Decrease in size of azoxymethane induced colon carcinoma in F344 rats by 180-day fermented miso

Oncol Rep. 2005 Dec;14(6):1559-64.


The present study was designed to investigate the effects of fermented miso (fermented soybean paste) on the induction of colon tumors by azoxymethane (AOM) in male F344 rats. A total of 91 rats, 6 weeks of age, were divided into 5 groups and given weekly subcutaneous injections of AOM (15 mg/kg body wt) for 3 weeks. The animals were placed on diets one week before the first AOM dose: commercial normal control MF diet or a diet containing 10% 2-year, 180-day fermented, or 3-4-day fermented miso. There were no differences in body and organ weights, and no aberrant crypt foci (ACF) among carcinogen-treated groups at week 25. The rates of tumor incidence were 45%, 85%, 75% and 60% with the 2-year, 180-day, and 3-4-day fermented miso and MF, respectively, and those for colon tumors were 34%, 55%, 60% and 55%, respectively. The size of well-differentiated adenocarcinomas and total (well differentiated and signet ring cell) adenocarcinomas in the 180-day fermented miso group was significantly smaller than that in the 2-year fermented miso and MF+AOM groups. Nuclear staining of beta-catenin in colon tumors was increased for the 3-4-day fermented miso compared to the 180-day fermented miso. Cdx2 staining tendency was decreased in colon tumors and adenocarcinomas compared to normal mucosa and ACF, which stained in 100% of cases. In addition, the PCNA index was significantly reduced in the 180-day group compared with those groups receiving the 3-4-day fermented miso and MF diet. The germinal region was also decreased. The present results indicate that dietary supplementation with 180-day fermented dietary miso could act as a chemopreventive agent for colon carcinogenesis.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Azoxymethane / administration & dosage
  • Azoxymethane / toxicity
  • Carcinogens / administration & dosage
  • Carcinogens / toxicity
  • Cell Proliferation / drug effects
  • Colonic Neoplasms / chemically induced
  • Colonic Neoplasms / pathology
  • Colonic Neoplasms / prevention & control*
  • Dietary Supplements*
  • Fermentation
  • Immunohistochemistry
  • Injections, Subcutaneous
  • Intestinal Mucosa / drug effects
  • Intestinal Mucosa / metabolism
  • Intestinal Mucosa / pathology
  • Male
  • Proliferating Cell Nuclear Antigen / analysis
  • Rats
  • Rats, Inbred F344
  • Soy Foods*
  • Time Factors
  • beta Catenin / analysis


  • Carcinogens
  • Proliferating Cell Nuclear Antigen
  • beta Catenin
  • Azoxymethane