We have previously shown that the PC3-ML human prostate cancer cell line, which is ARNEG (11, 12), expresses high levels of IL1β; in contrast, all ARPOS prostate cancer cell lines we tested uniformly lacked IL1β expression, in line with the inverse AR/IL1β correlation we observed in a small cohort of 10 patients (4). This evidence concerns the gene AR and Familial prostate cancer.