1d-induced apoptosis in HCT116 cells is partially dependent on p53.

<p>(A) HCT116 (p53^+/+) and HCT116-p53^-/- cells were treated with 1 μg/ml of <b>1d</b> or DMSO (control) for the indicated time periods and then stained with crystal violet. (B) HCT116 cells were treated with <b>1d</b> at the indicated concentrations or DMSO for 48 h and then evaluated using the MTT assay. Data are the means of 2 independent experiments ± SEM. (C) The percentage of apoptotic cells in HCT116 cells treated with 5 μg/ml of <b>1d</b> or DMSO for 24 hr followed by flow cytometry analysis. Data are the means of 2 independent experiments ± SEM. *, p<0.05 when comparing HCT116 and HCT116-p53^-/- cells. (D) HCT116 cells were treated with 5 μg/ml of <b>1d</b> for the indicated durations and then analyzed using Western blot using a caspase 3 antibody. (E) The cells were treated with 5 μg/ml of <b>1d</b> and then subjected to real-time PCR analysis. Data are the means of 2 independent experiments ± SEM (n = 2). *, p<0.05; **, p<0.005 when comparing with vehicle controls or when comparing HCT116-p53^+/+ and HCT116-p53^-/- cells.