The involvement of signaling regulation in the cross-talk of RTKs in human bladder cancer cells. A: The UB40 cells were first pre-incubated with Src inhibitor (PP2) overnight. Then, phosphorylation status of Src, c-Met and Axl was evaluated after HGF stimulation for 10min. The PP3 (Calbiochem, Merck, Darmstadt, Germany) was used as a negative control for Src inhibition. The numbers under each band represent the relative intensity. B: After serum-starvation, UB40 and UB47 cells were treated with FTI-277 or PD98059 for 1 h, and then with HGF for 24 h. The p-ERK and levels of Ras, ERK, Axl and PDGFR-α expression were measured using specific antibodies by Western blotting. β-actin was used as an internal control. M: Mock transfection control.