SIRT7 and hepatocellular carcinoma: Elevated expression of SIRT7 is frequently observed in many cancer types including epithelial prostate carcinomas (Malik et al., 2015), hepatocellular carcinoma (Zhao et al., 2019), colorectal cancer (Yu et al., 2014), and lung cancer (Cheng et al., 2019), and high SIRT7 levels are associated with poor prognosis.