[Expression of Fas, FasL and IFN-gamma in gastric cancer].

OBJECTIVE:To study the expression of Fas, Fas ligand (FasL) and IFN-gamma in gastric cancer and its possible significance. METHODS:Fifty-eight gastric paraffin wax embedded cancer tissues and fifty-three normal tissues adjacent gastric cancer were tested for the expression of Fas and FasL protein by immunohistochemistry and IFN-gamma mRNA by in situ hubridisation respectively. RESULTS:The positive rate of Fas in cancer cells of gastric cancer tissues was significantly lower than that in gastric epithelial cells of the tissues adjacent cancer(19.0% and 64.2%, respectively; chi 2 = 23.46, P = 0.00). The positive rate of FasL in cancer cells of gastric cancer tissues was significantly higher than that in gastric epithelial cells of the tissues adjacent cancer(63.8% and 45.3%, respectively; chi 2 = 3.83, P = 0.05). The positive rate of IFN-gamma in cancer cells of gastric cancer tissues was significantly lower than that in gastric epithelial cells of the tissues adjacent cancer(0.0% and 49.1%, respectively; chi 2 = 37.16, P = 0.00). CONCLUSION:The Fas-FasL system was unbalanced, and the expression of IFN-gamma was low in gastric cancer cells in this study. These may be related to the carcinogenesis of gastric epithelial cells and might be responsible for the immune escape of these cells.