title: Induction of c-fos and c-myc oncogene expression in the pyloric mucosa of rat stomach by N-methyl-N'-nitro-N-nitrosoguanidine and taurocholate.
abstract: The induction of c-fos and c-myc expression in the pyloric mucosa of 8-week-old F344 male rats after oral administration of the glandular stomach carcinogen, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), or the tumor-promoter, taurocholate, was examined by Northern blotting. MNNG at doses of 5-50 mg/kg body weight dose-dependently induced transient increase of up to 30-fold c-fos expression with a maximum after 30 min, and of 8-fold c-myc expression with a maximum after 3 h. It also induced up to 3-fold increase in S-phase cells in the proliferation zone of the pyloric mucosa after 16 h. Similar effects were observed with sodium taurocholate at doses of 200-800 mg/kg body weight. These results suggest that c-fos and c-myc oncogenes play a role in stomach carcinogenesis.
authors.affiliation: Department of Molecular Oncology, Institute of Medical Science, University of Tokyo, Japan.
authors.forename: C
authors.initials: C
authors.lastname: Furihata
authors.forename: A
authors.initials: A
authors.lastname: Yamakoshi
authors.forename: A
authors.initials: A
authors.lastname: Hatta
authors.forename: M
authors.initials: M
authors.lastname: Tatematsu
authors.forename: H
authors.initials: H
authors.lastname: Iwata
authors.forename: K
authors.initials: K
authors.lastname: Hayashi
authors.forename: K
authors.initials: K
authors.lastname: Umezawa
authors.forename: T
authors.initials: T
authors.lastname: Matsushima
mesh_terms: D000818:Animals; D002273:Carcinogens; D005753:Gastric Mucosa / Q000378:metabolism*; D015870:Gene Expression / Q000187:drug effects; D016762:Genes, fos; D016259:Genes, myc; D008297:Male; D008769:Methylnitronitrosoguanidine; D011706:Pyloric Antrum / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D011916:Rats, Inbred F344; D013656:Taurocholic Acid; D013997:Time Factors
chemical_list: D002273:Carcinogens; D012333:RNA, Messenger; D008769:Methylnitronitrosoguanidine; D013656:Taurocholic Acid