Histological and immunohistochemical observations of mucin-depleted foci (MDF) stained with Alcian blue, in rat colon carcinogenesis induced with 1,2-dimethylhydrazine dihydrochloride

Cancer Sci. 2004 Oct;95(10):792-7. doi: 10.1111/j.1349-7006.2004.tb02183.x.

Abstract

The usefulness of mucin-depleted foci (MDF), which have recently been proposed as a new preneoplastic biomarker in rat colon carcinogenesis, was histologically investigated in rat colonic tissues treated with 1,2-dimethylhydrazine dihydrochloride (DMH). The relationship among aberrant crypt foci (ACF), MDF and beta-catenin accumulated crypts (BCAC) was examined by comparing the corresponding computer-captured images. Twelve male F344 rats were given DMH s.c. at a dose of 40 mg/kg body weight, once a week for 2 weeks, and randomly divided into two groups. Rats in group 1 were given normal drinking water, while those in group 2 were given drinking water containing indomethacin (IND) at 16 ppm for 6 weeks. All animals were sacrificed 8 weeks after the first DMH treatment. The resected colons were fixed in 10% formalin, and stained with Alcian blue for observation of ACF and MDF. Histological and immunohistochemical analysis revealed that the numbers of ACF, MDF and overlapping lesions in group 2 (treated with IND) were significantly decreased, compared with those in group 1. The number of BCAC in group 2 was also significantly lower than that in group 1. The reduction (61.5%) of MDF by IND was much greater than that (29.3%) of ACF. Analyses of the computer-captured images indicated that MDF had more frequent dysplastic changes and overexpression of beta-catenin than did ACF. MDF having over 4 crypts or MDF with the appearance of ACF corresponded well to BCAC. These results suggest that MDF may be useful as an early biomarker in colon carcinogenesis.

Publication types

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

MeSH terms

  • 1,2-Dimethylhydrazine
  • Alcian Blue
  • Animals
  • Biomarkers, Tumor / analysis
  • Carcinogens
  • Colonic Neoplasms / chemically induced
  • Colonic Neoplasms / metabolism*
  • Colonic Neoplasms / pathology*
  • Cytoskeletal Proteins / analysis
  • Image Processing, Computer-Assisted
  • Immunohistochemistry
  • Male
  • Mucins / analysis*
  • Precancerous Conditions / metabolism
  • Precancerous Conditions / pathology
  • Rats
  • Rats, Inbred F344
  • Staining and Labeling / methods
  • Trans-Activators / analysis
  • beta Catenin

Substances

  • Biomarkers, Tumor
  • Carcinogens
  • Ctnnb1 protein, rat
  • Cytoskeletal Proteins
  • Mucins
  • Trans-Activators
  • beta Catenin
  • 1,2-Dimethylhydrazine
  • Alcian Blue