Immunohistochemical Findings of p53, PCNA, and bcl-2 in the Tumor and Epidermis Overlying and Adjacent to Non-melanoma Skin Cancers / 대한피부과학회지

ABSTRACT

BACKGROUND: In both normal tissue development and malignant cell growth, the maintenance of cell numbers reflects a balance between cell proliferation and cell death. Excessive growth may result from uncontrolled cellular proliferation or limited cell death. The growth process of squa mous cell carcinorna(SCC) has recently been reported to differ from that of basal cell carcinoma (BCC). Several reports have suggested that the normal-appearing, overlying epidermis might be a proliferative and be a precursor lesion of BCC. SCCs occur in burn scars, chronic ulcers, and chronic sinus but the najority of SCCs are actinic in origin. It is possible to develop subsequent. skin cancer from the normal-appearing epidermis adjacent to SCC due to chronic sun-exposure. OBJECTIVE: The purpose of this study was to investigate growth dynamics of non-melanorna skin cancers and characteristics, including the carcinogenic property, of the normal appearing epidermis overlying and acljacent to non rnelanoma skin cancers. METHODS: We compared expressions for p53, PCNA, bcl 2, and TGF-alpha in 21 BCCs and 8 SCCs by irnmunohistochi.mical staining with a labelled strept,avidin biotin complex(LSAB) method. RESULTS: The results were as follows. 1) Expressions for p53 and PCNA within the tumor remarkably increased and the distribution pattern of expression for p53 was not always consistent with that for PCNA. 2) An expression the bcl-2 was increased in half of the BCCs, but not in all of the SCCs. 3) The epidermis overlying the BCC showed increased expressions for p53, PCNA, and TGF-alpha. 4) The epidermis adjacent to the SCC showed increased expressions for p53, and PCNA in a few of cases. CONCLUSION: We suggest that a neoplastic transformatiqn in BCC is caused by extended cell survival rather than increased cell proliferation, but in SCC it is caused by other mechanisms, and that the proliferativ activity in the epiderrnis overlying BCC is different from the normal epidermis and maybe repr'sents carcinogenic activity of the epidermis.