IMMUNOHISTOCHEMICAL EVALUATION OF bcl-2 ONCOPROTEIN IN ORAL DYSPLASIA AND CARCINOMA.

The proto-oncogene bcl-2 is associated with follicular lymphoma involving translocation t (14; 18) (q32; q21) and is also over expressed in various neoplasms. Investigations into the sequential over expression of this oncoprotein in precancerous and cancerous lesions of the oral mucosa are lacking, and the possible role of bcl-2 in oral tumour progression remains unknown. Objectives: Objectives of the study were to evaluate the expression of bcl-2 oncoprotein in severe epithelial dysplasia and different grades of Oral squamous cell carcinoma. Methods : Immunohistochemical analysis were carried out in 10 cases of severe epithelial dysplasia & 10 cases each of well differentiated, moderately differentiated and poorly differentiated oral squamous cell carcinomas. Results & Conclusion: - Over expression of this oncoprotein was seen in severe epithelial dysplasia involving entire thickness of the epithelium with its down regulation in differentiating carcinomas, suggesting the role of this oncoprotein in early stages of tumour progression. [ABSTRACT FROM AUTHOR]