Neuroinflammation in Alzheimer’s Disease (AD) and Glioblastoma (GBM): Shared Mechanisms and Therapeutic Insights

Introduction: Neuroinflammation is a key feature of both Alzheimer’s disease (AD) and glioblastoma, although it leads to different outcomes in each disorder. In AD, chronic activation of microglia and astrocytes by amyloid-β and tau contributes to neuronal injury and cognitive decline. In glioblastoma, tumor cells exploit inflammatory pathways to create an immunosuppressive microenvironment that supports tumor growth. This review compares the shared and distinct neuroinflammatory mechanisms in AD and glioblastoma and highlights their therapeutic relevance. Materials and Methods: This study was conducted as a narrative review based on a PubMed search performed by three reviewers. English-language articles on AD, glioblastoma, and neuroinflammatory pathways were included, covering original studies, reviews, meta-analyses, and experimental and clinical reports. Keywords included neuroinflammation, microglia, astrocytes, tumor-associated macrophages, inflammasomes, NLRP3, NF-κB, HIF-1α, cytokines, blood–brain barrier, and miRNAs. Due to study heterogeneity, findings were synthesized descriptively. Results: AD and glioblastoma share major neuroinflammatory mechanisms, including microglial and astrocytic activation, cytokine signaling, inflammasome activity, blood–brain barrier dysfunction, hypoxia-related changes, and miRNA regulation. In AD, these pathways promote chronic inflammation, synaptic loss, and neurodegeneration, with NLRP3, NF-κB, and M1-like microglial polarization playing central roles. In glioblastoma, similar pathways are redirected toward tumor progression through tumor-associated macrophages, reactive astrocytes, angiogenesis, immune evasion, and therapy resistance. Key overlapping mediators include IL-1β, TNF-α, NF-κB, HIF-1α, GSK-3β, and selected miRNAs. Conclusions: AD and glioblastoma are connected by common neuroinflammatory pathways, but these processes result in neurodegeneration in AD and tumor support in glioblastoma. Understanding these shared and divergent mechanisms may guide the development of biomarkers and targeted therapies focused on microglia, inflammasomes, cytokines, and immune reprogramming in both diseases.