Although the results from previous studies have been inconsistent with regard to the overall association between smoking and breast cancer risk (Hamajima et al. 2002; Terry and Rohan 2002; Johnson et al. 2011; International Agency for Research on Cancer 2012; Nagata et al. 2006), those related to hormone receptor status have also been inconsistent. Here, NR4A1 is linked to breast carcinoma.