Immunohistochemical expression of Tenascin in embryogenesis, tumorigenesis and inflammatory oral mucosa

Objective: Tenascin is a large extracellular matrix glycoprotein that plays specific role in cell matrix interaction. This protein is mainly attracted because of its oncofetal predominance expression at epithelial-mesenchymal interaction and also been associated with inflammatory response. Thus the aim was to study the expression of Tenascin within the oral cavity in a developing tooth, normal oral mucosa, squamous cell carcinoma and inflammatory mucosa and further to compare its expression in inflammatory mucosa with that of squamous cell carcinoma. Design: A total numbers of 92 cases were included, with 22 being all morphological stages of developing tooth, 10 cases of normal oral mucosa, 30 cases each of inflammatory gingival hyperplasia and oral squamous cell carcinoma. The intensity and pattern of expression was assessed immunohistochemically using anti-human mouse monoclonal Tenascin antibody. Results and conclusion: Tenascin expression in developing tooth was seen mainly at epithelial-mesenchymal junctions, but temporally reduced at cap stage. In normal mucosa TN expression was restricted only at basement membrane zone. Inflammatory gingival hyperplasia intensity of expression was enhanced at the juxtraepithelial stroma and showed reticular pattern of expression. In oral squamous cell carcinoma, intensity of expression was seen in superficial front of the stroma and also around tumour islands with intraepithelial expression and predominantly showed fibrillar pattern of expression. Furthermore, Tenascin expression was noticed around neovascularization. Hence, there is a regulatory system in Tenascin expression and plays a vital role in embryogenesis, tumerogenesis and inflammation in remodelling the stroma for cell migration and also for healing. (C) 2010 Elsevier Ltd. All rights reserved.