Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants that have been upgraded to human carcinogens by the WHO, International Agency for Research on Cancer (IARC). PAH are airborne pollutants found in smoke from fossil-fuel combustion, car-exhaust, fine-particulate matter (PM2.5), and first and second hand tobacco smoke. Inhalation toxicity likely results in cancer of the lung and airway. PAH require metabolic activation to exert their deleterious effects, however, the major pathway of PAH activation in the carcinogen target cell, normal human bronchial epithelial cells (NHBE) is uncertain. Three pathways have been proposed: the radical cation pathway (P450-peroxidase dependent) which produces depurinating-DNA adducts;the diol-epoxide pathway (P450-dependent) which produces stable-DMA adducts;and the formation of reactive and redox-active o-quinones (aldo-keto reductase (AKR) dependent), which can give rise to covalent DMA adducts and oxidative damage of DMA. Based on the consistent over-expression of AKR isoforms and the loss of one allele of hOGG1 (human oxoguanine glycosylase the base excision repair enzyme specific for removal 8-oxo-dGuo from DMA) in patients with lung cancer, we hypothesize that AKRs activate PAHs in human bronchial epithelial (HBE) cells and this results in increased oxidative DNA damage.
Four aims are proposed to test this hypothesis.
In Aim #1, the metabolism of benzo[a]pyrene (BP) will be measured in parental H358 cells (transformed HBE cells) in the presence and absence of (P450 and AKR) induction and the levels of radical cation metabolites (BP-1,6-, 3,6- and 6,12-diones), diol-epoxide metabolites (BP-tetrols) and o-quinone metabolites (BP-7,8-dione) will be quantified and identified by LC- MS.
In Aim#2, a stable isotope dilution method using [13C]-BP-metabolites as internal standards to monitor the BP-metabolome will be established.
In Aim#3, NHBE cells immortalized with cdk4 and human telomerase will be used to monitor the BP-metabolome by LC-MS stable isotope dilution methodology in the presence and absence of P450 and AKR inducers.
In Aim#4, the ability of BP, BP-7,8-dihydrodiol (AKR substrate) and BP-7,8-dione (AKR product) to cause AKR-dependent 8-oxo-dGuo formation will be examined in NHBE cells. These studies will identify major BP-metabolites in NHBE cells which could be used to biomonitor human PAH exposure, and validate candidate genes for genetic predisposition studies.

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Research Project (R01)
Project #
5R01ES015857-04
Application #
7808852
Study Section
Special Emphasis Panel (ZRG1-ONC-P (02))
Program Officer
Carlin, Danielle J
Project Start
2007-08-03
Project End
2012-04-30
Budget Start
2010-05-01
Budget End
2011-04-30
Support Year
4
Fiscal Year
2010
Total Cost
$355,448
Indirect Cost
Name
University of Pennsylvania
Department
Pharmacology
Type
Schools of Medicine
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Gelhaus, Stacy L; Gilad, Oren; Hwang, Wei-Ting et al. (2012) Multidrug resistance protein (MRP) 4 attenuates benzo[a]pyrene-mediated DNA-adduct formation in human bronchoalveolar H358 cells. Toxicol Lett 209:58-66
Wu, Anhui; Xu, Daiwang; Lu, Ding et al. (2012) Synthesis of (13)C4-labelled oxidized metabolites of the carcinogenic polycyclic aromatic hydrocarbon benzo[a]pyrene. Tetrahedron 68:
Jin, Yi (2011) Activities of aldo-keto reductase 1 enzymes on two inhaled corticosteroids: implications for the pharmacological effects of inhaled corticosteroids. Chem Biol Interact 191:234-8
Lu, Ding; Harvey, Ronald G; Blair, Ian A et al. (2011) Quantitation of benzo[a]pyrene metabolic profiles in human bronchoalveolar (H358) cells by stable isotope dilution liquid chromatography-atmospheric pressure chemical ionization mass spectrometry. Chem Res Toxicol 24:1905-14
Jin, Yi; Mesaros, A Clementina; Blair, Ian A et al. (2011) Stereospecific reduction of 5?-reduced steroids by human ketosteroid reductases of the AKR (aldo-keto reductase) superfamily: role of AKR1C1-AKR1C4 in the metabolism of testosterone and progesterone via the 5?-reductase pathway. Biochem J 437:53-61
Beers, Michael F; Morrisey, Edward E (2011) The three R's of lung health and disease: repair, remodeling, and regeneration. J Clin Invest 121:2065-73
Gelhaus, Stacy L; Harvey, Ronald G; Penning, Trevor M et al. (2011) Regulation of benzo[a]pyrene-mediated DNA- and glutathione-adduct formation by 2,3,7,8-tetrachlorodibenzo-p-dioxin in human lung cells. Chem Res Toxicol 24:89-98
Wu, Anhui; Duan, Yazhen; Xu, Daiwang et al. (2010) Regiospecific oxidation of polycyclic aromatic phenols to quinones by hypervalent iodine reagents. Tetrahedron 66:2111-2118
MacLeod, A Kenneth; McMahon, Michael; Plummer, Simon M et al. (2009) Characterization of the cancer chemopreventive NRF2-dependent gene battery in human keratinocytes: demonstration that the KEAP1-NRF2 pathway, and not the BACH1-NRF2 pathway, controls cytoprotection against electrophiles as well as redox-cycling compounds. Carcinogenesis 30:1571-80
Xu, Daiwang; Penning, Trevor M; Blair, Ian A et al. (2009) Synthesis of phenol and quinone metabolites of benzo[a]pyrene, a carcinogenic component of tobacco smoke implicated in lung cancer. J Org Chem 74:597-604

Showing the most recent 10 out of 17 publications