title: Immuno-histochemical expression of p53 protein and iNOS in odontogenic cysts.
abstract: OBJECTIVE
  The present study investigated the expression of p53 protein and iNOS in odontogenic keratocysts (OKCs), dentigerous cysts (DCs) and radicular cysts (RCs) and determined the correlation of these 2 proteins within each cyst type.
  
  
  METHODS
  p53 and iNOS in epithelial lining cells were analyzed in 20 OKCs, 20 DCs and 20 RCs using immuno-histochemistry. The percentage of positive cells was assessed and presented as mean +/-SD. The correlation between the expressions of these 2 proteins in each cyst was carried out using Spearman correlation analysis.
  
  
  RESULTS
  p53 was found in 95% of OKCs, 50% of DCs and 65% of RCs. p53-positive cells in OKCs (12.2 +/- 8.8%) were significantly higher than those in DCs (1.4 +/- 3.2%) and RCs (1.3 +/- 2.4%). iNOS was found in all examined lesions. Statistically, iNOS-positive cells in RCs (86.9 +/- 9.9%) were lower than those in OKCs (94.8 +/- 3.5%) and DCs (96.1 +/- 4.4%). No correlation between the expression of p53 and iNOS was found in each cyst.
  
  
  CONCLUSIONS
  p53 was over expressed in OKCs compared with other lesions. RCs showed the lowest expression of iNOS.
authors.affiliation: Department of Oral Pathology, Faculty of Dentistry, Mahidol University, Bangkok, Thailand. spoomsawat@yahoo.com
authors.forename: Sopee
authors.initials: S
authors.lastname: Poomsawat
authors.forename: Jirapa
authors.initials: J
authors.lastname: Punyasingh
authors.forename: Paisarn
authors.initials: P
authors.lastname: Vejchapipat
mesh_terms: D003803:Dentigerous Cyst / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism*; D009807:Odontogenic Cysts / Q000378:metabolism*; D011842:Radicular Cyst / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
chemical_list: D016159:Tumor Suppressor Protein p53; D052247:Nitric Oxide Synthase Type II