1
|
Wilson KA, Jeong YER, Wetmore SD. Multiscale computational investigations of the translesion synthesis bypass of tobacco-derived DNA adducts: critical insights that complement experimental biochemical studies. Phys Chem Chem Phys 2022; 24:10667-10683. [PMID: 35502640 DOI: 10.1039/d2cp00481j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2023]
Abstract
Among the numerous agents that damage DNA, tobacco products remain one of the most lethal and result in the most diverse set of DNA lesions. This perspective aims to provide an overview of computational work conducted to complement experimental biochemical studies on the mutagenicity of adducts derived from the most potent tobacco carcinogen, namely 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (nicotine-derived nitrosaminoketone or NNK). Lesions ranging from the smallest methylated thymine derivatives to the larger, flexible pyridyloxobutyl (POB) guanine adducts are considered. Insights are obtained from density functional theory (DFT) calculations and molecular dynamics (MD) simulations into the damaged nucleobase and nucleoside structures, the accommodation of the lesions in the active site of key human polymerases, the intrinsic base pairing potentials of the adducts, and dNTP incorporation opposite the lesions. Overall, the computational data provide atomic level information that can rationalize the differential mutagenic properties of tobacco-derived lesions and uncover important insights into the impact of adduct size, nucleobase, position, and chemical composition of the bulky moiety.
Collapse
Affiliation(s)
- Katie A Wilson
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute (ARRTI) and Southern Alberta Genome Sciences Center (SAGSC), University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta, T1K 3M4, Canada.
| | - Ye Eun Rebecca Jeong
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute (ARRTI) and Southern Alberta Genome Sciences Center (SAGSC), University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta, T1K 3M4, Canada.
| | - Stacey D Wetmore
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute (ARRTI) and Southern Alberta Genome Sciences Center (SAGSC), University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta, T1K 3M4, Canada.
| |
Collapse
|
2
|
Li Y, Hecht SS. Metabolism and DNA Adduct Formation of Tobacco-Specific N-Nitrosamines. Int J Mol Sci 2022; 23:5109. [PMID: 35563500 PMCID: PMC9104174 DOI: 10.3390/ijms23095109] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 04/29/2022] [Accepted: 04/30/2022] [Indexed: 01/06/2023] Open
Abstract
The tobacco-specific N-nitrosamines 4-(N-nitrosomethylamino)-1-(3-pyridyl)-1-butanone (NNK) and N'-nitrosonornicotine (NNN) always occur together and exclusively in tobacco products or in environments contaminated by tobacco smoke. They have been classified as "carcinogenic to humans" by the International Agency for Research on Cancer. In 1998, we published a review of the biochemistry, biology and carcinogenicity of tobacco-specific nitrosamines. Over the past 20 years, considerable progress has been made in our understanding of the mechanisms of metabolism and DNA adduct formation by these two important carcinogens, along with progress on their carcinogenicity and mutagenicity. In this review, we aim to provide an update on the carcinogenicity and mechanisms of the metabolism and DNA interactions of NNK and NNN.
Collapse
Affiliation(s)
- Yupeng Li
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA;
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis, MN 55455, USA
| | - Stephen S. Hecht
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA;
| |
Collapse
|
3
|
Hu Q, Upadhyaya P, Hecht SS, Aly FZ, Huo Z, Xing C. Characterization of adductomic totality of NNK, (R)-NNAL and (S)-NNAL in A/J mice, and their correlations with distinct lung carcinogenicity. Carcinogenesis 2022; 43:170-181. [PMID: 34919675 PMCID: PMC8947227 DOI: 10.1093/carcin/bgab113] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 11/15/2021] [Accepted: 11/25/2021] [Indexed: 11/15/2023] Open
Abstract
Lung cancer is the leading cause of cancer-related deaths. While tobacco use is the main cause, only 10-20% of smokers eventually develop clinical lung cancer. Thus, the ability of lung cancer risk prediction among smokers could transform lung cancer management with early preventive interventions. Given that DNA damage by tobacco carcinogens is the potential root cause of lung carcinogenesis, we characterized the adductomic totality of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (a potent lung carcinogen in tobacco, commonly known as NNK) in the target lung tissues, the liver tissues and the peripheral serum samples in a single-dose NNK-induced lung carcinogenesis A/J mouse model. We also characterized these adductomic totalities from the two enantiomers of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL, the major in vivo metabolite of NNK) given their distinct carcinogenicity in A/J mice. With these adductomic data, we demonstrated that tissue protein adductomics have the highest abundance. We also identified that the adductomic levels at the 8 h time point after carcinogen exposure were among the highest. More importantly, the relationships among these adductomics were characterized with overall strong positive linear correlations, demonstrating the potential of using peripheral serum protein adductomics to reflect DNA adductomics in the target lung tissues. Lastly, we explored the relationships of these adductomics with lung tumor status in A/J mice, providing preliminary but promising evidence of the feasibility of lung cancer risk prediction using peripheral adductomic profiling.
Collapse
Affiliation(s)
- Qi Hu
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL, USA
| | - Pramod Upadhyaya
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
| | - Stephen S Hecht
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
| | - F Zahra Aly
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida, 1345 Center Drive, Gainesville, FL, USA
| | - Zhiguang Huo
- Department of Biostatistics, College of Public Health & Health Professions, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Chengguo Xing
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL, USA
| |
Collapse
|
4
|
Guo J, Chen H, Upadhyaya P, Zhao Y, Turesky RJ, Hecht SS. Mass Spectrometric Quantitation of Apurinic/Apyrimidinic Sites in Tissue DNA of Rats Exposed to Tobacco-Specific Nitrosamines and in Lung and Leukocyte DNA of Cigarette Smokers and Nonsmokers. Chem Res Toxicol 2020; 33:2475-2486. [PMID: 32833447 PMCID: PMC7574376 DOI: 10.1021/acs.chemrestox.0c00265] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Metabolic activation of the carcinogenic tobacco-specific nitrosamines 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N'-nitrosonornicotine (NNN) results in formation of reactive electrophiles that modify DNA to produce a variety of products including methyl, 4-(3-pyridyl)-4-oxobutyl (POB)-, and 4-(3-pyridyl)-4-hydroxybutyl adducts. Among these are adducts such as 7-POB-deoxyguanosine (N7POBdG) which can lead to apurinic/apyrimidinic (AP) sites by facile hydrolysis of the base-deoxyribonucleoside bond. In this study, we used a recently developed highly sensitive mass spectrometric method to quantitate AP sites by derivatization with O-(pyridin-3-yl-methyl)hydroxylamine (PMOA) (detection limit, 2 AP sites per 108 nucleotides). AP sites were quantified in DNA isolated from tissues of rats treated with NNN and NNK and from human lung tissue and leukocytes of cigarette smokers and nonsmokers. Rats treated with 5 or 21 mg/kg bw NNK for 4 days by s.c. injection had 2-6 and 2-17 times more AP sites than controls in liver and lung DNA (p < 0.05). Increases in AP sites were also found in liver DNA of rats exposed for 10 and 30 weeks (p < 0.05) but not for 50 and 70 weeks to 5 ppm of NNK in their drinking water. Levels of N7POBG were significantly correlated with AP sites in rats treated with NNK. In rats treated with 14 ppm (S)-NNN in their drinking water for 10 weeks, increased AP site formation compared to controls was observed in oral and nasal respiratory mucosa DNA (p < 0.05). No significant increase in AP sites was found in human lung and leukocyte DNA of cigarette smokers compared to nonsmokers, although AP sites in leukocyte DNA were significantly correlated with urinary levels of the NNK metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL). This is the first study to use mass spectrometry based methods to examine AP site formation by carcinogenic tobacco-specific nitrosamines in laboratory animals and to evaluate AP sites in DNA of smokers and nonsmokers.
Collapse
Affiliation(s)
- Jiehong Guo
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Haoqing Chen
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Pramod Upadhyaya
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Yingchun Zhao
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Robert J. Turesky
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Stephen S. Hecht
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| |
Collapse
|
5
|
Sarker AH, Trego KS, Zhang W, Jacob P, Snijders A, Mao JH, Schick SF, Cooper PK, Hang B. Thirdhand smoke exposure causes replication stress and impaired transcription in human lung cells. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2020; 61:635-646. [PMID: 32267018 PMCID: PMC7363442 DOI: 10.1002/em.22372] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/29/2020] [Accepted: 03/27/2020] [Indexed: 05/12/2023]
Abstract
Thirdhand cigarette smoke (THS) is a newly described toxin that lingers in the indoor environment long after cigarettes have been extinguished. Emerging results from both cellular and animal model studies suggest that THS is a potential human health hazard. DNA damage derived from THS exposure could have genotoxic consequences that would lead to the development of diseases. However, THS exposure-induced interference with fundamental DNA transactions such as replication and transcription, and the role of DNA repair in ameliorating such effects, remain unexplored. Here, we found that THS exposure increased the percentage of cells in S-phase, suggesting impaired S-phase progression. Key DNA damage response proteins including RPA, ATR, ATM, CHK1, and BRCA1 were activated in lung cells exposed to THS, consistent with replication stress. In addition, THS exposure caused increased 53BP1 foci, indicating DNA double-strand break induction. Consistent with these results, we observed increased micronuclei formation, a marker of genomic instability, in THS-exposed cells. Exposure to THS also caused a significant increase in phosphorylated RNA Polymerase II engaged in transcription elongation, suggesting an increase in transcription-blocking lesions. In agreement with this conclusion, ongoing RNA synthesis was very significantly reduced by THS exposure. Loss of nucleotide excision repair exacerbated the reduction in RNA synthesis, suggesting that bulky DNA adducts formed by THS are blocks to transcription. The adverse impact on both replication and transcription supports genotoxic stress as a result of THS exposure, with important implications for both cancer and other diseases.
Collapse
Affiliation(s)
- Altaf H. Sarker
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Correspondence: Dr. Altaf H. Sarker, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA, Tel: (510) 486-6113,
| | - Kelly S. Trego
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Weiguo Zhang
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Peyton Jacob
- Department of Medicine, Division of Cardiology, Clinical Pharmacology Program, University of California, San Francisco, CA 94143, USA
| | - Antoine Snijders
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Jian-Hua Mao
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Suzaynn F. Schick
- Department of Medicine, Division of Occupational and Environmental Medicine, University of California, San Francisco, CA 94143, USA
| | - Priscilla K. Cooper
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Bo Hang
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| |
Collapse
|
6
|
Ma B, Villalta PW, Hochalter JB, Stepanov I, Hecht SS. Methyl DNA phosphate adduct formation in lung tumor tissue and adjacent normal tissue of lung cancer patients. Carcinogenesis 2020; 40:1387-1394. [PMID: 30873516 DOI: 10.1093/carcin/bgz053] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 02/25/2019] [Accepted: 03/08/2019] [Indexed: 11/14/2022] Open
Abstract
The formation of methyl DNA adducts is a critical step in carcinogenesis initiated by the exposure to methylating carcinogens. Methyl DNA phosphate adducts, formed by methylation of the oxygen atoms of the DNA phosphate backbone, have been detected in animals treated with methylating carcinogens. However, detection of these adducts in human tissues has not been reported. We developed an ultrasensitive liquid chromatography-nanoelectrospray ionization-high resolution tandem mass spectrometry method for detecting methyl DNA phosphate adducts. Using 50 μg of human lung DNA, a limit of quantitation of two adducts/1010 nucleobases was achieved. Twenty-two structurally unique methyl DNA phosphate adducts were detected in human lung DNA. The adduct levels were measured in both tumor and adjacent normal tissues from 30 patients with lung cancer, including 13 current smokers and 17 current non-smokers, as confirmed by measurements of urinary cotinine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol. Levels of total methyl DNA phosphate adducts in normal lung tissues were higher in smokers than non-smokers, with an average of 13 and 8 adducts/109 nucleobases, respectively. Methyl DNA phosphate adducts were also detected in lung tissues from untreated rats with steady-state levels of 5-7 adducts/109 nucleobases over a period of 70 weeks. This is the first study to report the detection of methyl DNA phosphate adducts in human lung tissues. The results provide new insights toward using these DNA adducts as potential biomarkers to study human exposure to environmental methylating carcinogens.
Collapse
Affiliation(s)
- Bin Ma
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
| | - Peter W Villalta
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
| | | | - Irina Stepanov
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
| | - Stephen S Hecht
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
| |
Collapse
|
7
|
Sarlak S, Lalou C, Amoedo ND, Rossignol R. Metabolic reprogramming by tobacco-specific nitrosamines (TSNAs) in cancer. Semin Cell Dev Biol 2020; 98:154-166. [PMID: 31699542 DOI: 10.1016/j.semcdb.2019.09.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Revised: 08/25/2019] [Accepted: 09/02/2019] [Indexed: 12/21/2022]
Abstract
Metabolic reprogramming is a hallmark of cancer and the link between oncogenes activation, tumor supressors inactivation and bioenergetics modulation is well established. However, numerous carcinogenic environmental factors are responsible for early cancer initiation and their impact on metabolic reprogramming just starts to be deciphered. For instance, it was recently shown that UVB irradiation triggers metabolic reprogramming at the pre-cancer stage with implication for skin cancer detection and therapy. These observations foster the need to study the early changes in tissue metabolism following exposure to other carcinogenic events. According to the International Agency for Research on Cancer (IARC), tobacco smoke is a major class I-carcinogenic environmental factor that contains different carcinogens, but little is known on the impact of tobacco smoke on tissue metabolism and its participation to cancer initiation. In particular, tobacco-specific nitrosamines (TSNAs) play a central role in tobacco-smoke mediated cancer initiation. Here we describe the recent advances that have led to a new hypothesis regarding the link between nitrosamines signaling and metabolic reprogramming in cancer.
