[49, 50] This increased tumor cell motility coincides with altered cellular deposition of ECM components [46, 55, 57] and increased production/secretion of ECM‐degrading members of the matrix metalloproteinases MMP2, MMP3, and MMP9 [58] and cathepsin family, including cathepsin B in patient GBM cells [45, 55]. This evidence concerns the gene CTSB and glioblastoma.