PTPRB and glioblastoma: As VE-PTP was detected in both GBM vessels and nontumor brain vessels and its level was unaffected by treatment with either 4E2 or DC101 (Supplementary Fig. 7g), it is unlikely that the effect of 4E2 on reducing the pVEGFR2 level is mediated by VE-PTP upregulation.