25,000 cells/well were plated and 24 hours later they were treated with DFMO (5 mM) + Spermidine (SPD; 10μM), PTI (30 μM) + Spermidine (SPD; 10 μM) and PTI (30 μM) + Spermidine (SPD; 10 μM) + DFMO (5 mM) or each treatment alone (n=10 on each sample). On days 3 and 5, the cell culture media was changed to replenish with the same concentration of DFMO, Spermidine and PTI as on day 1. Control was also replenished with fresh media. Samples were counted on days 1 or 7 after treatment. Asterisk (*) indicates statistical difference between the samples in 1 vs 7-day of proliferation, whereas the circle (•) indicates statistical difference between the samples in 7 day of proliferation and control (p<0.05; Wilcoxon Signed Ranks Test).