Prebiotics modulate microbial composition and ensure a healthy gastrointestinal tract environment that can prevent colon cancer development. These natural dietary compounds are therefore potential chemopreventive agents. Thirty Sprague-Dawley rats (4 months old) were experimentally treated with procarcinogen dimethylhydrazine to induce colon cancer development. The rats were randomly assigned t...

Trypanosoma cruzi infection and nonsteroidal anti-inflammatory drugs inhibit colorectal carcinogenesis by mechanisms not completely known and metallothionein proteins (MTs) may be involved in this process. Sixty-six male Wistar rats weighing 90 to 120 g were randomly divided into seven groups (GI to GVII). GI, GII and GIII animals were subcutaneously infected with 200,000 trypomastigote forms o...

The main objective of the present study was to sequentially analyze growth and morphological characteristics of aberrant crypt foci (ACF) in the rat colon. Sprague-Dawley rats were given a single injection of a carcinogenic dose of 1,2-dimethylhydrazine-HCl and at varying time points ranging from 2 to 57 weeks, groups of 5 rats were terminated. The number and crypt multiplicity of ACF were dete...

a-Difluoromethylornithine (DFMO) treatment has been shown to modify carcinogenesis in many experimental tumor models, including skin, breast, and colon. This study was designed to determine whether DFMO treatment can inhibit experimental mouse colon tumors after carcinogen treatment and whether an associated effect of DFMO on cell proliferation in colon mucosa occurs. Male CDi mice (40 per grou...

The ultimate end-point of a cancer-inducing exposure to a carcinogen is the appearance of a localized collection of cells (i) undergoing inappropriate proliferation, (ii) expanding locally and invading the surrounding tissue and (iii) releasing cells that generate in turn new collections of proliferating cells in distant sites. Most cancers are made up of heterogeneous cell populations with con...

BACKGROUND AND AIMS Diminished folate status is associated with enhanced colorectal carcinogenesis. This study investigated the potential chemopreventive role of dietary folate in the dimethylhydrazine colorectal cancer model. SUBJECTS AND METHODS Sprague-Dawley rats were fed diets containing either 0, 2 (daily dietary requirement), 8 or 40 mg folate/kg diet for 20 weeks. After five weeks of ...

In patients with ulcerative colitis, epidemiolÃ3gica!work has suggested an association between low folate status and an increased risk of colonie neoplasia. The aim of the present study was to determine if experimen tal folate deficiency increases the likelihood of developing neoplasia in rats treated with the carcinogen dimethylhydrazine. Weanling male Sprague-Dawley rats were fed with an amin...

M1 antigens, associated with adult rat surface gastric epi thelium and which are present in fetal but not adult distal colon, were investigated in this colonie mucosa during carcinogenesis. Fifty Wistar rats were given s.c. injections of 1,2-dimethylhydrazine for 28 weeks. Using an immunohistochemical method, M1 antigens associated with goblet cells were shown to be present after 2 weeks of 1,2...

Bioassays of amosite, short-range (SR), intermediate-range (IR) or intermediate-range chrysotile asbestos in combination with the intestinal carcinogen 1,2-dimethylhydrazine dihydrochloride (DMH) were conducted with male and female Syrian golden hamsters. Amosite and both forms of chrysotile asbestos were administered at a concentration of 1% in pelleted diet for the entire lifetime of the hams...