Subsequently, it was reported that transplantation of as few as 100 CD133+ glioblastoma cells or 1,000 CD133+ medulloblastoma cells were sufficient for tumor formation; whereas, 105 CD133- glioblastoma cells or 5×104 CD133- medulloblastoma cells were incapable of forming tumors [93]. Here, PROM1 is linked to medulloblastoma.