Mesenchymal Stem Cells, As Glioma Exosomal Immunosuppressive Signal Multipliers, Enhance MDSCs Immunosuppressive Activity through the miR-21/SP1/DNMT1 Positive Feedback Loop

The authors found that glioma-associated-MSCs promoted the expression of CD73, an ectonucleotidase that drove immunosuppressive microenvironment maintenance by generating adenosine, on myeloid-derived suppressor cells through immunosuppressive exosomal miR-21 signaling.