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Updated: Jul 10, 2026
16:24
Profiling of Estrogen-regulated MicroRNAs in Breast Cancer Cells
Published on: February 21, 2014
The estrogen receptor: more than the average transcription factor
1Manitoba Institute of Cell Biology, University of Manitoba, Winnipeg, Canada.
Summary
The human estrogen receptor (ER) regulates gene transcription in response to ligands. Its levels and ligand-binding status impact estrogen-responsive gene expression in breast cancer and other tissues.
Area of Science:
- Molecular Biology
- Endocrinology
- Cancer Research
Background:
- The human estrogen receptor (ER) is a crucial steroid nuclear receptor.
- ER is found in breast cancer and various other tissues.
- ER localization within the nucleus varies based on ligand binding.
Purpose of the Study:
- To elucidate the mechanisms of estrogen receptor-mediated gene regulation.
- To understand the role of ligand binding in ER function and stability.
- To investigate ligand-independent ER activation pathways.
Main Methods:
- Analysis of ER localization and association with the nuclear matrix.
- Study of transcriptional regulation via coactivator and corepressor recruitment.
- Investigation of the mitogen-activated protein kinase (MAPK) pathway in ER activation.
- Assessment of ligand effects on ER mRNA and protein levels and stability.
Main Results:
- Ligand-bound ER is tightly associated with the nuclear matrix and regulates transcription.
- ER mediates ligand-independent transcriptional activation through the MAPK pathway.
- Ligands modulate ER levels and stability by affecting ER mRNA and protein.
- ER levels and bound ligand type directly influence estrogen-responsive gene transcription.
Conclusions:
- Estrogen receptor function is dynamically regulated by ligand binding and cellular localization.
- Both ligand-dependent and ligand-independent pathways contribute to ER's role in gene expression.
- Understanding ER regulation is critical for targeting breast cancer and other estrogen-sensitive conditions.
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