Western Blot Analysis of Cell Signaling

Western blot analysis was performed as previously described (20 (link)). Antibodies against p-Rb^Ser780, Rb, cyclin D1, CDK6, p-ERK1/2^{Thr202/Tyr204}, ERK1/2, p-AKT^Ser473, AKT, p-p70S6K^Thr389, p70S6K, p-FAK^Tyr925, FAK, p-SrcTyr⁴¹⁶, Src, PDGFRα, FGFR1, FGFR2, cKIT, c-Myc, p21, p-MDM2 and MDM2 were from Cell Signaling Technology, Incorporated (Danvers, MA); anti-p-CDK6^Tyr24, FGFR4 were from Santa Cruz Biotechnology, Incorporated (Dallas, TX). The antibody against CDKN2A/p16^INK4a was from Abcam (Cambridge, UK). Anti-β-actin (clone B11V08) was from BioVision (Milpitas, CA). Horseradish peroxidase-conjugated secondary antibodies and the chemiluminescence system were from Millipore (Millipore, MA). Reagents for electrophoresis and blotting analysis were from BIO-RAD Laboratories (Hercules, CA). The chemiluminescent signal was acquired by C-DiGit R Blot Scanner and the bands were quantified by Image Studio™Software, LI-COR Biotechnology (Lincoln, NE).