Functional Etk is expressed in bladder cancer cell lines.

<p><b>A</b>, Expression profile of ETK in bladder cancer cell lines. ETK expression level in total cell lysates from bladder cancer cell lines was examined by immunoblotting with anti-ETK. Tubulin was used as a loading control. <b>B</b>, Activation of ETK in bladder cancer cells treated with EGF. UM-UC-3 and T24 cells were serum starved for 24 h, then treated with 20 ng/ml EGF for 15 or 30 min. The level of activated EGFR and ETK was monitored by immunoblotting with anti-pEGFR(Y1175) and anti-pETK(Y40) respectively. The level of total EGFR and ETK in the cell lysates was also detected with anti-EGFR and anti-ETK respectively. <b>C</b>, Regulation of STAT3 and AKT activity by ETK in bladder cancer cells. UM-UC-3 and T24 cells were infected with lentivirus encoding the shRNA specific for ETK or a vector control. At 24 h post-infection, cells were serum starved overnight and then lysed. The level of active STAT3 and AKT was examined by immunoblotting with anti-pSTAT3 (Y705) and anti-pAKT (S473) respectively (Left panel). The effect of ETK overexpression on STAT3 and AKT activity was also examined in bladder cancer 5637 cells (Right panel).