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bioRxiv · 10.1101/2025.03.26.645511

A Single-Cell Atlas of RNA Alternative Splicing in the Glioma-Immune Ecosystem

Abstract

Single-cell analysis has refined our understanding of cellular heterogeneity in glioma, yet RNA alternative splicing (AS)--a critical layer of transcriptome regulation--remains underexplored at single-cell resolution. Here, we present a pan-glioma single-cell AS analysis in both tumor and immune cells through integrating seven SMART-seq2 datasets of human gliomas. Our analysis reveals lineage-specific AS across glioma cellular states, with the most divergent AS landscapes between mesenchymal- and neuronal-like glioma cells, exemplified by AS in TCF12 and PTBP2. Comparison between core and peripheral glioma cells highlights AS-redox co-regulation of cytoskeleton organization. Further analysis of glioma-infiltrating immune cells reveals potential isoform-level regulation of protein glycosylation in regulatory T cells and a link between MS4A7 AS in macrophages and clinical response to anti-PD-1 therapy. This study emphasizes the role of AS in glioma cellular heterogeneity, highlighting the importance of an isoform-centric approach to better understand the complex biological processes driving tumorigenesis.

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Song, X., Tiek, D., Lu, M., Yu, X., Wu, R., Walker, M., He, Q., Sisbarro, D., Hu, B., Cheng, S.-Y.. 2025-03-30. A Single-Cell Atlas of RNA Alternative Splicing in the Glioma-Immune Ecosystem. https://doi.org/10.1101/2025.03.26.645511

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