Immunoexpression of integrins in ameloblastoma, adenomatoid odontogenic tumor, and human tooth germs

The expression of integrins alpha 2 beta 1, alpha 3 beta 1, and alpha 5 beta 1 in 30 ameloblastomas (20 solid and 10 unicystic tumors), 12 adenomatoid odontogenic tumors (AOTs), and 5 human tooth germs in different stages of odontogenesis was analyzed. The distribution, location, pattern, and intensity of immunohistochemical expression were evaluated. Intensity was analyzed using scores (0 = absence, 1 = weak staining, and 2 = strong staining). No difference in the immunoexpression of the integrins was observed between solid and unicystic ameloblastomas. When these two ameloblastoma types were pooled into a single group, the following significant differences were found: immunoexpression of integrin alpha 2 beta 1 was stronger in ameloblastomas than in AOTs and tooth germs, and the expression of integrin alpha 5 beta 1 was stronger in ameloblastomas than in AOTs. The lack of detection of integrin alpha 3 beta 1 in tooth germs and its detection in the odontogenic tumors studied suggest that this integrin might be used as a marker of neoplastic transformation in odontogenic tissues.