[P53 expression and clinical significance in oral squamous cell carcinoma]

P53 protein expression was investigated in oral squamous cell carcinomas and oral premalignant lesions by monoclonal antibody Do-1 and immunohistochemistry technique. 4 of 12 (33.3%) samples of severe epithelial dysplasia and 25 of 44 (56.8%) samples of squamous cell carcinoma expressed P53 protein while all the normal mucosa, mild and moderate epithelial dysplasia were negative. The P53 expression in carcinomas was associated with differentiation, lymph node metastasis and tumour stage. This result indicated that P53 genic mutation might be an early event in oral mucosa carcinogenesis and related to oral tumor progression. Detection of P53 protein probably has clinical significance in identifying the premalignant lesions of oral mucosa and predicting the prognosis of oral carcinomas.