CYP51A1 and central nervous system cancer: To test this hypothesis, we treated glioma TS cells with two different pharmacological inhibitors of the cholesterol synthesis pathway: ketoconazole, an FDA-approved antifungal that blocks the demethylation of lanosterol by CYP51A1 [39], and Ro 48-8071, which inhibits the formation of lanosterol by the oxidosqualene cyclase LSS [40] (Supplementary Figure 2).