title: V79 Chinese hamster lung cells resistant to the bis-alkylator bizelesin are multidrug-resistant.
abstract: Bizelesin (U-77779) is a highly potent bis-alkylating antitumor agent that is effective against several tumor systems in vitro and in vivo. V79 cells that were 125- to 250-fold resistant to bizelesin developed after constant exposure to gradually increasing concentrations of the drug. Resistant cells exhibited a multidrug-resistant phenotype and genotype as indicated by cross-resistant to several structurally and functionally unrelated drugs, e.g., colchicine, actinomycin D, and Adriamycin, and overexpression of mdr mRNA. Very low levels of cross-resistance to the alkylating agents cisplatin and melphalan were seen. Multidrug-resistant mouse leukemia (P388/Adriamycin-resistant) and human (KB/vinblastine-resistant) cells were also resistant to bizelesin. Bizelesin resistance was unstable and decreased when cells were grown in the absence of the drug. Resistant and sensitive cell lines had similar levels of glutathione, and bizelesin cytotoxicity for resistant cells was not markedly affected by treatment with buthionine sulfoximine. Cross-resistance between bizelesin and several of its analogs is reported.
authors.affiliation: Department of Cancer and Infectious Diseases Research, Upjohn Company, Kalamazoo, MI 49001.
authors.forename: R K
authors.initials: RK
authors.lastname: Butryn
authors.forename: K S
authors.initials: KS
authors.lastname: Smith
authors.forename: E G
authors.initials: EG
authors.lastname: Adams
authors.forename: I
authors.initials: I
authors.lastname: Abraham
authors.forename: J
authors.initials: J
authors.lastname: Stackpole
authors.forename: K E
authors.initials: KE
authors.lastname: Sampson
authors.forename: B K
authors.initials: BK
authors.lastname: Bhuyan
mesh_terms: D000477:Alkylating Agents / Q000494:pharmacology; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D015152:Blotting, Northern; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D006224:Cricetinae; D003412:Cricetulus; D004351:Drug Resistance / Q000502:physiology; D000080890:Duocarmycins; D005347:Fibroblasts / Q000187:drug effects; D005838:Genotype; D006801:Humans; D007211:Indoles / Q000494:pharmacology*; D008168:Lung / Q000166:cytology* / Q000187:drug effects; D051379:Mice; D010641:Phenotype; D012313:RNA / Q000032:analysis; D014407:Tumor Cells, Cultured; D014508:Urea / Q000031:analogs & derivatives* / Q000494:pharmacology; D014700:Verapamil / Q000494:pharmacology
chemical_list: D000477:Alkylating Agents; D000970:Antineoplastic Agents; D000080890:Duocarmycins; D007211:Indoles; D012313:RNA; D014508:Urea; D014700:Verapamil; C072257:bizelesin