FIGURE 3: Therapeutic approaches to block the growth and immunosuppressive functions of MDSCs for glioblastoma treatment. The survival and immune functions of MDSCs can be controlled by various strategies such as targeting metabolic pathways, checkpoint inhibition, depletion of MDSCs, or blocking other functions such as proliferation and migration of MDSCs into the TME in several mouse glioma models and clinical trial studies for human glioblastoma patients.