AN IMMUNOHISTOCHEMICAL STUDY ON THE EXPRESS1ON OF TGF-beta IN THE AMELOBLASTOMA AND DEVELOPING TOOTH GERM OF HUMAN EMBRYO AND FETUSES

ABSTRACT

Dysregulation of TGF-beta that is a modulator of cell growth and differentiation can result in uncontrolled growth and tumor formation. Monitoring these pattern of genes and protein expression during tumor development will provide a basis for understanding normal growth and distortion of osteochondrogenesis. Our comparative studies on the experssion of TGF-beta protein indicate that TGF-beta may primarily be a regulator of epithelial differentiation during tooth development (between 4 weeks and 40 gestational weeks) and tumorigenesis of odontogenic neoplasm (ameloblastoma). In early human tooth germ (cap/early bell stage) TGF-beta protein was found in the epithelial dentallamina and enamel orgen. TGF-beta experessions were seen in inner and outer dental epithelium during bell stage. During enamel and cementum appositional stage, TGF-beta expression shifted from the ameloblast to the odontoblast. In eruption stage, TGF-beta expressions look like moderate positive pattern in odontoblast and rare pattern in enamel, dentin and cementum. TGF-beta expressions of follicular and plexiform amelobalstoma are moderate positive reaction in ectodermal tumor components and mild positive in vessels of stroma tissue. In acanthomatous type, TGF-beta expression was shown severely positive finding in stellate reticulum cell. TGF-beta expressions were noted moderate reaction in margin of tumor epithelium and stellate reticulum cell of granular ameloblastoma. In unicystic ameloblastoma, TGF-beta expression was rare feature in cystic luminal epithelium. With these result, I should be suggested that TGF-beta may play an important role in epithelial-mesenchymal interactions in human tooth morphogenesis and development of odontogenic epithelial tumors.