Scheme 1.

Schematic outline of the experimental design. Traumatization of the urothelium was performed by intravesical treatment with poly-l-lysine (PLL). MB49 cancer cells were then introduced into the bladder lumen and animals were sacrificed after 2 h, 1 day, 3 days, and 3 weeks. Upright arrows demonstrate the introduction of the catheter and downward arrows demonstrate time points of sample collections. Numbers I, II, III, and IV denote animal groups I to IV.