We found that breast cancer cells had a higher expression of epithelial markers (CLDN4, IMP3, MUC1, CDH1, CEACAM5, SCGB2A2, CLDN3 and CLDN7) that are associated with breast cancer,21 while mesothelial cell populations had a higher expression of known mesothelial markers (CALB2, WT1, UPK3B, CDH2, COL1A2, S100A4 and MSLN)21, 41, 42 (Figure 3C, ‘Epithelial’ and ‘Mesothelial’ markers). This evidence concerns the gene WT1 and breast cancer.