SIRT1 and hepatocellular carcinoma: The combined analysis of 8 studies showed that high expression of SIRT1 was associated with poor prognosis in OS in HCC patients (hazard Ratio (HR)=1.82, 95% confidence interval (CI): 1.49-2.22, P<0.00001) without significant heterogeneity (I2 =12%, P=0.34) (Figure 2).