Virus yields in prostate cancer cells and spheres. (A) The virus yield in DU145 cells was significantly higher than those in other cells. Spheres are designated DU145S, PC-3S, WPE-intS, and C4-2BS. (B) PSA induction using the synthetic androgen analog R1881 significantly increased virus replication in AR+ cells (C4-2B and WPE-int) and decreased virus yield in AR+ spheres (C4-2BS and WPE-intS), *, P < 0.0001; n = 8. (C) Multistep growth kinetics of BC-KLQL-GFP, at an MOI of 1, after PSA induction with R1881 (1 nm/ml).