For example, the expression of matrix metalloproteinase 2 (MMP-2) cleavage enzyme, MT1-MMP, has been positively correlated with increasing glioma malignancy grade [22], and GAM have also been shown to induce MMP-9 expression via release of transforming growth factor beta (TGF-β) [21,22]. Here, MMP2 is linked to glioma.