Subgroup analyses by cancer types suggested that there was obviously significant association between SIRT3 expression and OS in gastric cancer (HR = 0.62, 95% CI = 0.43–0.89, P = 0.009) and hepatocellular carcinoma (HR = 0.56, 95% CI = 0.42–0.74, P<0.0001) patients, which indicated patients with higher SIRT3 expression have longer overall survival (Fig 2B). This evidence concerns the gene SIRT3 and cancer.