Molecular dosimetry of N7-(2-hydroxypropyl)guanine in tissues of F344 rats after inhalation exposure to propylene oxide.
Carcinogenesis 24, 1233-1238 (2003)
Propylene oxide (PO) is a high-volume chemical intermediate that causes a low incidence of nasal tumors in rodents exposed to high concentrations (≥300 p.p.m.). PO reacts with DNA forming mainly N7-(2-hydroxypropyl)guanine (7-HPG). The exposure-dependent accumulation of 7-HPG in nasal respiratory epithelium (NRE), lung and liver was determined in male F344 rats exposed to PO (0, 5, 25, 50, 300 or 500 p.p.m.) by the inhalation route for 3 or 20 days (6 h/day; 5 days/week). These exposures ranged from low concentrations, such as those potentially occurring in the workplace, to high concentrations that proved to be carcinogenic in rodents. Analysis of 7-HPG in DNA by gas chromatography–high-resolution mass spectrometry (GC–HRMS) showed a linear response in 7-HPG for all three tissues after 3 days of exposure, and for NRE and lung after 20 days of exposure. A slightly sublinear response in 7-HPG was observed in liver after 20 days of exposure. For both exposure periods, the NRE had the highest concentration of 7-HPG, followed by lung and liver. The amount of 7-HPG in NRE was seven and 17 times higher than in lung and liver, respectively, for the 3 day exposures. For the 20 day exposures, the concentration of 7-HPG in NRE was six and 13 times higher than that in lung and liver, respectively, over the concentration range studied. These results demonstrate a much higher extent of DNA alkylation in the target tissue for carcinogenesis, than in non-target tissues. As PO-induced tumor formation was highly sublinear, occurring only at high vapor concentrations, whereas 7-HPG adducts were shown to be linearly dependent on airborne concentration, these results suggest that 7-HPG is not sufficient for PO nasal carcinogenesis and that other factors such as increased cell proliferation may be important in determining the tumor exposure response.
Impact Factor
Scopus SNIP
Web of Science
Times Cited
Scopus
Cited By
Altmetric
Publication type
Article: Journal article
Document type
Scientific Article
Thesis type
Editors
Keywords
AP, apurinic/apyrimidinic ddH2O, double-distilled water GC–HRMS, gas chromatography–high-resolution mass spectrometry N6-HPdAdo, N6-(2-hydroxypropyl)deoxyadenosine 7-HPG, N7-(2-hydroxypropyl)guanine NRE, nasal respiratory epithelium PO, propylene oxide
Keywords plus
Language
english
Publication Year
2003
Prepublished in Year
HGF-reported in Year
0
ISSN (print) / ISBN
0143-3334
e-ISSN
1460-2180
ISBN
Book Volume Title
Conference Title
Conference Date
Conference Location
Proceedings Title
Quellenangaben
Volume: 24,
Issue: 7,
Pages: 1233-1238
Article Number: ,
Supplement: ,
Series
Publisher
Oxford University Press
Publishing Place
Day of Oral Examination
0000-00-00
Advisor
Referee
Examiner
Topic
University
University place
Faculty
Publication date
0000-00-00
Application date
0000-00-00
Patent owner
Further owners
Application country
Patent priority
Reviewing status
Peer reviewed
POF-Topic(s)
30203 - Molecular Targets and Therapies
Research field(s)
Enabling and Novel Technologies
PSP Element(s)
G-505200-002
Grants
Copyright
Erfassungsdatum
2003-07-02