The UT antagonist/biased ligand urantide and the non-peptide UT antagonist palosuran prevented UII-induced tubulogenesis in vitro and significantly delayed tumor growth in vivo. Urantide drastically prevented UII-induced GBM angiogenesis, MMP-2 and MMP-9 expression, and integrin activation associated with GBM growth. Here, MMP9 is linked to glioblastoma.