Figure 3: Enrichment of AR binding to target genes in AA PCa cells compared to CA PCa cells. (a) Representative ChIP-PCR assays in the AA PCa cell line E006AA and CA PCa cell line VCaP. ChIP DNA from AR-immunoprecipitates (AR), no antibody control (no Ab) or starting chromatin DNA (Input) was amplified using PCR with primers specific to predicted AR binding sites in the promoter regions of STAT1, RHOA, ITGB5, MAPKAPK2, CSNK2A1, and PIK3CB genes. KLK3 (PSA gene) and ACTB were used as positive and negative controls for the ChIP-PCR assays, respectively. (b) Quantification of AR enrichment on target genes in AA and CA PCa cell lines. The AR occupancies on the target genes were measured based on the percentages of ChIP-to-Input signals [% Input = (ChIP signal/Input signal)/dilution rate × 100%]. Quantification of ChIP and Input signals were calculated using the Image J program [37] from NIH. Data are represented as the mean ± SD (standard deviation) of 3–5 independent ChIP and PCR experiments. *Significantly different AR occupancies at AA versus CA target genes ( using Student’s t-test).