Androgens Modulate Bcl-2 Agonist of Cell Death (BAD) Expression and Function in Breast Cancer Cells.

Abstract

Androgen receptor (AR) expression in estrogen receptor-positive (ER+) breast cancer (BC) correlates with lower tumor grade and a better clinical outcome. Additionally, in normal mammary epithelium or ER+ BC preclinical models, androgens counteract basal/ER-dependent proliferation. Here, we report an additional mechanism, underlining the protective role exerted by AR. Specifically, the activation of intracellular AR upregulates the Bcl-2-family protein BAD, and TCGA database analyses show that in ER+ BC, BAD expression is associated with better disease-free survival. Ligand-activated AR influences its own and BAD cellular compartmentalization by enhancing levels in the nucleus, as well as in mitochondrial fractions. In both compartments, BAD exerts unconventional functions. In the nucleus, BAD and AR physically interact and, upon androgen stimulation, are recruited at the AP-1 and ARE sites within the cyclin D1 promoter region, contributing to explaining the anti-proliferative effect of androgens in BC cells. Androgens cause an enrichment in BAD and AR content in the mitochondria, correlated with a decrease in mitochondrial function. Thus, we have defined a novel mechanism by which androgens modulate BAD expression, its mitochondria localization, and nuclear content to force its ability to act as a cell cycle inhibitor, strengthening the protective role of androgen signaling in estrogen-responsive BCs.

• Authors: Catia Morelli, Chiara Chiodo, Marta Claudia Nocito, Alessandro Cormace, Stefania Catalano, Diego Sisci, Rosa Sirianni, Ivan Casaburi, Sebastiano Andò, Marilena Lanzino
• Journal: International journal of molecular sciences (Int J Mol Sci) Vol. 24 Issue 17 (Aug 30 2023) ISSN: 1422-0067 [Electronic] Switzerland
• PMID: 37686282 (Publication Type: Journal Article)

Chemical References

• Androgens
• Estrogens

Topics

• Androgens (pharmacology)
• Cell Death
• Cell Nucleus
• Estrogens
• Cell Cycle
• Neoplasms