Collapse
Affiliation(s)
- Saharnaz Sarlak
- INSERM U1211, 33000 Bordeaux, France; Bordeaux University, 146 rue Léo Saignat, 33000 Bordeaux, France
| | - Claude Lalou
- INSERM U1211, 33000 Bordeaux, France; Bordeaux University, 146 rue Léo Saignat, 33000 Bordeaux, France
| | - Nivea Dias Amoedo
- CELLOMET, Functional Genomics Center (CGFB), 146 rue Léo Saignat, 33000 Bordeaux, France
| | - Rodrigue Rossignol
- INSERM U1211, 33000 Bordeaux, France; Bordeaux University, 146 rue Léo Saignat, 33000 Bordeaux, France; CELLOMET, Functional Genomics Center (CGFB), 146 rue Léo Saignat, 33000 Bordeaux, France.
| |
Collapse
|
8
|
Abstract
Thirdhand smoke (THS), the residual tobacco smoke remaining in the environment after tobacco has been smoked, represents a hidden and underestimated public health hazard. Evidence supports its widespread presence in indoor environments. Exposure to secondhand smoke (SHS), a precursor of THS, has been well documented as a risk factor for human cancers, especially lung cancer. However, the concept of THS as a distinct entity that poses health risks for small children has developed only recently and the associations of THS with cancer risk and other chronic diseases are poorly understood due to limited numbers of studies to date. In this perspective, we mainly summarize all published studies on the genotoxicity and carcinogenic potential of THS exposure. These studies begin to fill the knowledge gap in our understanding of cancer risk of THS. Accumulating data from existing and future studies will help reduce the tobacco-related cancer incidence through changes in lifestyle and tobacco control policies.
Collapse
|
9
|
Kozlovich S, Chen G, Watson CJW, Lazarus P. Prominent Stereoselectivity of NNAL Glucuronidation in Upper Aerodigestive Tract Tissues. Chem Res Toxicol 2019; 32:1689-1698. [PMID: 31307193 DOI: 10.1021/acs.chemrestox.9b00217] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Tobacco specific nitrosamines (TSNAs) are among the most potent carcinogens found in cigarettes and smokeless tobacco products. Decreases in TSNA detoxification, particularly 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), have been associated with tobacco-related cancer incidence. NNK is metabolized by carbonyl reduction to its major carcinogenic metabolite, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), which is detoxified by glucuronidation at the nitrogen within the pyridine ring or at the chiral alcohol to form four glucuronide products: (R)-NNAL-O-Gluc, (S)-NNAL-O-Gluc, (R)-NNAL-N-Gluc, (S)-NNAL-N-Gluc. Stereoselective NNAL-Gluc formation and the relative expression of NNAL-glucuronidating UGTs (1A4, 1A9, 1A10, 2B7, 2B10, 2B17) were analyzed in 39 tissue specimens from the upper aerodigestive tract (esophagus (n = 13), floor of mouth (n = 4), larynx (n = 9), tongue (n = 7), and tonsil (n = 6)). All pooled tissue types preferentially formed (R)-NNAL-O-Gluc in the presence of racemic-NNAL; only esophagus exhibited any detectable formation of (S)-NNAL-O-Gluc. For every tissue type examined, UGT1A10 exhibited the highest relative expression levels among the NNAL-O-glucuronidating UGTs, ranging from 36% (tonsil) to 49% (esophagus), followed by UGT1A9 > UGT2B7 > UGT2B17. UGT1A10 also exhibited similar or higher levels of expression as compared to both NNAL-N-glucuronidating UGTs, 1A4 and 2B10. In a screening of cells expressing individual UGT enzymes, all NNAL glucuronidating UGTs exhibited some level of stereospecific preference for individual NNAL enantiomers, with UGTs 1A10 and 2B17 forming primarily (R)-NNAL-O-Gluc. These data suggest that UGTs 1A10 and 2B17 may be important enzymes in the detoxification of TSNAs like NNK in tissues of the upper aerodigestive tract.
Collapse
Affiliation(s)
- Shannon Kozlovich
- Department of Pharmaceutical Sciences, College of Pharmacy , Washington State University , Spokane Washington 99210 , United States
| | - Gang Chen
- Department of Pharmaceutical Sciences, College of Pharmacy , Washington State University , Spokane Washington 99210 , United States
| | - Christy J W Watson
- Department of Pharmaceutical Sciences, College of Pharmacy , Washington State University , Spokane Washington 99210 , United States
| | - Philip Lazarus
- Department of Pharmaceutical Sciences, College of Pharmacy , Washington State University , Spokane Washington 99210 , United States
| |
Collapse
|
10
|
Wang H, Li X, Zhao G, Xu L, Wang S, Nie M, Hua C, Shang P, Pan L, Zhao J, Qiao L, Liu K, Hu K, Su J, Cai J, Xie F. Analysis of methyl DNA adducts and metabolites in BEAS-2B cells induced by 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone. Toxicol Mech Methods 2019; 29:499-510. [DOI: 10.1080/15376516.2019.1611982] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Huiting Wang
- Key Laboratory of Tobacco Chemistry, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, China
| | - Xiang Li
- Key Laboratory of Tobacco Chemistry, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, China
| | - Ge Zhao
- Key Laboratory of Tobacco Chemistry, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, China
| | - Liangtao Xu
- Key Laboratory of Tobacco Chemistry, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, China
| | - Sheng Wang
- Key Laboratory of Tobacco Chemistry, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, China
| | - Mingxuan Nie
- Zhengzhou Foreign Language School, Zhengzhou, China
| | - Chenfeng Hua
- Key Laboratory of Tobacco Chemistry, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, China
| | - Pingping Shang
- Key Laboratory of Tobacco Chemistry, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, China
| | - Lining Pan
- Key Laboratory of Tobacco Chemistry, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, China
| | - Junwei Zhao
- Key Laboratory of Tobacco Chemistry, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, China
| | - Liangjun Qiao
- Key Laboratory of Tobacco Chemistry, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, China
| | - Kejian Liu
- Key Laboratory of Tobacco Chemistry, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, China
| | - Kai Hu
- Key Laboratory of Tobacco Chemistry, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, China
- Henan University of Chinese Medicine, Zhengzhou, China
| | - Jiakun Su
- China Tobacco Jiangxi Industrial LLC, Nanchang, China
| | - Jibao Cai
- China Tobacco Jiangxi Industrial LLC, Nanchang, China
| | - Fuwei Xie
- Key Laboratory of Tobacco Chemistry, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, China
| |
Collapse
|
11
|
Wilson KA, Holland CD, Wetmore SD. Uncovering a unique approach for damaged DNA replication: A computational investigation of a mutagenic tobacco-derived thymine lesion. Nucleic Acids Res 2019; 47:1871-1879. [PMID: 30605521 PMCID: PMC6393286 DOI: 10.1093/nar/gky1265] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Revised: 12/03/2018] [Accepted: 12/06/2018] [Indexed: 01/01/2023] Open
Abstract
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone is a potent nicotine carcinogen that leads to many DNA lesions, the most persistent being the O2-[4-oxo-4-(3-pyridyl)butyl]thymine adduct (POB-T). Although the experimental mutagenic profile for the minor groove POB-T lesion has been previously reported, the findings are puzzling in terms of the human polymerases involved. Specifically, while pol κ typically replicates minor groove adducts, in vivo studies indicate pol η replicates POB-T despite being known for processing major groove adducts. Our multiscale modeling approach reveals that the canonical (anti) glycosidic orientation of POB-T can fit in the pol κ active site, but only a unique (syn) POB-T conformation is accommodated by pol η. These distinct binding orientations rationalize the differential in vitro mutagenic spectra based on the preferential stabilization of dGTP and dTTP opposite the lesion for pol κ and η, respectively. Overall, by uncovering the first evidence for the replication of a damaged pyrimidine in the syn glycosidic orientation, the current work provides the insight necessary to clarify a discrepancy in the DNA replication literature, expand the biological role of the critical human pol η, and understand the mutational signature in human cancers associated with tobacco exposure.
Collapse
Affiliation(s)
- Katie A Wilson
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta T1K 3M4, Canada
| | - Carl D Holland
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta T1K 3M4, Canada
| | - Stacey D Wetmore
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta T1K 3M4, Canada
| |
Collapse
|
12
|
Ashmore JH, Luo S, Watson CJW, Lazarus P. Carbonyl reduction of NNK by recombinant human lung enzymes: identification of HSD17β12 as the reductase important in (R)-NNAL formation in human lung. Carcinogenesis 2018; 39:1079-1088. [PMID: 29788210 PMCID: PMC6067128 DOI: 10.1093/carcin/bgy065] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 04/26/2018] [Accepted: 05/14/2018] [Indexed: 01/23/2023] Open
Abstract
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is the most abundant and carcinogenic tobacco-specific nitrosamine in tobacco and tobacco smoke. The major metabolic pathway for NNK is carbonyl reduction to form the (R) and (S) enantiomers of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) which, like NNK, is a potent lung carcinogen. The goal of this study was to characterize NNAL enantiomer formation in human lung and identify the enzymes responsible for this activity. While (S)-NNAL was the major enantiomer of NNAL formed in incubations with NNK in lung cytosolic fractions, (R)-NNAL comprised ~60 and ~95% of the total NNAL formed in lung whole cell lysates and microsomes, respectively. In studies examining the role of individual recombinant cytosolic reductase enzymes in lung NNAL enantiomer formation, AKR1C1, AKR1C2, AKR1C3, AKR1C4 and CBR1 all exhibited (S)-NNAL-formation activity. To identify the microsomal enzymes responsible for (R)-NNAL formation, 28 microsomal reductase enzymes were screened for expression by real-time PCR in normal human lung. HSD17β6, HSD17β12, KDSR, NSDHL, RDH10, RDH11 and SDR16C5 were all expressed at levels ≥HSD11β1, the only previously reported microsomal reductase enzyme with NNK-reducing activity, with HSD17β12 the most highly expressed. Of these lung-expressing enzymes, only HSD17β12 exhibited activity against NNK, forming primarily (>95%) (R)-NNAL, a pattern consistent with that observed in lung microsomes. siRNA knock-down of HSD17β12 resulted in significant decreases in (R)-NNAL-formation activity in HEK293 cells. These data suggest that both cytosolic and microsomal enzymes are active against NNK and that HSD17β12 is the major active microsomal reductase that contributes to (R)-NNAL formation in human lung.
Collapse
Affiliation(s)
- Joseph H Ashmore
- Department of Pharmaceutical Sciences, Washington State University, Spokane, WA, USA
| | - Shaman Luo
- Department of Pharmaceutical Sciences, Washington State University, Spokane, WA, USA
- Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Harbin, Heilongjiang, China
| | - Christy J W Watson
- Department of Pharmaceutical Sciences, Washington State University, Spokane, WA, USA
| | - Philip Lazarus
- Department of Pharmaceutical Sciences, Washington State University, Spokane, WA, USA
| |
Collapse
|
13
|
Wu J, Wang P, Li L, You C, Wang Y. Cytotoxic and mutagenic properties of minor-groove O2-alkylthymidine lesions in human cells. J Biol Chem 2018; 293:8638-8644. [PMID: 29685891 DOI: 10.1074/jbc.ra118.003133] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 04/11/2018] [Indexed: 12/17/2022] Open
Abstract
Endogenous metabolism, environmental exposure, and cancer chemotherapy can lead to alkylation of DNA. It has been well documented that, among the different DNA alkylation products, minor-groove O2-alkylthymidine (O2-alkyldT) lesions are inefficiently repaired. In the present study, we examined how seven O2-alkyldT lesions, with the alkyl group being a Me, Et, nPr, iPr, nBu, iBu, or sBu, are recognized by the DNA replication machinery in human cells. We found that the replication bypass efficiencies of these lesions decrease with increasing length of the alkyl chain, and that these lesions induce substantial frequencies of T→A and T→G mutations. Replication experiments using isogenic cells deficient in specific translesion synthesis (TLS) DNA polymerases revealed that the absence of polymerase η or polymerase ζ, but not polymerase κ or polymerase ι, significantly decreased both the bypass efficiencies and the mutation frequencies for those O2-alkyldT lesions carrying a straight-chain alkyl group. Moreover, the mutagenic properties of the O2-alkyldT lesions were influenced by the length and topology of the alkyl chain and by TLS polymerases. Together, our results provide important new knowledge about the cytotoxic and mutagenic properties of O2-alkyldT lesions, and illustrate the roles of TLS polymerases in replicative bypass of these lesions in human cells.
Collapse
Affiliation(s)
- Jun Wu
- From the Department of Chemistry and
| | - Pengcheng Wang
- Environmental Toxicology Graduate Program, University of California, Riverside, California 92521-0403
| | - Lin Li
- From the Department of Chemistry and
| | | | - Yinsheng Wang
- From the Department of Chemistry and .,Environmental Toxicology Graduate Program, University of California, Riverside, California 92521-0403
| |
Collapse
|
14
|
Carlson ES, Upadhyaya P, Villalta PW, Ma B, Hecht SS. Analysis and Identification of 2'-Deoxyadenosine-Derived Adducts in Lung and Liver DNA of F-344 Rats Treated with the Tobacco-Specific Carcinogen 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone and Enantiomers of its Metabolite 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol. Chem Res Toxicol 2018; 31:358-370. [PMID: 29651838 DOI: 10.1021/acs.chemrestox.8b00056] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and its metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) are carcinogenic in animal models and are believed to play an important role in human lung carcinogenesis for cigarette smokers. Cytochrome P450-mediated metabolism of these tobacco-specific nitrosamines produces reactive species that alkylate DNA in the form of pyridyloxobutyl (POB)- or pyridylhydroxybutyl (PHB)-DNA adducts. Understanding the formation mechanism and overall levels of these adducts can potentially enhance cancer prevention methods through the identification of particularly susceptible smokers. Previous studies have identified and measured a panel of POB- and PHB-DNA base adducts of dGuo, dCyd, and Thd; however, dAdo adducts have yet to be determined. In this study, we complete this DNA adduct panel by identifying and quantifying levels of NNK- and NNAL-derived dAdo adducts in vitro and in vivo. To accomplish this, we synthesized standards for expected dAdo-derived DNA adducts and used isotope-dilution LC-ESI+-MS/MS to identify POB adducts formed in vitro from the reaction of 4-(acetoxymethylnitrosamino)-1-(3-pyridyl)-1-butanone (NNKOAc) with calf thymus DNA. Adduct levels were then quantified in lung and liver DNA of rats chronically treated with NNK or NNAL for 50 weeks using similar LC-MS detection methods. The in vitro studies identified N6-POB-dAdo and N1-POB-dIno as products of the reaction of NNKOAc with DNA, which supports our proposed mechanism of formation. Though both N6-dAdo and N1-dIno adducts were found in vitro, only N6-dAdo adducts were found in vivo, implying possible intervention by DNA repair mechanisms. Analogous to previous studies, levels of N6-POB-dAdo and N6-PHB-dAdo varied both with tissue and treatment type. Despite the adduct levels being relatively modest compared to most other POB- and PHB-DNA adducts, they may play a biological role and could be used in future studies as NNK- and NNAL-specific DNA damage biomarkers.
