Jennifer L Bishop 1 , Daksh Thaper 1 , 2 , Sepideh Vahid 1 , 2 , Alastair Davies 1 , Kirsi Ketola 1 , Hidetoshi Kuruma 1 , Randy Jama 1 , Ka Mun Nip 1 , 2 , Arkhjamil Angeles 1 , Fraser Johnson 1 , Alexander W Wyatt 1 , 2 , Ladan Fazli 1 , 2 , Martin E Gleave 1 , 2 , Dong Lin 1 , Mark A Rubin 3 , Colin C Collins 1 , 2 , Yuzhuo Wang 1 , 2 , Himisha Beltran 3 , Amina Zoubeidi 4 , 2
Mechanisms controlling the emergence of lethal neuroendocrine prostate cancer (NEPC), especially those that are consequences of treatment-induced suppression of the androgen receptor (AR), remain elusive. Using a unique model of AR pathway inhibitor-resistant prostate cancer, we identified AR-dependent control of the neural transcription factor BRN2 (encoded by POU3F2) as a major driver of NEPC and aggressive tumor growth, both in vitro and in vivo Mechanistic studies showed that AR directly suppresses BRN2 transcription, which is required for NEPC, and BRN2-dependent regulation of the NEPC marker SOX2. Underscoring its inverse correlation with classic AR activity in clinical samples, BRN2 expression was highest in NEPC tumors and was significantly increased in castration-resistant prostate cancer compared with adenocarcinoma, especially in patients with low serum PSA. These data reveal a novel mechanism of AR-dependent control of NEPC and suggest that targeting BRN2 is a strategy to treat or prevent neuroendocrine differentiation in prostate tumors.