Updated project metadata. The heterogeneous nature of glioblastoma stem-like cells (GSCs) creates hurdles in developing effective therapies against glioblastoma, making it extremely difficult to eradicate. In this part of the project, we investigated the potential role of GSCs-derived small extracellular vesicles (sEVs) in glioblastoma heterogeneity, plasticity, and aggressiveness with the particular focus on their complexity in term of proteins. Proteome profiling of sEVs and their respective cell lines showed that GSCs-derived sEVs retain their subtype characteristics and are enriched in proteins playing a role in amino acids, carboxylic acids, organic acids transmembrane transport, and growth factor binding. In summary, we revealed the protein content of GSCs-derived sEVs and unveiled their potential contribution to tumor heterogeneity and critical cellular processes commonly deregulated in glioblastoma.