Collapse
Affiliation(s)
- Erik S Carlson
- Masonic Cancer Center , University of Minnesota , 2231 Sixth Street SE , 2-210 CCRB, Minneapolis , Minnesota 55455 , United States.,Department of Pharmacology , University of Minnesota Medical School , 321 Church Street SE , 6-120 Jackson Hall, Minneapolis , Minnesota 55455 , United States
| | - Pramod Upadhyaya
- Masonic Cancer Center , University of Minnesota , 2231 Sixth Street SE , 2-210 CCRB, Minneapolis , Minnesota 55455 , United States
| | - Peter W Villalta
- Masonic Cancer Center , University of Minnesota , 2231 Sixth Street SE , 2-210 CCRB, Minneapolis , Minnesota 55455 , United States
| | - Bin Ma
- Masonic Cancer Center , University of Minnesota , 2231 Sixth Street SE , 2-210 CCRB, Minneapolis , Minnesota 55455 , United States
| | - Stephen S Hecht
- Masonic Cancer Center , University of Minnesota , 2231 Sixth Street SE , 2-210 CCRB, Minneapolis , Minnesota 55455 , United States
| |
Collapse
|
15
|
Ma B, Zarth AT, Carlson ES, Villalta PW, Upadhyaya P, Stepanov I, Hecht SS. Methyl DNA Phosphate Adduct Formation in Rats Treated Chronically with 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone and Enantiomers of Its Metabolite 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol. Chem Res Toxicol 2018; 31:48-57. [PMID: 29131934 PMCID: PMC5770887 DOI: 10.1021/acs.chemrestox.7b00281] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Indexed: 11/29/2022]
Abstract
The tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is a powerful lung carcinogen in animal models and is considered a causative factor for lung cancer in tobacco users. NNK is stereoselectively and reversibly metabolized to 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), which is also a lung carcinogen. Both NNK and NNAL undergo metabolic activation by α-hydroxylation on their methyl groups to form pyridyloxobutyl and pyridylhydroxybutyl DNA base and phosphate adducts, respectively. α-Hydroxylation also occurs on the α-methylene carbons of NNK and NNAL to produce methane diazohydroxide, which reacts with DNA to form methyl DNA base adducts. DNA adducts of NNK and NNAL are important in their mechanisms of carcinogenesis. In this study, we characterized and quantified methyl DNA phosphate adducts in the lung of rats treated with 5 ppm of NNK, (S)-NNAL, or (R)-NNAL in drinking water for 10, 30, 50, and 70 weeks, by using a novel liquid chromatography-nanoelectrospray ionization-high resolution tandem mass spectrometry method. A total of 23, 21, and 22 out of 32 possible methyl DNA phosphate adducts were detected in the lung tissues of rats treated with NNK, (S)-NNAL, and (R)-NNAL, respectively. Levels of the methyl DNA phosphate adducts were 2290-4510, 872-1120, and 763-1430 fmol/mg DNA, accounting for 15-38%, 8%, and 5-9% of the total measured DNA adducts in rats treated with NNK, (S)-NNAL, and (R)-NNAL, respectively. The methyl DNA phosphate adducts characterized in this study further enriched the diversity of DNA adducts formed by NNK and NNAL. These results provide important new data regarding NNK- and NNAL-derived DNA damage and new insights pertinent to future mechanistic and biomonitoring studies of NNK, NNAL, and other chemical methylating agents.
Collapse
Affiliation(s)
- Bin Ma
- Masonic Cancer Center, University of Minnesota, 2231 Sixth Street SE, 2-152 CCRB, Minneapolis, Minnesota 55455, United States
| | - Adam T. Zarth
- Masonic Cancer Center, University of Minnesota, 2231 Sixth Street SE, 2-152 CCRB, Minneapolis, Minnesota 55455, United States
| | - Erik S. Carlson
- Masonic Cancer Center, University of Minnesota, 2231 Sixth Street SE, 2-152 CCRB, Minneapolis, Minnesota 55455, United States
| | - Peter W. Villalta
- Masonic Cancer Center, University of Minnesota, 2231 Sixth Street SE, 2-152 CCRB, Minneapolis, Minnesota 55455, United States
| | - Pramod Upadhyaya
- Masonic Cancer Center, University of Minnesota, 2231 Sixth Street SE, 2-152 CCRB, Minneapolis, Minnesota 55455, United States
| | - Irina Stepanov
- Masonic Cancer Center, University of Minnesota, 2231 Sixth Street SE, 2-152 CCRB, Minneapolis, Minnesota 55455, United States
| | - Stephen S. Hecht
- Masonic Cancer Center, University of Minnesota, 2231 Sixth Street SE, 2-152 CCRB, Minneapolis, Minnesota 55455, United States
| |
Collapse
|
16
|
Prakasha Gowda AS, Spratt TE. Active Site Interactions Impact Phosphoryl Transfer during Replication of Damaged and Undamaged DNA by Escherichia coli DNA Polymerase I. Chem Res Toxicol 2017; 30:2033-2043. [PMID: 29053918 DOI: 10.1021/acs.chemrestox.7b00257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Replicative DNA polymerases are able to discriminate between very similar substrates with high accuracy. One mechanism by which E. coli DNA polymerase I checks for Watson-Crick geometry is through a hydrogen bonding fork between Arg668 and the incoming dNTP and the minor groove of the primer terminus. The importance of the Arg-fork was examined by disrupting it with either a guanine to 3-deazaguanine substitution at the primer terminus or the use of a carbocyclic deoxyribose analog of dUTP. Using thio-substituted dNTPs and differential quench techniques, we determined that when the Arg-fork was disrupted, the rate-limiting step changed from a conformational change to phosphodiester bond formation. This result indicates that Arg668 is involved in the phosphoryl transfer step. We examined the role of the Arg-fork in the replication of four DNA damaged templates, O6-methylguanine (O6-mG), 8-oxo-7,8-dihydroguanine (oxoG), O2-[4-(3-pyridyl)-4-oxobutyl]thymine (O2-POB-T), and N2-[(7S,8R,9S,10R)-7,8,9,10-tetrahydro-8,9,10-trihydroxybenzo[a]pyren-7-yl]-guanine (N2-BP-G). In general, the guanine to 3-deazaguanine substitution caused a decrease in kpol that was proportional to kpol over five orders of magnitude. The linear relationship indicates that the Arg668-fork helps catalyze phosphoryl transfer by the same mechanism with all the substrates. Exceptions to the linear relationship were the incorporations of dTTP opposite G, oxoG, and O6mG, which showed large decreases in kpol, similar to that exhibited by the Watson-Crick base pairs. It was proposed that the incorporation of dTTP opposite G, oxoG, and O6mG occurred via Watson-Crick-like structures.
Collapse
Affiliation(s)
- A S Prakasha Gowda
- Department of Biochemistry and Molecular Biology, Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine , Hershey, Pennsylvania 17033, United States
| | - Thomas E Spratt
- Department of Biochemistry and Molecular Biology, Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine , Hershey, Pennsylvania 17033, United States
| |
Collapse
|
17
|
Hang B, Wang P, Zhao Y, Sarker A, Chenna A, Xia Y, Snijders AM, Mao JH. Adverse Health Effects of Thirdhand Smoke: From Cell to Animal Models. Int J Mol Sci 2017; 18:ijms18050932. [PMID: 28452951 PMCID: PMC5454845 DOI: 10.3390/ijms18050932] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 04/18/2017] [Accepted: 04/24/2017] [Indexed: 11/12/2022] Open
Abstract
The newly identified smoke hazard, thirdhand smoke (THS), has gained public attention in recent years but its health impact and biological effects are largely unknown. THS may be defined by “the four Rs”: tobacco chemicals that remain, react, re-emit, and/or are resuspended long after active smoking has ceased. This review summarizes recent research progress in the effects of THS on genotoxicity, metabolism and early life development using cellular and animal models. We first reported that THS generated in laboratory systems caused significant DNA damage in human cell lines. Our finding that THS significantly induces oxidative base lesions has been confirmed in skin wounds of mice models exposed to THS. THS also induced metabolomic changes in human reproductive cell lines. Furthermore, we demonstrated that early exposure to THS not only negatively impacts body weight in both male and female mice, but also induces persistent changes to immunological parameters in peripheral blood in these mice. These results indicate that THS is genotoxic at realistic experimental doses and that there may be a window of susceptibility for some forms of cellular damage induced by THS.
Collapse
Affiliation(s)
- Bo Hang
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
| | - Pin Wang
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
- Department of Gastroenterology, Drum Tower Clinical Medical School of Nanjing Medical University, Nanjing 210008, China.
| | - Yue Zhao
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
| | - Altaf Sarker
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
| | - Ahmed Chenna
- LabCorp Specialty Testing Group, Monogram Biosciences Inc., South San Francisco, CA 94080, USA.
| | - Yankai Xia
- State Key Laboratory of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, Nanjing 211166, China.
| | - Antoine M Snijders
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
| | - Jian-Hua Mao
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
| |
Collapse
|
18
|
Michel AK, Zarth AT, Upadhyaya P, Hecht SS. Identification of 4-(3-Pyridyl)-4-oxobutyl-2'-deoxycytidine Adducts Formed in the Reaction of DNA with 4-(Acetoxymethylnitrosamino)-1-(3-pyridyl)-1-butanone: A Chemically Activated Form of Tobacco-Specific Carcinogens. ACS OMEGA 2017; 2:1180-1190. [PMID: 28393135 PMCID: PMC5377278 DOI: 10.1021/acsomega.7b00072] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 03/14/2017] [Indexed: 06/07/2023]
Abstract
Metabolic activation of the carcinogenic tobacco-specific nitrosamines 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK, 1) and N'-nitrosonornicotine (NNN, 2) results in the formation of 4-(3-pyridyl)-4-oxobutyl (POB)-DNA adducts, several of which have been previously identified both in vitro and in tissues of laboratory animals treated with NNK or NNN. However, 2'-deoxycytidine adducts formed in this process have been incompletely examined in previous studies. Therefore, in this study we prepared characterized standards for the identification of previously unknown 2'-deoxycytidine and 2'-deoxyuridine adducts that could be produced in these reactions. The formation of these products in reactions of 4-(acetoxymethylnitrosamino)-1-(3-pyridyl)-1-butanone (NNKOAc, 3), a model 4-(3-pyridyl)-4-oxobutylating agent, with DNA was investigated. The major 2'-deoxycytidine adduct, identified as its stable cytosine analogue O2-[4-(3-pyridyl)-4-oxobut-1-yl]-cytosine (12), was O2-[4-(3-pyridyl)-4-oxobut-1-yl]-2'-deoxycytidine (13), whereas lesser amounts of 3-[4-(3-pyridyl)-4-oxobut-1-yl]-2'-deoxycytidine (14) and N4-[4-(3-pyridyl)-4-oxobut-1-yl]-2'-deoxycytidine (15) were also observed. The potential conversion of relatively unstable 2'-deoxycytidine adducts to stable 2'-deoxyuridine adducts by treatment of the adducted DNA with bisulfite was also investigated, but the harsh conditions associated with this approach prevented quantitation. The results of this study provide new validated standards for the study of 4-(3-pyridyl)-4-oxobutylation of DNA, a critical reaction in the carcinogenesis by 1 and 2, and demonstrate the presence of previously unidentified 2'-deoxycytidine adducts in this DNA.
Collapse
Affiliation(s)
- Anna K. Michel
- Masonic
Cancer Center, University of Minnesota, 2231 6th Street SE, Room 2-148 CCRB, Minneapolis, Minnesota 55455, United States
| | - Adam T. Zarth
- Masonic
Cancer Center, University of Minnesota, 2231 6th Street SE, Room 2-148 CCRB, Minneapolis, Minnesota 55455, United States
| | - Pramod Upadhyaya
- Masonic
Cancer Center, University of Minnesota, 2231 6th Street SE, Room 2-148 CCRB, Minneapolis, Minnesota 55455, United States
| | - Stephen S. Hecht
- Masonic
Cancer Center, University of Minnesota, 2231 6th Street SE, Room 2-148 CCRB, Minneapolis, Minnesota 55455, United States
| |
Collapse
|
19
|
Peterson LA. Context Matters: Contribution of Specific DNA Adducts to the Genotoxic Properties of the Tobacco-Specific Nitrosamine NNK. Chem Res Toxicol 2017; 30:420-433. [PMID: 28092943 PMCID: PMC5473167 DOI: 10.1021/acs.chemrestox.6b00386] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is a potent pulmonary carcinogen in laboratory animals. It is classified as a Group 1 human carcinogen by the International Agency for Cancer Research. NNK is bioactivated upon cytochrome P450 catalyzed hydroxylation of the carbon atoms adjacent to the nitrosamino group to both methylating and pyridyloxobutylating agents. Both pathways generate a spectrum of DNA damage that contributes to the overall mutagenic and toxic properties of this compound. NNK is also reduced to form 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), which is also carcinogenic. Like NNK, NNAL requires metabolic activation to DNA alkylating agents. Methyl hydroxylation of NNAL generates pyridylhydroxybutyl DNA adducts, and methylene hydroxylation leads to DNA methyl adducts. The consequence of this complex metabolism is that NNK generates a vast spectrum of DNA damage, any form of which can contribute to the overall carcinogenic properties of this potent pulmonary carcinogen. This Perspective reviews the chemistry and genotoxic properties of the collection of DNA adducts formed from NNK. In addition, it provides evidence that multiple adducts contribute to the overall carcinogenic properties of this chemical. The adduct that contributes to the genotoxic effects of NNK depends on the context, such as the relative amounts of each DNA alkylating pathway occurring in the model system, the levels and genetic variants of key repair enzymes, and the gene targeted for mutation.
