The cell lines CWR-R1-enzalutamide resistant/luciferase+ (stably expressing a firefly luciferase), and CWR-R1-enzalutamide resistant/luciferase plus FAP (additionally expressing a human FAP receptor) were provided by the LeBeau lab from the University of Wisconsin (28 (link)). Both cell lines and 293AAV cells (Cell Biolabs) were cultured in DMEM (Gibco) supplemented with 10 % fetal bovine serum (Gibco), 4.5 g/L D-glucose, L-glutamine, 110 mg/L sodium pyruvate, and 100 U per mL penicillin/100 μg per mL streptomycin (Gibco). Media for R1-FAP cells was additionally supplemented with 3 μg/mL puromycin (ApexBio Technology). Cells were kept in a humidified incubator at 37 °C and 5 % CO2 and passaged every 2-4 days when reaching a confluency of 70-80 %.