The Expression Pattern and the Prognostic Value of p53, p21, and Bax Proteins in Oral Squamous Cell Cancer

Kim, Sang Hyun; Hwang, Dong Jo; Kim, Jeong Soo; Moon, Jun Hwan; No, Ho Sang

Abstract

BACKGROUND AND OBJECTIVES: The wild-type p53 protein activates different tumor suppressor genes, leading to the Gl arrest following DNA damage. P21 and bax play a pivotal role in the regulation of apoptosis. The authors wanted to find out the relationship among p53, p21 and bax and the correlation between the staining results and dinicopathologic factors. We also assessed their influence on survival in the oral cavity cancer.
MATERIALS AND METHODS
Paraffin embedded tissue sections were made from squamous cell carcinoma of oral cavity from 46 patients. Tissue sections were immunohistochemically stained for the expression of p53, p21 and bax. Results were then compared with the size of primary tumor, lymph node metastasis and histopathalogic diffrentiation. The probability of survival was calculated by the Kaplan-Meier method.
RESULTS
Immunoreactivity of the p53 and p21 were detected dominantly in the nuclei at various levels, and immunoreativity of bax was detected in the cytoplasm, The positive rates of p53, p21, and bax were 54.4%, 58.7%, 26.1%, respectively. The positive rate of p53 and the negative rate of bax expression were significantly increased with T-stage but were not affected by N-stage and histopathologic differentiation. P21 had no correlation with the T-stage, N-stage nor with pathologic differentiation. In the multivariate analysis, neither the single oncoprotein nor the combinations of p53, p21, bax had influence on survival statistically.
CONCLUSION
The bax protein and mutant p53 protein can be a biological marker for primary tumor progression.