• Login
    View Item 
    •   UMB Digital Archive
    • School, Graduate
    • Theses and Dissertations All Schools
    • View Item
    •   UMB Digital Archive
    • School, Graduate
    • Theses and Dissertations All Schools
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of UMB Digital ArchiveCommunitiesPublication DateAuthorsTitlesSubjectsThis CollectionPublication DateAuthorsTitlesSubjects

    My Account

    LoginRegister

    Statistics

    Display statistics

    The DNA synthesome: A model for studying breast cancer cell DNA replication and the mechanisms of action of anti-breast cancer agents

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Find Full text
    Author
    Coll, Jennifer Marie
    Advisor
    Malkas, Linda H.
    Date
    1998
    Type
    dissertation
    
    Metadata
    Show full item record
    Abstract
    We have isolated a multiprotein complex for DNA synthesis, designated the DNA synthesome, from human breast cancer (MDA MB-468) cells, biopsied human breast tumor tissue and xenografts from nude mice injected with the human breast cancer cell line MCF-7. The breast cell DNA synthesome was shown to fully support the in vitro replication of simian virus 40 (SV40) origin-containing DNA in the presence of the viral large T-antigen. Moreover, our results obtained from a forward mutagenesis assay indicate that the DNA synthesome isolated from malignant breast cells possesses a lower fidelity for DNA replication in vitro than the complex from a nonmalignant breast cell line. The proteins and enzymes found to copurify with the breast cell DNA synthesome include: DNA polymerases alpha, delta, and epsilon, DNA primase, proliferating cell nuclear antigen (PCNA), replication factor C (RF-C), replication protein A (RP-A), DNA ligase, DNA topoisomerases I and II and poly(ADP-ribose) polymerase. To begin to determine the organization of these DNA synthetic proteins within the breast cell DNA synthesome, we performed co-immunoprecipitation experiments with antibodies directed against DNA polymerases alpha, delta and PCNA. We found that DNA polymerases alpha, delta, DNA primase, RF-C and PCNA tightly associate with each other in the complex, whereas DNA polymerase epsilon, PARP and several other components interact with the synthesome via an interaction with only PCNA or DNA polymerase alpha. Furthermore, we employed the breast cell DNA synthesome as a model to study the mechanisms of action of two anti-breast cancer agents that target the DNA synthetic process, irinotecan (CPT-11/SN-38) and etoposide (VP-16). We obtained novel data suggesting that both SN-38 and VP-16 stabilized cleavable complexes represent blocks to replication fork progression, as each agent caused an accumulation of short DNA products during synthesome mediated in vitro replication. Overall, our results indicate that breast cancer cells utilize an asymmetric multiprotein complex to mediate DNA synthesis and that utilization of the DNA synthesome as a drug model may provide important new insights into the mechanisms of action of SN-38 and VP-16.
    Description
    University of Maryland, Baltimore. Pharmacology and Experimental Therapeutics. Ph.D. 1998
    Keyword
    Biology, Molecular
    Health Sciences, Pharmacology
    DNA synthesome
    irinotecan
    Breast--Cancer
    Antineoplastic Agents
    Etoposide
    Identifier to cite or link to this item
    http://hdl.handle.net/10713/1341
    Collections
    Theses and Dissertations School of Medicine
    Theses and Dissertations All Schools

    entitlement

     
    DSpace software (copyright © 2002 - 2022)  DuraSpace
    Quick Guide | Policies | Contact Us | UMB Health Sciences & Human Services Library
    Open Repository is a service operated by 
    Atmire NV
     

    Export search results

    The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format.

    By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.

    To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export.

    After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.