Figure 4.

PPM1 induces formation of polyploid breast cancer cells. (a) MDA-MB-231 cells were treated with PPM1 (10 µM) or paclitaxel (100 nM) for 48 or 72 h, and DNA was stained with propidium iodide. Polyploid and subdiploid cells were analyzed by using flow cytometry. Representative histograms in logarithmic and linear scales are shown. (b) and (c) graphs show the percentages of polyploid and apoptotic subdiploid cells, respectively. All data are mean ± SEM, n = 3. Statistical analysis was performed by using the Newman-Keuls test, * p < 0.05, ** p < 0.01, *** p < 0.001.