Unveiling Oligodendrocyte-Lineage Differentiation in the Glioblastoma Infiltrative Zone Through Spatial Transcriptomics
IDH-wildtype glioblastoma (GBM) is the most aggressive primary brain tumor, characterized by limited therapeutic options and inevitable recurrence. This recurrence is driven by the highly infiltrative behavior of GBM cells, which prevents complete resection. Here, we performed spatially resolved transcriptomic profiling of four surgically defined GBM regions to characterize the infiltrative tumor compartment. Across multiple datasets and profiling approaches, the infiltrative zone showed reduced cellular heterogeneity compared with the tumor core. By comparison with an integrated reference of single-cell RNA sequencing data, we revealed that this reduction reflects a preferential differentiation of infiltrative GBM cells toward an oligodendrocyte-like lineage, accompanied by attenuated inflammatory signaling. In contrast, necrotic and proliferative regions display pronounced astrocyte-like and mesenchymal-like programs. Combined immunohistochemistry and fluorescence in situ hybridization confirmed the enrichment of oligodendrocyte-like tumor cells in the infiltrative area. Together, these findings identify the oligodendrocyte-like state as a defining feature and potential therapeutic vulnerability of infiltrative GBM driving brain invasion and relapse.