Fig. 3.

ERG activates cGMP synthesis in PCa cells in vitro and in vivo. a VCaP and LNCaP cells treated with 0, 10 or 50 μM riociguat for 24 h were subjected to the measurement of cellular cGMP level using ELISA kit. b, c VCaP cells stably infected with lentiviral shNTC or two independent shRNA against ERG (shERG-1,2) were b subjected to immunoblotting or c treated with or without riociguat (50 μM for 24 h), followed with cGMP ELISA assay. d LNCaP-tetERG cells pretreated with doxycycline for 3d and then treated with 50 μM riociguat for 24 h were subjected to cGMP ELISA assay. e Subcutaneous xenograft tumors derived from LNCaP (N = 4), CWR22-RV1 (RV1) (N = 4), or VCaP (N = 7) were established and then tumor biopsies were taken to examine the intratumoral cGMP level. f–h Equal amount of VCaP-shNTC or VCaP-shERG stable cells were subcutaneously injected into the left or right flank of the same mouse (N = 4) to allow xenograft tumor establishment. When the first xenograft reached ~1 cm in diameter, the group of mice were sacrificed and f tumor volumes were measured. Tumor biopsies from two mice were then taken for subsequent analyzes with g immunoblotting and h cGMP ELISA asay