Glioblastoma stem cell morphotypes convey distinct cell states and clinically relevant functions

Barelli, C.; Bonfanti, M.; Mirabella, F.; Ricca, D.; Alizadehmohajer, N.; Sokolova, V.; Campione, A.; Sicuri, G. M.; Peano, C.; Faletti, S.; Stefini, R.; Kalebic, N.

doi:10.1101/2025.03.24.644884

bioRxiv · 10.1101/2025.03.24.644884

Glioblastoma stem cell morphotypes convey distinct cell states and clinically relevant functions

Barelli, C.·Bonfanti, M.·Mirabella, F.·Ricca, D.·Alizadehmohajer, N.·Sokolova, V.·Campione, A.·Sicuri, G. M.·Peano, C.·Faletti, S.·Stefini, R.·Kalebic, N.

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Abstract

Glioblastoma (GBM) is an aggressive brain tumor and an unmet clinical need due to its invasiveness and therapy-resistance. These features are driven by glioblastoma stem cells (GSCs), which exhibit remarkable functional heterogeneity. However, GSC transcriptional profiling alone cannot predict clinically relevant behaviors. Here, we developed CellShape-seq, a spatial transcriptomics platform that integrates cell morphology with transcriptome. This identified three GSC morphoclasses corresponding to distinct transcriptomic states and functions: (1) nonpolar cells show differentiation and therapy sensitivity, (2) elongated cells are invasive, and (3) multipolar cells form intercellular networks. Importantly, chemoresistance is morphoclass-specific: elongated GSCs depend on YAP/TEAD1 signaling, while multipolar GSCs rely on gap junction-mediated networks. Targeting these vulnerabilities with specific inhibitors sensitized resistant GSC morphoclasses to temozolomide (TMZ) in patient-derived organoids. Our findings demonstrate that morphology provides critical insights into GSC behavior and establish a rationale for morphology-informed therapies to overcome resistance and improve outcomes in GBM. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=85 SRC="FIGDIR/small/644884v2_ufig1.gif" ALT="Figure 1"> View larger version (15K): org.highwire.dtl.DTLVardef@141e698org.highwire.dtl.DTLVardef@18a238corg.highwire.dtl.DTLVardef@23ef62org.highwire.dtl.DTLVardef@1390c07_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Barelli, C., Bonfanti, M., Mirabella, F., Ricca, D., Alizadehmohajer, N., Sokolova, V., Campione, A., Sicuri, G. M., Peano, C., Faletti, S., Stefini, R., Kalebic, N.. 2025-03-24. Glioblastoma stem cell morphotypes convey distinct cell states and clinically relevant functions. https://doi.org/10.1101/2025.03.24.644884

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