Collapse
Affiliation(s)
- Lisa A Peterson
- Masonic Cancer Center and Division of Environmental Health Sciences, University of Minnesota , Minneapolis, Minnesota 55455, United States
| |
Collapse
|
20
|
Penning TM. Aldo-Keto Reductase Regulation by the Nrf2 System: Implications for Stress Response, Chemotherapy Drug Resistance, and Carcinogenesis. Chem Res Toxicol 2017; 30:162-176. [PMID: 27806574 PMCID: PMC5241174 DOI: 10.1021/acs.chemrestox.6b00319] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Human aldo-keto reductases (AKRs) are NAD(P)H-dependent oxidoreductases that convert aldehydes and ketones to primary and secondary alcohols for subsequent conjugation reactions and can be referred to as "phase 1" enzymes. Among all the human genes regulated by the Keap1/Nrf2 pathway, they are consistently the most overexpressed in response to Nrf2 activators. Although these enzymes play clear cytoprotective roles and deal effectively with carbonyl stress, their upregulation by the Keap1/Nrf2 pathway also has a potential dark-side, which can lead to chemotherapeutic drug resistance and the metabolic activation of lung carcinogens (e.g., polycyclic aromatic hydrocarbons). They also play determinant roles in 4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanone metabolism to R- and S-4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanol. The overexpression of AKR genes as components of the "smoking gene" battery raises the issue as to whether this is part of a smoking stress response or acquired susceptibility to lung cancer. Human AKR genes also regulate retinoid, prostaglandin, and steroid hormone metabolism and can regulate the local concentrations of ligands available for nuclear receptors (NRs). The prospect exists that signaling through the Keap1/Nrf2 system can also effect NR signaling, but this has remained largely unexplored. We present the case that chemoprevention through the Keap1/Nrf2 system may be context dependent and that the Nrf2 "dose-response curve" for electrophilic and redox balance may not be monotonic.
Collapse
Affiliation(s)
- Trevor M. Penning
- Center of Excellence in Environmental Toxicology, Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| |
Collapse
|
21
|
Abstract
The tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is a potent pulmonary carcinogen in laboratory animals. It is classified as a Group 1 human carcinogen by the International Agency for Cancer Research. NNK is bioactivated upon cytochrome P450 catalyzed hydroxylation of the carbon atoms adjacent to the nitrosamino group to both methylating and pyridyloxobutylating agents. Both pathways generate a spectrum of DNA damage that contributes to the overall mutagenic and toxic properties of this compound. NNK is also reduced to form 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), which is also carcinogenic. Like NNK, NNAL requires metabolic activation to DNA alkylating agents. Methyl hydroxylation of NNAL generates pyridylhydroxybutyl DNA adducts, and methylene hydroxylation leads to DNA methyl adducts. The consequence of this complex metabolism is that NNK generates a vast spectrum of DNA damage, any form of which can contribute to the overall carcinogenic properties of this potent pulmonary carcinogen. This Perspective reviews the chemistry and genotoxic properties of the collection of DNA adducts formed from NNK. In addition, it provides evidence that multiple adducts contribute to the overall carcinogenic properties of this chemical. The adduct that contributes to the genotoxic effects of NNK depends on the context, such as the relative amounts of each DNA alkylating pathway occurring in the model system, the levels and genetic variants of key repair enzymes, and the gene targeted for mutation.
Collapse
Affiliation(s)
- Lisa A Peterson
- Masonic Cancer Center and Division of Environmental Health Sciences, University of Minnesota , Minneapolis, Minnesota 55455, United States
| |
Collapse
|
22
|
Ma B, Ruszczak C, Jain V, Khariwala SS, Lindgren B, Hatsukami DK, Stepanov I. Optimized Liquid Chromatography Nanoelectrospray-High-Resolution Tandem Mass Spectrometry Method for the Analysis of 4-Hydroxy-1-(3-pyridyl)-1-butanone-Releasing DNA Adducts in Human Oral Cells. Chem Res Toxicol 2016; 29:1849-1856. [PMID: 27618873 PMCID: PMC5148665 DOI: 10.1021/acs.chemrestox.6b00254] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Metabolic activation of the carcinogenic tobacco-specific N-nitrosamines leads to the formation of 4-hydroxy-1-(3-pyridyl)-1-butanone (HPB)-releasing DNA adducts. We recently developed a liquid chromatography (LC)-tandem mass spectrometry (MS/MS) method for the analysis of HPB-releasing DNA adducts in human oral cells. However, given the limited amounts of DNA that can be extracted from oral cells, higher sensitivity and selectivity are required for the reliable analysis of these adducts in future studies. We have developed a new sensitive LC-nanoelectrospray ionization-high-resolution MS/MS method for the analysis of HPB-releasing DNA adducts in oral cells. A new procedure was also developed for guanine analysis by LC-MS/MS. The detection limit of the developed assay is 5 amol, and the limit of quantitation is 0.35 fmol HPB on-column, starting with 50 pg of DNA. The method was tested by analyzing oral samples from 65 smokers, including 30 head and neck squamous cell carcinoma (HNSCC) patients and 35 cancer-free controls. In all smokers, the levels of HPB-releasing DNA adducts averaged 6.22 ± 16.18 pmol/mg DNA, with significant interindividual variation being consistent with previous reports. The median HPB-releasing DNA adduct level was 6.6 times greater for those with HNSCC than for smokers without HNSCC (p = 0.002). The developed highly sensitive and selective method is a valuable tool for future measurement of HPB-releasing DNA adducts in tobacco users, which can potentially provide critical insights for the identification of individuals at risk for cancer.
Collapse
Affiliation(s)
- Bin Ma
- Masonic Cancer Center, University of Minnesota
| | | | - Vipin Jain
- Masonic Cancer Center, University of Minnesota
| | - Samir S. Khariwala
- Masonic Cancer Center, University of Minnesota
- Department of Otolaryngology, Head and Neck Surgery, University of Minnesota
| | | | | | - Irina Stepanov
- Masonic Cancer Center, University of Minnesota
- Division of Environmental Health Sciences, University of Minnesota
| |
Collapse
|
23
|
Williams NL, Wang P, Wang Y. Replicative Bypass of O 2-Alkylthymidine Lesions in Vitro. Chem Res Toxicol 2016; 29:1755-1761. [PMID: 27611246 DOI: 10.1021/acs.chemrestox.6b00252] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
DNA alkylation represents a major type of DNA damage and is generally unavoidable due to ubiquitous exposure to various exogenous and endogenous sources of alkylating agents. Among the alkylated DNA lesions, O2-alkylthymidines (O2-alkyldT) are known to be persistent and poorly repaired in mammalian systems and have been shown to accumulate in the esophagus, lung, and liver tissue of rats treated with tobacco-specific N-nitrosamines, i.e., 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N'-nitrosonornicotine (NNN). In this study, we assessed the replicative bypass of a comprehensive set of O2-alkyldT lesions, with the alkyl group being a Me, Et, nPr, iPr, nBu, iBu, or sBu, in template DNA by conducting primer extension assays with the use of major translesion synthesis DNA polymerases. The results showed that human Pol η and, to a lesser degree, human Pol κ, but not human polymerase ι or yeast polymerase ζ, were capable of bypassing all O2-alkyldT lesions and extending the primer to generate full-length replication products. Data from steady-state kinetic measurements showed that human Pol η exhibited high frequencies of misincorporation of dCMP opposite those O2-alkyldT lesions bearing a longer straight-chain alkyl group. However, the nucleotide misincorporation opposite branched-chain lesions was not selective, with dCMP, dGMP, and dTMP being inserted at similar efficiencies, though the total frequencies of nucleotide misincorporation opposite the branched-chain lesions differed and followed the order of O2-iPrdT > O2-iBudT > O2-sBudT. Together, the results from the present study provided important knowledge about the effects of the length and structure of the alkyl group in the O2-alkyldT lesions on the fidelity and efficiency of DNA replication mediated by human Pol η.
Collapse
Affiliation(s)
- Nicole L Williams
- Environmental Toxicology Graduate Program and ‡Department of Chemistry, University of California , Riverside, California 92521-0403, United States
| | - Pengcheng Wang
- Environmental Toxicology Graduate Program and ‡Department of Chemistry, University of California , Riverside, California 92521-0403, United States
| | - Yinsheng Wang
- Environmental Toxicology Graduate Program and ‡Department of Chemistry, University of California , Riverside, California 92521-0403, United States
| |
Collapse
|
24
|
Guo J, Turesky RJ. Human Biomonitoring of DNA Adducts by Ion Trap Multistage Mass Spectrometry. ACTA ACUST UNITED AC 2016; 66:7.24.1-7.24.25. [PMID: 27584705 DOI: 10.1002/cpnc.12] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Humans are continuously exposed to hazardous chemicals in the environment. These chemicals or their electrophilic metabolites can form adducts with genomic DNA, which can lead to mutations and the initiation of cancer. The identification of DNA adducts is required for understanding exposure and the etiological role of a genotoxic chemical in cancer risk. The analytical chemist is confronted with a great challenge because the levels of DNA adducts generally occur at <1 adduct per 10(7) nucleotides, and the amount of tissue available for measurement is limited. Ion trap mass spectrometry has emerged as an important technique to screen for DNA adducts because of the high level sensitivity and selectivity, particularly when employing multi-stage scanning (MS(n) ). The product ion spectra provide rich structural information and corroborate the adduct identities even at trace levels in human tissues. Ion trap technology represents a significant advance in measuring DNA adducts in humans. © 2016 by John Wiley & Sons, Inc.
Collapse
Affiliation(s)
- Jingshu Guo
- Masonic Cancer Center and Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota
| | - Robert J Turesky
- Masonic Cancer Center and Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota
| |
Collapse
|
25
|
Re E, Tong M, de la Monte SM. Tobacco Nitrosamine Exposures Contribute to Fetal Alcohol Spectrum Disorder Associated Cerebellar Dysgenesis. ACTA ACUST UNITED AC 2016; 8:10-21. [PMID: 29201262 PMCID: PMC5711469 DOI: 10.5539/ijb.v8n3p10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Variability in the phenotypic features and severity of fetal alcohol spectrum disorder (FASD) is not fully linked to alcohol dose. We hypothesize that FASD-type neurodevelopmental abnormalities may be caused by exposures to the tobacco-specific nitrosamine, NNK, since a high percentage of pregnant women who drink also smoke. In vitro experiments using PNET2 human cerebellar neuronal cultures examined ethanol and NNK effects on viability and mitochondrial function. Early postnatal rat cerebellar slice cultures were used to examine effects of ethanol and NNK on cerebellar histology and neuroglial and stress protein expression. Ethanol (50 mM) decreased viability and ATP content and increased mitochondrial mass, while NNK (100 μM or higher) selectively inhibited mitochondrial function. The slice culture studies demonstrated striking adverse effects of ethanol, NNK and ethanol+NNK exposures manifested by architectural disorganization of the cortex with relative reductions of internal granule cells, increases in external granule cells, and loss of Purkinje cells. Ethanol, NNK, and ethanol+NNK inhibited expression of choline acetyltransferase (ChAT) and acetylcholinesterase (AChE), and increased levels of 4-hydroxynonenal (HNE). In addition, ethanol increased activated Caspase 3, NNK decreased tau and phospho-tau, and ethanol+NNK inhibited expression of Aspartyl-β-hydroxylase (ASPH), which mediates neuronal migration. In conclusion, ethanol and NNK were shown to exert independent but overlapping adverse effects on cerebellar cortical development, neuronal viability, function, and neuroglial protein expression. These findings support our hypothesis that NNK exposures via tobacco smoking in pregnancy can contribute to FASD-associated neurodevelopmental abnormalities.
