Effect of AR antagonist treatment on prostate cancer cell viability and tumor growth inhibition. (A) Number of live cells as a percentage of control treatment. Each data point represents the mean of at least three independent assays performed in duplicates. Bars represent standard deviation of the mean (SEM). * P < 0.05; ** P < 0.01; *** P < 0.001 (two-way ANOVA, GraphPad Prism). (B) Tumor Growth Inhibition (TGI) and PSA inhibition obtained from VCaP xenograft SCID mice treated for 3 months with Compounds 26 and 30. Tumor volume: The differences between both compound-treated groups and vehicle-treated control were statistically significant from Day 49 of treatment onward [Compound 30: *** P < 0.001 for all measurements; Compound 26: ## P < 0.01 at day 53 and ### P < 0.001 for the rest of the measurements). PSA levels: Compound 30-treated group was significantly different (*** P < 0.001) from vehicle-treated control on Days 74, 83 and 89; Compound 26-treated group was significantly different (### P < 0.001) from vehicle-treated control on Days 74, 83 and 90 (two-way ANOVA, GraphPad Prism).