Expression of transient receptor potential vanilloid-1 (TRPV1) in urothelial cancers of human bladder: relation to clinico-pathological and molecular parameters.

International audienceAims: The aim of this study was to evaluate the expression of transient receptor potential vanilloid type-1 chennel protein (TRPV1) in normal and tumor urothelial tissues; to correlate TRPV1 expression with clinico-pathological parameters and with disease-specific survival. Methods and Results: TRPV1 expression was analyzed in normal and tumor urothelial samples at both mRNA and protein levels by Real-Time PCR and immunohistochemistry, respectively. TRPV1 down-regulation was found in UC specimens, which correlates with tumor progression. Moreover, TRPV1 mRNA levels were associated to clinico-pathological parameters to asses the role of TRPV1 down-regulation as a negative prognostic factor for survival. Kaplan-Meier survival analysis demonstrated a significantly shorter survival in patients showing TRPV1 mRNA down-regulation. Multivariate Cox regression analysis further indicated that TRPV1 mRNA expression retained its significance as an independent risk factor. Conclusions: The progression of UC of human bladder is associated with a marked decrease of TRPV1 expression, with a progressive loss in high-grade muscle invasive UC. Down-regulation of TRPV1 mRNA expression may represent an independent negative prognostic factor for the survival probability of bladder cancer patients