Figure 1.

Proliferating and drug-induced senescent PC3 prostate cancer cells. Senescent cancer cells exhibit the characteristic morphology and increased SA-β-gal activity seen in replicative senescent cells. PC3 cells were cultured in drug-free medium or in medium containing 250 nM quinone diaziquone for 3 days followed by 2 days in drug-free medium (13), fixing, and staining (12). Cells were visualized under ×200 magnification using phase contrast microscopy. Scale bar = 100 μm; SA-β-gal = senescence-associated β-galactosidase.