Immunohistochemical expression of E-cadherin and β-catenin in ameloblastomas and tooth germs

Objective. The aim was to analyze the expression of E-cadherin and beta-catenin in ameloblastomas and tooth germs to determine their roles in cell differentiation processes and invasiveness compared with odontogenesis. Study design. Twenty-one ameloblastoma cases (16 solid and 5 unicystic tumors) and 5 tooth germs were submitted to the immunohistochemical detection of E-cadherin and beta-catenin. Immunoreactivity was evaluated using descriptive and semiquantitative analysis, investigating the location and intensity of staining. The Fisher exact test was performed, and P values of <.05 were considered to indicate statistical significance. Results. There was no statistically significant difference in the expression of E-cadherin and beta-catenin between solid and unicystic ameloblastomas (P = .59; P = .63; respectively). The same was found when comparing solid and unicystic ameloblastomas with the tooth germs for both E-cadherin (P = .53; P = .44; respectively) and beta-catenin (P = .12; P = .16; respectively). Nuclear staining of beta-catenin was observed in only 4 cases (3 solid and 1 unicystic tumor). Conclusion. The results showed no differences in the expression of E-cadherin or beta-catenin between tooth germs and solid and unicystic ameloblastomas. The expression of these molecules seems mainly to be related to the process of cell differentiation. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010; 109: 425-431)