IDH1 and glioma: In order to further explore specific protein expression identities and patterns that distinguish TCGA IDH-wt grade II/III glioma from GBM, we plotted the differentially expressed proteins from these datasets using an unsupervised similarity matrix clustered by sample and observed two dominant clusters; one almost exclusively contained GBM samples and the other contained predominantly IDH-wt grade II/III gliomas (Fig. 2c).