Peroxisome proliferator-activated receptor gamma expression in urothelial carcinomas of the bladder: Association with differentiation, proliferation and clinical outcome

AimsPeroxisome proliferator-activated receptor γ (PPARγ) is a ligand-activated transcriptional factor that regulates the transcription of various target genes. Our purpose is to investigate the clinicopathologic and prognostic significance of PPARγ expression in human urothelial bladder cancer (BUC).MethodsImmunohistochemistry was applied in 117 paraffin-embedded specimens of human BUC to detect the proteins PPARγ and Ki67. The image analysis method was used for the evaluation of the immunohistochemical staining.ResultsPPARγ protein was localized in the nuclei of the malignant cells. Its expression was inversely associated with the stage of BUCs (p < 0.001), tumor grade (p = 0.007) and the expression of the proliferation marker Ki67 (p = 0.015) while it was found to exert a favorable effect on patients’ overall survival (p = 0.001).ConclusionThe findings of the present study suggest that in BUC, PPARγ expression can identify patients with a better prognosis who suffer from more differentiated, non-invasive tumors, of a low proliferative potential.