Participation of hMLH1, p63, and MDM2 proteins in the pathogenesis of syndromic and nonsyndromic keratocystic odontogenic tumors

Abstract

To evaluate the expression of hMLH1, p63, and MDM2 in Gorlin syndrome-associated keratocystic odontogenic tumors (SKOTs) and nonsyndromic keratocystic odontogenic tumors (NSKOTs). Seventeen primary NSKOTs, 17 SKOTs, and 8 recurrent NSKOTs were analyzed by using immunohistochemistry. No significant differences in the hMLH1, p63, or MDM2 labeling indices were observed between groups (P = .398; P = .232; P = .426, respectively). Higher hMLH1 immunoexpression was found in the basal layer of primary NSKOTs. Most KOTs exhibited p63 immunoexpression in the upper layers of the epithelium. MDM2 immunoexpression was observed in the upper epithelial layers of SKOTs and recurrent NSKOTs. It was not possible to correlate the immunoexpression of hMLH1, p63, and MDM2 in SKOTs and primary and recurrent NSKOTs, suggesting that these proteins exert independent effects on the development of these groups of tumors.