AR and Familial prostate cancer: HOXB13 is a homeobox transcription factor involved in prostate development and displays context-dependent roles in PCa: it can act as a collaborator or a negative regulator of AR signaling43,81, it cooperates with the AR-V7 splice variant found in a subset of CRPC-Adeno82, and germline gain-of-function G84E HOXB13 mutations are associated with increased prostate cancer risk83.