title: [The genome structure and phenotypic characteristics of murine hybridoma 1F7 cells selected in the presence of adriamycin and ethidium bromide].
abstract: A study was made of geno- and phenotypic changes, associated with of multidrug resistance development in murine 1F7 hybridoma cells, selected for adriamycin and ethidium bromide resistance (1F7-EBR and 1F7-ADR). In both cell lines overexpression of mdr1 gene was observed, while amplification of mdr1 gene was detected only in 1F7-ADR cells. Karyotypic analysis revealed in resistant cells the presence of a specific marker M45 absent from parental cells, thus suggesting its selective importance. The M45 length instability, as well as the presence of a distal typical homogeneously stained region in it provide an evidence for a link between M45 and mdr1 gene amplification. The frequency of double minute chromosomes in parental lines was the same as in multidrug resistant lines. In 1F7-ADR cells, in contrast with 1F7-EBR cells, the enhancement of immunoglobulin production and the increase in immunoglobulin gamma 2b heavy chain gene expression were observed, which correlated with a decline in DNA-topoisomerase II activity.
authors.affiliation: Institute of Cytology, Russian Academy of Sciences, St. Petersburg.
authors.forename: M B
authors.initials: MB
authors.lastname: Meliksemian
authors.forename: E V
authors.initials: EV
authors.lastname: Berezkina
authors.forename: M A
authors.initials: MA
authors.lastname: Pavlenko
authors.forename: Z V
authors.initials: ZV
authors.lastname: Kovaleva
authors.forename: T M
authors.initials: TM
authors.lastname: Grinchuk
mesh_terms: D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects / Q000235:genetics; D002460:Cell Line; D004317:Doxorubicin / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D018432:Drug Resistance, Multiple / Q000235:genetics*; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D004996:Ethidium / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D016678:Genome; D005838:Genotype; D006825:Hybridomas / Q000187:drug effects*; D007621:Karyotyping; D051379:Mice; D010641:Phenotype
chemical_list: D000903:Antibiotics, Antineoplastic; D004791:Enzyme Inhibitors; D004317:Doxorubicin; D004996:Ethidium
vernacular_title: Issledovanie struktury genoma i fenotipicheskikh osobennosteĭ kletok myshinoĭ gibridomy 1F7, otselektirovannykh v prisutstvii adriamitsina i bromistogo étidiia.