AOM/DSS-induced colorectal tumor model and acute DSS treatment

8 to 12 week old mice were injected intraperitoneally with AOM (NCI, Frederick, Maryland, USA) at 12.5 mg/kg body weight. Five days after injection, 2.5% DSS (MW 36 – 50 kDa, MP Biomedicals, Santa Ana, CA, USA) was given in the drinking water for five days, followed by 16 days of regular water. This cycle was repeated twice more and mice were sacrificed ten days after the last complete cycle. The colon was washed with PBS and cut open longitudinally. Tumor polyps were measured under a dissecting microscope and their volume was calculated as 1/2 × length × (width)². For acute DSS treatment 3% DSS was given in drinking water.