ENPEP and breast cancer: Moreover, overexpression of subset of genes was found to be associated with breast cancer tumorigenesis (ID4, SOX5, ITM2A, SNCG, EPHA4, NTS, CYP1B1, FGFR2, ENPEP), whereas ID4, SEMA3F, FOXD, KCNK5, WNK4 and ECM1 genes may play a role in the chemoresistance of cancer cells.