Immuno-histochemical expression of p53 protein and iNOS in odontogenic cysts.

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. MATERIAL AND METHOD 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. CONCLUSION p53 was over expressed in OKCs compared with other lesions. RCs showed the lowest expression of iNOS.