Prognostic significance of p53 expression in various grades of epithelial dysplasia

Abstract

Background: Potentially malignant disorders in oral mucosa represent the morphological steps of epithelial transformation in the form of various grades of dysplasia. Only few cases of dysplasia evolve into carcinoma, and there is no specific markers invented which can predict the probability of progression. Oral carcinogenesis is a multistage course which constitutes a sequence of molecular events resulting in cell cycle dysregulation. p53 is the most commonly affected tumor suppressor gene. p53 mutation leads to uncontrolled proliferation of cancer cells as well as increased p53 protein. p53 overexpression has been suggested to be consistent indicator for the development of oral cancer. The objective of this study is to investigate p53 immunohistochemical expression in various grades of oral epithelial dysplasia (ED) and to estimate the correlations between their expression levels in various grades of dysplasia. Materials and Methods: This study is done at the Department of Oral Pathology and Microbiology, SPDC, Wardha. Total four groups were taken. Ten patients each of mild, moderate, and severe ED, i.e., total-30 patients and 10 control patients. The sample size required for the group was calculated by using the required formula. p53-positive cells were counted in 5 high power field (HPF) in all grades of ED and labeling index was measured. Results: Analysis of variance test was applied to see the differences in the p53 expression.It was found that-LI increases with the increasing grades of EDP53 expression observed in 5 HPF in all grades of ED yields this expression only in basal cell layer in normal oral mucosa, basal and parabasal cell layers in mild ED and basal, parabasal and suprabasal layers in moderate and severe grades of ED in focal areas.Conclusion: The increase in the p53 expression in epithelium correlates to various grades of EDs.