HDAC1 and colorectal carcinoma: As we expected, the stimulatory effects of SOX4 on all stem-like properties in HCT-116 and HT-29 cells were significantly abolished by HDAC1 depletion, including in vitro sphere-forming capacity (Fig. 5a), self-renewal capacity (Fig. 5b) the frequency of sphere-forming cells in vitro (Fig. 5c and Additional file 1: Fig. S5b), the frequency of tumor-initiating cells in vivo (Fig. 5d and Additional file 1: Fig. S5c) and the expression of CRC-SCs markers (Fig. S5d and Fig. 5e), which confirmed that HDAC1 plays a primary role in mediating SOX4-induced stemness of CRC cells.