PT - JOURNAL ARTICLE AU - PAULA A. OLIVEIRA AU - REGINA ARANTES-RODRIGUES AU - CLARISSE SOUSA-DINIZ AU - AURA COLAÇO AU - LÍGIA LOURENÇO AU - LUIS FELIPE. DE LA CRUZ P. AU - VÍTOR MOREIRA DA SILVA AU - JULIETA AFONSO AU - CARLOS LOPES AU - LÚCIO SANTOS TI - The Effects of Sirolimus on Urothelial Lesions Chemically Induced in ICR Mice by BBN DP - 2009 Aug 01 TA - Anticancer Research PG - 3221--3226 VI - 29 IP - 8 4099 - http://ar.iiarjournals.org/content/29/8/3221.short 4100 - http://ar.iiarjournals.org/content/29/8/3221.full SO - Anticancer Res2009 Aug 01; 29 AB - Background: Sirolimus was originally used as an immunosuppressant drug but recent reports have indicated that it may have other potential biological effects as an anticancer drug. The chemopreventive efficacy of sirolimus was evaluated in an experimental model of invasive urinary bladder cancer. Materials and Methods: ICR mice received N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) in drinking water for a period of twelve weeks. Sirolimus was administered 5 days a week. Animals were sacrificed either one or four weeks after their final treatment. Ki-67 was immunohistochemically analysed in paraffin-embedded tissue. Results: No evidence of host toxicity was found. The incidence of BBN-induced invasive urothelial carcinoma was significantly reduced in mice treated with sirolimus. Preneoplastic and neoplastic lesions exhibited a significant decrease in cellular proliferation. Conclusion: Histopathological and immunohistochemical studies showed that sirolimus reduced tumour incidence and proliferation. Sirolimus should be considered for further in vitro and in vivo studies in order to provide evidence of effectiveness.