It had been estimated that there were 268,600 new cases and 41,760 deaths of breast cancer worldwide in 2019 and the incidence and mortality are rapidly increasing year by year.[1] Breast cancer is a heterogeneous tumor and is different in clinical symptoms, type of pathology, hormone receptor, Herceptin receptor, prognosis, epigenetics, and response to therapy. This evidence concerns the gene NR4A1 and breast cancer.