SPEAR: Spatial Epitranscriptomic Analysis by Mass Spectrometry Reveals Localized RNA Modification Remodeling During Glioma Progression

SPEAR couples laser microdissection with a redesigned LC-MS/MS pipeline to quantitatively profile dozens of RNA modifications from FFPE tissue regions as small as 0.1 mm2. In human diffuse gliomas, it resolved the transition from low-grade regions to foci undergoing malignant transformation within single specimens, revealing a coordinated decrease in multiple methylated RNA modifications in higher-grade regions, a signal masked by bulk analysis and reproducible across patients. The method establishes spatial epitranscriptomics as tractable for clinical molecular profiling and biomarker discovery.