Materials and Reagents

1. 8-10 weeks old mice (in-house bred mice mostly C57BL/6 background, both male and female; we also used mice with mixed C57BL/6-129v background to induce colon tumors)
   
2. Azoxymethane (AOM) (Sigma-Aldrich, catalog number: A5486 )
   
3. DSS salt (molecular weight 36,000-50,000 Da) (MP Biomedicals, catalog number: 0126011090-500 g)
   
4. Sterile 1x phosphate-buffered saline (PBS)
   
5. 10% formalin solution (Sigma-Aldrich, catalog number: HT-501128)
   
6. Autoclaved drinking water
   

Equipment

1. 1 ml and 5 ml syringes (ENFA, catalog numbers: JS1 and JS3)
   
2. 10 cm Petri dish, tissue culture grade (BD Biosciences, Falcon^®, catalog number: 353006)
   
3. Needles (25 G for AOM injection and 21 G to wash the colon)
   
4. Digital caliper (Sylvac, catalog number: S_Cal WORK 910.0502.10)
   
5. Dissection equipment (forceps, tweezers, scissors)
   
6. Balance
   
7. Tissue processor (Sakura, catalog number: VIP6-E2)
   

Procedure