Study identifies mechanism by which glioblastoma-derived vesicles impair cognition after radiation treatment
Researchers have found that extracellular vesicles (EVs) released by glioblastoma tumors after radiation therapy trigger cognitive impairment through a specific inflammatory signaling pathway. The study showed that these radiation-induced EVs activate the NF-κB pathway in microglia, causing the release of neurotoxic hydrogen peroxide. The findings suggest that targeting this EV-driven redox imbalance could offer a new therapeutic avenue to protect cognitive function in glioblastoma survivors.
A new preprint study on bioRxiv investigated why glioblastoma (GBM) survivors frequently experience cognitive impairment following radiation treatment, a mechanism that has remained poorly understood. The researchers found that GBM cells release extracellular vesicles after radiation therapy — termed RT-EVs — which act as intercellular messengers capable of triggering neuroinflammation. In animal models, treatment with RT-EVs was associated with measurable cognitive deficits and neuroinflammatory responses. In cell culture experiments, RT-EVs were shown to activate the NF-κB signaling pathway in microglia and induce the release of neurotoxic hydrogen peroxide (H2O2). Critically, when the NF-κB p50 subunit was knocked down, the H2O2 release was abolished, confirming mechanistic dependence on this pathway. The authors conclude that GBM-derived RT-EVs are key mediators of cognitive dysfunction through NF-κB-dependent redox dysregulation, and propose this pathway as a potential therapeutic target to reduce treatment-related cognitive side effects in GBM patients.
What's missing
As a preprint, this study has not yet undergone peer review. Key limitations include uncertainty about whether findings in animal and cell culture models will translate to human patients, and the clinical prevalence and severity of this mechanism relative to other causes of radiation-induced cognitive decline in GBM patients is also not established.
What different sources said
- bioRxivCenter
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