Biochanin-A inhibits the activity of androgen receptor mutants to suppress the development of prostate cancer

Androgen and androgen receptor (AR) were essential for the development of prostate cancer. Biochanin-A (BCA) has been reported to inhibit androgen synthesis to overcome resistance to abiraterone and enzalutamide. However, its direct function on androgen receptor remains unrevealed. Here, we investigated the affinity and biological effect of BCA to different AR mutants to find potential patients suitable for BCA treatment. Stable cell lines expressing different AR mutants in PC3 and LAPC4 cells were established. The affinity and biological effects of BCA on 12 different AR mutations were investigated by isotope competition assay, target gene expression and cell proliferation assay. The affinity of darolutamide to AR mutants were compared with enzalutamide. The inhibitory of darolutamide to AR mutants were compared with BCA. As indicated by the isotope competition experiments, BCA exhibited high affinity to AR^T877A and AR^W741C. After binding to these AR mutants, BCA suppressed the AR signaling pathway and cell proliferation of LAPC4-AR^T877A and LAPC4-AR^W741C stable cell lines. Enzalutamide and darolutamide showed different affinity to AR mutants. Darolutamide showed higher affinity to AR^W741C and inhibited AR^W741C as an antagonist. BCA not only inhibits androgen synthesis, but also directly binds to and suppresses AR^T877A and AR^W741C mutations.