PP117: Does podoplanin contribute to the cytoskeletal remodelling activity in ameloblastomas?

Purpose To investigate the relationship between podoplanin expression and cytoskeletal remodeling activity of the odontogenic epithelium of ameloblastomas. Material and methods Nineteen paraffin-embedded ameloblastomas were immunohistochemically analyzed using anti-human podoplanin and anti-human ezrin antibodies. The membranous and cytoplasmic expression of both antibodies in the neoplastic odontogenic epithelial cells was evaluated using a scoring method. The correlation between the immunostaining of ezrin and podoplanin in ameloblastomas was verified through the Spearman’s correlation test and membranous expression was compared with cytoplasmic expression of both antibodies through Wilcoxon test. The level of significance was set at 5% for all tests. Results All ameloblastomas displayed podoplanin and ezrin expression in ameloblast-like cells of the epithelial islands and cords. The majority (94.7%) of the neoplasias presented high expression of ezrin. Cytoplasmic expression of ezrin was statistically stronger than membranous staining of this protein in the tumors ( p = 0.025). Membranous expression of podoplanin was inversely correlated with membranous ezrin expression ( r = −0.66; p = 0.002). Conclusion These results suggest a synergistic role of cytoplasmic ezrin and membranous podoplanin expressions in the local invasion process of ameloblastomas.