Cytotoxicity assay, cell cycle, and annexin V analysis of HUT78 cell line treated with other HDIs. (A) Cytotoxicity assay was performed on HUT78 cells treated for 3 days with varying concentrations of sodium butyrate (NaBu), trichostatin A (TSA), or MS-275 in the presence or absence of valspodar. Data are shown on a logarithmic scale. (B) Cell cycle analysis and annexin V staining shown for cells treated for 48 hours. (C) HUT78 cells were treated for 48 hours with the amount of depsipeptide, TSA, NaBu, or MS-275 as indicated. Whole cell lysates were prepared, and 10 μg/mL of proteins were separated by PAGE. Immunoblots were performed using antibodies against acetylated histone H3, demonstrating histone deacetylase activity of the individual HDIs, and p21, demonstrating the induction of gene expression by each individual HDI.