As was reported, EPCAM+ CD49f+ luminal progenitor cells were enriched for epithelial-like BCSCs while EPCAM- CD49f+ stem cells exhibited high proportion of mesenchymal-like BCSCs.Moreover, gene expression profiling indicated that epithelial-like BCSCs could be recognized by expression of ALDH+ while mesenchymal-like BCSCs could be identified via CD24- CD44+ expression in tissue, cell lines and primary xenografts of breast cancer [10]. Here, CD44 is linked to breast cancer.