1
|
Narayan V, Pandey AK, Dwivedi A, Mwankemwa BS, Maurya A, Sharma AK, Singh V. Comprehensive quantum chemical calculations and molecular docking analysis of uracil mustard by first principle. J INDIAN CHEM SOC 2022. [DOI: 10.1016/j.jics.2022.100580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
2
|
Chen H, Cui Z, Hejazi L, Yao L, Walmsley SJ, Rizzo CJ, Turesky RJ. Kinetics of DNA Adducts and Abasic Site Formation in Tissues of Mice Treated with a Nitrogen Mustard. Chem Res Toxicol 2020; 33:988-998. [PMID: 32174110 DOI: 10.1021/acs.chemrestox.0c00012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Nitrogen mustards (NM) are an important class of chemotherapeutic drugs used in the treatment of malignant tumors. The accepted mechanism of action of NM is through the alkylation of DNA bases. NM-adducts block DNA replication in cancer cells by forming cytotoxic DNA interstrand cross-links. We previously characterized several adducts formed by reaction of bis(2-chloroethyl)ethylamine (NM) with calf thymus (CT) DNA and the MDA-MB-231 mammary tumor cell line. The monoalkylated N7-guanine (NM-G) adduct and its cross-link (G-NM-G) were major lesions. The cationic NM-G undergoes a secondary reaction through depurination to form an apurinic (AP) site or reacts with hydroxide to yield the stable ring-opened N5-substituted formamidopyrimidine (NM-Fapy-G) adduct. Both of these lesions are mutagenic and may contribute to secondary tumor development, a major clinical limitation of NM chemotherapy. We established a kinetic model with NM-treated female mice and measured the rates of formation and removal of NM-DNA adducts and AP sites. We employed liquid chromatography-mass spectrometry (LC-MS) to measure NM-G, G-NM-G, and NM-Fapy-G adducts in liver, lung, and spleen over 168 h. NM-G reached a maximum level within 6 h in all organs and then rapidly declined. The G-NM-G cross-link and NM-FapyG were more persistent with half-lives over three-times longer than NM-G. We quantified AP site lesions in the liver and showed that NM treatment increased AP site levels by 3.7-fold over the basal levels at 6 h. The kinetics of AP site repair closely followed the rate of removal of NM-G; however, AP sites remained 1.3-fold above basal levels 168 h post-treatment with NM. Our data provide new insights into NM-induced DNA damage and biological processing in vivo. The quantitative measurement of the spectrum of NM adducts and AP sites can serve as biomarkers in the design and assessment of the efficacy of novel chemotherapeutic regimens.
Collapse
Affiliation(s)
| | | | | | | | | | - Carmelo J Rizzo
- Departments of Chemistry and Biochemistry, and Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, Tennessee 37067, United States
| | | |
Collapse
|
3
|
Diethelm-Varela B, Ai Y, Liang D, Xue F. Nitrogen Mustards as Anticancer Chemotherapies: Historic Perspective, Current Developments and Future Trends. Curr Top Med Chem 2019; 19:691-712. [PMID: 30931858 DOI: 10.2174/1568026619666190401100519] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 02/11/2019] [Accepted: 02/25/2019] [Indexed: 12/30/2022]
Abstract
Nitrogen mustards, a family of DNA alkylating agents, marked the start of cancer pharmacotherapy. While traditionally characterized by their dose-limiting toxic effects, nitrogen mustards have been the subject of intense research efforts, which have led to safer and more effective agents. Even though the alkylating prodrug mustards were first developed decades ago, active research on ways to improve their selectivity and cytotoxic efficacy is a currently active topic of research. This review addresses the historical development of the nitrogen mustards, outlining their mechanism of action, and discussing the improvements on their therapeutic profile made through rational structure modifications. A special emphasis is made on discussing the nitrogen mustard prodrug category, with Cyclophosphamide (CPA) serving as the main highlight. Selected insights on the latest developments on nitrogen mustards are then provided, limiting such information to agents that preserve the original nitrogen mustard mechanism as their primary mode of action. Additionally, future trends that might follow in the quest to optimize these invaluable chemotherapeutic medications are succinctly suggested.
