NR4A1 and breast carcinoma: Although this subgroup consisted of only 13 patients, this is in line with previous reports.[14] Recently, we have shown that a pre-operative short course exposure to tamoxifen or anastrazole can induce a downregulation in IGF-1R expression in patients with primary hormone receptor positive breast cancer.[12] This down-regulation in IGF-1R may reflect response to endocrine therapy, since IGF-1R expression is regulated by estrogen, which can potentially explain the prolonged survival in these patients.