LBH589 induces expression of GADD45G mRNA and enhances acetylation of histones at the GADD45G promoter in MOLT-4 and Reh cells. (A) Following treatment with 50 nM LBH589 for 24 hours, TaqMan real-time PCR was performed on MOLT-4 and Reh cells. The mRNA levels were normalized to levels of β-actin mRNA. Results summarized in the bar graphs are representative of 3 independent experiments plus the standard deviation. (B) Following treatment with 50 nM LBH589 for 24 hours, ChIP assay was performed on MOLT-4 and Reh cells. DNAs purified from the sheared cross-linked chromatin lacking primary antibody (INPUT) and immunoprecipitated with anti–acetyl-histone H3 or anti–acetyl-histone H4 antibodies were used as PCR templates to amplify the GADD45G promoter regions from −567 to +6. Results are representative of 3 independent experiments. (C) Cells were transfected with Cy3-labeled GADD45G siRNA or negative control siRNA, and 24 hours later Cy3-positive cells were sorted and treated with 50 nM LBH589. At 48 hours after treatment, the percentage of nonviable cells was determined by annexin V/PI staining and flow cytometry. Values represented as bar graphs are the means of 3 independent experiments plus the standard deviation. Asterisks indicate statistical significance (P < .05).