It is significant to note that the positive correlation of IL13Rα2 expression with average mesenchymal signature gene expression and the negative correlation with proneural signature gene expression is consistent across two independent studies that defined GBM subtypes based on different criteria — patient survival for Phillips et al. [6] and unsupervised clustering for Verhaak et al. [5] — and our findings are similar for both studies despite the relatively small number of genes common to both subtype-defining signature gene sets. Here, IL13RA2 is linked to glioblastoma.