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Systems Biology of Metabolic Regulation by Estrogen Receptor Signaling in Breast Cancer
10:36

Systems Biology of Metabolic Regulation by Estrogen Receptor Signaling in Breast Cancer

Published on: March 17, 2016

Protein pathway activation mapping reveals molecular networks associated with antiestrogen resistance in breast

Ton van Agthoven1, Marcia F E Godinho, Julia D Wulfkuhle

  • 1Department of Pathology, Josephine Nefkens Institute, Erasmus MC-University Medical Center Rotterdam, The Netherlands. a.vanagthoven@erasmusmc.nl

International Journal of Cancer
|February 14, 2012
PubMed

Insights

Breast cancer antiestrogen resistance (BCAR) genes impact signaling pathways. Understanding these activated pathways, like AKT and ERBB, in tamoxifen-resistant cells offers insights for new targeted breast cancer treatments.

Area of Science:

  • Oncology
  • Molecular Biology
  • Cell Signaling

Background:

  • Breast cancer antiestrogen resistance (BCAR) genes are clinically relevant.
  • BCAR genes associate with tamoxifen resistance and tumor aggressiveness.
  • Changes in protein signaling networks induced by BCAR genes may explain antiestrogen resistance.

Purpose of the Study:

  • To investigate changes in protein signaling network activation status in breast cancer cells with BCAR gene alterations.
  • To gain insight into the molecular mechanisms underlying antiestrogen resistance.

Main Methods:

  • Utilized ZR-75-1 and MCF7 breast cancer cell lines, genetically modified to overexpress specific BCAR genes.
  • Employed reverse-phase protein microarrays with 78 antibodies to analyze key signal transduction pathways.
  • Assessed activation and expression levels of signaling proteins involved in tumorigenesis.

Main Results:

  • Tamoxifen-resistant cell lines showed increased phosphorylation in proliferation and survival pathways, including AKT and Forkhead box O1/3.
  • Overexpression of BCAR4 led to activation of ERBB2, ERBB3, focal adhesion kinase, and SHC.
  • Significant alterations were observed in activated AMPK alpha1, cyclins, STAT5, STAT6, ERK1/2, and BCL2.

Conclusions:

  • The study identified specific kinase-substrate markers and systemically activated signaling pathways involved in tamoxifen resistance.
  • The findings provide insights into breast cancer progression and antiestrogen resistance mechanisms.
  • This knowledge could facilitate the development of novel targeted therapies for breast cancer.

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