Expression of p53, epidermal growth factor receptor, c-erbB2 in oral leukoplakias and oral squamous cell carcinomas

Oral cancer is a leading cause of cancer in India and contributes to 12% deaths worldwide. The identification of high-risk oral premalignant lesions such as leukoplakia and intervention at premalignant stages could result in significant loss of mortality and morbidity among these patients. The most frequently observed genetic aberrations in these lesions are of mutations in p53, c-erbB2, and epidermal growth factor receptor (EGFR). No specific tumor markers have been identified consistently in oral leukoplakias and the available studies show wide variations in their expression.

A total of eighty cases were taken up for study which included forty cases of leukoplakia and forty cases of squamous cell carcinomas (SCCs).

There was a significant correlation between the expression of markers p53 and EGFR in leukoplakia and SCC. The expression of p53 was correlated between leukoplakia, SCC, and control and was found to be significant (P ≤ 0.001). Similarly, EGFR expression was significant (P ≤ 0.001) between cases of leukoplakia, SCCs, and controls. c-erbB2 was found to be negative though cytoplasmic positivity was observed in a few cases. Similarly, in SCCs, it was observed that lesser the differentiation, more is the expression of both p53 and EGFR. Similarly, a definite correlation was observed between p53 and EGFR (P ≤ 0.001) but not with c-erbB2 (P ≤ 1.000).

Thus, the author concludes that p53 and EGFR are useful biomarkers for the diagnosis of leukoplakia and their risk of malignant transformation.