title: Claudin-1 expressions decrease in pterygium with respect to normal conjunctiva.
abstract: BACKGROUND
  Pterygium is the fibrovascular growth of the limbal conjunctiva over cornea. This proliferative nature might have a pathogenesis associated with tight junction proteins.
  
  
  OBJECTIVE
  To investigate the tight junction protein claudin-1 expressions in pterygium with respect to normal conjunctiva.
  
  
  METHODS
  This retrospective study included 28 patients who underwent pterygium surgery with autograft. Claudin-1 expressions were immunohistochemically evaluated in normal and lesional conjunctiva of the same eye. Immunohistochemical evaluation was done with regard of both the intensity and the extent of staining. The distribution of the immunohistochemical scores in pterygium and normal conjunctiva has been compared with using McNemar test.
  
  
  RESULTS
  The mean age of the patients was 52.2 ± 11.2 years and male/female ratio was 8/20. Among 28 samples of normal conjunctiva 25 (89.2%) demonstrated a strong immunohistochemical expression with claudin-1 whereas this rate was 10.8% for pterygium samples. Statistical analysis revealed a significant decrease in claudin-1 expressions in pterygium with respect to normal conjunctiva (p < 0.001).
  
  
  CONCLUSIONS
  The loss of claudin-1 appears to be involved in the pathogenesis of pterygium and the future studies will elucidate the exact role of tight junction proteins in the invasive and recurrent nature of pterygium.
authors.affiliation: a Department of Ophthalmology , Ministry of Health and.
authors.forename: Aysun Sanal
authors.initials: AS
authors.lastname: Dogan
authors.affiliation: b Department of Pathology , Ministry of Health, Diskapi Yildirim Beyazit Training and Research Hospital , Ankara , Turkey.
authors.forename: Evrim
authors.initials: E
authors.lastname: Onder
authors.affiliation: b Department of Pathology , Ministry of Health, Diskapi Yildirim Beyazit Training and Research Hospital , Ankara , Turkey.
authors.forename: Ata Turker
authors.initials: AT
authors.lastname: Arikok
authors.affiliation: a Department of Ophthalmology , Ministry of Health and.
authors.forename: Tolga
authors.initials: T
authors.lastname: Bicer
authors.affiliation: a Department of Ophthalmology , Ministry of Health and.
authors.forename: Canan
authors.initials: C
authors.lastname: Gurdal
mesh_terms: D000328:Adult; D062445:Claudin-1 / Q000378:metabolism*; D003228:Conjunctiva / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011625:Pterygium / Q000378:metabolism* / Q000601:surgery
chemical_list: C568108:CLDN1 protein, human; D062445:Claudin-1
keywords: Claudin; conjunctiva; pterygium; tight junction