authors.forename: Stephan E
authors.initials: SE
authors.lastname: Baldus
authors.forename: Jan
authors.initials: J
authors.lastname: Brabender
authors.forename: Ralf
authors.initials: R
authors.lastname: Metzger
authors.forename: Michaela
authors.initials: M
authors.lastname: Heitmann
authors.forename: Susanne
authors.initials: S
authors.lastname: Neiss
authors.forename: Ute
authors.initials: U
authors.lastname: Drebber
authors.forename: Arnulf H
authors.initials: AH
authors.lastname: Holscher
authors.forename: Paul M
authors.initials: PM
authors.lastname: Schneider
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001471:Barrett Esophagus / Q000378:metabolism*; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D018450:Disease Progression; D004848:Epithelium / Q000473:pathology; D004938:Esophageal Neoplasms / Q000378:metabolism*; D005260:Female; D005764:Gastroesophageal Reflux / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000378:metabolism; D015854:Up-Regulation / Q000502:physiology
chemical_list: D012333:RNA, Messenger; D051546:Cyclooxygenase 2