Fig. 5.

Comparison of gene subsets up-regulated in clinical advanced prostate tumors with those up-regulated by AR in LP50 cells independently of androgen. LP50 cells were infected with AR shRNA lentivirus or nontarget control lentivirus; 12 h after infection, the cells were grown in hormone-free media to deplete androgen. The cells were then treated for 6 h with either vehicle or R1881 (1 nm) and harvested to obtain total RNA. The mRNA profile was determined using replicate samples by Affymetrix microarray analysis. Complete knockdown of AR due to the AR shRNA lentivirus was confirmed by Western blot analysis. mRNAs that were decreased by more than or equal to 50% were identified as those induced by AR independent of hormone. In the analysis in A and B, genes found to be consistently up-regulated in 19 advanced hormone ablation-insensitive prostate tumors within a platform of approximately 10,000 annotated gene probes [Tomlins et al. (43)] were used. A subset of either the top 5% most consistently up-regulated genes (A) or the top 1% most consistently up-regulated genes (B) was compared with 593 genes contained in the same platform that were found to be up-regulated by AR in an androgen-independent manner in LP50 cells. C, All of the genes up-regulated by Apo-AR (i.e. genes identified by Affymetrix DNA microarray analysis of LP50 cells after AR knockdown) are compared with genes that were up-regulated in LP50 cells by a 6-h treatment with R1881 (determined by Affymetrix DNA microarray analysis). HRPC, Hormone refractory prostate cancer.