Besides, most members of histone acetylase (HAT) and histone deacetylase (HDAC) families were reported to be aberrantly expressed in HCC tumor tissues, which were associated with clinical stage, prognosis, and survival rate, and some HDACs inhibitors were taken as candidates for clinical HCC treatment (Li et al., 2011; Quint et al., 2011; Freese et al., 2019; Hu et al., 2019; Inagaki et al., 2016). The gene discussed is HDAC9; the disease is hepatocellular carcinoma.