The luminal A condition (ER+, PR+/-, and HER2-), a subtype of breast cancer, is represented by the MCF-7, T47D, and SUM185 cell lines, whereas the luminal B condition (ER+, PR+/-, and HER2+) is demonstrated by the BTB74 and ZR-75 cell lines. This evidence concerns the gene ERBB2 and breast cancer.