Collapse
Affiliation(s)
- Benjamin Diethelm-Varela
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland 21201, United States
| | - Yong Ai
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland 21201, United States
| | - Dongdong Liang
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland 21201, United States
| | - Fengtian Xue
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland 21201, United States
| |
Collapse
|
4
|
Nejad MI, Johnson KM, Price NE, Gates KS. A New Cross-Link for an Old Cross-Linking Drug: The Nitrogen Mustard Anticancer Agent Mechlorethamine Generates Cross-Links Derived from Abasic Sites in Addition to the Expected Drug-Bridged Cross-Links. Biochemistry 2016; 55:7033-7041. [PMID: 27992994 DOI: 10.1021/acs.biochem.6b01080] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Nitrogen mustard anticancer drugs generate highly reactive aziridinium ions that alkylate DNA. Monoadducts arising from reaction with position N7 of guanine residues are the major DNA adducts generated by these agents. Interstrand cross-links in which the drug bridges position N7 of two guanine residues are formed in low yields relative to those of the monoadducts but are generally thought to be central to medicinal activity. The N7-alkylguanine residues generated by nitrogen mustards are depurinated to yield abasic (Ap) sites in duplex DNA. Here, we show that Ap sites generated by the nitrogen mustard mechlorethamine lead to interstrand cross-links of a type not previously associated with this drug. Gel electrophoretic data were consistent with early evolution of the expected drug-bridged cross-links, followed by the appearance of Ap-derived cross-links. The evidence is further consistent with a reaction pathway involving alkylation of a guanine residue in a 5'-GT sequence, followed by depurination to generate the Ap site, and cross-link formation via reaction of the Ap aldehyde residue with the opposing adenine residue at this site [Price, N. E., Johnson, K. M., Wang, J., Fekry, M. I., Wang, Y., and Gates, K. S. (2014) J. Am. Chem. Soc. 136, 3483-3490]. The monofunctional DNA-alkylating agents 2-chloro-N,N-diethylethanamine 5, (2-chloroethyl)ethylsulfide 6, and natural product leinamycin similarly were found to induce the formation of Ap-derived cross-links in duplex DNA. This work provides the first characterization of Ap-derived cross-links at sequences in which a cytosine residue is located directly opposing the Ap site. Cross-linking processes of this type could be relevant in medicine and biology because Ap sites with directly opposing cytosine residues occur frequently in genomic DNA via spontaneous or enzymatic depurination of guanine and N7-alkylguanine residues.
Collapse
Affiliation(s)
- Maryam Imani Nejad
- Department of Chemistry, University of Missouri , 125 Chemistry Building, Columbia, Missouri 65211, United States
| | - Kevin M Johnson
- Department of Chemistry, University of Missouri , 125 Chemistry Building, Columbia, Missouri 65211, United States
| | - Nathan E Price
- Department of Chemistry, University of Missouri , 125 Chemistry Building, Columbia, Missouri 65211, United States
| | - Kent S Gates
- Department of Chemistry, University of Missouri , 125 Chemistry Building, Columbia, Missouri 65211, United States.,Department of Biochemistry, University of Missouri , 125 Chemistry Building, Columbia, Missouri 65211, United States
| |
Collapse
|
5
|
De Alencar TAM, Wilmart-Gonçalves TC, Vidal LS, Fortunato RS, Leitão AC, Lage C. Bipyridine (2,2'-dipyridyl) potentiates Escherichia coli lethality induced by nitrogen mustard mechlorethamine. Mutat Res 2014; 765:40-7. [PMID: 24632511 DOI: 10.1016/j.mrfmmm.2014.02.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 02/19/2014] [Accepted: 02/28/2014] [Indexed: 12/21/2022]
Abstract
Alkylating agents are used in anti-tumor chemotherapy because they bind covalently to DNA and generate adducts that may lead to cell death. Bifunctional (HN2) and monofunctional (HN1) nitrogen are two such agents, and HN2 was the first drug successfully employed in anti-leukemia chemotherapy. Currently, HN2 is used either alone or combined with other drugs to treat Hodgkin's disease. It is well known that several crosslinking agents require metabolic activation via reactive oxygen species (ROS) to exert their lethal effects. The objective of this work was therefore to determine whether the abovementioned mustards would also require metabolic activation to exert lethal action against Escherichia coli. For this purpose, we measured survival following exposure to HN2 in E. coli strains that were deficient in nucleotide excision repair (uvrA NER mutant), base excision repair (xthA nfo nth fpg BER mutant) or superoxide dismutase (sodAB mutant) activity. We also performed the same experiments in cells pretreated with an iron chelator (2,2'-dipyridyl, DIP). The NER and BER mutants were only sensitive to HN2 treatment (survival rates similar to those of the wild-type were achieved with 5-fold lower HN2 doses). However, wild-type and sodAB strains were not sensitive to treatment with HN2. In all tested strains, survival dropped by 2.5-fold following pretreatment with DIP compared to treatment with HN2 alone. Furthermore, DIP treatment increased ROS generation in both wild type and sodAB-deficient strains. Based on these data and on the survival of the SOD-deficient strain, we suggest that the increased production of ROS caused by Fe(2+) chelation may potentiate the lethal effects of HN2 but not HN1. This potentiation may arise as a consequence of enhancement in the number of or modification of the type of lesions formed. No sensitization was observed for the non-crosslinkable HN2 analog, HN1.
