PROM1 and teratoma: Indeed, implantation of isolated CD133+ stem cell populations from infantile hemangiomas produce hemangioma-like tumors in xenograft animal models [14], however Oct4 and Nanog positive subpopulations from infantile hemangiomas failed to form teratomas in SCID/NOD mice [11], a hallmark of embryonic stem cell-derived tumors [15], suggesting they do not function like true embryonic stem cells.