ERBB2 and breast cancer: In more detail, we revealed a pronounced downregulation of NDRG2 mRNA in luminal A- (median FC: 5.7-fold downregulation) and luminal B-type (median FC: 5.6-fold downregulation) breast cancer compared to triple negative (i.e. mammary tumors that lack receptors for estrogen (ER), progesterone (PR), and human epidermal growth factor receptor 2 (HER2)) (median FC: 3.8-fold downregulation) cases (Fig 1A).