STUDY OF ODONTOGENIC TUMORS IN THE FACULTY OF DENTISTRY ALEXANDRIA UNIVERSITY AND THE POSSIBLE ROLE OF NESTIN AS A MARKER

Abstract

Introduction: Odontogenic tumors constitute a wide range and diverse kind of lesions derived from the tooth forming apparatus and its remnants. They originate from epithelium, ectomesenchyme or both. Varying degrees of inductive interaction between these embryonic components of the developing tooth germ exist. Nestin is one of the intermediate filaments constituting the cytoskeleton and is known as a marker of neural stem cells or progenitor cells. Human Nestin expression continues during tooth development and disappears when development is complete. Aim of the work: To study the expression of Nestin in different odontogenic tumors, and to highlight the incidence of odontogenic tumors in the Faculty of dentistry, Alexandria University in the past 10 years. Material and Methods: Immunohistochemical analysis was done on 22 surgical specimens of odontogenic tumors and 1 control tissue. Immunohistochemical staining was performed using a Labeled Strept-Avidin Biotin complex method (LSAB). Results: Almost all the ameloblastomas were negative for Nestin while All cases of fibromyxoma, myxoma and odontogenic fibroma showed intense brownish cytoplasmic reaction of Nestin in both the ectomesenchmal cells and the odontogenic epithelial rests. Ameloblastic fibroma and ameloblastic fibro-odontome cases showed immunopositivity of Nestin in the ameloblast like cells and stellate reticulum like cells and in the connective tissue cells but the dentine like tissue showed negative Nestin expression also in odontomes. Conclusion: Nestin protein is expressed in some odontogenic tumours because odontogenic ectomesenchymal tissue is derived from neural crest. Keywords: odontogenic tumors, Nestin, ectomesenchymal tumors, intermediate filaments.