title: Expression of Fas/FasL in patients with oral lichen planus.
abstract: OBJECTIVE
  To investigate the malignant potential of oral lichen planus (OLP) on the basis of expression of the Fas/FasL markers in healthy individuals (H), OLP patients and patients with squamous cell carcinoma (SCC).
  
  
  METHODS
  40 patients with OLP and two control groups were included in this research (H and patients with SCC). Immunohistochemistry for Fas and FasL was carried out using an avidin-biotin peroxidase complex method.
  
  
  RESULTS
  Only a low percentage of infiltrating lymphocytes and no keratinocytes were Fas-positive in OLP specimens. The highest percentage of Fas-staining keratinocytes in our survey was identified mostly in H and patients with well-differentiated SCC. In most cases of SCC, OLP and H a high percentage of keratinocytes and lymphocytes were FasL-positive. FasL expression was negatively correlated with the degree of cell differentiation and apoptosis. Taking into consideration that all carcinomas in this survey were highly differentiated, it is not surprising that no statistically significant differences in FasL expression between H, OLP and SCC specimens were detected.
  
  
  CONCLUSIONS
  Downregulation of Fas expression in keratinocytes and lymphocytes of OLP specimens, together with upregulation of FasL, may serve as initial prognostic biomarker in oral cancer development.
authors.affiliation: Clinic of Periodontology and Oral Medicine, Faculty of Dentistry, University of Belgrade, Belgrade, Serbia. hadzi04@yahoo.com
authors.forename: M
authors.initials: M
authors.lastname: Hadzi-Mihailovic
authors.forename: H
authors.initials: H
authors.lastname: Raybaud
authors.forename: R
authors.initials: R
authors.lastname: Monteil
authors.forename: L
authors.initials: L
authors.lastname: Jankovic
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism*; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000473:pathology; D015536:Down-Regulation; D053222:Fas Ligand Protein / Q000378:metabolism*; D006801:Humans; D015603:Keratinocytes / Q000378:metabolism / Q000473:pathology; D017676:Lichen Planus, Oral / Q000378:metabolism* / Q000473:pathology; D016246:Lymphocytes, Tumor-Infiltrating / Q000378:metabolism; D009062:Mouth Neoplasms / Q000378:metabolism* / Q000473:pathology; D011230:Precancerous Conditions / Q000378:metabolism* / Q000473:pathology; D019014:fas Receptor / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; C505661:FASLG protein, human; D053222:Fas Ligand Protein; D019014:fas Receptor