Driven by the Wnt signalling pathway, GBM stem cells often adopt mesenchymal phenotypes through the EMT process, increasing the cells’ migratory and invasive capabilities, which explains the increased expression of genes such as MMP1, MMP2, MMP9, and VEGFA that are involved in facilitating GBM invasion and the vascularisation process [43,44,45,46,47,48,49]. The gene discussed is MMP9; the disease is glioblastoma.