TGFB1 and central nervous system cancer: To characterize how anti‐VEGFR and anti‐TGFβ1 treatments can normalize brain tumor vasculatures and ECM, respectively, we treated C57BL/6 mice orthotopically implanted with GL261 glioma with isotype‐matched IgG, a rat anti‐VEGFR‐2 antibody (DC101; 10 mg kg−1 every 3 days), or a murine anti‐TGFβ1 antibody (100 μg every 3 days) (Figure2a).