Figure 1.

Antiproliferative effects of AEE788 and expression of AEE788-sensitive targets in medulloblastoma cell lines. (A) Sensitivity to antineoplastic agents or AEE788 expressed as IC₅₀ in Daoy, cisplatinum-selected Daoy^Pt, Daoy transfected with HER2 (Daoy^HER2) or empty vector (Daoy^V), and D283 cells. Viability assays were performed after 72 hours of treatment. *P < .01, **P < .001 compared with Daoy cells (two-tailed Student's t test). (B, D) RT-qPCR analysis of expression of HER1 and HER2 (B) and VEGF and VEGFR2 (D) inmedulloblastoma lines and in the glioma lines U87 and A172. Bars show means ± SD of three determinations of each target gene normalized to the endogenous control HPRT in each sample. (C) Expression levels of total and activated HER1, HER2, and VEGFR2 in medulloblastoma cell lines. Cells were serum-starved overnight in 0.5% FBS medium, and Western blot analysis was performed to either the total or the phosphorylated levels of each protein. Equal loading was verified by actin immunoblot analysis. HUVEC cells were used as a positive control for VEGFR2 expression. No phosphorylated VEGFR2 was detected. HUVEC indicates human umbilical vein endothelial cells.