title: Lymphoma induction by heterocyclic amines in E mu-pim-1 transgenic mice.
abstract: The usefulness of transgenic E mu-pim-1 mice bearing in their genome the pim-1 oncogene supplemented with an upstream immunoglobulin enhancer and a downstream murine leukaemia virus long terminal repeat, as sensitive test organisms was studied in two short-term carcinogenicity studies. The mice were fed standard diet Altromin 1314 supplemented either with 0.03% 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) for 7 months or with 0.03% 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) for 6 months. PhIP and IQ are heterocyclic amines formed during cooking of meat and fish and are mutagenic to bacteria and cultured mammalian cells. PhIP is a potent mouse lymphomagen, while IQ is a liver, lung and forestomach carcinogen in mice. We found that transgenic E mu-pim-1 mice are highly susceptible to PhIP induced lymphomagenesis but do not respond to IQ treatment. PhIP feeding of E mu-pim-1 mice not only increased the total number of T-cell lymphomas but also decreased the latency time compared to either transgenic or wild-type controls. The effect was most pronounced in the treated female E mu-pim-1 mice, which showed a higher incidence of PhIP induced T-cell lymphomas than transgenic males and a strongly reduced latency period after PhIP treatment compared to non-transgenic mice. Our results suggest that the transgenic E mu-pim-1 mouse may be a useful model for short-term carcinogenicity screening of potential genotoxic carcinogens having the lymphoid system as target tissue. Carcinogens that do not target this tissue, like IQ, however will not be recognised.
authors.affiliation: National Food Agency, Institute of Toxicology, Søborg, Denmark.
authors.forename: I K
authors.initials: IK
authors.lastname: Sørensen
authors.forename: E
authors.initials: E
authors.lastname: Kristiansen
authors.forename: A
authors.initials: A
authors.lastname: Mortensen
authors.forename: C
authors.initials: C
authors.lastname: van Kreijl
authors.forename: R H
authors.initials: RH
authors.lastname: Adamson
authors.forename: S S
authors.initials: SS
authors.lastname: Thorgeirsson
mesh_terms: D000818:Animals; D002273:Carcinogens / Q000633:toxicity*; D005260:Female; D007093:Imidazoles / Q000633:toxicity*; D008223:Lymphoma / Q000139:chemically induced* / Q000473:pathology; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D051573:Proto-Oncogene Proteins c-pim-1; D011804:Quinolines / Q000633:toxicity*; D012737:Sex Factors
chemical_list: D002273:Carcinogens; D007093:Imidazoles; D011518:Proto-Oncogene Proteins; D011804:Quinolines; C029216:2-amino-3-methylimidazo(4,5-f)quinoline; C049584:2-amino-1-methyl-6-phenylimidazo(4,5-b)pyridine; C496636:Pim1 protein, mouse; D017346:Protein Serine-Threonine Kinases; D051573:Proto-Oncogene Proteins c-pim-1