Collapse
Affiliation(s)
| | | | - L S Vidal
- Laboratório de Radiobiologia Molecular, Brazil
| | | | - A C Leitão
- Laboratório de Radiobiologia Molecular, Brazil
| | - C Lage
- Laboratório de Radiações em Biologia, Brazil.
| |
Collapse
|
6
|
Niakani A, Farrokhi F, Hasanzadeh S. Decapeptyl ameliorates cyclophosphamide-induced reproductive toxicity in male Balb/C mice: histomorphometric, stereologic and hormonal evidences. IRANIAN JOURNAL OF REPRODUCTIVE MEDICINE 2013; 11:791-800. [PMID: 24639699 PMCID: PMC3941336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 03/03/2012] [Accepted: 06/08/2013] [Indexed: 11/16/2022]
Abstract
BACKGROUND Gonadotropin-releasing hormone (GnRH) is a reproductive key hormone. The GnRH analogues are widely used in in vitro fertilization and treatment of sex hormone-depended cancers induced by the materials used in chemotherapeutic agents. OBJECTIVE The aim of this study is to evaluate the effects of cyclophosphamide and decapeptyl (analogues of GnRH) on histomorphometry and stereology of testicular tissue as well as gonadotropic and gonadal hormones indices in mice. MATERIALS AND METHODS For this study, 24 adult male Balb/C strain mice were divided in four groups; first, cyclophosphamide (65 mg/kg/body weight (BW)), second, decapeptyl (0.05 mg/kg/BW), third, decapeptyl at first, and after 10 days of cyclophosphamide injection, and control group was received same volume of sterile saline. In order to evaluate the tissue changes in testes of the mice, sections were prepared and stained with Hematoxylin-Eosine, Periodic Acid Schief's (PAS) and Oil-Red-O staining techniques. RESULTS The cyclophosphamide causes histomorphologic changes in the testicular tissue; whereas such changes by decapeptyl were comparatively mild. The morphometric results revealed significant reduction in diameters of seminiferous tubules (p=0.02), and the stereological results confirmed significant differences in spermatogenesis (SI) as well as rate of tubal differentiation (TDI) indices between experimental and control groups (p=0.001). In addition, the morphometric findings proved that, there are significant decrease (p=0.001) in thicknesses of epithelia and stereologic result revealed reduction in number of cell layers in both decapeptyl and chemotherapy groups, but the decrements of these parameters were significant (p=0.02) in later group. In groups that had received cyclophosphamide, and decapeptyl alone, the LH and testosterone levels were decreased significantly (p=0.03), whereas in those that had received decapeptyl along with cyclophosphamide, the LH and FSH levels showed a decline but the level of testosterone increased. CONCLUSION These results demonstrated that, analogue of GnRH i.e., decapeptyl protect morphologic, morphometric, and stereologic alterations of the testes tissue, as well as gonadotropic and gonadal hormonal changes preceding cyclophosphamide treatment in male mice. This article extracted from M.Sc. thesis. (Afsaneh Niakani).
