Furthermore, the IHC staining for GC tissues showed that expression level of SIRT6 was decreased in GC tissues while the expression level of p-STAT3 was increased in GC tissues.
Survival curves generated from Kaplan-Meier plotter suggested that high expression of SIRT1 mRNA was favorable for overall survival in gastric cancer (SIRT1: HR = 0.64, 95% CI = 0.54-0.76, <i>P =</i> 2.2E-07), high expressions of SIRT2-4 and SIRT6-7 were poor for overall survival (SIRT2: HR = 2.31, 95% CI = 1.87-2.87, <i>P =</i> 3.6E-15; SIRT3: HR = 1.99, 95% CI = 1.62-2.45, <i>P =</i> 2.6E-11; SIRT4: HR = 1.41, 95% CI = 1.19-1.68, <i>P =</i> 6.6E-05; SIRT6: HR = 2.02, 95% CI = 1.66-2.47, <i>P =</i> 1.7E-12; SIRT7: HR = 1.96, 95% CI = 1.63-2.35, <i>P =</i> 2.7E-13), whereas no significant association existed between SIRT5 mRNA expression and overall survival.