Androgens are a prequisite for the development of human prostate and prostate cancer. Androgen action is mediated via androgen receptor. Androgen ablation therapy is used for the treatment of metastasized prostate cancer. The aim of the study was to identify genes differentially expressed in benign human prostate, prostate cancer and in prostate tissue three days after castration. These genes are potential diagnostic and therapeutic targets for prostate cancer and benign prostatic hyperplasia.