PROM1 and neoplasm: Likewise, the incidence of tumor formation after implantation of 1000 ALDHlow/CD133+ cells (14.2%) or 1000 ALDHlow/CD133− cells (18.2%) was significantly less than ALDHhigh /CD133+ (75%) and ALDHhigh /CD133− (100%) cell populations (p = 0.04, p = 0.005 and, p = 0.007, p = 0.0002, respectively).