NR4A1 and breast cancer: Conversely, in human triple-negative breast cancer the NR4A1 expression was negatively correlated with tumor stage, lymph node metastasis and disease recurrence, and in mouse models of basal-like mammary tumors a progressive NR4A1 reduction has been found during cancer development (Nuclear receptor NR4A1 is a tumor suppressor down-regulated in triple-negative breast cancer).