Figure 1

VPA-mediated cell death in CLL cells. Mononuclear cells isolated from peripheral blood of CLL patients were treated as indicated and analyzed by FACS. (A) Dot blot analyses are shown for FSC/SSC and for annexin V/PI for a representative patient analyzed after 48 h of culture. (B) Cell viability was monitored for 30 patients over 7 days at different concentrations of VPA. The graphs display the decrease in viable cells (annexin V^-/PI^-) under VPA treatment normalized to untreated cells. VPA-treated CLL cells show increased histone acetylation. (C) PBMCs from a CLL patient were left untreated (−) or were cultivated in the presence of different VPA concentrations (0.1, 1, 3 mM) for 48 h. Histone extracts were subjected to Western blot analysis using acetylation-specific antibodies for histones H4 and H3. Equal loading of gels was documented with anti-actin antibody.