KEGG analysis revealed that various tumor-related metabolic pathways were significantly upregulated in GBM organoid, including lipid metabolism (biosynthesis of unsaturated fatty acids, steroid biosynthesis, PPAR signaling pathway), amino acid metabolism (valine leucine and isoleucine degradation), glycan metabolism (glycosphingolipid biosynthesis, heparan sulfate biosynthesis, O-glycan biosynthesis) and terpenoids metabolism (Terpenoid backbone biosynthesis) (Fig. 6c, d). This evidence concerns the gene PPARA and glioblastoma.