Many cytotoxic drugs used in cancer chemotherapy inhibit DNA replication and induce programmed cell death (apoptosis) in tumor cells. It is unknown to what extent the inhibition of DNA replication per se is responsible for the induction of cell death by anticancer drugs. Cell death in cycling cells can be induced by treatment with known inhibitors of DNA replication, such as aphidicolin, a mycotoxin which inhibits elongation of replication by DNA polymerases alpha and delta, or mimosine, a plant amino acid which prevents initiation of replication in mammalian cells. The main goal of this application is to identify genes and genetic pathways that are involved in the induction of cell death by inhibitors of DNA replication. These genes will be identified through expression selection of genetic suppressor elements (GSE), short cDNA fragments that inhibit gene expression by encoding dominantly acting peptides or inhibitory antisense RNA. A normalized library of GSEs in a retroviral vector will be transduced into HeLa cells, and GSEs which protect cells from aphidicolin- or mimosine-induced cell death will be isolated. These GSEs will be characterized for their efficacy, effects on cell cycle progression, ability to protect cells against different DNA replication inhibitors and cell-type specificity. Full-length cDNAs for human genes corresponding to the selected GSEs will be isolated, and their structure and expression patterns in the cell cycle will be characterized. The isolated GSEs will also be tested for their effects on cellular response to replication-inhibiting chemotherapeutic drugs, to determine the role of replication-based mechanisms of cytotoxicity in their antitumor effect.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
First Independent Research Support & Transition (FIRST) Awards (R29)
Project #
5R29CA070263-02
Application #
2390917
Study Section
Experimental Therapeutics Subcommittee 1 (ET)
Project Start
1996-04-05
Project End
2001-03-31
Budget Start
1997-04-01
Budget End
1998-03-31
Support Year
2
Fiscal Year
1997
Total Cost
Indirect Cost
Name
University of Illinois at Chicago
Department
Genetics
Type
Schools of Medicine
DUNS #
121911077
City
Chicago
State
IL
Country
United States
Zip Code
60612
Davidovich, Irina A; Levenson, Anait S; Levenson Chernokhvostov, Victor V (2004) Overexpression of DcR1 and survivin in genetically modified cells with pleiotropic drug resistance. Cancer Lett 211:189-97
Levenson, V V; Davidovich, I A; Roninson, I B (2000) Pleiotropic resistance to DNA-interactive drugs is associated with increased expression of genes involved in DNA replication, repair, and stress response. Cancer Res 60:5027-30
Levenson, V V; Lausch, E; Kirschling, D J et al. (1999) A combination of genetic suppressor elements produces resistance to drugs inhibiting DNA replication. Somat Cell Mol Genet 25:9-26
Levenson, V V; Transue, E D; Roninson, I B (1998) Internal ribosomal entry site-containing retroviral vectors with green fluorescent protein and drug resistance markers. Hum Gene Ther 9:1233-6