Abstract
The bcl-2 gene is the prototype of a newly described family of oncogenes involved in tumorigenesis by blocking apoptosis. The expression of bcl-2 protein was originally described in follicular B-cell lymphomas bearing the 14; 18 translocation. The aim of this paper is to determine the immunohistochemical expression of this gene in cutaneous neoplasms. Formalin- or AMeX-fixed, paraffin-embedded sections were immunostained with monoclonal antibody directed against bcl-2 protein. Normal skin showed positive staining for the majority of keratinocytes in the epidermal basal layer. Bcl-2 positivity was found within the outer root sheath, the clear cells of the eccrine glands, and in some melanocytes at the dermo-epidermal junction. Positivity was also observed within the basal layer cells of seborrheic keratosis and verruca vulgaris. Neoplastic cells in all cases of basal cell epithelioma showed a positive reaction for bcl-2. The squamous cell carcinoma cells were negative in all cases. These results suggest that bcl-2 expression is therefore not directly involved in the malignant transformation, but may be related to epidermal cell differentiation.
