Figure 3.

CPT-mediated increase in p53 levels and apoptosis is augmented in VHL-competent cells. (a) The 786-O and RCC4 cells and their VHL-expressing counterparts were treated with increasing concentrations of CPT for 24 h. Whole-cell lysates were assayed by western blot for p53 and phosphorylated-S15-p53 proteins and cleaved PARP. Actin was used as a loading control. (b) The 786-O and 786-O/VHL cells were treated with 100 nM CPT or vehicle for 24 h, fixed, stained with propidium iodide and the percentage (%) of cells in subG1 was assessed by flow cytometry. Mean±S.E. of three replicates is shown