? The overall goal of our research is to understand the molecular mechanisms of toxicity/carcinogenicity of environmental pollutants and the endogenous cellular defense systems to cope with pollutants. Drinking water contaminated with arsenic, a known carcinogen, is a worldwide public health issue. Epidemiology studies have linked arsenic exposure to human cancers, including skin, liver, lung, kidney, prostate, and bladder cancer. Arsenic can also cause cellular damage through generation of reactive oxygen species (ROS) that are even involved in the initiation, promotion, and progression of tumors. Although arsenic is a well defined carcinogen, it is not mutagenic and induces malignant transformation possibly by an epigenetic or cell signaling mechanism. Eukaryotic cells have evolved several defense mechanisms to cope with stress from the environment, one of which is the antioxidant response utilized by mammalian cells to neutralize ROS and to maintain cellular redox homeostasis. This antioxidant system is mediated through the antioxidant response element (ARE) sequence present in the promoters of several antioxidant and Phase II detoxification genes including glutathione S-transferase, NAD(P)H quinone oxidoreductase, glutamylcysteine synthetase, and heme-oxygenase. The antioxidant response system is mainly controlled by the transcription factor Nrf2. Activated by compounds possessing anti-cancer properties, the ARE-Nrf2-Keap1 signaling pathway has been clearly demonstrated to have profound effects on tumorigenesis. More significantly, Nrf2 knockout mice display increased sensitivity to chemical toxicants and carcinogens and are refractory to the protective actions of chemopreventive compounds. Therefore, we hypothesize that activation of the ARE-Nrf2-Keap1 pathway acts as an endogenous protective system against arsenic-induced toxicity and carcinogenicity. The following specific aims are intended to further elucidate the mechanism of Nrf2-activation in protection from arsenic-induced toxicity/tumorigenicity. This knowledge can potentially serve the scientific and medical community in our objective to create novel chemopreventive agents with increased specificity and efficacy, which will have broad impact on human health worldwide. We propose to (1) determine the protective role of the ARE-Nrf2- Keap1 pathway in arsenic-induced toxicity and carcinogenicity, (2) define the molecular mechanisms of activation of the ARE-Nrf2-Keap1 pathway by arsenic, and (3) define the protective role of the ARE-Nrf2-Keap1 pathway in arsenic-induced toxicity and tumorigenicity using the Nrf2 knockout mouse model. ? ? ? ?

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Research Project (R01)
Project #
5R01ES015010-03
Application #
7488593
Study Section
Special Emphasis Panel (ZES1-JAB-C (ON))
Program Officer
Reinlib, Leslie J
Project Start
2006-09-01
Project End
2011-08-31
Budget Start
2008-09-01
Budget End
2009-08-31
Support Year
3
Fiscal Year
2008
Total Cost
$390,682
Indirect Cost
Name
University of Arizona
Department
Pharmacology
Type
Schools of Pharmacy
DUNS #
806345617
City
Tucson
State
AZ
Country
United States
Zip Code
85721
Dodson, Matthew; Liu, Pengfei; Jiang, Tao et al. (2018) Increased O-GlcNAcylation of SNAP29 drives arsenic-induced autophagic dysfunction. Mol Cell Biol :
Dodson, Matthew; Zhang, Donna D (2017) Non-canonical activation of NRF2: New insights and its relevance to disease. Curr Pathobiol Rep 5:171-176
Tao, Shasha; Liu, Pengfei; Luo, Gang et al. (2017) p97 Negatively Regulates NRF2 by Extracting Ubiquitylated NRF2 from the KEAP1-CUL3 E3 Complex. Mol Cell Biol 37:
Melo-Cardenas, Johanna; Zhang, Yusi; Zhang, Donna D et al. (2016) Ubiquitin-specific peptidase 22 functions and its involvement in disease. Oncotarget 7:44848-44856
Rojo de la Vega, Montserrat; Dodson, Matthew; Gross, Christine et al. (2016) Role of Nrf2 and Autophagy in Acute Lung Injury. Curr Pharmacol Rep 2:91-101
Tao, Shasha; Rojo de la Vega, Montserrat; Quijada, Hector et al. (2016) Bixin protects mice against ventilation-induced lung injury in an NRF2-dependent manner. Sci Rep 6:18760
Long, Min; Rojo de la Vega, Montserrat; Wen, Qing et al. (2016) An Essential Role of NRF2 in Diabetic Wound Healing. Diabetes 65:780-93
Rojo de la Vega, Montserrat; Dodson, Matthew; Chapman, Eli et al. (2016) NRF2-targeted therapeutics: New targets and modes of NRF2 regulation. Curr Opin Toxicol 1:62-70
Long, Min; Tao, Shasha; Rojo de la Vega, Montserrat et al. (2015) Nrf2-dependent suppression of azoxymethane/dextran sulfate sodium-induced colon carcinogenesis by the cinnamon-derived dietary factor cinnamaldehyde. Cancer Prev Res (Phila) 8:444-54
Wu, Tongde; Harder, Bryan G; Wong, Pak K et al. (2015) Oxidative stress, mammospheres and Nrf2-new implication for breast cancer therapy? Mol Carcinog 54:1494-502

Showing the most recent 10 out of 58 publications