The purpose of this proposal is to study the role of active oxygen species in cancer cell cytotoxicity and to determine if lipids are a major target of these species. In order to study the role of active oxygen, superoxide dismutase (SOD) levels of parental and doxorubicin- resistant human breast carcinoma MCF-7 cells will be modulated and the effect on cell killing by selected antitumor agents (doxorubicin, bleomycin, ionizing radiation, tumor necrosis factor) determined. Modulation of superoxide dismutase will be accomplished by transfection of sense and anti-sense SOD cDNA. After transfection, clones with lower and higher than control levels of SOD activity will be isolated. These clones will then be tested for sensitivity to the selected antitumor agents. Both CuZnSOD and MnSOD will be transfected. Verification that superoxide dismutase modulation has occurred will be accomplished using enzyme activity, immunoreactive protein, Northern and Southern blot assays. Catalase, glutathione peroxidase, glutathione reductase, and glutathione levels will also be measured in the stable clones to determine if any of the other common antioxidants have been altered. Similar studies will be performed after glutathione peroxidase (GPX) transfection. GPX will be transferred into wild type MCF-7 cells as well as an SOD-overexpressing clone. The role of oxygen and lipid radicals will also be tested directly by measuring qualitatively and quantitatively the radicals present after treatment of control and SOD-and/or GPX-modified cells with the selected antitumor agents. Measurement of radicals will be accompanied by using the electron paramagnetic resonance technique of spin trapping. Last, the role of lipids in the antitumor effect will be studied. This will be done in two different ways: 1) measuring the amount of lipid peroxidation that occurs during tumor cell killing by the above agents; and 2) modifying the lipids of the cell and determining the effect on tumor cell killing by selected antitumor combinations in control and SOD- and/or GPX-transfected cell lines. This research should provide valuable new information on the mechanisms and targets of antitumor agents. It is hoped this knowledge will eventually lead to more powerful antitumor protocols.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Program Projects (P01)
Project #
5P01CA066081-04
Application #
6203295
Study Section
Project Start
1999-08-31
Project End
2001-06-30
Budget Start
1997-10-01
Budget End
1998-09-30
Support Year
4
Fiscal Year
1999
Total Cost
Indirect Cost
Name
University of Iowa
Department
Type
DUNS #
041294109
City
Iowa City
State
IA
Country
United States
Zip Code
52242
Khoo, Nicholas K H; Hebbar, Sachin; Zhao, Weiling et al. (2013) Differential activation of catalase expression and activity by PPAR agonists: implications for astrocyte protection in anti-glioma therapy. Redox Biol 1:70-9
Carr, Wanakee J; Oberley-Deegan, Rebecca E; Zhang, Yuping et al. (2011) Antioxidant proteins and reactive oxygen species are decreased in a murine epidermal side population with stem cell-like characteristics. Histochem Cell Biol 135:293-304
Du, J; Liu, J; Smith, B J et al. (2011) Role of Rac1-dependent NADPH oxidase in the growth of pancreatic cancer. Cancer Gene Ther 18:135-43
Sun, Wenqing G; Weydert, Christine J; Zhang, Yuping et al. (2010) Superoxide Enhances the Antitumor Combination of AdMnSOD Plus BCNU in Breast Cancer. Cancers (Basel) 2:68-87
Simons, Andrean L; Mattson, David M; Dornfeld, Ken et al. (2009) Glucose deprivation-induced metabolic oxidative stress and cancer therapy. J Cancer Res Ther 5 Suppl 1:S2-6
Aykin-Burns, NĂ¹khet; Ahmad, Iman M; Zhu, Yueming et al. (2009) Increased levels of superoxide and H2O2 mediate the differential susceptibility of cancer cells versus normal cells to glucose deprivation. Biochem J 418:29-37
Sun, Wenqing; Kalen, Amanda L; Smith, Brian J et al. (2009) Enhancing the antitumor activity of adriamycin and ionizing radiation. Cancer Res 69:4294-300
Du, Changbin; Gao, Zhen; Venkatesha, Venkatasubbaiah A et al. (2009) Mitochondrial ROS and radiation induced transformation in mouse embryonic fibroblasts. Cancer Biol Ther 8:1962-71
Jacobs, Kristi Muldoon; Pennington, J Daniel; Bisht, Kheem S et al. (2008) SIRT3 interacts with the daf-16 homolog FOXO3a in the mitochondria, as well as increases FOXO3a dependent gene expression. Int J Biol Sci 4:291-9
Weydert, Christine J; Zhang, Yuping; Sun, Wenqing et al. (2008) Increased oxidative stress created by adenoviral MnSOD or CuZnSOD plus BCNU (1,3-bis(2-chloroethyl)-1-nitrosourea) inhibits breast cancer cell growth. Free Radic Biol Med 44:856-67

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