Immunohistopathological Study of c-FLIP Protein in Mycosis Fungoides

Background: Mycosis fungoides (MF) is the commonest variant of primary cutaneous T cell lymphoma with several clinicopathologic variants. Defective apoptotic mechanism may be important in the pathogenesis and progression of MF. c-FLIP protein is an important anti-apoptotic marker and chemotherapeutic resistant factor. This study aimed to evaluate the c-FLIP expression in MF and its role in the pathogenesis of MF. Methods: Twenty patients of MF and ten normal persons were included in this study. Skin biopsies were obtained from both patients and controls. They were studied and examined immunohistochemically for the expression of CD4 and c-FLIP. Results: c-FLIP expression was significantly increased in patients when compared to controls in both epidermis and dermis. There were positive correlations between c-FLIP expression and CD4+ expression in both epidermal and dermal lesions of patients group. There were statistically significant positive correlations between c-FLIP expression (in both dermal and epidermal lesions) and the age of patients. c-FLIP expression increased with the tumor progression but with no statistical significance. Conclusion: Defective regulation of apoptosis has been considered as a main cause for accumulation of clonal T cells, and it was related to an increased expression of c-FLIP which may have a role in the pathogenesis of MF. Also, c-FLIP may have prognostic information in MF as its level increased with both age of the patients and tumor progression.