title: Expression pattern of the genes for different members of the heat-shock protein 70 family, ornithine decarboxylase, and c-Ha-ras during the early stages of hepatocarcinogenesis.
abstract: Northern blot analysis with specific probes indicates that, in the liver of normothermic rats under the carcinogenic regimen of Solt and Farber (Nature 263:701, 1976), diethylnitrosamine (DEN), 2-acetylaminofluorene (AAF), and partial hepatectomy (PH), either alone or in combination, do not induce the expression of the heat-shock protein 70 (hsp70) gene family. On the contrary, the inducibility of hsp70 mRNAs in the liver of heat-shocked animals is maintained throughout the treatment, as it is in nodules that are found in the liver 2 weeks posttreatment. The steady-state level of the constitutive hsp70-related cognate protein (hsc73) mRNA, which is known to be particularly high in fast-growing cells, increases above the normal level only during liver regeneration, stays at a high level up to 8 days after hepatectomy, independently of any associated exposure to carcinogenic chemicals, and is practically unchanged in the nodules. Ornithine decarboxylase mRNA increases only in livers of normothermic rats at 16 h of regeneration. The expression of the c-Ha-ras oncogene increases slightly, but steadily, during the carcinogenic treatment and persists at a high level when other changes have subsided.
authors.affiliation: Istituto di Patologia Generale dell Università degli Studi di Milano, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Tacchini
authors.forename: L
authors.initials: L
authors.lastname: Schiaffonati
authors.forename: E
authors.initials: E
authors.lastname: Rappocciolo
authors.forename: G
authors.initials: G
authors.lastname: Cairo
authors.forename: A
authors.initials: A
authors.lastname: Bernelli-Zazzera
mesh_terms: D015073:2-Acetylaminofluorene; D000818:Animals; D015152:Blotting, Northern; D004052:Diethylnitrosamine; D015972:Gene Expression Regulation, Neoplastic; D011905:Genes, ras; D006360:Heat-Shock Proteins / Q000235:genetics*; D006358:Hot Temperature; D008113:Liver Neoplasms / Q000139:chemically induced / Q000235:genetics*; D008114:Liver Neoplasms, Experimental / Q000139:chemically induced / Q000235:genetics*; D008115:Liver Regeneration; D008297:Male; D009955:Ornithine Decarboxylase / Q000235:genetics*; D012334:RNA, Neoplasm / Q000235:genetics; D051381:Rats
chemical_list: D006360:Heat-Shock Proteins; D012334:RNA, Neoplasm; D004052:Diethylnitrosamine; D015073:2-Acetylaminofluorene; D009955:Ornithine Decarboxylase