SULF1 and central nervous system cancer: A significant decrease in the EXT1 and EXT2 expression levels in gliomas was demonstrated here (Figure 2), but according to Wade et al. [22], expression of these genes is increased in glioblastoma; low expression levels of sulfatases (SULF1, SULF2) in the para-tumourous brain tissue were not changed in gliomas of different grades, which contradicts the limited published data on increased expression of SULF1 and SULF2 in brain cancer [23,24].