This is the FIRST award application to study oxidative stress during glucocorticoid-mediated lymphocyte apoptosis. The hypothesis is that oxidative stress is required for glucocorticoid-mediated lymphocyte apoptosis. This application will test whether the observed down-regulation of the antioxidant defense enzymes is essential for apoptosis. The applicant will establish the mechanism by which antioxidant defense transcripts are down-regulated. Finally the applicant proposes to develop sensitive bioassays for representative oxidative damages to macromolecules in cells and to define targets representing oxidative damages during apoptosis. Specifically, Aim 1 is to test whether a reduction in the antioxidant defense is essential for glucocorticoid-mediated lymphocyte apoptosis by transfecting the WEHI 7.2 lymphocyte cell line with sense and antisense antioxidant defense expression vectors and determining whether resistance to apoptosis depends on the strength of the cellular antioxidant defense.
Specific Aim 2 is to determine the mechanism by which glucocorticoids down-regulate the antioxidant defense by measuring RNA stability and gene transcription rates and using structural/functional analysis of the regulated transcripts or gene sequences to identify sites that are regulated during apoptosis, and Specific Aim 3 is to identify targets of oxidative stress during apoptosis by using gas chromatography with electron capture detection to measure lipid peroxidation. Immunoassay will be used to detect oxidized proteins, gel shifts, and reporter constructs to monitor activity of redox-sensitive transcript or transcription factors, and a PCR-based method will assay oxidative damages to mitochondrial DNA. The information gained from the proposed study will be significant to the understanding of mechanisms by which aberrant control of the cellular redox state promotes disease, specifically through an effect on apoptosis. The future goal is to identify new targets for treatments aimed at restoring control of apoptosis in diseased tissues.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
First Independent Research Support & Transition (FIRST) Awards (R29)
Project #
5R29CA071768-02
Application #
2443288
Study Section
Experimental Therapeutics Subcommittee 1 (ET)
Project Start
1996-07-15
Project End
2001-06-30
Budget Start
1997-07-01
Budget End
1998-06-30
Support Year
2
Fiscal Year
1997
Total Cost
Indirect Cost
Name
University of Arizona
Department
Pathology
Type
Schools of Medicine
DUNS #
City
Tucson
State
AZ
Country
United States
Zip Code
85721
Jaramillo, Melba C; Briehl, Margaret M; Batinic-Haberle, Ines et al. (2015) Manganese (III) meso-tetrakis N-ethylpyridinium-2-yl porphyrin acts as a pro-oxidant to inhibit electron transport chain proteins, modulate bioenergetics, and enhance the response to chemotherapy in lymphoma cells. Free Radic Biol Med 83:89-100
Briehl, Margaret M (2015) Oxygen in human health from life to death--An approach to teaching redox biology and signaling to graduate and medical students. Redox Biol 5:124-39
Lee, Kristy; Hart, Matthew R; Briehl, Margaret M et al. (2014) The copper chelator ATN-224 induces caspase-independent cell death in diffuse large B cell lymphoma. Int J Oncol 45:439-47
Lee, Kristy; Briehl, Margaret M; Mazar, Andrew P et al. (2013) The copper chelator ATN-224 induces peroxynitrite-dependent cell death in hematological malignancies. Free Radic Biol Med 60:157-67
Jaramillo, Melba C; Briehl, Margaret M; Crapo, James D et al. (2012) Manganese porphyrin, MnTE-2-PyP5+, Acts as a pro-oxidant to potentiate glucocorticoid-induced apoptosis in lymphoma cells. Free Radic Biol Med 52:1272-84
Tome, Margaret E; Frye, Jennifer B; Coyle, Donna L et al. (2012) Lymphoma cells with increased anti-oxidant defenses acquire chemoresistance. Exp Ther Med 3:845-852
Wilkinson, Sarah T; Tome, Margaret E; Briehl, Margaret M (2012) Mitochondrial adaptations to oxidative stress confer resistance to apoptosis in lymphoma cells. Int J Mol Sci 13:10212-28
Tome, Margaret E; Jaramillo, Melba C; Briehl, Margaret M (2011) Hydrogen peroxide signaling is required for glucocorticoid-induced apoptosis in lymphoma cells. Free Radic Biol Med 51:2048-59
Wilkinson, Sarah T; Johnson, David B F; Tardif, Heather L et al. (2010) Increased cytochrome c correlates with poor survival in aggressive lymphoma. Oncol Lett 1:227-230
Jaramillo, Melba C; Frye, Jennifer B; Crapo, James D et al. (2009) Increased manganese superoxide dismutase expression or treatment with manganese porphyrin potentiates dexamethasone-induced apoptosis in lymphoma cells. Cancer Res 69:5450-7

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