HDAC1 and glioblastoma: A large number of researches have proven that significant nuclear expression of histone deacetylase 1 (HDAC1) occurred in GBM cells during the process of tumor progression, recurrence, and metastasis (Bhat et al., 2008; Kim et al., 2008; Campos et al., 2011; Li et al., 2016, 2018a; Zhang et al., 2016; Staberg et al., 2017; He et al., 2019; Natsume et al., 2019).