Enzalutamide-resistant B7H3+ human metastatic prostate cancer cells exhibited a strong signaling signature for AR itself and its co-factors (HOXB13, FOXA1) which directly bound and transactivated the promoter and distal enhancer regions of the B7H3 gene, proposing this B7 family protein as a target for inhibitory Abs. This evidence concerns the gene AR and prostate cancer.