Inflammation induced by lipopolysaccharide advanced androgen receptor expression and epithelial-mesenchymal transition progress in prostatitis and prostate cancer

BACKGROUND: To explore the mechanism of prostatic inflammation on prostate cancer (PCa) by comparing the changes of prostate epithelial cells and PCa cells in an inflammatory environment. METHODS: First, immunohistochemistry (IHC) was used to compare the level of expression of TNF-α, IL-1β, IL-6, and TGF-β between benign prostatic hyperplasia (BPH), prostatitis, and PCa. Then primary prostate epithelial cells were sampled from patients who were suspected of PCa and had histological prostatitis (HP) confirmed by pathological biopsy. Lipopolysaccharide (LPS) or BAY11-7082 were used to investigate the change of androgen receptor (AR) and AR-mediated transcription, epithelial-mesenchymal transition (EMT) in primary prostate epithelial cells, and lymph node carcinoma of the prostate (LNCap) cells. RESULTS: TNF-α, IL-1β, IL-6, and TGF-β were significantly increased in HP and PCa compared with those in BPH patients. The proliferation of primary prostate epithelial cells and LNCap cells got the inflection point at LPS 10 µg/mL. In an inflammatory environment with 10 µg/mL LPS, both primary prostate epithelial cell and LNCap cell viability increased, and AR, AR-mediated transcription, and EMT processes were significantly increased. Inhibitors of NF-κB with 10 nM BAY11-7082 decreased AR, AR-mediated transcription, and EMT processes. CONCLUSIONS: NF-κB regulates AR expression and EMT in prostatitis and PCa, and NF-κB inhibitors may have potential therapeutic value.