CNSC-23. CROSSTALK BETWEEN STROKE AND GLIOMA: ISCHEMIA-INDUCED NEURONAL ACTIVATION ON GLIOMA INFILTRATION

Abstract Glioblastoma (GBM) is an aggressive primary brain tumor associated with dismal survival rates. GBM is difficult to treat due to its ability to invade neighboring brain regions, rendering complete surgical resection nearly impossible. Throughout tumor progression, several pathological changes occur in the tumor microenvironment (TME) including increased neuronal hyperactivity. Interestingly, these pathological features also occur in stroke, a leading global cause of death and disease burden. Clinical evidence from large cohort studies reveals a 10% risk of brain tumor development in stroke patients, suggesting a link between these two diseases. However, the intricacies of their association and whether stroke poses a long-term risk for GBM is unclear. To investigate this, we have developed innovative stroke-glioma mouse models to recapitulate and delineate the interrelationship between these two diseases. Our data using these models indicate a substantial increase in tumor growth and infiltration towards the infarct using both human GBM-patient derived glioma cells in immunodeficient mice as well as in immunocompetent de novo mouse GBM. Further, spatial manipulation of stroke and glioma induction revealed that glioma cells preferentially invade the contralateral hemisphere towards the stroke lesion compared to control. This suggests stroke-induced changes may trigger glioma cell infiltration. Histological analysis of the TME shows increased neuronal activity specifically excitatory neuron synaptic marker expression in the leading edge of glioma post-stroke compared to control. Overall, stroke induction may promote tumor growth and infiltration by modulating the TME through increasing excitatory neuronal activation. Together, this study aims to deepen our understanding of the influence of stroke on gliomas, paving the way for invaluable insights essential for identifying at-risk patients and the development of potential treatments for affected patients.