MGMT and glioblastoma: Interestingly, and in line with our observations of the importance of ZEB1, is a recent report showing that the ZEB1-mir-200 feedback loop is involved in invasion, chemoresistance and tumorigenesis in glioblastoma, regulating the expression of, among others, methylguanine methyltransferase (MGMT) and CD133.36 In addition, we also observed differences in tumor vasculature and enhanced infiltration of neutrophils in TGF-β-treated implanted U87 cells, although not consistently.