Immunohistochemical analysis of MMP-13 and EMMPRIN in epithelial odontogenic lesions

Purpose To investigate the contribution of MMP-13 in tumor aggressiveness, by acting on the reorganization of the extracellular matrix, regulating the biological activity of cytokines in odontogenic epithelial lesions, as well as to evaluate the role of EMMPRIN as an inducer of MMP-13. Methods Twenty solid ameloblastomas (SAs), 10 unicystic ameloblastomas (UAs), 20 odontogenic keratocysts (OKCs), and 20 adenomatoid odontogenic tumors (OATs) were selected. The expression of MMP-13 and EMMPRIN was evaluated in epithelial/connective tissue by determining the score of immunoreactive cells. Results Higher concentration of MMP-13 was observed in epithelium of SAs and OKCs (p = 0.316), while in connective, MMP-13 was more expressed in OKCs and UAs (p = 0.213). OKCs exhibited the highest immunoreactivity score for EMMPRIN in the epithelium (p = 0.091). In connective tissue, a larger number of immunoreactive cells were observed in OKCs and UACs (p = 0.357). There was a moderate correlation (r = 0.343/p = 0.004) between MMP-13/EMMPRIN in epithelium and strong correlation (r = 0.474/p < 0.001) in connective tissue. Conclusion We suggest that the OKCs, SAs and UAs presented greater immunoexpression for MMP-13 and EMMPRIN, since they were lesions of more aggressive behavior, with smaller expressions in the AOTs that are admittedly indolent. However, we did not find a statistically significant difference between the expression of MMP-13 and EMMPRIN in lesions studied. The positive correlation found between MMP-13 and EMMPRIN in the epithelial and connective tissue of odontogenic lesions analyzed, seems to be related to the role of EMMPRIN as an inducer of MMP-13 expression.