Collapse
Affiliation(s)
- Edward Re
- Warren Alpert Medical School of Brown University, Providence, RI
| | - Ming Tong
- Department of Medicine, Division of Gastroenterology, and Liver Research Center Rhode Island Hospital, Providence, RI.,Warren Alpert Medical School of Brown University, Providence, RI
| | - Suzanne M de la Monte
- Department of Medicine, Division of Gastroenterology, and Liver Research Center Rhode Island Hospital, Providence, RI.,Departments of Pathology, Neurology, and Neurosurgery, and the Division of Neuropathology, Rhode Island Hospital, Providence, RI.,Warren Alpert Medical School of Brown University, Providence, RI
| |
Collapse
|
26
|
Baillie TA, Dalvie D, Rietjens IMCM, Cyrus Khojasteh S. Biotransformation and bioactivation reactions – 2015 literature highlights. Drug Metab Rev 2016; 48:113-38. [DOI: 10.1080/03602532.2016.1195404] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
| | - Deepak Dalvie
- Pfizer Global Research and Development, La Jolla Laboratories, San Diego, CA, USA
| | | | - S. Cyrus Khojasteh
- Department of Drug Metabolism and Pharmacokinetics, Genentech, 1 DNA Way, South San Francisco, CA, USA
| |
Collapse
|
27
|
Chen G, Luo S, Kozlovich S, Lazarus P. Association between Glucuronidation Genotypes and Urinary NNAL Metabolic Phenotypes in Smokers. Cancer Epidemiol Biomarkers Prev 2016; 25:1175-1184. [PMID: 27197298 DOI: 10.1158/1055-9965.epi-15-1245] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 04/27/2016] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND The most abundant and potent carcinogenic tobacco-specific nitrosamine in tobacco and tobacco smoke is 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). In vivo, NNK is rapidly metabolized to both the (R)- and (S)-enantiomers of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), which possesses similar carcinogenic properties as NNK. The major detoxification pathway for both NNAL enantiomers is glucuronidation by UDP-glucuronosyltransferase (UGT) enzymes including UGT2B10 and UGT2B17. The goal of the present study was to directly examine the role of UGT genotypes on urinary levels of NNAL glucuronides in smokers. METHODS NNAL-N-Gluc, (R)-NNAL-O-Gluc, (S)-NNAL-O-Gluc, and free NNAL were simultaneously and directly quantified in the urine of smokers by LC/MS analysis. Genotypes were determined by TaqMan assay using genomic DNA. RESULTS The functional knockout polymorphism in the UGT2B10 gene at codon 67 (Asp>Tyr) was significantly (P < 0.0001) associated with a 93% decrease in creatinine-adjusted NNAL-N-Gluc. The polymorphic whole-gene deletion of the UGT2B17 gene was associated with significant (P = 0.0048) decreases in the levels of creatinine-adjusted (R)-NNAL-O-Gluc, with a 32% decrease in the levels of urinary (R)-NNAL-O-Gluc/(S)-NNAL-O-Gluc among subjects with the UGT2B17 (*2/*2) genotype as compared to subjects with the UGT2B17 (*1/*1) genotype. CONCLUSIONS These results suggest that functional polymorphisms in UGT2B10 and UGT2B17 are associated with a reduced detoxification capacity against NNAL and may therefore affect individual cancer risk upon exposure to tobacco. IMPACT This is the first report to clearly demonstrate strong genotype-phenotype associations between both the UGT2B10 codon 67 Asp<Tyr genotype and urinary NNAL-N-Gluc levels and between the UGT2B17 copy number variant and urinary (R)-NNAL-O-Gluc levels in smokers. Cancer Epidemiol Biomarkers Prev; 25(7); 1175-84. ©2016 AACR.
Collapse
Affiliation(s)
- Gang Chen
- Department of Pharmaceutical Sciences, College of Pharmacy, Washington State University, Spokane WA 99210
| | - Shaman Luo
- Department of Pharmaceutical Sciences, College of Pharmacy, Washington State University, Spokane WA 99210.,Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Harbin, Heilongjiang, China
| | - Shannon Kozlovich
- Department of Pharmaceutical Sciences, College of Pharmacy, Washington State University, Spokane WA 99210
| | - Philip Lazarus
- Department of Pharmaceutical Sciences, College of Pharmacy, Washington State University, Spokane WA 99210
| |
Collapse
|
28
|
Zabala V, Silbermann E, Re E, Andreani T, Tong M, Ramirez T, Gundogan F, de la Monte SM. Potential Co-Factor Role of Tobacco Specific Nitrosamine Exposures in the Pathogenesis of Fetal Alcohol Spectrum Disorder. GYNECOLOGY AND OBSTETRICS RESEARCH : OPEN JOURNAL 2016; 2:112-125. [PMID: 28845454 PMCID: PMC5570438 DOI: 10.17140/goroj-2-125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Cerebellar developmental abnormalities in Fetal Alcohol Spectrum Disorder (FASD) are linked to impairments in insulin signaling. However, co-morbid alcohol and tobacco abuses during pregnancy are common. Since smoking leads to tobacco specific Nitrosamine (NNK) exposures which have been shown to cause brain insulin resistance, we hypothesized that neurodevelopmental abnormalities in FASD could be mediated by ethanol and/or NNK. METHODS Long Evans rat pups were intraperitoneal (IP) administered ethanol (2 g/kg) on postnatal days (P) 2, 4, 6 and/or NNK (2 mg/kg) on P3, P5, and P7 to simulate third trimester human exposures. The Cerebellar function, histology, insulin and Insulin-like Growth Factor (IGF) signaling, and neuroglial protein expression were assessed. RESULTS Ethanol, NNK and ethanol+NNK groups had significant impairments in motor function (rotarod tests), abnormalities in cerebellar structure (Purkinje cell loss, simplification and irregularity of folia, and altered white matter), signaling through the insulin and IGF-1 receptors, IRS-1, Akt and GSK-3β, and reduced expression of several important neuroglial proteins. Despite similar functional effects, the mechanisms and severity of NNK and ethanol+NNK induced alterations in cerebellar protein expression differed from those of ethanol. CONCLUSIONS Ethanol and NNK exert independent but overlapping adverse effects on cerebellar development, function, insulin signaling through cell survival, plasticity, metabolic pathways, and neuroglial protein expression. The results support the hypothesis that tobacco smoke exposure can serve as a co-factor mediating long-term effects on brain structure and function in FASD.
Collapse
Affiliation(s)
- Valerie Zabala
- Molecular Pharmacology and Physiology Graduate Program, Brown University, Providence, RI, USA
| | | | - Edward Re
- Alpert Medical School of Brown University, Providence, RI, USA
| | - Tomas Andreani
- Graduate Program in Neuroscience, Northwestern University, Chicago, IL, USA
| | - Ming Tong
- Liver Research Center, Division of Gastroenterology and Department of Medicine, Rhode Island Hospital and the Alpert Medical School of Brown University, Providence, RI, USA
| | | | - Fusun Gundogan
- Department of Pathology, Women and Infants Hospital of Rhode Island, Alpert Medical School of Brown University, Providence, RI, USA
| | - Suzanne M. de la Monte
- Departments of Neurology, Neurosurgery, and Pathology, Rhode Island Hospital and the Alpert Medical School of Brown University, Providence, RI, USA
| |
Collapse
|
29
|
Gowda ASP, Spratt TE. DNA Polymerases η and ζ Combine to Bypass O(2)-[4-(3-Pyridyl)-4-oxobutyl]thymine, a DNA Adduct Formed from Tobacco Carcinogens. Chem Res Toxicol 2016; 29:303-16. [PMID: 26868090 PMCID: PMC5081176 DOI: 10.1021/acs.chemrestox.5b00468] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N'-nitrosonornicotine (NNN) are important human carcinogens in tobacco products. They are metabolized to produce a variety 4-(3-pyridyl)-4-oxobutyl (POB) DNA adducts including O(2)-[4-(3-pyridyl)-4-oxobut-1-yl]thymidine (O(2)-POB-dT), the most abundant POB adduct in NNK- and NNN-treated rodents. To evaluate the mutagenic properties of O(2)-POB-dT, we measured the rate of insertion of dNTPs opposite and extension past O(2)-POB-dT and O(2)-Me-dT by purified human DNA polymerases η, κ, ι, and yeast polymerase ζ in vitro. Under conditions of polymerase in excess, polymerase η was most effective at the insertion of dNTPs opposite O(2)-alkyl-dTs. The time courses were biphasic suggesting the formation of inactive DNA-polymerase complexes. The kpol parameter was reduced approximately 100-fold in the presence of the adduct for pol η, κ, and ι. Pol η was the most reactive polymerase for the adducts due to a higher burst amplitude. For all three polymerases, the nucleotide preference was dATP > dTTP ≫ dGTP and dCTP. Yeast pol ζ was most effective in bypassing the adducts; the kcat/Km values were reduced only 3-fold in the presence of the adducts. The identity of the nucleotide opposite the O(2)-alkyl-dT did not significantly affect the ability of pol ζ to bypass the adducts. The data support a model in which pol η inserts ATP or dTTP opposite O(2)-POB-dT, and then, pol ζ extends past the adduct.
Collapse
Affiliation(s)
- A. S. Prakasha Gowda
- Department of Biochemistry and Molecular Biology Penn State Hershey Cancer Institute, Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033, United States
| | - Thomas E. Spratt
- Department of Biochemistry and Molecular Biology Penn State Hershey Cancer Institute, Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033, United States
| |
Collapse
|
30
|
Ma B, Jing M, Villalta PW, Kapphahn RJ, Montezuma SR, Ferrington DA, Stepanov I. Simultaneous determination of 8-oxo-2'-deoxyguanosine and 8-oxo-2'-deoxyadenosine in human retinal DNA by liquid chromatography nanoelectrospray-tandem mass spectrometry. Sci Rep 2016; 6:22375. [PMID: 26979577 PMCID: PMC4793187 DOI: 10.1038/srep22375] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 02/01/2016] [Indexed: 01/29/2023] Open
Abstract
Age-related macular degeneration (AMD) is the leading cause of blindness among older adults in the developed world. Oxidative damage to mitochondrial DNA (mtDNA) in the retinal pigment epithelium (RPE) may play a key role in AMD. Measurement of oxidative DNA lesions such as 8-oxo-2'-deoxyguanosine (8-oxo-dG) and 8-oxo-2'-deoxyadenosine (8-oxo-dA) in diseased RPE could provide important insights into the mechanism of AMD development. We have developed a liquid chromatography-nanoelectrospray ionization-tandem mass spectrometry method for simultaneous analysis of 8-oxo-dG and 8-oxo-dA in human retinal DNA. The developed method was applied to the analysis of retinal DNA from 5 donors with AMD and 5 control donors without AMD. In mtDNA, the levels of 8-oxo-dG in controls and AMD donors averaged 170 and 188, and 8-oxo-dA averaged 11 and 17 adducts per 10(6) bases, respectively. In nuclear DNA, the levels of 8-oxo-dG in controls and AMD donors averaged 0.54 and 0.96, and 8-oxo-dA averaged 0.04 and 0.05 adducts per 10(6) bases, respectively. This highly sensitive method allows for the measurement of both adducts in very small amounts of DNA and can be used in future studies investigating the pathophysiological role of 8-oxo-dG and 8-oxo-dA in AMD and other oxidative damage-related diseases in humans.
Collapse
Affiliation(s)
- Bin Ma
- Masonic Cancer Center, University of Minnesota, Mayo Mail Code 806, 420 Delaware Street SE, Minneapolis, Minnesota 55455, United States
| | - Meng Jing
- Masonic Cancer Center, University of Minnesota, Mayo Mail Code 806, 420 Delaware Street SE, Minneapolis, Minnesota 55455, United States
| | - Peter W. Villalta
- Masonic Cancer Center, University of Minnesota, Mayo Mail Code 806, 420 Delaware Street SE, Minneapolis, Minnesota 55455, United States
| | - Rebecca J. Kapphahn
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Mayo Mail Code 493, 420 Delaware Street SE, Minneapolis, Minnesota 55455, United States
| | - Sandra R. Montezuma
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Mayo Mail Code 493, 420 Delaware Street SE, Minneapolis, Minnesota 55455, United States
| | - Deborah A. Ferrington
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Mayo Mail Code 493, 420 Delaware Street SE, Minneapolis, Minnesota 55455, United States
| | - Irina Stepanov
- Masonic Cancer Center, University of Minnesota, Mayo Mail Code 806, 420 Delaware Street SE, Minneapolis, Minnesota 55455, United States
- Division of Environmental Health Sciences, University of Minnesota, Mayo Mail Code 807, 420 Delaware Street SE, Minneapolis, Minnesota 55455, United States
| |
Collapse
|
31
|
Abstract
Among the most potent carcinogens in tobacco are the tobacco-specific nitrosamines (TSNAs), with 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) being the most potent as well as one of the most abundant. NNK is extensively metabolized to the equally carcinogenic 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL). Of the two NNAL enantiomers, (S)-NNAL not only appears to be preferentially glucuronidated and excreted in humans but also exhibits higher stereoselective tissue retention in mice and humans and has been shown to be more carcinogenic in mice than its (R) counterpart. Due to the differential carcinogenic potential of the NNAL enantiomers, it is increasingly important to know which UGT enzyme targets the specific NNAL enantiomers for glucuronidation. To examine this, a chiral separation method was developed to isolate enantiomerically pure (S)- and (R)-NNAL. Comparison of NNAL glucuronides (NNAL-Glucs) formed in reactions of UGT2B7-, UGT2B17-, UGT1A9-, and UGT2B10-overexpressing cell microsomes with pure NNAL enantiomers showed large differences in kinetics for (S)- versus (R)-NNAL, indicating varying levels of enantiomeric preference for each enzyme. UGT2B17 preferentially formed (R)-NNAL-O-Gluc, and UGT2B7 preferentially formed (S)-NNAL-O-Gluc. When human liver microsomes (HLM) were independently incubated with each NNAL enantiomer, the ratio of (R)-NNAL-O-Gluc to (S)-NNAL-O-Gluc formation in HLM from subjects exhibiting the homozygous deletion UGT2B17 (*2/*2) genotype was significantly lower (p = 0.012) than that with HLM from wild-type (*1/*1) subjects. There was a significant trend (p = 0.015) toward a decreased (R)-NNAL-O-Gluc/(S)-NNAL-O-Gluc ratio as the copy number of the UGT2B17*2 deletion allele increased. These data demonstrate that variations in the expression or activity of specific UGTs may affect the clearance of specific NNAL enantiomers known to induce tobacco-related cancers.
Collapse
Affiliation(s)
- Shannon Kozlovich
- Department of Pharmaceutical Sciences, College of Pharmacy, Washington State University, Spokane WA 99210
| | - Gang Chen
- Department of Pharmaceutical Sciences, College of Pharmacy, Washington State University, Spokane WA 99210
| | - Philip Lazarus
- Department of Pharmaceutical Sciences, College of Pharmacy, Washington State University, Spokane WA 99210
| |
Collapse
|
32
|
Feng M, Zhang H, Cao B, Liu S, Mao J, Zhang Q. Effects of 8-methoxypsoralen on the metabolism of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone in mice. Drug Metab Pharmacokinet 2015. [PMID: 26210672 DOI: 10.1016/j.dmpk.2015.06.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
8-Methoxypsoralen (8-MOP) is a well established drug in the treatment of various skin diseases. Pretreatment of mice with 8-MOP before administration of 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) significantly reduced the incidence of NNK-induced tumor. The present study was designed to evaluate the in vivo effects of 8-MOP on the bioactivation of NNK in mice. Decrease in the α-hydroxylation of NNK in mouse blood and tissues was observed as the most pronounced effect of 8-MOP. The catalytic property of cytochrome P450 2A5 (CYP2A5) enzyme in mice was determined by the coumarin 7-hydroxylation reaction, suggesting that 8-MOP produced remarkable inhibition on CYP2A5 in female C57BL/6 mice. These results implied that 8-MOP could prevent NNK-induced mutagenesis and tumorigenesis in mice through the inhibition of NNK α-hydroxylation, which may be achieved through the effect of 8-MOP on the bioactivities of CYP2A5.
