Meanwhile, CD133/prominin (AC133) has been identified as a CSC marker for brain tumors including glioblastoma, ependymoma and medulloblastoma, as well as for a variety of non-nervous system tumors such as pancreatic, colon, bronchial, prostate, ovarian and liver cancer, melanoma, and leukemia [12], [13]. Here, PROM1 is linked to ependymoma.