PDGFRA and astrocytoma (excluding glioblastoma): To investigate the effects of gB on endogenous PDGFRα-mediated signaling, we used the U373 astrocytoma cell line stably expressing gB – U15 (a gift from Dr. Lenore Pereira, UCSF, [16]) as well as the parental U373 line and measured phosphorylation levels of PDGFRα in control conditions and after stimulation with PDGF-AA or gB.