AN EARLY EVENT ASSOCIATED WITH LIVER CARCINOGENESIS INVOLVING LOSS OF A POLYPEPTIDE THAT BINDS CARCINOGEN

  • 1 January 1980
    • journal article
    • research article
    • Vol. 40  (12) , 4688-4693
Abstract
This report describes an early and direct action of oncogenic agents and its apparent consequences. The chemical carcinogen interacts principally with a specific polypeptide in livers of normal rats. Short-term ingestion of carcinogen causes marked reductions in the concentrations of the carcinogen:polypeptide complex and the polypeptide itself. This action and its consequences are unique in several ways. The chemical carcinogen is directly involved in the event. Three kinds of liver carcinogens act in this way: the aromatic amide, N-2-fluorenylacetamide (2-acetylaminofluorene); the aminoazo dye, 3''-methyl-4-dimethylaminoazobenzene: and the amino acid analog, ethionine. Interaction of the carcinogen with a specific polypeptide is involved. The carcinogen:polypeptide complex and the polypeptide itself undergo marked reductions in concentration during hepatocarcinogenesis by the 3 types of carcinogens. The consequences of the interaction are sensitive indicators unusually early during liver carcinogenesis. The target polypeptide has a MW of 14,700, similar to those of known polypeptide growth regulators.