title: Chemoimmunosensitization of the T24 human bladder cancer line to Fas-mediated cytotoxicity and apoptosis by cisplatin and 5-fluorouracil.
abstract: Previous studies have demonstrated that cisplatin (CDDP) sensitizes bladder cancer cells to Fas-mediated cytotoxicity and that CDDP also enhances the cytotoxic effect of 5-fluorouracil (5-FU). These agents mediate apoptosis and may share common intracellular pathways leading to cell killing. We reasoned that combination treatment with CDDP, 5-FU and anti-Fas monoclonal antibody (mAb) might overcome the drug-resistance. We investigated whether CDDP, 5-FU and anti-Fas mAb synergize in cytotoxicity and apoptosis against the T24 bladder cancer line. Cytotoxicity was monitored by a one day microculture tetrazolium dye assay. Treatment of T24 cells with anti-Fas mAb in combination with CDDP or 5-FU resulted in a synergistic cytotoxic effect. In addition, combination treatment of T24 cells with CDDP, 5-FU and anti-Fas mAb further enhanced the synergistic cytotoxicity achieved by two agents. The synergy achieved in cytotoxicity with CDDP, 5-FU and anti-Fas mAb was also achieved in apoptosis. The current study demonstrates that combination treatment of bladder cancer cells with CDDP, 5-FU and anti-Fas mAb overcomes their resistance. In addition, the sensitization required low concentrations of CDDP and 5-FU, and thus supporting the potential in vivo application of combination of CDDP, 5-FU and immunotherapy in the treatment of drug-resistant bladder cancer.
authors.affiliation: Department of Urology, Faculty of Medicine, Kyoto University, Sakyo-ku, Kyoto 606, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Mizutani
authors.forename: X X
authors.initials: XX
authors.lastname: Wu
authors.forename: O
authors.initials: O
authors.lastname: Yoshida
authors.forename: T
authors.initials: T
authors.lastname: Shirasaka
authors.forename: B
authors.initials: B
authors.lastname: Bonavida
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology / Q000627:therapeutic use*; D000970:Antineoplastic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D017209:Apoptosis / Q000187:drug effects* / Q000276:immunology; D002945:Cisplatin / Q000494:pharmacology* / Q000627:therapeutic use; D003602:Cytotoxicity, Immunologic; D019008:Drug Resistance, Neoplasm; D004357:Drug Synergism; D004359:Drug Therapy, Combination; D005472:Fluorouracil / Q000494:pharmacology* / Q000627:therapeutic use; D006801:Humans; D014407:Tumor Cells, Cultured; D001749:Urinary Bladder Neoplasms / Q000188:drug therapy* / Q000276:immunology* / Q000473:pathology; D019014:fas Receptor / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000970:Antineoplastic Agents; D019014:fas Receptor; D002945:Cisplatin; D005472:Fluorouracil