Abstract Glioblastoma (GBM) is the most common malignancy of the central nervous system, characterized by a dismal prognosis and inevitable recurrence despite aggressive standard-of-care therapy. Extensive colonization of the surrounding brain parenchyma precludes complete surgical resection, posing a significant therapeutic challenge. While well-studied in model systems, the molecular features and epigenetic regulators of invasive GBM cells remain under-explored directly in clinical samples. To address this gap, we performed a multimodal single-cell sequencing characterization of GBM tumor samples from anatomically distinct regions collected using MRI guidance. Our results demonstrate an enrichment of progenitor-like (neural- and oligodendrocyte-like) malignant states and neurons at the tumor margins. In contrast, differentiated-like states and myeloid cells were more abundant in the tumor core. Peri-tumoral progenitor-like malignant states expressed a unique neuronal signature associated with synaptic signaling, neurogenesis, and Notch signaling. Further, the expression of this neuronal signature was correlated with increased invasiveness. Analysis of matched primary-recurrent GBM patient cohorts revealed an expansion of this neuronal activity program, which was associated with worse overall survival. Motifs of proneural transcription factors implicated in neuronal lineage differentiation were also found to be differentially accessible in progenitor-like malignant states marked by the neuronal invasive signature, potentially contributing to the remodeling of cell states at the invasive margin. Further, cell-cell interaction analysis predicted greater communication between neurons and peri-tumoral progenitor-like malignant states, mediated predominantly through neurexin-neuroligin trans-synaptic signaling, facilitating synaptogenesis and the integration of tumor cells into neural circuits. Altogether, these findings suggest a model in which GBM invasive cells communicate with normal brain neurons in peri-tumoral regions, exploiting neurodevelopmental pathways to facilitate invasion and potentially seed recurrence. Our characterization of invasive GBM cells provides insight into the mechanisms of brain invasion and highlights potential therapeutic vulnerabilities of malignant invasive cells. Understanding these mechanisms opens new avenues for targeted therapies aimed at curtailing the invasive and adaptive capabilities of GBM.
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