Moreover, we found dysregulated levels of certain enzymes involved in SAM and transsulfuration pathways (MAT2A, MAT2B, SETMAR, CBS, and GCLC) upon EXT2 depletion, and we identified a significant correlation between EXT2 and MAT2B and AHCY in both GBM cell models and patients at the gene expression level. The gene discussed is CBS; the disease is glioblastoma.