Dalerba et al. [7] suggest cell surface glycoprotein CD44 and Epithelial Cell Adhesion Molecule (EpCAM) as specific markers of CR-CSCs: in the context of CD133+ tumor population, they have identified a subset of stem-like CD44+/EpCAMhigh cells able to generate tumor xenografts upon serial transplantation into NOD/SCID mice. This evidence concerns the gene PROM1 and neoplasm.