For example, VEGFR1 and VEGFR2 are believed to be critical factors in glioblastoma progression, and VEGF overexpression can promote abnormal vascular proliferation in glioblastoma multiforme (GBM) by binding to its receptors VEGFR1 and VEGFR2 [7, 8]. Here, FLT1 is linked to glioblastoma.