Fig. 3
PDGF is critical for glioma-CM-induced VEGFR-2 down-expression and EC resistance to anti-VEGF treatment. a, b Human brain microvascular ECs were treated with glioma-CM in the absence or presence of anti-PDGF-AA or anti-PDGF-BB neutralizing antibody or control IgG. a Cell lysates were immunoblotted. b RNA was isolated and analyzed by RT-PCR. Results were normalized with GAPDH levels (n = 3–5, mean ± SD). c Normal brain ECs were transfected with siRNAs targeting PDGFR-α, PDGFR-β, or control scrambled sequence, and treated with glioma-CM. Cell lysates were immunoblotted. d Human brain ECs were pretreated with 100 ng/ml PDGF-AB or PDGF-BB, followed by treatment with 3 nM Ki8751. Cell proliferation was determined (n = 3, mean ± SD). P values were determined by Student’s t test
