Proteomic profiling reveals dynamic regulation of vesicle trafficking across glioma grades

Gliomas are highly heterogeneous central nervous system tumors that evolve through progressive molecular reprogramming. While cell proliferation and adhesion mechanisms are well-characterized, the contribution of vesicle trafficking to glioma progression remains underexplored. This study aimed to characterize proteomic changes across glioma grades.

We performed untargeted, quantitative proteomic profiling of glioma tissues across WHO grades I-IV using a combination of Tandem Mass Tag (TMT)-11plex labeling and high-resolution liquid chromatography-mass spectrometry (LC-MS). Tissue samples were processed using filter-aided sample preparation (FASP) and analyzed using a µPAC reverse-phase HPLC system coupled to a high-resolution mass spectrometer. Protein identification and quantification were conducted through database searching and validated against stringent quality control criteria.

We identified over 4,400 proteins across samples, revealing dynamic, grade-specific shifts in vesicle trafficking. Grade II gliomas showed upregulation of exocytic proteins (e.g., synaptotagmin, syntaxin, clathrin) and suppression of dynamin, suggesting enhanced vesicular secretion. Grade III tumors exhibited the opposite trend-marked downregulation of exocytic components with concurrent activation of clathrin-mediated endocytosis. Grade IV gliomas displayed a hybrid profile, with partial reactivation of exocytic machinery alongside sustained endocytic activity, indicative of vesicular plasticity.

This study highlights the synaptic vesicle cycle as a progressively remodeled pathway in glioma biology. Our findings suggest that vesicle trafficking is a critical, underrecognized feature of glioma pathogenesis and may represent a novel axis for therapeutic exploration.