The GBM stem cell survival and the regulation of a characteristic phenotypic stem cell profile also seems to involve S1P signaling [19–21] and the sphingosine analogue FTY720 (fingolimod) slowed growth of intracranial xenograft tumors in nude mice and augmented the therapeutic effect of temozolomide [22], the standard chemotherapeutic compound for treatment of patients with GBM. The gene discussed is MBTPS1; the disease is glioblastoma.