Anastrozole (1 mg o.d.)and letrozole (2.5 mg o.d.)were compared as second-line treatment for advanced breast cancer with hormone receptor-positive or unknown receptor status in postmenopausal women who had progressed on tamoxifen in a multicentre, open-label, randomised Phase III–IV study (Rose et al, 2002). Here, NR4A1 is linked to breast carcinoma.