Luminal BC subtypes express the protein of luminal epithelial cells, called the ‘‘luminal group”, such as luminal cytokeratins (CK8 and 18), ER and GATA3; BLBCs express high molecular weight basal cytokeratins (CK5/6, 14, and 17) and EGFR and/or c-KIT [30]. The gene discussed is KRT5; the disease is breast cancer.