Collapse
Affiliation(s)
- Mingfei Feng
- Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou 450001, China
| | - Hongtu Zhang
- Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
| | - Baojun Cao
- Tobacco Production Technology Center, Bijie Tobacco Company of Guizhou Province, Bijie 551700, China
| | - Shuaidong Liu
- Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou 450001, China
| | - Jian Mao
- Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou 450001, China.
| | - Qidong Zhang
- Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou 450001, China.
| |
Collapse
|
33
|
Balbo S, Johnson CS, Kovi RC, James-Yi SA, O'Sullivan MG, Wang M, Le CT, Khariwala SS, Upadhyaya P, Hecht SS. Carcinogenicity and DNA adduct formation of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone and enantiomers of its metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol in F-344 rats. Carcinogenesis 2014; 35:2798-806. [PMID: 25269804 PMCID: PMC4247520 DOI: 10.1093/carcin/bgu204] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Revised: 08/19/2014] [Accepted: 08/28/2014] [Indexed: 12/28/2022] Open
Abstract
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is metabolized to enantiomers of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), found in the urine of virtually all people exposed to tobacco products. We assessed the carcinogenicity in male F-344 rats of (R)-NNAL (5 ppm in drinking water), (S)-NNAL (5 ppm), NNK (5 ppm) and racemic NNAL (10 ppm) and analyzed DNA adduct formation in lung and pancreas of these rats after 10, 30, 50 and 70 weeks of treatment. All test compounds induced a high incidence of lung tumors, both adenomas and carcinomas. NNK and racemic NNAL were most potent; (R)-NNAL and (S)-NNAL had equivalent activity. Metastasis was observed from primary pulmonary carcinomas to the pancreas, particularly in the racemic NNAL group. DNA adducts analyzed were O (2)-[4-(3-pyridyl)-4-oxobut-1-yl]thymidine (O (2)-POB-dThd), 7-[4-(3-pyridyl)-4-oxobut-1-yl]guanine(7-POB-Gua),O (6)-[4-(3-pyridyl)-4-oxobut-1-yl]deoxyguanosine(O (6)-POB-dGuo),the 4-(3-pyridyl)-4-hydroxybut-1-yl(PHB)adductsO (2)-PHB-dThd and 7-PHB-Gua, O (6)-methylguanine (O (6)-Me-Gua) and 4-hydroxy-1-(3-pyridyl)-1-butanone (HPB)-releasing adducts. Adduct levels significantly decreased with time in the lungs of rats treated with NNK. Pulmonary POB-DNA adducts and O (6)-Me-Gua were similar in rats treated with NNK and (S)-NNAL; both were significantly greater than in the (R)-NNAL rats. In contrast, pulmonary PHB-DNA adduct levels were greatest in the rats treated with (R)-NNAL. Total pulmonary DNA adduct levels were similar in (S)-NNAL and (R)-NNAL rats. Similar trends were observed for DNA adducts in the pancreas, but adduct levels were significantly lower than in the lung. The results of this study clearly demonstrate the potent pulmonary carcinogenicity of both enantiomers of NNAL in rats and provide important new information regarding DNA damage by these compounds in lung and pancreas.
Collapse
Affiliation(s)
- Silvia Balbo
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Charles S Johnson
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Ramesh C Kovi
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Sandra A James-Yi
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | | | - Mingyao Wang
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Chap T Le
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Samir S Khariwala
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Pramod Upadhyaya
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Stephen S Hecht
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| |
Collapse
|
34
|
Narayanapillai SC, Balbo S, Leitzman P, Grill AE, Upadhyaya P, Shaik AA, Zhou B, O'Sullivan MG, Peterson LA, Lu J, Hecht SS, Xing C. Dihydromethysticin from kava blocks tobacco carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone-induced lung tumorigenesis and differentially reduces DNA damage in A/J mice. Carcinogenesis 2014; 35:2365-72. [PMID: 25053626 PMCID: PMC4178470 DOI: 10.1093/carcin/bgu149] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 06/28/2014] [Accepted: 07/09/2014] [Indexed: 11/14/2022] Open
Abstract
We have previously shown that kava and its flavokavain-free Fraction B completely blocked 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced lung tumorigenesis in A/J mice with a preferential reduction in NNK-induced O (6)-methylguanine (O (6)-mG). In this study, we first identified natural (+)-dihydromethysticin (DHM) as a lead compound through evaluating the in vivo efficacy of five major compounds in Fraction B on reducing O (6)-mG in lung tissues. (+)-DHM demonstrated outstanding chemopreventive activity against NNK-induced lung tumorigenesis in A/J mice with 97% reduction of adenoma multiplicity at a dose of 0.05mg/g of diet (50 ppm). Synthetic (±)-DHM was equally effective as the natural (+)-DHM in these bioassays while a structurally similar analog, (+)-dihydrokavain (DHK), was completely inactive, revealing a sharp in vivo structure-activity relationship. Analyses of an expanded panel of NNK-induced DNA adducts revealed that DHM reduced a subset of DNA adducts in lung tissues derived from 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL, the active metabolite of NNK). Preliminary 17-week safety studies of DHM in A/J mice at a dose of 0.5mg/g of diet (at least 10× its minimum effective dose) revealed no adverse effects, suggesting that DHM is likely free of kava's hepatotoxic risk. These results demonstrate the outstanding efficacy and promising safety margin of DHM in preventing NNK-induced lung tumorigenesis in A/J mice, with a unique mechanism of action and high target specificity.
Collapse
Affiliation(s)
| | - Silvia Balbo
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Pablo Leitzman
- Department of Medicinal Chemistry, College of Pharmacy and
| | - Alex E Grill
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Pramod Upadhyaya
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Ahmad Ali Shaik
- Department of Medicinal Chemistry, College of Pharmacy and Present address: Department of Chemistry, The University of Toledo, Toledo, OH 43606, USA
| | - Bo Zhou
- Department of Medicinal Chemistry, College of Pharmacy and
| | - M Gerard O'Sullivan
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA, Department of Veterinary Population Medicine, University of Minnesota, St Paul, MN 55108, USA
| | - Lisa A Peterson
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA, Division of Environmental Health Sciences, University of Minnesota, MN 55455, USA and
| | - Junxuan Lu
- Department of Biomedical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX 79106, USA
| | - Stephen S Hecht
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA,
| | - Chengguo Xing
- Department of Medicinal Chemistry, College of Pharmacy and
| |
Collapse
|
35
|
Ma B, Villalta PW, Balbo S, Stepanov I. Analysis of a malondialdehyde-deoxyguanosine adduct in human leukocyte DNA by liquid chromatography nanoelectrospray-high-resolution tandem mass spectrometry. Chem Res Toxicol 2014; 27:1829-36. [PMID: 25181548 PMCID: PMC4203394 DOI: 10.1021/tx5002699] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Malondialdehyde
(MDA), an endogenous genotoxic product formed upon
lipid peroxidation and prostaglandin biosynthesis, can react with
DNA to form stable adducts. These adducts may contribute to the development
of such inflammation-mediated diseases as cancer and cardiovascular
and neurodegenerative diseases. The predominant MDA-derived DNA adduct
formed under physiological conditions is 3-(2-deoxy-β-d-erythro-pentafuranosyl)pyrimido[1,2-α]purin-10(3H)-one deoxyguanosine (M1dG). In this study, we developed
a novel liquid chromatography (LC)–nanoelectrospray ionization
(NSI)–high-resolution tandem mass spectrometry (HRMS/MS) method
for the analysis of M1dG in human leukocyte DNA. After
enzymatic hydrolysis of DNA, M1dG and the added internal
standard [13C3]M1dG were reduced
to their 5,6-dihydro derivatives by addition of sodium borohydride
to the hydrolysate and purified by solid-phase extraction and column
chromatography. The 5,6-dihydro derivatives in the purified samples
were analyzed by LC–NSI–HRMS/MS using higher-energy
collisional dissociation (HCD) fragmentation, isolation widths of
1 Da for both the analyte and internal standard, and a resolution
of 50 000. The detection limit of the developed method is 5
amol on-column, and the limit of quantitation is 0.125 fmol/mg DNA
starting with 200 μg of DNA. Method accuracy and precision were
characterized. The developed method was further applied to the analysis
of leukocyte DNA from 50 human subjects. M1dG was detected
in all samples and ranged from 0.132 to 275 fmol/mg DNA, or 0.004
to 9.15 adducts per 108 bases. This unique and highly sensitive
HRMS/MS-based method can be used in future studies investigating the
pathophysiological role of M1dG in human diseases.
Collapse
Affiliation(s)
- Bin Ma
- Masonic Cancer Center and ‡Division of Environmental Health Sciences, University of Minnesota , Mayo Mail Code 806, 420 Delaware Street South East, Minneapolis, Minnesota 55455, United States
| | | | | | | |
Collapse
|
36
|
Jing M, Wang Y, Upadhyaya P, Jain V, Yuan JM, Hatsukami DK, Hecht S, Stepanov I. Liquid chromatography-electrospray ionization-tandem mass spectrometry quantitation of urinary [pyridine-D4]4-hydroxy-4-(3-pyridyl)butanoic acid, a biomarker of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone metabolic activation in smokers. Chem Res Toxicol 2014; 27:1547-55. [PMID: 25098652 PMCID: PMC4164226 DOI: 10.1021/tx5001915] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Indexed: 01/08/2023]
Abstract
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK, 1) is a potent tobacco-specific lung carcinogen believed to play a key role in the development of lung cancer in smokers. Metabolic activation of NNK to DNA damaging reactive intermediates proceeds via α-hydroxylation pathways. The end products of these pathways are excreted in the urine of smokers as 4-oxo-4-(3-pyridyl)butanoic acid (keto acid, 3) and 4-hydroxy-4-(3-pyridyl)butanoic acid (hydroxy acid, 4). The sum of these biomarkers (after NaBH4 treatment), referred to as total hydroxy acid, could potentially be used to measure the extent of NNK metabolic activation in smokers. However, the same metabolites are formed from nicotine; therefore, there is a need to distinguish the NNK- and nicotine-derived keto and hydroxy acid in smokers' urine. We previously developed a unique methodology based on the use of [pyridine-D4]NNK ([D4]1), which metabolizes to the correspondingly labeled biomarkers. In this study, we developed a sensitive and reproducible assay for the detection and quantitation of total [pyridine-D4]hydroxy acid ([D4]4) in human urine. A two-step derivatization approach was used to convert [D4]4 to [pyridine-D4]methyl 4-hexanoyl-4-(3-pyridyl)butanoate ([D4]6), and an LC-ESI-MS/MS method was developed for the analysis of this derivative with excellent sensitivity, accuracy, and precision. The robustness and reproducibility of the assay was further confirmed by its application for the analysis of urine samples from 87 smokers who smoked [D4]1-containing cigarettes for 1 week. The measured level averaged 130 fmol/mL urine. The developed assay can be used in future studies that may require evaluation of the relative efficiency of NNK metabolic activation in humans.
Collapse
Affiliation(s)
- Meng Jing
- Masonic
Cancer Center, University of Minnesota, 2231 Sixth Street SE, Minneapolis, Minnesota 55455, United States
| | - Yaohua Wang
- Masonic
Cancer Center, University of Minnesota, 2231 Sixth Street SE, Minneapolis, Minnesota 55455, United States
| | - Pramod Upadhyaya
- Masonic
Cancer Center, University of Minnesota, 2231 Sixth Street SE, Minneapolis, Minnesota 55455, United States
| | - Vipin Jain
- Masonic
Cancer Center, University of Minnesota, 2231 Sixth Street SE, Minneapolis, Minnesota 55455, United States
| | - Jian-Min Yuan
- Masonic
Cancer Center, University of Minnesota, 2231 Sixth Street SE, Minneapolis, Minnesota 55455, United States
| | - Dorothy K. Hatsukami
- Masonic
Cancer Center, University of Minnesota, 2231 Sixth Street SE, Minneapolis, Minnesota 55455, United States
| | - Stephen
S. Hecht
- Masonic
Cancer Center, University of Minnesota, 2231 Sixth Street SE, Minneapolis, Minnesota 55455, United States
| | - Irina Stepanov
- Masonic
Cancer Center, University of Minnesota, 2231 Sixth Street SE, Minneapolis, Minnesota 55455, United States
| |
Collapse
|
37
|
Zhai Q, Wang P, Cai Q, Wang Y. Syntheses and characterizations of the in vivo replicative bypass and mutagenic properties of the minor-groove O2-alkylthymidine lesions. Nucleic Acids Res 2014; 42:10529-37. [PMID: 25120272 PMCID: PMC4176383 DOI: 10.1093/nar/gku748] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Endogenous metabolism, environmental exposure, and treatment with some chemotherapeutic agents can all give rise to DNA alkylation, which can occur on the phosphate backbone as well as the ring nitrogen or exocyclic nitrogen and oxygen atoms of nucleobases. Previous studies showed that the minor-groove O2-alkylated thymidine (O2-alkyldT) lesions are poorly repaired and persist in mammalian tissues. In the present study, we synthesized oligodeoxyribonucleotides harboring seven O2-alkyldT lesions, with the alkyl group being a Me, Et, nPr, iPr, nBu, iBu or sBu, at a defined site and examined the impact of these lesions on DNA replication in Escherichia coli cells. Our results demonstrated that the replication bypass efficiencies of the O2-alkyldT lesions decreased with the chain length of the alkyl group, and these lesions directed promiscuous nucleotide misincorporation in E. coli cells. We also found that deficiency in Pol V, but not Pol II or Pol IV, led to a marked drop in bypass efficiencies for most O2-alkyldT lesions. We further showed that both Pol IV and Pol V were essential for the misincorporation of dCMP opposite these minor-groove DNA lesions, whereas only Pol V was indispensable for the T→A transversion introduced by these lesions. Depletion of Pol II, however, did not lead to any detectable alterations in mutation frequencies for any of the O2-alkyldT lesions. Thus, our study provided important new knowledge about the cytotoxic and mutagenic properties of the O2-alkyldT lesions and revealed the roles of the SOS-induced DNA polymerases in bypassing these lesions in E. coli cells.
