These results were corroborated by assessing AR/IL1β protein expression by IHC in two prostate patient-derived xenografts (PDX), LUCaP 145.2 (ARNEG) and LUCaP 77 (ARPOS; ref. 28), and nine bone specimens from patients with metastatic prostate cancer either treatment-naïve (patient 0191) or exposed to ADT/ARIs. Here, IL1B is linked to metastatic prostate carcinoma.