This observation was in line with increased levels of acetylated tubulin in vivo (Figure 1c) and increased levels of acetylated histone 3 (lysine 9) in T-ALL cells treated in vitro with Givinostat (Supplementary Figure S3) and corroborates the observation that Givinostat inhibits HDAC activity both in poor and good responders. Here, HDAC9 is linked to acute lymphoblastic leukemia.