Collapse
Affiliation(s)
- Qianqian Zhai
- Department of Chemistry, University of California, Riverside, CA 92521, USA
| | - Pengcheng Wang
- Environmental Toxicology Graduate Program, University of California, Riverside, CA 92521, USA
| | - Qian Cai
- Environmental Toxicology Graduate Program, University of California, Riverside, CA 92521, USA
| | - Yinsheng Wang
- Department of Chemistry, University of California, Riverside, CA 92521, USA Environmental Toxicology Graduate Program, University of California, Riverside, CA 92521, USA
| |
Collapse
|
38
|
Zhao L, Balbo S, Wang M, Upadhyaya P, Khariwala SS, Villalta PW, Hecht SS. Quantitation of pyridyloxobutyl-DNA adducts in tissues of rats treated chronically with (R)- or (S)-N'-nitrosonornicotine (NNN) in a carcinogenicity study. Chem Res Toxicol 2013; 26:1526-35. [PMID: 24001146 PMCID: PMC3848204 DOI: 10.1021/tx400235x] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We quantified DNA adducts resulting from 2'-hydroxylation of enantiomers of the tobacco-specific nitrosamine N'-nitrosonornicotine (NNN) in tissues of male F-344 rats after 10, 30, 50, and 70 weeks of treatment with 14 ppm in the drinking water. These rats were in subgroups of a carcinogenicity study in which (S)-NNN was highly tumorigenic in the oral cavity and esophagus, while (R)-NNN was relatively weakly active. DNA adducts were quantified by liquid chromatography-electrospray ionization-tandem mass spectrometry in six tissues: oral mucosa, esophageal mucosa, nasal respiratory mucosa, nasal olfactory mucosa, liver, and lung. O²-[4-(3-Pyridyl)-4-oxobut-1-yl]thymidine (O²-POB-dThd, 7) and 7-[4-(3-pyridyl)-4-oxobut-1-yl]-2'-deoxyguanosine (7-POB-dGuo, 8), the latter as 7-[4-(3-pyridyl)-4-oxobut-1-yl]guanine (7-POB-Gua, 11), were detected at each time point in each tissue. In the target tissues for carcinogenicity, oral mucosa and esophageal mucosa, levels of 7-POB-Gua (11) and O²-POB-dThd (7) were similar, or 11 predominated, while in all other tissues at all time points for both enantiomers, 7 was clearly present in greater amounts than 11. Total measured DNA adduct levels in esophageal mucosa and oral mucosa were higher in rats treated with (S)-NNN than (R)-NNN. The highest adduct levels were found in the nasal respiratory mucosa. DNA adducts generally persisted in all tissues without any sign of substantial decreases throughout the 70 week time course. The results of this study suggest that inefficient repair of 7-POB-dGuo (8) in the rat oral cavity and esophagus may be important in carcinogenesis by NNN and support the development of these DNA adducts as potential biomarkers of NNN metabolic activation in people who use tobacco products.
Collapse
Affiliation(s)
- Lijiao Zhao
- College of Life Science and Bioengineering, Beijing University of Technology , Beijing 100124, China
| | | | | | | | | | | | | |
Collapse
|
39
|
Peterson LA, Urban AM, Vu CC, Cummings ME, Brown LC, Warmka JK, Li L, Wattenberg EV, Patel Y, Stram DO, Pegg AE. Role of aldehydes in the toxic and mutagenic effects of nitrosamines. Chem Res Toxicol 2013; 26:1464-73. [PMID: 24066836 DOI: 10.1021/tx400196j] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
α-Hydroxynitrosamine metabolites of nitrosamines decompose to a reactive diazohydroxide and an aldehyde. To test the hypothesis that the aldehydes contribute to the harmful effects of nitrosamines, the toxic and mutagenic activities of three model methylating agents were compared in Chinese hamster ovary cells expressing or not expressing human O⁶-alkylguanine DNA alkyltransferase (AGT). N-Nitrosomethylurethane (NMUr), acetoxymethylmethylnitrosamine (AMMN), and 4-(methylnitrosamino)-4-acetoxy-1-(3-pyridyl)-1-butanone (NNK-4-OAc) are all activated by ester hydrolysis to methanediazohydroxide. NMUr does not form an aldehyde, whereas AMMN generates formaldehyde, and NNK-4-OAc produces 4-oxo-1-(3-pyridyl)-1-butanone (OPB). Since these compounds were likely to alkylate DNA to different extents, the toxic and mutagenic activities of these compounds were normalized to the levels of the most cytotoxic and mutagenic DNA adduct, O⁶-mG, to assess if the aldehydes contributed to the toxicological properties of these methylating agents. Levels of 7-mG indicated that the differences in cytotoxic and mutagenic effects of these compounds resulted from differences in their ability to methylate DNA. When normalized against the levels of O⁶-mG, there was no difference between these three compounds in cells that lacked AGT. However, AMMN and NNK-4-OAc were more toxic than NMUr in cells expressing AGT when normalized against O⁶-mG levels. In addition, AMMN was more mutagenic than NNK-4-OAc and MNUr in these cells. These findings demonstrate that the aldehyde decomposition products of nitrosamines can contribute to the cytotoxic and/or mutagenic activity of methylating nitrosamines.
Collapse
Affiliation(s)
- Lisa A Peterson
- Division of Environmental Health Sciences and Masonic Cancer Center, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
2'-Deoxythymidine adducts from the anti-HIV drug nevirapine. Molecules 2013; 18:4955-71. [PMID: 23624649 PMCID: PMC6269667 DOI: 10.3390/molecules18054955] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 04/18/2013] [Accepted: 04/19/2013] [Indexed: 12/31/2022] Open
Abstract
Nevirapine (NVP) is a non-nucleoside reverse transcriptase inhibitor (NNRTI) used against HIV-1. Currently, NVP is the most widely used anti-HIV drug in developing countries, both in combination therapy and to prevent mother-to-child transmission of HIV. Despite its efficacy against HIV, NVP produces a variety of toxic responses, including hepatotoxicity and skin rash. It is also associated with increased incidences of hepatoneoplasias in rodents. In addition, epidemiological data suggest that NNRTI use is a risk factor for non-AIDS-defining cancers in HIV-positive patients. Current evidence supports the involvement of metabolic activation to reactive electrophiles in NVP toxicity. NVP metabolism includes oxidation to 12-hydroxy-NVP; subsequent Phase II sulfonation produces an electrophilic metabolite, 12-sulfoxy-NVP, capable of reacting with DNA to yield covalent adducts. Since 2'-deoxythymidine (dT) adducts from several alkylating agents are regarded as having significant mutagenic/carcinogenic potential, we investigated the formation of NVP-dT adducts under biomimetic conditions. Toward this goal, we initially prepared and characterized synthetic NVP-dT adduct standards using a palladium-mediated Buchwald-Hartwig coupling strategy. The synthetic standards enabled the identification, by LC-ESI-MS, of 12-(2'-deoxythymidin-N3-yl)-nevirapine (N3-NVP-dT) in the enzymatic hydrolysate of salmon testis DNA reacted with 12-mesyloxy-NVP, a synthetic surrogate for 12-sulfoxy-NVP. N3-NVP-dT, a potentially cytotoxic and mutagenic DNA lesion, was also the only dT-specific adduct detected upon reaction of dT with 12-mesyloxy-NVP. Our data suggest that N3-NVP-dT may be formed in vivo and play a role in the hepatotoxicity and/or putative hepatocarcinogenicity of NVP.
Collapse
|
41
|
Stepanov I, Muzic J, Le CT, Sebero E, Villalta P, Ma B, Jensen J, Hatsukami D, Hecht SS. Analysis of 4-hydroxy-1-(3-pyridyl)-1-butanone (HPB)-releasing DNA adducts in human exfoliated oral mucosa cells by liquid chromatography-electrospray ionization-tandem mass spectrometry. Chem Res Toxicol 2013; 26:37-45. [PMID: 23252610 PMCID: PMC3631465 DOI: 10.1021/tx300282k] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Quantitation of DNA adducts could provide critical information on the relationship between exposure to tobacco smoke and cancer risk in smokers. In this study, we developed a robust and sensitive liquid chromatography-tandem mass spectrometry method for the analysis of 4-hydroxy-1-(3-pyridyl)-1-butanone (HPB)-releasing DNA adducts in human oral cells, a noninvasive source of DNA for biomarker studies. Isolated DNA undergoes acid hydrolysis, after which samples are purified by solid-phase extraction and analyzed by LC-ESI-MS/MS. The developed method was applied to the analysis of samples obtained via collection with a commercial mouthwash from 30 smokers and 15 nonsmokers. In smokers, the levels of HPB-releasing DNA adducts averaged 12.0 pmol HPB/mg DNA (detected in 20 out of 28 samples with quantifiable DNA yield), and in nonsmokers, the levels of adducts averaged 0.23 pmol/mg DNA (detected in 3 out of 15 samples). For the 30 smoking subjects, matching buccal brushings were also analyzed, and HPB-releasing DNA adducts were detected in 24 out of 27 samples with quantifiable DNA yield, averaging 44.7 pmol HPB/mg DNA. The levels of adducts in buccal brushings correlated with those in mouthwash samples of smokers (R = 0.73, p < 0.0001). Potentially, the method can be applied in studies of individual susceptibility to tobacco-induced cancers in humans.
Collapse
Affiliation(s)
- Irina Stepanov
- Masonic Cancer Center, University of Minnesota, Mayo Mail Code 806, 420 Delaware Street SE, Minneapolis, Minnesota 55455
- Division of Environmental Health Sciences, Mayo Mail Code 806, 420 Delaware Street SE, Minneapolis, Minnesota 55455
| | - John Muzic
- Masonic Cancer Center, University of Minnesota, Mayo Mail Code 806, 420 Delaware Street SE, Minneapolis, Minnesota 55455
| | - Chap T. Le
- Masonic Cancer Center, University of Minnesota, Mayo Mail Code 806, 420 Delaware Street SE, Minneapolis, Minnesota 55455
| | - Erin Sebero
- Masonic Cancer Center, University of Minnesota, Mayo Mail Code 806, 420 Delaware Street SE, Minneapolis, Minnesota 55455
| | - Peter Villalta
- Masonic Cancer Center, University of Minnesota, Mayo Mail Code 806, 420 Delaware Street SE, Minneapolis, Minnesota 55455
| | - Bin Ma
- Masonic Cancer Center, University of Minnesota, Mayo Mail Code 806, 420 Delaware Street SE, Minneapolis, Minnesota 55455
| | - Joni Jensen
- Masonic Cancer Center, University of Minnesota, Mayo Mail Code 806, 420 Delaware Street SE, Minneapolis, Minnesota 55455
| | - Dorothy Hatsukami
- Masonic Cancer Center, University of Minnesota, Mayo Mail Code 806, 420 Delaware Street SE, Minneapolis, Minnesota 55455
| | - Stephen S. Hecht
- Masonic Cancer Center, University of Minnesota, Mayo Mail Code 806, 420 Delaware Street SE, Minneapolis, Minnesota 55455
| |
Collapse
|
42
|
Urban AM, Upadhyaya P, Cao Q, Peterson LA. Formation and repair of pyridyloxobutyl DNA adducts and their relationship to tumor yield in A/J mice. Chem Res Toxicol 2012; 25:2167-78. [PMID: 22928598 DOI: 10.1021/tx300245w] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is a known human carcinogen. It generates methyl and pyridyloxobutyl DNA adducts. The role of the methyl DNA adducts has been well-established in the tumorigenic properties of NNK. However, the role of the pyridyloxobutyl DNA adducts is unclear. Four pyridyloxobutyl DNA adducts have been characterized: 7-[4-3-(pyridyl)-4-oxobut-1-yl]guanine (7-pobG), O²-[4-3-(pyridyl)-4-oxobut-1-yl]-cytodine (O²-pobC), O²-[4-3-(pyridyl)-4-oxobut-1yl]thymidine (O²-pobdT), and O⁶-[4-3-(pyridyl)-4-oxobut-1-yl]-2'-deoxyguanosine (O⁶-pobdG). Mutagenic O⁶-pobdG is thought to contribute to the tumorigenic properties of the pyridyloxobutylation pathway. It is repaired by O⁶-alkylguanine-DNA alkyltransferase (AGT). To explore the role of O⁶-pobdG formation and repair in the tumorigenic properties of NNK, A/J mice were given single or multiple doses of the model pyridyloxobutylating agent 4-(acetoxymethyl-nitrosamino)-1-(3-pyridyl)-1-butanone (NNKOAc) in the presence or absence of the AGT depletor, O⁶-benzylguanine. Levels of the four pyridyloxobutyl DNA adducts were measured in the lung at 8, 48, or 96 h following treatment and compared to the lung tumorigenic activity of these treatments. AGT depletion had only a modest effect on the levels of O⁶-pobdG and did not increase tumor formation. Three pyridyloxobutyl DNA adducts, 7-pobG, O²-pobdT, and O⁶-pobdG, persisted in lung DNA at significant levels for up to 96 h post-treatment, suggesting that all three adducts may contribute to the tumorigenic properties of NNK.
