Estradiol increases IRS-1 gene expression and insulin signaling in breast cancer cells

Biochem Biophys Res Commun. 2001 Nov 2;288(3):685-9. doi: 10.1006/bbrc.2001.5815.

Abstract

This study demonstrates how the potentiating effects of E2 on insulin signaling in ER-positive breast cancer cells are consequent to an enhanced IRS-1 expression [corrected]. It induces an increase of both PI-3K/AKT and ERK1/2 activities. A direct action of E2 in the regulating mouse IRS-1 gene is also investigated in both Chinese hamster ovary and MCF-7 cells that are transfected with mouse IRS-1 regulatory sequences. The authors have reported, for the first time, how E2 induction of IRS-1 mRNA was correlated with a direct positive regulatory role of E2 on the IRS-1 promoter. This effect seems to be not strictly related to the cell type.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Analysis of Variance
  • Breast Neoplasms
  • Estradiol / pharmacology*
  • Gene Expression Regulation / drug effects*
  • Humans
  • Insulin / physiology*
  • Insulin Receptor Substrate Proteins
  • Phosphoproteins / genetics
  • Phosphoproteins / metabolism*
  • Phosphorylation
  • Promoter Regions, Genetic / drug effects*
  • Promoter Regions, Genetic / genetics
  • RNA, Messenger / drug effects
  • RNA, Messenger / metabolism
  • Signal Transduction / drug effects
  • Signal Transduction / physiology
  • Tumor Cells, Cultured
  • Tyrosine / metabolism

Substances

  • IRS1 protein, human
  • Insulin
  • Insulin Receptor Substrate Proteins
  • Irs1 protein, mouse
  • Phosphoproteins
  • RNA, Messenger
  • Tyrosine
  • Estradiol