SYST-25 MICROGLIA-SECRETED LIPID SPECIES DRIVE GLIOMA INVASION

The capacity of gliomas, including GBMs, to invade and infiltrate normal brain tissues makes their complete surgical removal impossible. The most crucial survival predictor is still the extent of surgical resection, urging the need to identify treatments that block the invasive growth of glioma to improve surgical resection and overall survival. Using a combination of single-cell transcriptomics, lipidomics, and high-resolution spatial metabolomics in genetically engineered GBM mouse models, reminiscent of human disease, and validation in human GBM samples, we found that 1) tumor cells infiltrating the normal brain parenchyma associate with and activate specific pathways in microglial cells (MGs), the residential brain macrophages. In turn, MGs undergo metabolic rewiring and secrete lipid species that promote glioma invasion of the different GBM subtypes by activating distinct signaling cues. Thus, blocking the MG-tumor cell axis or metabolic MG rewiring targets several GBM types and, in combination with standard therapy, results in small circumscribed tumors that should be easier excised and lead to a substantial increase in progression-free survival in glioma patients.