KU174 mediated induction of selective cytotoxicity and apoptosis in PC3-MM2 prostate cancer cells. Selective cytotoxicity was determined by trypan blue exclusion assay in PC3-MM2 cells (Figure 1A and 1B, left panel) at 24 and six hours, respectively. Normal RPTEC cells dosed for six hours did not show a loss of viability (Figure 1B, right panel). Furthermore, total PC3-MM2 cells (Figure 1A, right panel) were counted following 24 hours of treatment and compared to the number of cells plated at time zero (T = 0) demonstrating potent anti-proliferation of KU174 as low as 100 nanomolar. Further cytotoxicity studies were conducted by flow where viable cells (quadrant I) were compared to cells undergoing necrosis (quadrant II), early apoptosis (quadrant III) or late-stage apoptosis (quadrant IV) by measuring the percent Annexin V and propidium iodide (PI) staining of the parent population for PC3-MM2 cells (Scatterplots Figure 1C) following KU174 treatment. A bar graph of these data along with statistical analysis is shown (Figure 1C, right panel). Columns depict the mean ± SEM from three independent experiments (n = 3), * and ** indicates significant paired t-test P value of < 0.05 and < 0.01 respectively, compared to vehicle-treated control.