IDH1 and glioblastoma: In the same line, we also found significantly lower levels of Gal-1 in astrocytoma grade 4 IDH-1 mutant tumors, which had been previously described as a positive prognostic value in GBM and currently means, even in the presence of the classical histological hallmarks of GBM, a new entity in the new 2021 WHO classification of CNS tumors [5].