The hormone receptors, such as estrogen receptor alpha and androgen receptor in breast cancer and prostate cancer, are critical to cancer cell proliferation and tumor growth.
Although AR is expressed in breast cancer and the impact of androgen and AR on breast cancer has been recognized, the role of the CAG repeats in breast cancer remains unknown.
The number of vital CETCs was determined from blood of 66 patients suffering from breast cancer and the expression of AR and ER on these cells was investigated using the maintrac method.
Together, these observations identify AR signaling in CTCs from women with bone-predominant ER<sup>+</sup> breast cancer, and provide a rationale for testing androgen inhibitors in this subset of patients.<b>Implications:</b> This study highlights a role for the AR in breast cancer bone metastasis, and suggests that therapeutic targeting of the AR may benefit patients with metastatic breast cancer.<i></i>.
Our study supports the notion that targeting AR could be effective for many BC patients and that re-testing of AR status in formerly negative or mixed type BC's is recommended.
The present findings showing frequent expression of structurally unaltered androgen receptor in an advanced stage of EMPD may provide a rational basis for hormone therapy, which is widely used in the treatment of metastatic prostate cancer and androgen receptor-positive breast cancer recurrence.
In this study AR expression was studied on a large (n = 1141) consecutive series of early-stage (I-III) BC using tissue microarray and immunohistochemistry (IHC).
Interestingly, preclinical and clinical studies have shown a critical role for the cross-talk between androgen receptor (AR) and ER in luminal-like BC.
Because AR coactivators enhance transactivation of AR, in this report we evaluated the relationship of a CAG/CAA repeat length polymorphism in the AIB1/SRC-3 gene (amplified in breast cancer gene 1, a steroid receptor coactivator and an AR coactivator) with prostate cancer risk in a population-based case-control study in China.
Androgen receptor (AR) is an attractive target in breast cancer because of its frequent expression in all the molecular subtypes, especially in estrogen receptor (ER)-positive luminal breast cancers.
We estimated the frequencies of AR alleles and found that women with two long AR alleles (≥21 CAG repeats) had an increased risk of developing breast cancer, while those with two short AR alleles (<21 CAG repeats) were likely to be normal (p = 0.00069).
Hormonal therapies in prostate and breast cancer that directly target AR and ERalpha, respectively, are then presented and possible novel drug targets in the SHR pathway are discussed.
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.
<b>Purpose:</b> Androgen receptor (AR) expression has been observed in about 70% of patients with breast cancer, but its prognostic role remains uncertain.<b>Experimental Design:</b> To assess the prognostic role of AR expression in early-stage breast cancer, we performed a meta-analysis of studies that evaluated the impact of AR at the protein and gene expression level on disease-free survival (DFS) and/or overall survival (OS).
Our data suggest a role for AR overexpression as a novel mechanism of hormone resistance, so that AR may offer a new clinical therapeutic target in human breast cancers.