The different cell lines have distinct characteristics in culture and in vivo and may be used for specific research aims, so MCF-7 and BT-474 cells are ideal for investigation of hormone-receptor roles and their associated therapeutic approaches; ZR75.1 and SKBR3 cells, both HER-2 positive, might be used for testing therapies similar to trastuzumab; MDA-MB-231 and MDA-MB-436 are used for research on “triple-negative,” basal-like breast cancers [69]. Here, NR4A1 is linked to breast carcinoma.