Figure 6.

Inhibiting GH action decreases ARv7 and IGF-1 in 22Rv1 xenografted tumors in vivo. 22Rv1 cells (1x10⁶) were subcutaneously injected in both flanks of male athymic nude mice. Once tumors reached 100 to 200 mm³ volume, mice (n = 8 per group) were treated three times a week with vehicle, 100 mg/kg pegvisomant (Peg, Pfizer), 20 mg/kg enzalutamide (Enz), or both (E+P). (a) Serum PSA levels were measured by enzyme-linked immunosorbent assay. (b) Western blot analysis of IGF-1 in liver extracts derived from control and pegvisomant-treated mice. (c) Western blot analysis of ARv7 and IGF-1 in tumor protein extracts comparing control vs pegvisomant treated mice and enzalutamide vs enzalutamide/pegvisomant treated mice. Representative blots are shown. Intensity of the bands was quantified with ImageJ software and the fold change of ARV7/β-actin or IGF-1/ β-actin is shown in the bar graphs on the right. *P < 0.05.