Collapse
Affiliation(s)
- Anna M Urban
- Division of Environmental Health Sciences and ‡Masonic Cancer Center, University of Minnesota , Minneapolis, Minnesota 55455, USA
| | | | | | | |
Collapse
|
43
|
Tretyakova N, Goggin M, Sangaraju D, Janis G. Quantitation of DNA adducts by stable isotope dilution mass spectrometry. Chem Res Toxicol 2012; 25:2007-35. [PMID: 22827593 DOI: 10.1021/tx3002548] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Exposure to endogenous and exogenous chemicals can lead to the formation of structurally modified DNA bases (DNA adducts). If not repaired, these nucleobase lesions can cause polymerase errors during DNA replication, leading to heritable mutations and potentially contributing to the development of cancer. Because of their critical role in cancer initiation, DNA adducts represent mechanism-based biomarkers of carcinogen exposure, and their quantitation is particularly useful for cancer risk assessment. DNA adducts are also valuable in mechanistic studies linking tumorigenic effects of environmental and industrial carcinogens to specific electrophilic species generated from their metabolism. While multiple experimental methodologies have been developed for DNA adduct analysis in biological samples, including immunoassay, HPLC, and ³²P-postlabeling, isotope dilution high performance liquid chromatography-electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS) generally has superior selectivity, sensitivity, accuracy, and reproducibility. As typical DNA adduct concentrations in biological samples are between 0.01-10 adducts per 10⁸ normal nucleotides, ultrasensitive HPLC-ESI-MS/MS methodologies are required for their analysis. Recent developments in analytical separations and biological mass spectrometry, especially nanoflow HPLC, nanospray ionization MS, chip-MS, and high resolution MS, have pushed the limits of analytical HPLC-ESI-MS/MS methodologies for DNA adducts, allowing researchers to accurately measure their concentrations in biological samples from patients treated with DNA alkylating drugs and in populations exposed to carcinogens from urban air, drinking water, cooked food, alcohol, and cigarette smoke.
Collapse
Affiliation(s)
- Natalia Tretyakova
- Department of Medicinal Chemistry and Masonic Cancer Center, University of Minnesota , Minneapolis, Minnesota 55455, USA.
| | | | | | | |
Collapse
|
44
|
Gowda ASP, Krishnegowda G, Suo Z, Amin S, Spratt TE. Low fidelity bypass of O(2)-(3-pyridyl)-4-oxobutylthymine, the most persistent bulky adduct produced by the tobacco specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone by model DNA polymerases. Chem Res Toxicol 2012; 25:1195-202. [PMID: 22533615 DOI: 10.1021/tx200483g] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is one of the most important human carcinogens. It is metabolized to produce a variety of methyl and 4-(3-pyridyl)-4-oxo-butyl (POB) DNA adducts. A potentially important POB adduct is O(2)-[4-(3-pyridyl)-4-oxobut-1-yl]thymidine (O(2)-POB-dT) because it is the most abundant POB adduct in NNK-treated rodents. To evaluate the mutagenic properties of O(2)-POB-dT, we measured the rate of insertion of dNTPs opposite and extension past both O(2)-POB-dT and O(2)-methylthymidine (O(2)-Me-dT) by two model polymerases, E. coli DNA polymerase I (Klenow fragment) with the proofreading exonuclease activity inactivated (Kf) and Sulfolobus solfataricus DNA polymerase IV (Dpo4). We found that the size of the alkyl chain only marginally affected the reactivity and that the specificity of adduct bypass was very low. The k(cat)/K(m) for the Kf catalyzed incorporation opposite and extension past the adducts was reduced ∼10(6)-fold when compared to undamaged DNA. Dpo4 catalyzed the incorporation opposite and extension past the adducts approximately 10(3)-fold more slowly than undamaged DNA. The dNTP specificity was less for Dpo4 than for Kf. In general, dA was the preferred base pair partner for O(2)-Me-dT and dT the preferred base pair partner for O(2)-POB-dT. With enzyme in excess over DNA, the time courses of the reactions showed a biphasic kinetics that indicates the formation inactive binary and ternary complexes.
Collapse
Affiliation(s)
- A S Prakasha Gowda
- Department of Biochemistry and Molecular Biology, Penn State Hershey Cancer Institute, Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033, USA
| | | | | | | | | |
Collapse
|
45
|
Zhou HY, Hu GX, Lian QQ, Morris D, Ge RS. The metabolism of steroids, toxins and drugs by 11β-hydroxysteroid dehydrogenase 1. Toxicology 2012; 292:1-12. [DOI: 10.1016/j.tox.2011.11.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Revised: 11/17/2011] [Accepted: 11/21/2011] [Indexed: 11/25/2022]
|
46
|
Jasti VP, Spratt TE, Basu AK. Tobacco-specific nitrosamine-derived O2-alkylthymidines are potent mutagenic lesions in SOS-induced Escherichia coli. Chem Res Toxicol 2011; 24:1833-5. [PMID: 22029400 PMCID: PMC3221470 DOI: 10.1021/tx200435d] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Indexed: 12/02/2022]
Abstract
To investigate the biological effects of the O(2)-alkylthymidines induced by the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), we have replicated a plasmid containing O(2)-methylthymidine (O(2)-Me-dT) or O(2)-[4-(3-pyridyl-4-oxobut-1-yl]thymidine (O(2)-POB-dT) in Escherichia coli with specific DNA polymerase knockouts. High genotoxicity of the adducts was manifested in the low yield of transformants from the constructs, which was 2-5% in most strains but increased 2-4-fold with SOS. In the SOS-induced wild type E. coli, O(2)-Me-dT and O(2)-POB-dT induced 21% and 56% mutations, respectively. For O(2)-POB-dT, the major type of mutation was T → G followed by T → A, whereas for O(2)-Me-dT, T → G and T → A occurred in equal frequency. For both lesions, T → C also was detected in low frequency. The T → G mutation was reduced in strains with deficiency in any of the three SOS polymerases. By contrast, T → A was abolished in the pol V(-) strain, while its frequency in other strains remained unaltered. This suggests that pol V was responsible for the T → A mutations. The potent mutagenicity of these lesions may be related to NNK mutagenesis and carcinogenesis.
Collapse
Affiliation(s)
- Vijay P. Jasti
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Thomas E. Spratt
- Department of Biochemistry and Molecular Biology, Penn State College of Medicine, Hershey, Pennsylvania 17033, United States
| | - Ashis K. Basu
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| |
Collapse
|
47
|
Lochan R, Reeves HL, Daly AK, Charnley RM. The role of tobacco-derived carcinogens in pancreas cancer. ISRN ONCOLOGY 2011; 2011:249235. [PMID: 22084727 PMCID: PMC3196993 DOI: 10.5402/2011/249235] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Accepted: 05/14/2011] [Indexed: 01/17/2023]
Abstract
The extremely poor outcome from pancreas cancer is well known. However, its aetiology less well appreciated, and the molecular mechanisms underlying this are poorly understood. Tobacco usage is one of the strongest risk factors for this disease, and this is a completely avoidable hazard. In addition, there are well described hereditary diseases which predispose, and familial pancreas cancer. We have sought here to summarise the role of tobacco-derived carcinogens and the mode of their tumorigenic action on the pancreas. There is compelling evidence from animal and human studies (laboratory including cell line studies and epidemiologic) that tobacco derived carcinogens cause pancreas cancer. However, the manner in which they do so is not entirely apparent. There is also compelling evidence that synergism with genetic and other life-style factors-like diet obesity-results in a multifactorial causation of the disease. Ascertaining the role of tobacco carcinogens in the development of this cancer and their interaction with other risk factors will enable novel therapeutic and preventative strategies to improve outcome from this appalling malignancy.
Collapse
Affiliation(s)
- Rajiv Lochan
- Hepato-Pancreato-Biliary Unit, Department of Surgery, Freeman Hospital, Newcastle upon Tyne NE7 7DN, UK
| | | | | | | |
Collapse
|
48
|
Krishnegowda G, Sharma AK, Krzeminski J, Gowda AP, Lin JM, Desai D, Spratt TE, Amin S. Facile syntheses of O(2)-[4-(3-pyridyl-4-oxobut-1-yl]thymidine, the major adduct formed by tobacco specific nitrosamine 4-methylnitrosamino-1-(3-pyridyl)-1-butanone (NNK) in vivo, and its site-specifically adducted oligodeoxynucleotides. Chem Res Toxicol 2011; 24:960-7. [PMID: 21524094 PMCID: PMC3118900 DOI: 10.1021/tx200127j] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
O(2)-[4-(3-Pyridyl)-4-oxobut-1-yl]thymidine (O(2)-POB-dThd) is the most persistent adduct detected in the lung and liver of rats treated with tobacco specific nitrosamines: N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), and its metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL). It is an important biomarker to assess the human exposure to these carcinogens. The only synthetic method reported for O(2)-POB-dThd requires repeated HPLC purifications and could only be used to prepare an analytical standard due to very low yield (0.4%). We have developed for the first time a regioselective and efficient method for the total synthesis of O(2)-POB-dThd and its site-specifically adducted oligonucleotides. The main step in the synthesis of O(2)-POB-dThd was achieved by a novel method. The treatment of O(2)-5'-anhydrothymidine with the sodium salt of 4-(1,3-dithian-2-yl)-4-(3-pyridyl)butan-1-ol gave exclusively the O(2)-alkylated adduct, which was deprotected in one step to furnish the desired O(2)-POB-dThd in excellent yield. The product was characterized by NMR ((1)H and (13)C), high-resolution MS, and HPLC analysis. This work provided for the first time a reliable method for large scale total synthesis of O(2)-POB-dThd that allowed for solid state site-specifically adducted oligomer synthesis. The O(2)-POB-dThd was converted to its phosphoramidite and subsequently used for the synthesis of oligodeoxynucleotides by standard methods. The oligomers were characterized by MS and HPLC analysis. These oligomers will facilitate the elucidation of the mutagenic potential of the O(2)-POB-dThd adduct, which will provide further insight into the role of tobacco-specific nitrosamines in inducing cancers in smokers.
Collapse
Affiliation(s)
- Gowdahalli Krishnegowda
- Department of Pharmacology, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033
| | - Arun K. Sharma
- Department of Pharmacology, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033
| | - Jacek Krzeminski
- Department of Pharmacology, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033
| | - A.S. Prakasha Gowda
- Department of Biochemistry and Molecular Biology, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033
| | - Jyh-Ming Lin
- Department of Pharmacology, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033
| | - Dhimant Desai
- Department of Pharmacology, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033
| | - Thomas E. Spratt
- Department of Biochemistry and Molecular Biology, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033
| | - Shantu Amin
- Department of Pharmacology, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033
| |
Collapse
|
49
|
Böhm F, Schmid D, Denzinger S, Wieland WF, Richter E. DNA adducts of ortho-toluidine in human bladder. Biomarkers 2010; 16:120-8. [PMID: 21117897 DOI: 10.3109/1354750x.2010.534556] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND 4-Aminobiphenyl (4-ABP) and o-toluidine are known human bladder carcinogens, but only 4-ABP-releasing DNA adducts are known. METHODS Determination of 4-ABP and o-toluidine-releasing DNA adducts in epithelial and submucosal bladder tissues of sudden death victims (SDV: n=46), and bladder tumours (n=12) by gas chromatography/mass spectrometry. RESULTS Above background, 4 and 11 of 12 tumour samples contained adducts of 4-ABP (0.057 ± 0.125 fmol/µg DNA) and o-toluidine (8.72 ± 4.49 fmol/µg DNA), respectively. Lower adduct levels were present in both epithelial and submucosal bladder tissues of SDV (4-ABP: 0.011 ± 0.022 and 0.019 ± 0.047 fmol/µg DNA; o-toluidine: 0.24 ± 0.63 and 0.27 ± 0.70 fmol/µg DNA). CONCLUSION Detection of o-toluidine-releasing DNA adducts support the carcinogenicity of o-toluidine in the human bladder.
Collapse
Affiliation(s)
- Francine Böhm
- Walther Straub Institute, Department of Toxicology, Ludwig-Maximilians-University, Nussbaumstrasse 26, D-80336 Munich, Germany
| | | | | | | | | |
Collapse
|
50
|
Peterson LA. Formation, repair, and genotoxic properties of bulky DNA adducts formed from tobacco-specific nitrosamines. J Nucleic Acids 2010; 2010. [PMID: 20871819 PMCID: PMC2943119 DOI: 10.4061/2010/284935] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2010] [Accepted: 07/08/2010] [Indexed: 12/24/2022] Open
Abstract
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N′-nitrosonornicotine (NNN) are tobacco-specific nitrosamines present in tobacco products and smoke. Both compounds are carcinogenic in laboratory animals, generating tumors at sites comparable to those observed in smokers. These Group 1 human carcinogens are metabolized to reactive intermediates that alkylate DNA. This paper focuses on the DNA pyridyloxobutylation pathway which is common to both compounds. This DNA route generates 7-[4-(3-pyridyl)-4-oxobut-1-yl]-2′-deoxyguanosine, O2-[4-(3-pyridyl)-4-oxobut-1-yl]-2′-deoxycytosine, O2-[4-(3-pyridyl)-4-oxobut-1-yl]-2′-deoxythymidine, and O6-[4-(3-pyridyl)-4-oxobut-1-yl]-2′-deoxyguanosine as well as unstable adducts which dealkylate to release 4-hydroxy-1-{3-pyridyl)-1-butanone or depyriminidate/depurinate to generate abasic sites. There are multiple repair pathways responsible for protecting against the genotoxic effects of these adducts, including adduct reversal as well as base and nucleotide excision repair pathways. Data indicate that several DNA adducts contribute to the overall mutagenic properties of pyridyloxobutylating agents. Which adducts contribute to the carcinogenic properties of this pathway are likely to depend on the biochemistry of the target tissue.
Collapse
Affiliation(s)
- Lisa A Peterson
- Division of Environmental Health Sciences, Masonic Cancer Center, Mayo Mail Code 806, 420 Delaware St SE, Minneapolis, MN 55455, USA
| |
Collapse
|