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Updated: Sep 28, 2026

Primary Culture of Rat Adrenocortical Cells and Assays of Steroidogenic Functions
04:33

Primary Culture of Rat Adrenocortical Cells and Assays of Steroidogenic Functions

Published on: March 12, 2019

Mutant K-ras oncogene regulates steroidogenesis of normal human adrenocortical cells by the RAF-MEK-MAPK pathway

C-H Wu1, Y-F Chen, J-Y Wang

  • 1Graduate Institute of Medicine, Kaohsiung Medical University Kaohsiung, 80317, Taiwan.

British Journal of Cancer
|November 16, 2002
PubMed

Insights

Active K-ras oncogenes boost cortisol production and cell proliferation in human adrenocortical cells. This occurs via the Raf-MEK-MAPK pathway, influencing steroidogenesis.

Area of Science:

  • Endocrinology
  • Molecular Biology
  • Oncology

Background:

  • Previous studies indicated K-ras mutants increase cortisol production and cause cell transformation.
  • The K-ras oncogene plays a role in cell signaling pathways relevant to cell growth and differentiation.

Purpose of the Study:

  • To investigate the effect of the active K-ras oncogene on cortisol production in normal human adrenocortical cells.
  • To elucidate the signaling pathway involved in K-ras-mediated steroidogenesis.

Main Methods:

  • Inducible expression of mutant K-ras in human adrenocortical cells using isopropyl thiogalactoside (IPTG).
  • Western blot analysis to assess protein phosphorylation (c-Raf-1, MAPK).
  • Quantitative analysis of mRNA levels for steroidogenic enzymes (P450(SCC), P450(c17), 3betaHSD).
  • Inhibition studies using PD098059 (MEK inhibitor) and lovastatin (Ras inhibitor).

Main Results:

  • IPTG induction led to time-dependent increases in RasGTP levels.
  • Elevated phosphorylation of c-Raf-1 and MAPK was observed.
  • mRNA levels of P450(SCC), P450(c17), and 3betaHSD significantly increased.
  • Cortisol levels and steroidogenic enzyme mRNA increases were reversed by PD098059 and lovastatin.

Conclusions:

  • Active mutant Ras enhances cell proliferation and steroidogenesis in adrenocortical cells.
  • The Raf-MEK-MAPK signaling pathway mediates K-ras-induced steroidogenesis.
  • K-ras mutants influence adrenocortical steroidogenesis regulation via the RAF-MEK-MAPK pathway.

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