Expression of Proliferatin Cell Nuclear Antigen ( PCNA ) and P53 Protein in Skin Carcinomas

ABSTRACT

Basal cell carcinoma(BCC) and squamous cell carcinoma(SCC) are the most frequent neoplasms of the human skin. Ultraviolet radiation in sunlight is a well established mutagen of p53 gene and is the major epidemiological risk factor in the development of basal cell carcinoma and squamous cell carcinoma. There is no general agreement in the several studies about the percentage of p53 positive staining of BCCs and SCCs. To evaluate the relationship between p53 positivity, PCNA index and other clinicopathological parameters, immunohistochemistry for p53 protein and PCNA was performed in 20 cases of BCCs, 14 SCCs and 3 Bowen's disease. The results are as follows; 1) The immunostaining of p53 protein and PCNA is localized to the nuclei of the tumor cells and some of adjacent normal surface squamous epithelium, more intense in the periphery of the tumor nests. 2) The pattern of immunostaining of PCNA is similar to that of p53 protein. 3) There was no difference in the expression of p53 protein according to the location of tumors, age or sex of patients, except thickness. 4) There was no difference among the BCCs, SCCs and Bowen's disease in the percentage of positive staining of p53 protein and PCNA but the aggressive BCCs and the less differentiated SCCs showed more high PCNA index and more intense p53 immunostaining. Above results suggest that the expressions of p53 protein and PCNA are related to the differentiation and biological behavior such as infiltrating property of the tumor, and they may be used as adjuvant indicators of prognosis in the skin carcinomas.