Prognostic significance of hMSH2, hMSH3, and hMSH6 expression in ameloblastoma.

ABSTRACT

OBJECTIVE: The aim of this study was to investigate hMutS proteins in developing human tooth, ameloblastomas, and ameloblastic carcinoma and to determine whether the expression of these proteins has any prognostic potential. STUDY DESIGN: Ten cases of developing human tooth, 39 ameloblastomas, and 2 ameloblastic carcinomas were used to determine the distribution of the proteins during the process of carcinogenesis. Simultaneously, another sample of 73 ameloblastomas was arranged in tissue microarray, and their clinical, microscopic, and radiographic features; treatment outcome; presence of BRAF-V600E mutation; and follow-up data were assessed to determine the prognostic relevance of the expression of hMutS (hMSH2, hMSH3, hMSH6) and Ki-67. hMSH2 and hMSH6 were significantly downexpressed in ameloblastomas (P = .0059) compared with developing human tooth (P < .0001). RESULTS: hMSH2, hMSH3 expression were significantly associated with BRAF-V600E mutation (P < .05). Simultaneous overexpression of hMutS was associated with recurrence (P = .035); however, these did not predict the disease-free survival of patients (P > .05). CONCLUSIONS: hMutS proteins are downregulated in ameloblastoma; moreover, simultaneous overexpression of these proteins in ameloblastoma was associated with recurrence but did not predict disease-free survival.