SOX2 and cancer: Next, expression of critical oncogenic and resistance drivers in GBM, such as p53, MGMT, c-MYC, cancer stem cell markers CD133, Sox2, and metabolic regulator IMPDH2 was examined over time in response to TMZ with no significant difference except downregulated IMPDH2 and β-catenin in GBM6R (Supplementary Fig. 1A).