This demethylase co-localizes with the AR in the normal prostate as well as in prostate cancer, interacts with AR in vitro and in vivo, and stimulates AR-dependent transcription: LSD1 inhibition abrogates androgen-induced transcriptional activation and cell proliferation [30]; LSD1 forms a chromatin-associated complex with ligand-bound AR; LSD1 relieves repressive histone marks by demethylating histone H3 at lysine 9 (H3K9) (Fig. 6); and, complexes containing both p53 and LSD1 have been shown to regulate transcription in a gene-specific manner [31]. The gene discussed is AR; the disease is Familial prostate cancer.