MGMT and glioma: Developed constructs were able to better mimic glioma microenvironment, which was supported by observed resistance to chemotherapeutic agents and higher expressions of tumor invasiveness markers including vascular endothelial growth factor receptor-2 (VEGFR2), matrix metalloproteinases (MMP2, MMP9) and O6-methylguanine-DNA methyltransferase (MGMT).