Figure 1.

Treatment schedule and classical HDACs and their inhibitors. (A) Treatment schedule of NB4 cells. Co-treatment implies that cells were treated together with ATRA and HDACi for 24 h, for example, ATRA 24 h and VPA 24 h. Pre-treatment indicates that cells were incubated for 24 h with ATRA, followed by a 24-h VPA treatment, during which ATRA stayed on the cells, for example, ATRA 48 h and VPA 24 h. (B) The figure shows the three classes of HDACs (I, II, and IV) that depend on Zn²⁺ for their catalytic activity. Members of these HDACs can be inhibited by HDACi used in this study. The data are derived from a study by Bradner et al (2010). They tested HDACs 1–9, the inhibition of HDAC10 and HDAC11 is inferred from a literature data search.