title: Cisplatin and adriamycin resistance are associated with MutLalpha and mismatch repair deficiency in an ovarian tumor cell line.
abstract: In contrast to parental A2780 ovarian tumor cells, extracts of one doxorubicin-resistant and two independent cis-diamminedichloroplatinum(II)-resistant derivatives are defective in strand-specific mismatch repair. The repair defect of the three hypermutable, drug-resistant cell lines is only evident when the strand break that directs the reaction is located 3' to the mismatch, and in each case repair is restored to extracts by addition of purified MutLalpha heterodimer. As judged by immunological assay, drug resistance is associated with the virtual absence of the MutLalpha MLH1 subunit and greatly reduced levels of the PMS2 subunit. These findings implicate a functional mismatch repair system in the cytotoxic effects of these antitumor drugs and may have ramifications for their clinical application.
authors.affiliation: Howard Hughes Medical Institute and Department of Biochemistry, Duke University Medical Center, Durham, North Carolina 27710, USA.
authors.forename: J T
authors.initials: JT
authors.lastname: Drummond
authors.forename: A
authors.initials: A
authors.lastname: Anthoney
authors.forename: R
authors.initials: R
authors.lastname: Brown
authors.forename: P
authors.initials: P
authors.lastname: Modrich
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000251:Adenosine Triphosphatases; D002352:Carrier Proteins; D002945:Cisplatin; D004249:DNA Damage; D004260:DNA Repair; D045643:DNA Repair Enzymes; D004268:DNA-Binding Proteins; D018900:Dinucleotide Repeats; D004317:Doxorubicin; D004351:Drug Resistance; D005260:Female; D006801:Humans; D000070976:Mismatch Repair Endonuclease PMS2; D000070957:MutL Protein Homolog 1; D009363:Neoplasm Proteins / Q000235:genetics*; D009687:Nuclear Proteins; D010051:Ovarian Neoplasms / Q000235:genetics*; D014407:Tumor Cells, Cultured / Q000187:drug effects
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; C501486:MLH1 protein, human; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D004317:Doxorubicin; D000251:Adenosine Triphosphatases; C094934:PMS2 protein, human; D000070976:Mismatch Repair Endonuclease PMS2; D000070957:MutL Protein Homolog 1; D045643:DNA Repair Enzymes; D002945:Cisplatin