title: Expression of claudin-4 and beta-catenin in gastric premalignant lesions.
abstract: OBJECTIVE
  Abnormal expression of claudin-4 and beta-catenin play a role in carcinogenesis. The purpose of the present study was to examine claudin-4 and beta-catenin expression in normal and precancerous gastric mucosa.
  
  
  METHODS
  Endoscopic biopsy specimens [normal gastric mucosa (n = 22), intestinal metaplasia (n = 24), dysplasia (n = 18), Helicobacter pylori (H. pylori)-associated chronic gastritis (n = 32) and remnant gastric mucosa (n = 18)] obtained from different 114 patients were examined by immunohistochemistry.
  
  
  RESULTS
  Claudin-4 expression was present in 94.4% of dysplasia, 87.5% of intestinal metaplasia, 62.5% H. pylori-associated chronic gastritis, and 88.9% remnant gastric mucosa but only 18.2% of normal gastric mucosa biopsies. Decreased expression of beta-catenin was present in 27.8% of dysplasia, 8.3% of intestinal metaplasia, 15.6% of H. pylori-associated chronic gastritis, and 22.2% of remnant gastric mucosa biopsies, but was not present in normal gastric mucosa. When compared with normal gastric mucosa, there was a significant difference in claudin-4 expression in all groups (P < 0.05), but a significant difference was detected in dysplasia and remnant gastric mucosa for beta-catenin (P < 0.05).
  
  
  CONCLUSIONS
  Our results suggest that claudin-4 expression is upregulated in premalignant gastric alterations.
authors.affiliation: Inonu University Medical Faculty, Department of Gastroenterology, Malatya, Turkey. yuksel_seckin@hotmail.com
authors.forename: Y
authors.initials: Y
authors.lastname: Seckin
authors.forename: S
authors.initials: S
authors.lastname: Arici
authors.forename: M
authors.initials: M
authors.lastname: Harputluoglu
authors.forename: O
authors.initials: O
authors.lastname: Yonem
authors.forename: A
authors.initials: A
authors.lastname: Yilmaz
authors.forename: H
authors.initials: H
authors.lastname: Ozer
authors.forename: M
authors.initials: M
authors.lastname: Karincaoglu
authors.forename: U
authors.initials: U
authors.lastname: Demirel
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease; D062506:Claudin-4; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism; D005756:Gastritis / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D008875:Middle Aged; D011230:Precancerous Conditions / Q000378:metabolism*; D013274:Stomach Neoplasms / Q000378:metabolism*; D015854:Up-Regulation / Q000502:physiology; D051176:beta Catenin / Q000378:metabolism*
chemical_list: C568157:CLDN4 protein, human; D062506:Claudin-4; D008565:Membrane Proteins; D051176:beta Catenin