It has also been noted that HIF-2α and its target genes, including Oct-3/4, SerpinB9, GLUT-1 and VEGF were preferentially expressed in CD133+ GSCs from glioblastoma surgical biopsy specimens or xenografts derived from brain tumour specimens as compared with CD133− tumour cells under hypoxic conditions [127]. The gene discussed is EPAS1; the disease is glioblastoma.