Expression of P53 Protein and Ki-67 Antigen in Oral Leukoplakia with Different Histopathological Grades of Epithelial Dysplasia

AIMS AND OBJECTIVE: The aim of this study is to investigate the expression of p53 protein and Ki-67 antigen in normal oral mucosa and oral leukoplakia with different grades of dysplasia using immunohistochemistry and to clarify the correlation of the expression of these cell cycle regulatory proteins. MATERIALS AND METHODS: A total of 20 archival tissue blocks obtained from our department which were diagnosed as mild (n = 5), moderate (n = 5), and severe dysplasia (n = 5) with normal mucosa (n = 5) as a control. Positivity of Ki-67 and p53 was analyzed using Statistical Package for the Social Sciences (IBM Corp. Released 2013. IBM SPSS Statistics for Windows, Version 22.0 Armonk, NY:IBM Corp) software. RESULTS: All samples showed positive staining for p53 and Ki-67. Statistically significant difference (P < 0.05) was seen between the frequency of occurrence of p53 and Ki-67 pattern of expression among all the groups. The intensity of staining was mild to intense in basal layer as there was a progression toward the severity of the disease. Almost 81.1% correlation existed between p53 and Ki-67 with high correlation and marked relationship. CONCLUSION: Oral leukoplakia represents the most common oral potentially malignant disorder (OPMD). Molecular biological markers such as p53 and Ki-67 are considered to be of great value in the diagnosis and prognostic evaluation of OPMD. Our results emphasize the potential use of p53 protein and Ki-67 antigen as significant molecular markers for early detection of PMDs and its risk of developing oral squamous cell carcinoma.