Retinoic acid downregulates growth, fibronectin and RAR alpha in 3T3 cells: Ha-ras blocks this response and RA metabolism

J Cell Physiol. 1997 Nov;173(2):297-300. doi: 10.1002/(SICI)1097-4652(199711)173:2<297::AID-JCP39>3.0.CO;2-A.

Abstract

Retinoic acid (RA) reduced growth, fibronectin, and retinoic acid receptor (RAR alpha) in NIH 3T3 cells but not in cells transformed by the Ha-ras oncogene. RA lowered RAR alpha transcript and protein, increased RAR beta transcripts, and had no effect on RAR gamma. H-ras transformation downregulated RAR expression and abolished responsiveness to RA. Ha-ras-transformed cells were as active as normal NIH-3T3 cells in RA uptake but were unable to degrade it to medium oxidation product, so that, paradoxically, the resistant cells accumulated 20-30-fold as much RA as the sensitive cells. RA sensitivity/insensitivity correlated with RA metabolism/lack thereof in 15 cell lines in serum-free medium. These data suggest a relationship between RA inhibition of cell growth and intracellular RA metabolism.

MeSH terms

  • 3T3 Cells / cytology*
  • 3T3 Cells / drug effects*
  • 3T3 Cells / metabolism
  • Animals
  • Cell Division / drug effects
  • Fibronectins / metabolism*
  • Genes, ras / physiology
  • Mice
  • Receptors, Retinoic Acid / drug effects
  • Receptors, Retinoic Acid / metabolism*
  • Tretinoin / metabolism
  • Tretinoin / pharmacology*

Substances

  • Fibronectins
  • Receptors, Retinoic Acid
  • Tretinoin