AR and breast cancer: To test this, we took advantage of ChIP-seq data from Gene Expression Omnibus (GEO) for oestrogen receptor alpha (ERα or ESR1) binding in T47D breast cancer cells stimulated with the oestrogen receptor agonist bisphenol A (BPA) – 1,878 sites51 and for androgen receptor (AR) binding in PC3 prostate cancer cells stimulated with the androgen receptor agonist R1881 – 34,777 sites52.