FIGURE 1 from Integrin-αvβ3 is a Therapeutically Targetable Fundamental Factor in Medulloblastoma Tumorigenicity and Radioresistance

Integrin-αvβ3 is differentially expressed in medulloblastoma cell lines and promotes their proliferation, migration, and invasion. A, IHC staining of integrin-αvβ3 in human medulloblastomas using tissue array slides (US Biomax, n = 20). Staining intensity was classified as no, low, or moderate expression. B, A heat map showing integrin gene expression in medulloblastoma cell lines quantified by qRT-PCR. Results are expressed in comparison to normal cerebellum (log₁₀-fold change). The mean values of three independent experiments are shown. C, A Western blot analysis of β3-integrin protein expression in medulloblastoma cell lines. D and E, Representative Western blots of β3-integrin expression in DAOY (control vs. KO and β3-integrin–overexpressing cells) and HD-MB03 (LacZ vs. β3-integrin–overexpressing cells) cell lines. Three independent experiments were performed. The proliferation of DAOY_Control, KO_#22, KO_#22-rescue (F, left), KO_#36, KO_#36-rescue (F, right), and HD-MB03-LacZ and overexpressing-β3-integrin (G). Proliferation rates represent the percentage change versus day 0. Three independent experiments were performed, and data are presented as mean ± SEM. The migration of DAOY_Control, KO_#22, KO_#22-rescue (H, left), KO_#36, KO_#36-rescue (H, right), and HD-MB03-LacZ and overexpressing-β3-integrin (I). Serum-starved cells were allowed to migrate for 12 (DAOY) or 24 hours (HD-MB03). Migrations were performed using Boyden chamber assays, and the results are presented as the percentage of control cells. Three independent experiments were performed, and data are expressed as mean ± SEM. The invasion of DAOY_Control, KO_#22, KO_#22-rescue (J, left), KO_#36, KO_#36-rescue (J, right), and HD-MB03-LacZ and overexpressing-β3-integrin (K). Serum-starved cells were allowed to invade for 12 (DAOY) or 24 hours (HD-MB03). Invasions were performed in a Boyden chamber coated with Matrigel, and results are presented as the percentage of control cells. Three independent experiments were performed, and data are presented as mean ± SEM. Key: *, P < 0.05; **, P < 0.01; ***, P < 0.001 versus control; ^##, P < 0.01 versus KO_cells.