Collapse
Affiliation(s)
- Afsaneh Niakani
- Department of Biology, Faculty of Science, Urmia University, Urmia, Iran.
| | - Farah Farrokhi
- Department of Biology, Faculty of Science, Urmia University, Urmia, Iran.
| | - Shapour Hasanzadeh
- Department of Basic Veterinary Science, Fculty of Veterinary Medicine, Urmia University, Urmia, Iran.
| |
Collapse
|
7
|
|
8
|
Johnson KM, Price NE, Wang J, Fekry MI, Dutta S, Seiner DR, Wang Y, Gates KS. On the formation and properties of interstrand DNA-DNA cross-links forged by reaction of an abasic site with the opposing guanine residue of 5'-CAp sequences in duplex DNA. J Am Chem Soc 2013; 135:1015-25. [PMID: 23215239 DOI: 10.1021/ja308119q] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We recently reported that the aldehyde residue of an abasic (Ap) site in duplex DNA can generate an interstrand cross-link via reaction with a guanine residue on the opposing strand. This finding is intriguing because the highly deleterious nature of interstrand cross-links suggests that even small amounts of Ap-derived cross-links could make a significant contribution to the biological consequences stemming from the generation of Ap sites in cellular DNA. Incubation of 21-bp duplexes containing a central 5'-CAp sequence under conditions of reductive amination (NaCNBH(3), pH 5.2) generated much higher yields of cross-linked DNA than reported previously. At pH 7, in the absence of reducing agents, these Ap-containing duplexes also produced cross-linked duplexes that were readily detected on denaturing polyacrylamide gels. Cross-link formation was not highly sensitive to reaction conditions, and the cross-link, once formed, was stable to a variety of workup conditions. Results of multiple experiments including MALDI-TOF mass spectrometry, gel mobility, methoxyamine capping of the Ap aldehyde, inosine-for-guanine replacement, hydroxyl radical footprinting, and LC-MS/MS were consistent with a cross-linking mechanism involving reversible reaction of the Ap aldehyde residue with the N(2)-amino group of the opposing guanine residue in 5'-CAp sequences to generate hemiaminal, imine, or cyclic hemiaminal cross-links (7-10) that were irreversibly converted under conditions of reductive amination (NaCNBH(3)/pH 5.2) to a stable amine linkage. Further support for the importance of the exocyclic N(2)-amino group in this reaction was provided by an experiment showing that installation of a 2-aminopurine-thymine base pair at the cross-linking site produced high yields (15-30%) of a cross-linked duplex at neutral pH, in the absence of NaCNBH(3).
Collapse
Affiliation(s)
- Kevin M Johnson
- Department of Chemistry, University of Missouri, 125 Chemistry Building, Columbia, Missouri 65211, USA
| | | | | | | | | | | | | | | |
Collapse
|
9
|
Polavarapu A, Stillabower JA, Stubblefield SGW, Taylor WM, Baik MH. The mechanism of guanine alkylation by nitrogen mustards: a computational study. J Org Chem 2012; 77:5914-21. [PMID: 22681226 DOI: 10.1021/jo300351g] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The thermodynamics and kinetics for the monofunctional binding of nitrogen mustard class of anticancer drugs to purine bases of DNA were studied computationally using guanine and adenine as model substrates. Mechlorethamine and melphalan are used as model systems in order to better understand the difference in antitumor activity of aliphatic and aromatic mustards, respectively. In good agreement with experiments that suggested the accumulation of a reactive intermediate in the case of mechlorethamine, our model predicts a significant preference for the formation of corresponding aziridinium ion for mechlorethamine, while the formation of the aziridinium ion is not computed to be preferred when melphalan is used. Two effects are found that contribute to this difference. First, the ground state of the drug shows a highly delocalized lone pair on the amine nitrogen of the melphalan, which makes the subsequent cyclization more difficult. Second, because of the aromatic substituent connected to the amine nitrogen of melphalan, a large energy penalty has to be paid for solvation. A detailed study of energy profiles for the two-step mechanism for alkylation of guanine and adenine was performed. Alkylation of guanine is ∼6 kcal mol(-1) preferred over adenine, and the factors contributing to this preference were explained in our previous study of cisplatin binding to purine bases. A detailed analysis of energy profiles of mechlorethamine and melphalan binding to guanine and adenine are presented to provide an insight into rate limiting step and the difference in reactivity and stability of the intermediate in both nitrogen mustards, respectively.
