Background The androgen receptor (AR) is a key prostate cancer drug target. Suppression
of AR signaling mediated by the full-length AR (AR-FL) is the therapeutic goal of all existing
AR-directed therapies. AR-targeting agents impart therapeutic benefit, but lead to AR
aberrations that underlie disease progression and therapeutic resistance. Among the AR
aberrations specific to castration-resistant prostate cancer (CRPC), AR variants (AR-Vs)
have emerged as important indicators of disease progression and therapeutic resistance …

Abstract Background Approximately 10–30% of men with mCRPC will test positive for AR-V7
using one of two analytically and clinically validated circulating tumor cell (CTC)-based
assays. These men have poor outcomes with approved AR-targeting therapies but may
retain sensitivity to chemotherapy. Here, we discuss the clinical implications of testing and
strategies that may benefit AR splice variant (AR-V)-positive men and discuss whether such
variants are passengers or drivers of aggressive clinical behavior. Methods We conducted a …