As cancer cells, including prostate cancer cells and migratory glioma cells, have also been shown to express DCX,54,55 we first assessed DCX expression in normal (benign) mammary tissue (n = 3 cases with no concurrent cancer) with IHC staining for DCX, and found no DCX expression in normal mammary epithelium (Supplementary Fig. S5). This evidence concerns the gene DCX and cancer.