Androgen has dual effects on BC via different metabolic pathways, and the role of the androgen receptor (AR) in BC also depends on cell subtype and downstream target genes.
Studies targeting the androgen receptor (AR) signaling pathway in aromatase inhibitor (AI)-resistant breast cancer are limited.Bicalutamide, one of the commonly used AR inhibitors in prostate cancer, in combination with AI, did not show synergistic activity in patients with estrogen receptor-positive and AI-resistant disease in this phase II, single-arm study.The clinical benefit rate and objective response rate at 6 months were 16.7% and 0%, respectively, and the study was terminated after the first stage.
Androgen treatment inhibits ER signaling in ER+/AR+ breast cancer cell lines, and AR expression is associated with improved survival for this subtype in epidemiologic studies.
Treatment of MDA-MB-453 with CREBBP/EP300 bromodomain inhibitors downregulates the expression of an AR-dependent signature distinctive of breast cancer tumors that express AR and causes a decrease in H3K27ac levels at AR-binding sites.
Phase Ib patients (ER+ or TNBC) with AR+ breast cancer received 160 mg enzalutamide in combination with taselisib to determine dose-limiting toxicities and the maximum tolerated dose (MTD).
Unlike canonical AR signaling which is inhibited by enzalutamide, non-canonical AR activity is not effectively antagonized by enzalutamide, and this has important implications in the design of future AR-targeted clinical trials in endocrine-resistant breast cancer.
The positivities of estrogen receptor, progesterone receptor, and androgen receptor were lower (p < 0.001, p = 0.03, and p < 0.001, respectively), and the triple-negative (TN) BCs rates were higher (p < 0.01) in the AYA group.
In this review, we aim to address the importance of the AR in BCa diagnosis and prognosis, current AR-targeting approaches in BCa, and the potential for AR-downstream molecules to serve as therapeutic targets.
In this study, the diagnostic utility of a panel of SOX10, GATA3, and androgen receptor (AR) in MBC negative for estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 was evaluated and compared with the expression of these markers in the matched primary breast cancer.
A population pharmacokinetic analysis of the oral CYP17 lyase and androgen receptor inhibitor seviteronel in patients with advanced/metastatic castration-resistant prostate cancer or breast cancer.
In conclusion, next to AR expression, incorporation of additional tumor characteristics will potentially make AR targeting a more valuable therapeutic strategy in breast cancer.
Furthermore, inhibition of 17β-HSD7 increases the expression of AR gene which is considered as a marker for better prognosis in ER + breast cancer, while maintaining ERα level.
We characterized and tested a novel therapy to an AR-governed target in breast cancer.<b>Experimental Design:</b> We evaluated the expression of prototypical AR gene products human kallikrein 2 (hK2) and PSA in breast cancer models.
The androgen receptor (AR) is present in most breast cancers (BC), but its exploitation as a therapeutic target has been limited.This study explored the activity of dehydroepiandrosterone (DHEA), a precursor being transformed into androgens within BC cells, in combination with an aromatase inhibitor (to block DHEA conversion into estrogens), in a two-stage phase II study in patients with AR-positive/estrogen receptor-positive/human epidermal growth receptor 2-negative metastatic BC.Although well tolerated, only 1 of 12 patients obtained a prolonged clinical benefit, and the study was closed after its first stage for poor activity.
Using immunohistochemistry, ANK3 protein expression was evaluated in large (n = 982) cohort of early-stage BC with long-term follow-up and compared with clinicopathological characteristics and its prognostic value in the whole cohort and the subgroups stratified by AR protein expression.
Lastly, as Androgen Receptor and Estrogen Receptor PROTAC degraders are being pursued as treatment for prostate cancer and breast cancer, respectively, a rationale is provided for the translational utility for the degradation of these two NRs.
Immunohistochemistry was used to evaluate the presence of CPA4, estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2, Ki67, epidermal growth factor receptor, cytokeratin 5/6, aldehyde dehydrogenase 1, cluster of differentiation (CD)44, CD24, claudins, E‑cadherin, vimentin and androgen receptor in 221 cases of breast cancer, including 68 TNBC cases.
Our analyses suggest that the heterogeneity of TNBC is at least partially associated with the presence or absence of AR expression, suggesting that QNBC should be considered as a clinically relevant BC subtype.
We have previously reported that deubiquitinase USP14 stabilizes AR proteins by deubiquitination and USP14 inhibition results in inhibition of cell growth and tumor progression in AR-positive prostate cancer and breast cancer.
The purpose of this review is to present a state of the art scenario with consideration to the most recent discoveries about miRNAs involved in the AR associated pathogenesis of BC, in order to provide new insights into the role of miRNAs as key drivers in the modulation of AR, and possible actors in the development and progression of BC.