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Updated: Jul 10, 2026
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Studying TGF-β Signaling and TGF-β-induced Epithelial-to-mesenchymal Transition in Breast Cancer and Normal Cells
Published on: October 27, 2020
Glucocorticoid receptor changes its cellular location with breast cancer development
Isabel Conde1, Ricardo Paniagua, Benito Fraile
1Department of Cell Biology and Genetics, University of Alcalá, Alcalá de Henares, Madrid. Spain.
Histology and Histopathology
|October 24, 2007
Summary
Glucocorticoid receptor (GR) nuclear expression decreases with breast cancer progression. Mineralocorticoid receptor (MR) is always cytoplasmic, and COX-2 expression is reduced in cancerous lesions compared to benign diseases.
Area of Science:
- Endocrinology
- Oncology
- Molecular Biology
Background:
- Glucocorticoids (GCs) are vital for inflammatory response attenuation and show antiproliferative effects on breast cancer cells.
- GCs, via the intracellular glucocorticoid receptor (GR), can protect mammary epithelia from apoptotic signals.
- Limited data exists on GR, mineralocorticoid receptor (MR), and COX-2 expression in human breast pathologies and their role in tumoral cells.
Purpose of the Study:
- To investigate the expression patterns of GR, MR, and COX-2 in various human breast pathologies.
- To explore the potential relationship between GR, MR, and COX-2 expression during breast cancer development.
- To clarify the role of these proteins in tumoral breast epithelial cells.
Main Methods:
- Immunohistochemistry and Western blot techniques were employed.
- Analysis was performed on 142 human breast tissue samples obtained from mastectomies.
- Expression levels and cellular localization of GR, MR, and COX-2 were assessed.
Main Results:
- Nuclear GR immunoreaction decreased with tumor progression.
- All analyzed samples exhibited cytoplasmic MR immunoreaction.
- COX-2 expression was higher in benign breast diseases than in carcinomatous lesions, with cytoplasmic localization.
Conclusions:
- Breast cancer progression is linked to GR accumulation in the cytoplasm of tumoral cells.
- A decrease in COX-2 expression correlates with advancing breast cancer.
- These findings highlight altered receptor expression during breast tumorigenesis.
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