Moreover, a strong correlation between the GBM transcriptional subtypes and IHC profile was demonstrated, with higher expression of ASCL1, OLIG2, and PDGFRα in proneural GBMs; EGFR in classical GBM; and p53, pNDRG1, YKL40, and MET in mesenchymal GBM, which were able to predict the molecular subtypes with high efficacy using machine learning tools [27]. This evidence concerns the gene OLIG2 and glioblastoma.