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. J. Surg. Oncol. 2011; 103:768-772. (C) 2011 Wiley-Liss, Inc.