title: Molecular cytogenetic characterization of drug-resistant leukemia cell lines by comparative genomic hybridization and fluorescence in situ hybridization.
abstract: Resistance to chemotherapeutic drugs is one of the major difficulties encountered during cancer chemotherapy. To detect genomic aberrations underlying the acquired drug resistance, we examined three cultured human myelomonocytic leukemia cell sublines each resistant to adriamycin (ADR), 1-beta-1-D-arabinofuranosylcytosine (ara-C), or vincristine (VCR), using comparative genomic hybridization (CGH), fluorescence in situ hybridization (FISH), RT-PCR, and western blot techniques. Chromosomes 7, 10 and 16 most conspicuously showed frequent aberrations among the resistant sublines as compared to the parental KY-821 cell line. In ADR-resistant cells, gains at 7q21, 16p12, 16p13.1-13.3, 16q11.1-q12.1, and losses at 7p22-pter, 7q36-qter, 10p12, 10p11.2-pter, 10q21-q25, 10q26-qter were notable. In ara-C-resistant cells, no remarkable gain or loss on chromosome 7, but losses at 10p14-pter, 10q26-qter and 16p11.2-p11.3 were observed. In VCR-resistant cells, gain at 7q21 and losses at 10p11-p13, 10p15 and 16p11.2-p13.3 were found. FISH identified amplified signals for the MDR-1 gene located at 7q21.1 in ADR- and VCR- but not ara-C-resistant cells, and for the MRP-1 gene located at 16p13.1 in ADR-resistant cells. These findings were validated at the mRNA and protein levels. Overlapping of the amplified MRP-1 gene with MDR-1 gene may play a critical part in the acquisition of resistance to ADR. Resistance to ara-C excluded MDR-1 gene involvement and highlighted other key genes such as MXR gene. Several other genes putatively involved in the development of drug resistance might lie in other aberrated chromosomal regions.
authors.affiliation: The Department of Molecular Pathology, Institute of Gerontology, Nippon Medical School, Nakahara-ku, Kawasaki 211-8533, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Shimizu
authors.forename: Takeaki
authors.initials: T
authors.lastname: Fukuda
authors.forename: Mohammad
authors.initials: M
authors.lastname: Ghazizadeh
authors.forename: Mikio
authors.initials: M
authors.lastname: Nagashima
authors.forename: Oichi
authors.initials: O
authors.lastname: Kawanami
authors.forename: Toshimitsu
authors.initials: T
authors.lastname: Suzuki
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000494:pharmacology; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology; D015153:Blotting, Western; D002467:Cell Nucleus / Q000378:metabolism; D002874:Chromosome Mapping; D003561:Cytarabine / Q000494:pharmacology; D004317:Doxorubicin / Q000494:pharmacology; D019008:Drug Resistance, Neoplasm; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D020128:Inhibitory Concentration 50; D007938:Leukemia / Q000235:genetics* / Q000378:metabolism; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000378:metabolism; D009693:Nucleic Acid Hybridization; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured; D014750:Vincristine / Q000494:pharmacology
chemical_list: D000964:Antimetabolites, Antineoplastic; D000970:Antineoplastic Agents; D000972:Antineoplastic Agents, Phytogenic; D003561:Cytarabine; D004317:Doxorubicin; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D014750:Vincristine; C421109:multidrug resistance-associated protein 1