COL1A1 and glioblastoma: The genes enriched in U-343 MG included classical mesenchymal genes FN1, SNAI2, and COL1A1. Furthermore, U-343 MG had a high support index for mesenchymal glioblastoma subtype, calculated as previously described,3,18 compared to the U-343 MGa cell lines (Supplementary Figure S2G).