COL4A1 and glioblastoma: NRP1 and DAB2 have been linked to glioma progression,33,34PECAM1 correlates with GBM aggressiveness,35CD163 is positively associated with the glioma malignancy grade,36 and Flt1 promotes invasion and migration of GBM cells.37CR1, PLAGL1, COL4A1, and COL5A2 have all been shown to correlate with shorter survival.38–41