Expression of nuclear receptor DAX-1 and androgen receptor in human breast cancer

Background The functions of nuclear receptor DAX-1 and androgen receptor (AR) in breast cancer are unknown and have not been well-characterized in terms of their importance as a predictive or a prognostic factor. The study investigated the relationship between expression of AR, DAX-1, and clinicopathological factors in primary breast cancer patients. Methods The data of 476 breast cancer patients who were treated at Seoul St. Mary's hospital from January 2004 to March 2006 were reviewed. Among them, 169 cases (35.5%) were consecutively evaluated for AR and DAX-1 expression. Results DAX-1 expression was associated with smaller tumor size; earlier disease stage; and higher expression of estrogen receptor (ER), progesterone receptor (PgR) and AR. AR was significantly expressed in patients with smaller tumor size and higher expression of ER, PgR, and DAX-1. In the subgroup analysis of triple negative breast cancer patients, the expression rate of DAX-1 (4/12, 33.3%) was higher than AR (1/12, 8.3%). Conclusions The present review revealed a very high expression rate of DAX-1 in human breast cancer (74%). DAX-1 might modify steroidogenic hormone systems like as AR, estrogen receptor, and progesterone receptor. DAX-1 might be a more effective target than AR for triple negative breast cancer.