The androgen receptor (AR), also known as NR3C4 (nuclear receptor subfamily 3, group C, member 4), is a type of nuclear receptor that is activated by binding either of the androgenic hormones, testosterone, or dihydrotestosterone in the cytoplasm and then translocating into the nucleus. The main function of the androgen receptor is as a DNA-binding transcription factor that regulates gene expression. The AR is important for therapeutic target in prostate cancer, thus many different inhibitors have been developed, primarily targeting the ligand binding domain of the protein, while inhibitors that target the N-terminal domain of the protein are still under development. Description source: [Wikipedia](https://en.wikipedia.org/wiki/Androgen_receptor)