NR4A1 and breast cancer: The effects of these NR4A1 ligands and NR4A1-dependent transactivation were determined in MDA-MB-231 breast cancer cells transfected with constructs containing a yeast GAL4-NR4A1 chimera and a UAS-luc reporter gene (containing five GAL4 response elements) (Figure 2A) and an NBRE-luc construct containing a monomeric NBRE site that binds monomeric NR4A (Figure 2B).