Figure 5.
Nutlin-3 induces p53 activity and cell cycle arrest, but not apoptosis. (A) ZL34 and SPC212 cells were cultured for 24 hours with the indicated concentrations of nutlin-3. Lysates were analyzed by immunoblotting using antibodies specific for p53, phospho-p53 (ser15), MDM2, and p21WAF. Staining of actin was used as loading control. (B) ZL34 cells were cultured with 10 µM nutlin-3 for 48 hours. Cells were fixed and stained with PI before FACS staining of nuclei. Representative data of three independent experiments are shown. (C) ZL34 cells were cultured with 10 µM nutlin-3 or the same volume of DMSO in the presence of 1.2 µM CDDP for 48 hours. Cells were lysed, and caspase-3-like protease activity was measured as in Figure 3D.