Figure 4
From: Regulation of Erk1/2 activation by osteopontin in PC3 human prostate cancer cells
Osteopontin induces activation of Akt through αVβ3 integrins and CD44. Different PC3 cell lines (PC3, PC3/OPN, and PC3/RGA) were treated with and without αV integrin inhibitor (Cyclo-RGD, 10 μM for 16 h (panel A), siRNA to CD44 (200 nM for 48 hr; panels B and C), or a combination of both the αV integrin inhibitor and CD44 siRNA (panel D). The effects of inhibitors on Akt activation or phosphorylation were determined by immunoblotting analysis (upper panels, A-D). Total Akt levels were used as loading controls (lower panels in A, C, and D). Immunoblotting with a GAPDH antibody indicates equal loading in panel B. Changes in Akt phosphorylation levels were normalized to respective control on the Western blot shown in D and represented as fold change in the graph (Figure E). Graph E is a quantitative representation of the single western blot shown in panel D. Immunoblotting results are representative of three independent experiments.