Analysis of the levels of carnitine compounds revealed lower levels of these metabolites (i.e., carnitine, propionylcarnitine, 2-methylbutyrylcarnitine, isobutyryl-L-carnitine, and deoxycarnitine) in CSF from patients with TP53-mutant versus TP53-wildtype GBM (Fig. 6). This evidence concerns the gene TP53 and glioblastoma.