Collapse
Affiliation(s)
- Abhigna Polavarapu
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave., Bloomington, Indiana 47405, USA
| | | | | | | | | |
Collapse
|
10
|
Abdallah QM, Phillips RM, Johansson F, Helleday T, Cosentino L, Abdel-Rahman H, Etzad J, Wheelhouse RT, Kiakos K, Bingham JP, Hartley JA, Patterson LH, Pors K. Minor structural modifications to alchemix influence mechanism of action and pharmacological activity. Biochem Pharmacol 2012; 83:1514-22. [DOI: 10.1016/j.bcp.2012.02.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Accepted: 02/21/2012] [Indexed: 10/28/2022]
|
11
|
|
12
|
Fekry MI, Price NE, Zang H, Huang C, Harmata M, Brown P, Daniels JS, Gates KS. Thiol-activated DNA damage by α-bromo-2-cyclopentenone. Chem Res Toxicol 2011; 24:217-28. [PMID: 21250671 DOI: 10.1021/tx100282b] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Some biologically active chemicals are relatively stable in the extracellular environment but, upon entering the cell, undergo biotransformation into reactive intermediates that covalently modify DNA. The diverse chemical reactions involved in the bioactivation of DNA-damaging agents are both fundamentally interesting and of practical importance in medicinal chemistry and toxicology. The work described here examines the bioactivation of α-haloacrolyl-containing molecules. The α-haloacrolyl moiety is found in a variety of cytotoxic natural products including clionastatin B, bromovulone III, discorahabdins A, B, and C, and trichodenone C, in mutagens such as 2-bromoacrolein and 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), and in the anticancer drug candidates brostallicin and PNU-151807. Using α-bromo-2-cyclopentenone (1) as a model compound, the activation of α-haloacrolyl-containing molecules by biological thiols was explored. The results indicate that both low molecular weight and peptide thiols readily undergo conjugate addition to 1. The resulting products are consistent with a mechanism in which initial addition of thiols to 1 is followed by intramolecular displacement of bromide to yield a DNA-alkylating episulfonium ion intermediate. The reaction of thiol-activated 1 with DNA produces labile lesions at deoxyguanosine residues. The sequence specificity and salt dependence of this process is consistent with involvement of an episulfonium ion intermediate. The alkylated guanine residue resulting from the thiol-triggered reaction of 1 with duplex DNA was characterized using mass spectrometry. The results provide new insight regarding the mechanisms by which thiols can bioactivate small molecules and offer a more complete understanding of the molecular mechanisms underlying the biological activity of cytotoxic, mutagenic, and medicinal compounds containing the α-haloacrolyl group.
Collapse
Affiliation(s)
- Mostafa I Fekry
- Department of Chemistry, University of Missouri, 125 Chemistry Building Columbia, Missouri 65211, United States
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Mann DJ. Aziridinium Ion Ring Formation from Nitrogen Mustards: Mechanistic Insights from Ab Initio Dynamics. J Phys Chem A 2010; 114:4486-93. [DOI: 10.1021/jp9079553] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
14
|
Lage C, Alencar TD, Vidal LS, Wilmart-Gonçalves TC, Borba-Santos L, Alves AM, Paula-Pereira-Jr MV, Felicio DL, Irineu R, Cardoso JS, Leitão AC. Targeting DNA in therapies: using damages to design strategies on cell sensitisation. ACTA ACUST UNITED AC 2008. [DOI: 10.1088/1742-6596/101/1/012013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
15
|
Reactions of DNA bases with the anti-cancer nitrogen mustard mechlorethamine: A quantum chemical study. Chem Phys Lett 2007. [DOI: 10.1016/j.cplett.2007.10.072] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
16
|
Antsypovitch SI, Oretskaya TS. Double-helical nucleic acids with cross-linked strands: synthesis and applications in molecular biology. RUSSIAN CHEMICAL REVIEWS 2007. [DOI: 10.1070/rc1998v067n03abeh000345] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
17
|
David-Cordonnier MH, Casely-Hayford M, Kouach M, Briand G, Patterson LH, Bailly C, Searcey M. Stereoselectivity, Sequence Specificity and Mechanism of Action of the Azinomycin Epoxide. Chembiochem 2006; 7:1658-61. [PMID: 16991169 DOI: 10.1002/cbic.200600244] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
18
|
De Alencar TAM, Leitão AC, Lage C. Nitrogen mustard- and half-mustard-induced damage in Escherichia coli requires different DNA repair pathways. Mutat Res 2005; 582:105-15. [PMID: 15781216 DOI: 10.1016/j.mrgentox.2005.01.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2004] [Revised: 01/10/2005] [Accepted: 01/14/2005] [Indexed: 11/25/2022]
Abstract
Bifunctional alkylating agents are used in tumor chemotherapy to induce the death of malignant cells through blockage of DNA replication. Nitrogen mustards are commonly used chemotherapeutic agents that can bind mono- or bifunctionally to guanines in DNA. Mustard HN1 is considered a monofunctional analog of bifunctional mustard HN2 (mechlorethamine). Escherichia coli K12 mutant strains deficient in nucleotide excision repair (NER) or base excision repair (BER) were submitted to increasing concentrations of HN2 or HN1, and the results revealed that damage induced by each chemical demands different DNA repair pathways. Damage induced by HN2 demands the activity of NER with a minor requirement of the BER pathway, while HN1 damage repair depends on BER action, without any requirement of NER function. Taken together, our data suggest that HN1 and HN2 seem to induce different types of damage, since their repair depends on distinct pathways in E. coli.
