Objective: To investigate the features of Fas-associated death domain (FADD) expression in HCC and to determine its relationship with hepatic apoptosis.
Methods: Immunohistochemistry method was used to detect FADD expression in HCC. In situ end-labeling (ISEL) was employed to determine apoptotic cells.
Results: Ten cases (25. 6%) of HCC were detected to express FADD protein. The positive rate in HCC was lower than that in non-cancerous adjacent liver tissues which showed as high as 62.5% cases harbored FADD protein (P<0.05). Six out of 18 (33.3%) cases of mid to well differentiated HCC had detectable FADD protein. It is a little higher, but with no statistic significance, than that in poorly differentiated HCC which showed only 19% cases were positive for FADD. In those of grade I/II, 8 cases (38.1%) were FADD positive, while only 11.1% (2/18) cases of grade III/IV had FADD protein (P<0.05). No relationship was found between FADD expression and other clinical features, such as sex, age, tumor size or metastasis. ISEL positive cells could be seen in all cases of HCC. The hepatic apoptosis was associated with FADD expression because more apoptotic cells were detected in those cases which showed moderate to strong FADD positive, as compared with negative or weak FADD positive cases (P<0.05). While no relationship was found between FADD expression and hepatic apoptosis in non-cancerous adjacent liver tissues.
Conclusion: Loss of FADD expression plays an important role in HCC carcinogenesis. The apoptosis of cells is associated with FADD expression in HCC.