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155 The expression of the receptor of hyaluronan mediated motility (RHAMM) is associated with reduced disease-specific survival in patients with bladder cancer
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The expression of the receptor of hyaluronan mediated motility (RHAMM) is associated with reduced disease-specific survival in patients with bladder cancer Eur Urol Suppl 2013;12;e155
Niedworok C.1, Kretschmer I.2, Vom Dorp F.1, Szarvas T.1, Heß J.1, Freudenberger T.2, Melchior-Becker A.2, Fischer J.W.2, Rübben H.1 1
Essen Universitiy, Dept. of Urology and Pediatric Urology, Essen, Germany, 2Duesseldorf Universitiy, Dept. of
Pharmacology and Clinical Pharmacology, Düsseldorf, Germany INTRODUCTION & OBJECTIVES: Hyaluronan (HA) is a carbohydrate of the extracellular matrix that has been attributed tumor promoting effects in a variety of cancers. The present study addressed the role of HA matrix for progression and prognosis of human bladder cancer (BC) by studying the expression and function of effector molecules of the HA matrix in human tumor tissue samples. MATERIAL & METHODS: Tissue samples of 120 patients with different stages of bladder cancer, who underwent transurethral resection or open surgery for bladder cancer at the University Hospital of Essen were analyzed. The mRNA-expression levels of HA synthases (HAS1-3) and HA-receptors (RHAMM and CD44) were evaluated by RT-rtPCR in comparison to healthy bladder tissue as control. In uni- and multivariate cox proportional hazard survival regression analysis, the impact of the gene expression levels on survival was assessed. mRNA expression data was reconfirmed in an in vitro knock-down of RHAMM by lentiviral shRNA transfection of high malignant J82 BC cells. The transfected cells were analyzed in vitro with regard to proliferation and in vivo with regard to tumor progression in a heterotopic xenograft mouse-model (nu/nu mice). RESULTS: In invasive compared to superficial tumor stages RHAMM-, HAS1 and HAS2 mRNA-expression levels were elevated whereas HAS3v1 was reduced. Subsequently, Kaplan-Meier analysis revealed reduced BC specific survival in patients with high RHAMM mRNA and low HAS3v1 expression (p<0,001). Elevated RHAMM in invasive tumors was confirmed by RHAMM immunohistochemistry (RHAMM positive staining: non-inv 3,3%(0-12,3%), inv 21,6%(3,0-27,6%), p=0,0303). Furthermore multivariate analysis revealed that only RHAMM expression was associated with poor prognosis independent from further survival factors (HR=2.389, 95% CI 1.227-4.651, p=0.010).Therefore, lentiviral RHAMM knock-down was employed and revealed reduced BC cell proliferation in vitro and reduced xenograft tumor growth in nude mice in vivo (in-vitro: shRHAMM 0,94x, ctrl 1,54x, p=0,0459; in vivo: shRHAMM 450cmm ±188,2, ctrl 711,5cmm ±201,2, p<0,001). CONCLUSIONS: The data suggest that RHAMM plays a crucial role in mediating the tumor promoting effects of HArich matrix in muscle invasive BC and recommends RHAMM for further evaluation as a prognostic marker or therapeutic target in BC therapy.
The expression of the receptor of hyaluronan mediated motility (RHAMM) is associated with reduced disease-specific survival in patients with bladder cancer Eur Urol Suppl 2013;12;e155
Niedworok C.1, Kretschmer I.2, Vom Dorp F.1, Szarvas T.1, Heß J.1, Freudenberger T.2, Melchior-Becker A.2, Fischer J.W.2, Rübben H.1 1
Essen Universitiy, Dept. of Urology and Pediatric Urology, Essen, Germany, 2Duesseldorf Universitiy, Dept. of
Pharmacology and Clinical Pharmacology, Düsseldorf, Germany INTRODUCTION & OBJECTIVES: Hyaluronan (HA) is a carbohydrate of the extracellular matrix that has been attributed tumor promoting effects in a variety of cancers. The present study addressed the role of HA matrix for progression and prognosis of human bladder cancer (BC) by studying the expression and function of effector molecules of the HA matrix in human tumor tissue samples. MATERIAL & METHODS: Tissue samples of 120 patients with different stages of bladder cancer, who underwent transurethral resection or open surgery for bladder cancer at the University Hospital of Essen were analyzed. The mRNA-expression levels of HA synthases (HAS1-3) and HA-receptors (RHAMM and CD44) were evaluated by RT-rtPCR in comparison to healthy bladder tissue as control. In uni- and multivariate cox proportional hazard survival regression analysis, the impact of the gene expression levels on survival was assessed. mRNA expression data was reconfirmed in an in vitro knock-down of RHAMM by lentiviral shRNA transfection of high malignant J82 BC cells. The transfected cells were analyzed in vitro with regard to proliferation and in vivo with regard to tumor progression in a heterotopic xenograft mouse-model (nu/nu mice). RESULTS: In invasive compared to superficial tumor stages RHAMM-, HAS1 and HAS2 mRNA-expression levels were elevated whereas HAS3v1 was reduced. Subsequently, Kaplan-Meier analysis revealed reduced BC specific survival in patients with high RHAMM mRNA and low HAS3v1 expression (p<0,001). Elevated RHAMM in invasive tumors was confirmed by RHAMM immunohistochemistry (RHAMM positive staining: non-inv 3,3%(0-12,3%), inv 21,6%(3,0-27,6%), p=0,0303). Furthermore multivariate analysis revealed that only RHAMM expression was associated with poor prognosis independent from further survival factors (HR=2.389, 95% CI 1.227-4.651, p=0.010).Therefore, lentiviral RHAMM knock-down was employed and revealed reduced BC cell proliferation in vitro and reduced xenograft tumor growth in nude mice in vivo (in-vitro: shRHAMM 0,94x, ctrl 1,54x, p=0,0459; in vivo: shRHAMM 450cmm ±188,2, ctrl 711,5cmm ±201,2, p<0,001). CONCLUSIONS: The data suggest that RHAMM plays a crucial role in mediating the tumor promoting effects of HArich matrix in muscle invasive BC and recommends RHAMM for further evaluation as a prognostic marker or therapeutic target in BC therapy.