The present application relates to treating and/or preventing prostate cancer, including metastatic and/or castrate-resistant prostate cancer, in a subject in need of treatment having particular somatic AR tumor biomarker status, comprising administering a compound of Formula (I), or a pharmaceutically acceptable salt, enantiomer, stereoisomer, solvate, polymorph, isotopic derivative, or prodrug thereof, wherein R1, R2, R3, X1, X2, X3, X4, and n are defined herein.