Huachansu Suppresses Human Bladder Cancer Cell Growth Through The Fas/Fasl And TNF-alpha/TNFR1 Pathway In Vitro And In Vivo

Background: Huachansu(HCS),a kind of toxic steroids extracted from the toad venom,which has been shown to be avaluable anticancer drug in many kinds of cancers.However,the effect of HCS on bladder cancer has not beenelucidated.In this study,we focused on the antitumor activities and related molecular mechanisms of HCS on bladder cancerin vitro and in vivo.Methods: Cell viability of T24,EJ,RT-4,SV-HUC-1 these four bladder cancer cells after HCS treatment was measured by MTS,whereas thechanges of cell morphology were observed by transmission electron microscopy.The early apoptosis induced byHCS was evaluated by flow cytometry,and the expression level of apoptosis-related molecules(Bax,Bcl-2,XIAP,PARP,cleaved-Caspases 3,8,9)was detected using Western blot.We then evaluated the impact of HCS on theexpression of Fas/Fasl,TNF-alpha/TNFR1,and the activation of NF-Kappa B pathway,and furthermore the effect ofthese pathways in HCS induced-apoptosis were also detected.At last,xenograft tumor in nude mice was used tofurther investigate the antitumor effect of HCS in vivo.Results: Our results showed that HCS could efficiently inhibit proliferation and induce apoptosis in human bladdercancer cell lines.The expression of Fas,Fasl,TNF-alpha were all elevated at both mRNA and protein level after HCStreatment.Furthermore,down regulation of TNF-alpha,TNFR1,Fas or inhibition of Fas/Fasl interaction decreasedthe relative number of death cells induced by HCS.In vivo,HCS treatment significantly suppressed tumor growthand induced apoptosis in xenografts tumor in nude mice.Conclusions: HCS could efficiently inhibit proliferation and induce apoptosis in human bladder cancer cells in vitro and in vivo,which is largely mediated by Fas/Fasl and TNF-alpha/TNFR1 pathway...