Previous data showed that blockade of PI3K/AKT/SOX2 did not completely suppress glioma cell proliferation cultured in the 3D collagen/FN system and a high percentage of cells still displayed the proliferative phenotype (Figure 3D and S3D), suggesting that growth regulation of glioma by the collagen/FN system is complex. Here, AKT1 is linked to central nervous system cancer.