Antitumor Effects of Exogenous Ganglioside GM3 on Bladder Cancer in an Orthotopic Cancer Model

OBJECTIVE To investigate the therapeutic effects of exogenous gangliosides GM3 on human bladder cancer cell lines and the severe combined immunodeficiency mouse model of orthotopic bladder cancer. MATERIALS AND METHODS Human bladder cancer cell lines YTS- 1, T24, 5637, and KK47 were used in the study. In vitro cytotoxicity of GM3 was assessed using the cell counting kit- 8. Cell adhesion was determined using a spreading assay. Phosphorylation of epidermal growth factor receptor was determined by Western blotting. In vivo, the orthotopic bladder cancer model was established using severe combined immunodeficiency mice and GM3 was administered intravesically by way of a transurethral catheter. RESULTS GM3 inhibited the proliferation of all the bladder cancer cell lines tested. The addition of GM3 decreased cell adhesion and epidermal growth factor- dependent phosphorylation of epidermal growth factor receptor. Direct instillation of GM3 into the bladder of the orthotopic model significantly inhibited tumor growth. CONCLUSION Our results suggest exogenous GM3 as a potential therapeutic agent for treating bladder cancer. UROLOGY 81:210.e11-e210. fe15, 2013. (C) 2013 Elsevier Inc.