HDAC1 and central nervous system cancer: Given that low pathological grade, IDH1 mutant, and 1p/19q codeletion were favorable prognostic factors, the fact that HDAC1 overexpressed in the WHO III and WHO IV group (Figure 3A), in the IDH1 wildtype group (Figure 4A), and the 1p/19q non-codeletion (Figure 4D) implied that HDAC1 tended to be a detrimental prognostic biomarker in glioma (Lapointe et al., 2018).