IGF-I-activated Pyk2 is critical for IGF-IR-dependent motility of invasive urothelial cancer cells.
(A) Serum-starved 5637 cells were stimulated with 50 ng/ml of IGF-I for the indicated time points. Pyk2 phosphorylation was detected by immunoblot using anti-phospho-Pyk2 (Tyr402) antibodies, while total Pyk2 protein level was assessed using anti-Pyk2 polyclonal antibodies. Blot is representative of two independent experiments. (B) Migration of 5637 cells transiently transfected with either Flag-tagged wild type (PYK2 WT) or a dominant negative (KD PYK2) Pyk2 proteins was assessed after 16 hours of IGF-I stimulation. Values are expressed as fold change over SFM and represent mean ± SD. ** P<0.01. (C) Expression levels of transiently transfected Pyk2 proteins were assessed by immunoblot with anti-flag M2 antibodies. Blot is representative of two independent experiments.