To confirm the effect of CHI on the expression of HDAC1 in MM cells, ARP-1 and XG1 were treated with CHI for 48 hours, Western blot showed that CHI was effective in decreasing HDAC1 in both ARP-1 and XG1 cells (Figure 1E), and moderately or faintly decreased the expression of HDAC2 or HDAC8 protein in ARP-1 and XG1 cells, respectively (Supplementary Figure S2). Here, HDAC2 is linked to Miyoshi myopathy.