Higher Expression of Peroxisome Proliferator-activated Receptor γ or Its Activation by Agonist Thiazolidinedione-rosiglitazone Promotes Bladder Cancer Cell Migration and Invasion

OBJECTIVE To investigate the role of peroxisome proliferator-activated receptor gamma (PPAR gamma) in bladder cancer (BCa) progression. MATERIALS AND METHODS The gene copy number of PPAR gamma in human BCa tissue samples was analyzed by fluorescence in situ hybridization. The migration and invasive ability of human BCa cell lines with different PPAR gamma expression levels or treated with thiazolidinedione-rosiglitazone, a PPAR gamma agonist and an antidiabetic drug, were investigated. RESULTS PPAR gamma amplification was increased dramatically in BCa tissue compared with normal urothelium (38.1% vs 4.3%, P = .0082) and in tumors with lymph node metastasis compared with those without metastasis (75.0% vs 15.4%, P = .0176). The human BCa cell line 5637 with strong PPAR gamma expression demonstrated a greater ability for cell migration and invasion than the UMUC-3 cell line with weak PPAR gamma expression. Knocking down PPAR gamma in BCa 5637 cells led to decreased cell migration, and activation of PPAR gamma with thiazolidinedione-rosiglitazone promoted their migration and invasive ability. CONCLUSION PPAR gamma amplification in BCa could play an important role in BCa cell migration and invasion. Alteration of PPAR gamma expression by PPAR gamma-small interfering ribonucleic acid or activation by its agonist rosiglitazone, a diabetic thiazolidinedione drug, could lead to alternation of BCa cell migration and invasion. UROLOGY 81:1109.e1-1109.e6, 2013. (C) 2013 Elsevier Inc.