Growth Hormone Regulation of the c-myc Gene During Sex-Differentiated Rat Liver Carcinogenesis

  • Inger Porsch-Hällström
  • Jan-Åke Gustafsson
  • Agneta Blank
Conference paper

Summary

The expression of the c-myc gene was analyzed at different stages of rat liver carcinogenesis in the resistant hepatocyte model (RH-model). During promotion of diethylnitrosamine (DEN)-initiated Wistar rats with 2-acetylaminofluorene (2-AAF) and partial hepatectomy (PH), the hepatic c-myc expression was increased in males, but not in females, from one day after PH. Continuous growth hormone (GH) infusion decreased the expression to the level in females. A higher c-myc mRNA level compared with the respective surrounding livers was observed in nodules from males isolated 6 weeks. This elevated c-myc RNA level was also seen in 8 and > 11 months after DEN treatment and in hepatomas, while in females an increased expression was noted only in > 11 month nodules and hepatomas. GH infusion to nodule bearing males decreased c-myc mRNA levels in surrounding livers, and in nodules 8 but not 11 months after DEN.

Keywords

Diethylnitrosamine 

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Copyright information

© Springer-Verlag New York, Inc. 1992

Authors and Affiliations

  • Inger Porsch-Hällström
  • Jan-Åke Gustafsson
  • Agneta Blank

There are no affiliations available

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