EXPRESSION OF TENASCIN IN ODONTOGENIC-TUMORS

We investigated the expression of tenascin in a series of odontogenic tumours (n = 63) of epithelial and epithelial-ectomesenchymal origin b y using immunohistochemical methods. A heterogeneity of expression of tenascin was observed in odontogenic tumours. The heterogeneity was mo st prominent in odontogenic tumours not forming calcified tissues. In these ameloblastomas and adenomatoid odontogenic tumours, tenascin was mainly localised at the epithelial tumour cell-mesenchymal tissue int erface. In the calcifying epithelial odontogenic tumour, ameloblastic fibroma and odontoma, a widespread stromal immunoreactivity was observ ed which was, however, unreactive in the calcified masses. The stellat e reticulum-like cells and granular cells of ameloblastoma also showed a positive immunoreactivity for tenascin. The results of the present study suggest that expression of tenascin in the stromal tissue of odo ntogenic tumours differs according to the potential of forming calcifi ed masses by the tumour cells irrespective of tumour cell morphology.