Glioblastoma immunotherapy adjuvantsfor glial cell polarization reprogramming

Glioblastoma (GBM) remains uniformly fatal despite maximal surgical resection, temozolomide chemotherapy, and radiotherapy. Within the GBM microenvironment, tumor-educated microglia and astrocytes adopt immunosuppressive M2-like and A2 phenotypes, respectively, which shield GBM cells from adaptive immune attack. In this review, we examine emerging adjuvant strategies designed to molecularly reprogram glial cells toward proinflammatory M1/A1 states, amplifying antitumor immunity. First, we summarize key aspects of GBM pathobiology and identify why conventional treatments fail to achieve durable control. Next, we dissect the signaling networks that govern glial phase states, including NF-κB, STAT3, IRF3, NLRP3, and cGAS–STING axes. We then provide a mechanism-centric analysis of pattern-recognition receptor (PRR) agonists, inflammasome modulators, and cyclic-dinucleotide STING agonists, integrating quantitative preclinical data with early clinical trial results. For each adjuvant, we distinguish between direct astrocytic engagement and indirect cytokine-mediated reprogramming. Modulation of glial phase states holds considerable promise for enhancing personalized vaccine efficacy and for converting immunologically “cold” GBM into a T cell–inflamed tumor. Consequently, targeting glial cell phase modulation is a highly attractive strategy for GBM immunotherapy, with the potential to maximize therapeutic benefit. Despite increasing interest in cancer immunotherapy, GBM remains one of the most challenging malignancies to treat due to its uniquely immunosuppressive brain microenvironment. While chemotherapy, radiotherapy, and checkpoint inhibitors have revolutionized treatment of GBM, these strategies have had limited success largely due to failure to control immunological memory and the dominant role of glial cells in immune evasion. Astrocytes and microglia in the GBM microenvironment undergo tumor-induced polarization toward immunosuppressive phenotypes, forming a barrier to effective T cell–mediated antitumor responses. Recent studies suggest that molecularly reprogramming glial cells toward proinflammatory states could recondition the tumor microenvironment (TME), enabling more effective immunotherapy. This review explores glial phase reprogramming as an emerging immunoadjuvant strategy with a focus on key molecular circuits, synthetic modulators, and translational implications.