Furthermore, expression of both VEGFR1 and VEGFR2 has been detected on multiple rhabdomyosarcoma cell lines (i.e., RH4, RH6, RH18, RH28, RD), with the VEGFR1-positive cell lines demonstrating increased proliferation upon VEGF165 stimulation, while proliferation was halted after applying a blocking antibody against VEGFR1 [52]. Here, FLT1 is linked to rhabdomyosarcoma.