Basal cells from primary benign human prostate tissue, with the cooperative effects of AKT, ERG, and AR, recapitulate the histological and molecular features of human prostate cancer, with loss of basal cells and expansion of luminal cells expressing PSA and alpha-methylacyl-CoA racemase in immunodeficient mice [16, 17]. The gene discussed is KLK3; the disease is prostate carcinoma.