CYP46A1 and glioblastoma: Nygren et al showed up to 100-fold increase in the concentration of cholesterol ester, the transport form of cholesterol, in tumor-tissue and surrounding areas compared to control tissues.[46] This could explain why mRNA expression of CYP46A1, the enzyme that coverts cholesterol to oxysterol, was also lower in GBM than in LGG in our study.