NDRG2 and breast cancer: Next, classifying data of The Cancer Genome Atlas (TCGA) by intrinsic breast cancer subtypes based on PAM50 classification [3] we verified an increased downregulation of NDRG2 mRNA in luminal A- (median FC: 6.2-fold downregulation) and luminal B-type (median FC: 9.4-fold downregulation) breast specimens (Fig 1B and 1C) with respect to normal tissue expression.