BALB/c mice fed milk or beef protein: differences in response to 1,2-dimethylhydrazine carcinogenesis.
The development of 1,2-dimethylhydrazine (DMH)-induced colon tumors and immune responses were investigated in male BALB/c mice fed six different equicaloric diets. Milk or beef at a low (11%) or high (33%) level supplied the dietary protein, and corn oil (primarily) at a low (5%) or high (30%) level supplied the fat. Eleven weekly injections of DMH (at 20 mg/kg mouse) or saline were administered. At 59 weeks of age, the milk-fed mice had a significantly higher (P less than or equal to .05) colon tumor incidence than the beef-fed mice, 67 and 16%, respectively. Tumor volume and colon weight in the milk-fed mice were also significantly greater. Low natural killer cell activity against [125I]5-iodo-2'-deoxyuridine-labeled colon tumor cells and high serum blocking of antitumor cell activity were observed in the milk-fed-mice. These mice also exhibited higher T-lymphocyte cytotoxicity against colon tumor cells. These results differ from those of our previous studies and those of numerous epidemiologic investigations.
D019813:1,2-Dimethylhydrazine; D000818:Animals; D001835:Body Weight; D002417:Cattle; D003043:Cocarcinogenesis; D003110:Colonic Neoplasms / Q000139:chemically induced* / Q000276:immunology / Q000473:pathology; D003602:Cytotoxicity, Immunologic; D004032:Diet; D004127:Dimethylhydrazines / Q000633:toxicity*; D007694:Killer Cells, Natural / Q000276:immunology; D008297:Male; D008460:Meat; D008763:Methylhydrazines / Q000633:toxicity*; D051379:Mice; D008807:Mice, Inbred BALB C; D008894:Milk Proteins / Q000494:pharmacology*; D009929:Organ Size
D004127:Dimethylhydrazines; D008763:Methylhydrazines; D008894:Milk Proteins; D019813:1,2-Dimethylhydrazine