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Published on: August 1, 2018

PI3K-based molecular signatures link high PI3K pathway activity with low ER levels in ER+ breast cancer

Alex Sanchez1, Josep Villanueva

  • 1University of Barcelona, Barcelona, Spain.

Expert Review of Proteomics
|December 15, 2010
PubMed

Insights

High PI3K pathway activity may reduce estrogen receptor (ER) levels, driving endocrine resistance in ER(+) breast cancer. Targeting both PI3K and estrogen pathways shows promise for treating resistant breast cancer.

Area of Science:

  • Oncology
  • Molecular Biology
  • Endocrinology

Background:

  • Endocrine therapy resistance is a significant challenge in estrogen receptor-positive (ER(+)) breast cancer, with underlying mechanisms not fully elucidated.
  • The PI3K signaling pathway is frequently dysregulated in cancer and implicated in various resistance mechanisms.

Discussion:

  • This study investigates the link between PI3K pathway activity and ER levels in ER(+) breast cancer.
  • High PI3K pathway activity was found to correlate with decreased ER levels, suggesting a potential mechanism for endocrine resistance.

Key Insights:

  • Development of PI3K-based proteomic and transcriptomic signatures identified an association with low ER levels in 429 ER(+) breast cancer tumors.
  • Functional studies in cancer cell lines supported the hypothesis that elevated PI3K activity contributes to endocrine resistance.

Outlook:

  • Combined inhibition of PI3K and estrogen pathways presents a potential therapeutic strategy for ER(+) breast cancer patients with high growth-factor receptor (GFR) signaling.
  • These findings may offer novel treatment alternatives for endocrine-resistant breast cancer.

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