Figure 4.

Knocking down EphA2 expression in 827 cells inhibits in vivo tumor development and reduces expression of stem markers. (A) 827 cells expressing control vector or EphA2 shRNA were tagged with eGFP or mCherry by lentiviral infection, and analyzed by immunoblot with the indicated antibodies. (B) Co-injection of the two cell types are described as in Fig. 2. A representative brain section shows a significantly reduced tumor development by EphA2 shRNA-expressing 827 cells (Arrow heads point to the mCherry-tagged tumor cells; star indicates the background fluorescence signal common in mouse brain.) compared with control cells. (C) Silencing EphA2 expression in D456MG cells inhibit the invasion in vivo. D456MG cells were infected with lentivirus expressing control or EphA2 shRNA and then tagged with mCherry or eGFP, respectively. Immunoblot verified the knockdown. (D) Equal number of the two types of cells were mixed and injected as in Fig. 2A. Mice were sacrificed one month later and consecutive sections were prepared from each brain. Scale bars, 200 μm. The experiments were performed three times using 6 animals each group. Data from representative experiments are shown.