Figure 4.

Knockdown of CRK reduces c-Met activation through impaired hepatocyte growth factor (HGF) production and a decline in Gab1 phosphorylation. (a,b) In 5637 and UM-UC-3 BC cells with or without CRK depletion, levels of the expression and phosphorylation (p-) of indicated proteins were analyzed by immuno-blotting. †Suppression of phosphorylation levels in CRK knockdown cells. (c) Total RNA was isolated from indicated cell lines, and endogenous expression level of HGF mRNA was examined by real-time RT-PCR. **P < 0.01 versus control cells (empty). EGFR, epidermal growth factor receptor; PDGFRα, platelet-derived growth factor receptor-α; SMAD2,