Colon cancer is known as the third most widespread cancer in the world. The interaction of heme-iron and ascorbic acid (AA) in colon carcinogenesis is not evident. Hemin (ferric chloride heme) is an iron-containing porphyrin with chlorine that can be formed from a heme group. The purpose of this study was to investigate the protective effect of AA on the formation of pre-neoplastic lesions induced by azoxymethane (AOM)/dextran sodium sulfate (DSS) plus hemin in mice. Forty-five ICR male mice were divided into three experimental groups; AOM/ DSS treatment (control group), hemin (2 g hemin/kg of b.w.), hemin + AA (1.0% in drinking water). The mice had three s.c. injections (0–2nd weeks of the experiment) of AOM (10 mg/kg b.w.) weekly and 2% DSS as drinking water for the next one week and the animals fed on AIN-76A purified rodent diet for 6 weeks. The numbers of aberrant crypt foci (ACF) and aberrant crypts (ACs) in colonic mucosa were counted after methylene blue staining. Lipid peroxidation in feces was measured by the thiobarbituric acid-reactive substances (TBARS) assay. The numbers of ACF and ACs per colon significantly increased in Hemin group compared to the control group. However, the numbers of ACF and ACs per colon notably decreased in hemin + AA group compared to the control group or hemin group (p<0.05). In feces, the TBARS value of hemin group was higher than the control group (p<0.01). The TBARS value of hemin + AA group was slightly decreased compared to Hemin group. These results indicate that hemin can promote the experimental colon carcinogenesis in ICR mice. On the other hand, additional supplement of AA via drinking water has a protective effect against the colon carcinogenesis. The related mechanisms need to be illustrated by further studies in future.

Introduction
Materials and Methods
    Materials
    Animals and experimental diets
    Experimental design
    Total number of aberrant crypt and aberrant cryptfoci count
    Feces preparation
    Thiobarbituric acid reactive substances (TBARS)assay
    Histopathological examination
    Statistical analysis
Results
    Changes in body weights
    Total number of aberrant crypt (AC) and aberrantcrypt foci (ACF) count
    TBARS values in feces
    Histopathology
Discussion
References

• Ye-Seo Jeong(College of Veterinary Medicine and Research Institute of Veterinary Medicine, Chungbuk National University)
• Eun Young Kim(Korea Food Culture Promotion Association)
• Jae-Hwang Jeong(Department of Biotechnology and Biomedicine, Chungbuk Province College)
• Sang Yoon Nam(College of Veterinary Medicine and Research Institute of Veterinary Medicine, Chungbuk National University)
• Beom Jun Lee(College of Veterinary Medicine and Research Institute of Veterinary Medicine, Chungbuk National University) Corresponding author