Androgen receptor variants confer castration resistance in prostate cancer by counteracting antiandrogen-induced ferroptosis

• Published in: Cancer research (Chicago, Ill.) Ill.), 2023-10, Vol.83 (19), p.3192-3204
• Main Authors: Sun, Rui, Yan, Binyuan, Li, Hao, Ding, Donglin, Wang, Liguo, Pang, Jun, Ye, Dingwei, Huang, Haojie
• Format: Article
• Language: English
• Subjects: Cancer Biology
• ISSN: 0008-5472; 1538-7445
• DOI: 10.1158/0008-5472.CAN-23-0285

Androgen receptor (AR) inhibition by androgen deprivation and/or antiandrogen administration is the mainstay therapy for advanced prostate cancer (PCa). However, most prostate cancers ultimately become resistant to these therapies, indicating the importance of identifying mechanisms driving resistance to improve patient outcomes. Here we demonstrated that acute treatment with the antiandrogen enzalutamide (ENZ) decreased glutathione (GSH) production, increased lipid peroxidation, and induced ferroptosis in PCa cells. Consistently, meta-analysis of transcriptomic data linked the androgen-AR axis to metabolism-related biological processes, including lipid metabolism. The cystine transporter gene SLC7A11 was a key AR target, and full-length AR (AR-FL) transactivated SLC7A11 transcription by directly occupying the SLC7A11 promoter and putative enhancer regions. AR variants (AR-Vs) preferentially bound the SLC7A11 enhancer and upregulated SLC7A11 expression, thereby conferring resistance to ferroptosis induced by ENZ treatment. However, this effect was abolished following downregulation of AR-Vs using the dual CBP/p300 and BET inhibitor NEO2734. These findings reveal ferroptosis induction as an anti-cancer mechanism of antiandrogens and SLC7A11 as a direct target gene of AR-FL and AR-Vs. AR-V-mediated SLC7A11 expression represents a mechanism coupling ferroptosis resistance to PCa progression.