Expression of the Peroxisome-proliferator-activated Receptor-gamma in Human Gastric Cancer

ABSTRACT

PURPOSE: Recently, interest in peroxisome-proliferator-activated receptors (PPAR) has increased, although clinical studies of the effect of PPAR-gamma expression on gastric cancer have not been reported yet. In this study, we investigated the role of PPAR-gamma expression in gastric cancer patients. MATERIALS AND METHODS: One hundred twenty-eight (128) samples of both gastric cancer and normal tissues were obtained from 128 patients who had undergone at a curative gastrectomy at Seoul Medical Center from Jan. 2001 to Dec. 2005. PPAR-gamma expression was determined by using immunohistochemical staining, and the results were analyzed. The statistical analysis was based on clinicopathological findings and the differences in survival rates. RESULTS: The mean age of the patients was 61, and the malefemale ratio was 1.91. PPAR-gamma expression was significantly higher in cancer tissues than in normal tissue (81.3% vs. 57.0%, P<0.001). There was insignificant difference between well and moderately differentiated types and poorly differentiated types in terms of the expression of PPAR-gamma (87.0% vs. 74.6%, P=0.074). In the univariate analysis the survival rate was significantly increased when PPAR-gamma was expressed in normal tissue (P=0.003). In the multivariate analysis, only the UICC TNM staging had significance related to the survival rate. CONCLUSION: The rate of PPAR-gamma expression was higher in cancer tissue than it was in normal tissue from gastric cancer patients. In the univariate analysis, PPAR-gamma expression in normal tissue had significance with respect to survival, but the multivariate analysis showed no such significance. Thus, we should further evaluate more cases to determine whether or not such a significance exists.