FIG. 6.

Dominant-negative mutant Etk (EtkDN) blocks bombesin-induced AR pathway but not AP-1 luciferase activity. (A) LNCaP-pcDNA3, LNCaP-EtkWT, or LNCaP-EtkDN cells were cotransfected with pRL-tk vector and PSA-Luc reporter. Cells were then treated with R1881 (1 nM) or bombesin (Bomb) (100 nM) for 24 h in 5% charcoal-stripped FBS. (B) LNCaP, LNCaP-EtkWT, or LNCaP-EtkDN cells were cotransfected with pRL-tk vector and AP-1-Luc reporter (pUXLUC2X(−126/−120). Cells were then treated with EGF (10 ng/ml) or PMA (1 nM) for 24 h. The fold increase represents the ratio of the normalized luciferase activities between the cells cultured without and with EGF or PMA. The results are taken from three independent experiments.