Activation of NF-kappaB in association with prostate carcinogenesis in noble rats.

There is an increasing interest in the role of chronic nonbacterial prostatitis in the development of prostate cancer. The aim of the study was to explore the role of NF-kappaB in the prostate of Noble rats treated with testosterone (T) and 17beta-estradiol (E(2)), a widely used model for prostate carcinogenesis. NF-kappaB-positive epithelial cells appeared in both inflamed and noninflamed glands and ducts at 13 weeks after hormone implantation in hypoandrogenemic, hyperestrogenemic rats. Both nuclear and cytoplasmic staining were observed. When daily dose of T was increased to give serum concentration above the level of control animals, dysplastic lesions and ductal carcinomas with NF-kappaB-positive cells were induced at 13 weeks and 26 weeks. The number of acini with NF-kappaB-positive cells decreased and no nuclear staining was observed. Surprisingly, no inflammation was seen in the periurethral region where ductal carcinomas developed. In conclusion, no unequivocal evidence was obtained to support the idea that NF-kappaB would be activated in association with inflammation in the development of ductal carcinomas. The hormonal control of NF-kappaB in the prostate warrants further studies.