BRD4 and prostate cancer: This compound is an orally bioavailable degrader of the androgen receptor (AR), developed to treat metastatic castration‐resistant prostate cancer.[20] Additionally, there has been significant interest from the scientific community in the development of PROTACs that target epigenetic proteins, particularly bromodomain and extra‐terminal (BET) proteins (BET), for example, bromodomain‐containing protein 4 (BRD4),[21] and non‐BET proteins, for example, bromodomain‐containing protein 9 (BRD9).