RT4 cells were incubated for 4 hr in transfection medium (control), with PPCat-siNT (100 nM) or PPCat-siSurvivin (100 nM), followed by 2 hr treatment with complete medium or MMC (0.1 and 3 µM). At 48 hr post-treatment, cells were collected and analyzed for survivin mRNA and protein levels. Ctl: control. –si: no siRNA, siNT: nontarget siRNA, siSur: survivin siRNA. Data for mRNA levels are mean+1 SD (n=3 experiments, with triplicate samples per experiment). Data for protein levels are mean+1 SD (n=3 experiments, single sample per experiment). *p<0.05 compared to control. **p<0.05 compared to MMC and MMC+PPCat-siNT.