Furthermore, there were also profound differences in the steady-state levels of several proteins implicated as therapeutic targets in GB such as glioma promoting factor TGFβ [41,42], TMZ-resistance factor MGMT [43], stemness marker CD133/Prominin-1 [44] or the marker of Proneural subtype PDFGRα [45] (Figure 5). Here, TGFB1 is linked to central nervous system cancer.