Our results indicated that Dex loaded with a miR-21 inhibitor prolonged the survival of glioma-bearing mice by disrupting the positive feedback loop in MSCs (Fig. S7B); however, the improvement in therapeutic effect was not very significant (Fig. 6K), although the infiltration of MDSCs in glioma and CD73 expression on MDSCs were significantly decreased after miR-21 inhibitor-Dex treatment (Fig. S7C-D). This evidence concerns the gene NT5E and central nervous system cancer.