Figure 3.

Urolithin A leads to p53/p21-dependent senescence-like growth arrest in HCT116 cells. (A) WT and p53−/− HCT 116 cells were subcultivated in the continuous presence of solvent (0.1% DMSO) or 20 µM urolithin A (medium exchange every other day), and CPD were plotted against time of cultivation. Representative curves of three independent experiments with consistent results are depicted. (B) Cells after 25 days of cultivation in DMSO or 20 µM Uro A containing growth medium were photographed. (C) WT, p53−/− and p21−/− were chronically treated with 20 µM urolithin A prior to fixation and staining for SA-β-gal. The percentage of blue (here: dark) stained and hence SA-Gal positive cells from at least five different samples is summarized and depicted in the bar graph. Only urolithin A-treated WT, p53−/− or p21−/− HCT116 cells are shown.