Down-regulated expressions of PPARγ and its coactivator PGC-1 are related to gastric carcinogenesis and Lauren's classification in gastric carcinoma

摘要

Objective:To explore the relationship between peroxisome proliferator activated receptor-gamma(PPARγ)and peroxisome proliferator-activated receptor-gamma coactivator-1(PGC-1)expression in gastric carcinoma(GC),and analyze their correlations with clinicopathological features and clinical outcomes of patients.Methods:The two-step immunohistochemical method was used to detect the expression of PPARγand PGC-1in 179 cases of GC,and 108 cases of matched normal gastric mucosa.Besides,16 cases of fresh GC specimens and corresponding normal gastric mucosa were detected for PGC-1 expression with Western blotting.Results:The positive rates of PPARγand PGC-1 expression were significantly lower in GC(54.75%,49.16%)than in normal gastric mucosa(70.37%,71.30%),respectively(P<0.05).The decreased expression of PGC-1 in GC was confirmed in our Western blot analysis(P=0.004).PPARγand PGC-1 expressions were related to Lauren’s types of GC(P<0.05).Positive correlation was found between PPARγand PGC-1 expression in GC(rk=0.422,P<0.001).The survival time of PPARγnegative and positive patients was 36.6±3.0 vs.38.5±2.7 months,and no statistical difference was found between the 5-year survival rates of two groups(34.4%vs.44.1%,P=0.522,log-rank test);the survival time of PGC-1 negative and positive patients was36.2±2.8 vs.39.9±2.9 months,while no statistical difference was found between the 5-year survival rates of the two groups(32.0%vs.48.2%,P=0.462,log-rank test)Conclusions:Decreased expression of PPARγand PGC-1 in GC was related to the Lauren’s classification.Their expressions in GC were positively correlated,indicating that their functions in gastric carcinogenesis may be closely related.