Previously, NFIC, Sp1, Sp3, GATA-4 and -6 were shown to regulate CYP17A1 expression.24 In particular, GATA-4 and GATA6 have been reported as a tumor suppressor gene, and as a negative regulator of astrocytoma.25, 26 Therefore, we excluded GATA-4 and GATA6 initially. The gene discussed is SP1; the disease is astrocytoma (excluding glioblastoma).