Collapse
Affiliation(s)
- T A M De Alencar
- Lab. Radiobiologia Molecular, Programa de Biologia Molecular e Estrutural, Instituto de Biofísica Carlos Chagas Filho-UFRJ, Centro de Ciências da Saúde, Bloco G, 21941-540 Rio de Janeiro, RJ, Brazil
| | | | | |
Collapse
|
19
|
Lage C, de Pádula M, de Alencar TAM, da Fonseca Gonçalves SR, da Silva Vidal L, Cabral-Neto J, Leitão AC. New insights on how nucleotide excision repair could remove DNA adducts induced by chemotherapeutic agents and psoralens plus UV-A (PUVA) in Escherichia coli cells. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2003; 544:143-57. [PMID: 14644316 DOI: 10.1016/j.mrrev.2003.06.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Chemotherapeutic agents such as mitomycin C or nitrogen mustards induce DNA inter-strand cross-links (ICL) and are highly toxic, thus constituting an useful tool to treat some human degenerative diseases, such as cancer. Additionally, psoralens plus UV-A (PUVA), which also induce ICL, find use in treatment of patients afflicted with psoriasis and vitiligo. The repair of DNA ICL generated by different molecules involves a number of multi-step DNA repair pathways. In bacteria, as in eukaryotic cells, if DNA ICL are not tolerated or repaired via nucleotide excision repair (NER), homologous recombination or translesion synthesis pathways, these DNA lesions may lead to mutations and cell death. Herein, we bring new insights to the role of Escherichia coli nucleotide excision repair genes uvrA, uvrB and uvrC in the repair of DNA damage induced by some chemotherapeutic agents and psoralen derivatives plus UV-A. These new observations point to a novel role for the UvrB protein, independent of its previously described role in the Uvr(A)BC complex, which could be specific for repair of monoadducts, intra-strand biadducts and/or ICL.
Collapse
Affiliation(s)
- Claudia Lage
- Laboratório de Radiobiologia Molecular, Instituto de Biofísica Carlos Chagas Filho, Bloco G, Centro de Ciencias da Saude, Universidade de Federal do Rio de Janeiro, 21949-900 Rio de Janeiro, RJ, Brazil
| | | | | | | | | | | | | |
Collapse
|
20
|
Aguilar-Mahecha A, Hales BF, Robaire B. Chronic cyclophosphamide treatment alters the expression of stress response genes in rat male germ cells. Biol Reprod 2002; 66:1024-32. [PMID: 11906922 DOI: 10.1095/biolreprod66.4.1024] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Increases in the survival rate of men treated with chemotherapeutic drugs and their desire to have children precipitate concerns about the effects of these drugs on germ cells. Azoospermia, oligospermia, and infertility are common outcomes resulting from treatment with cyclophosphamide, an alkylating agent. Exposure of male rats to cyclophosphamide results in dose-dependent and time-specific adverse effects on progeny outcome. Elucidation of the effects of chronic low-dose cyclophosphamide treatment on the expression of stress response genes in male germ cells may provide insight into the mechanisms underlying such adverse effects. Male rats were gavaged with saline or cyclophosphamide (6 mg/kg) for 4-5 wk; pachytene spermatocytes, round spermatids, and elongating spermatids were isolated; RNA was extracted and probed on cDNA arrays containing 216 cDNAs. After saline treatment, 125 stress response genes were expressed in pachytene spermatocytes (57% of genes studied), 122 in round spermatids (56%), and 83 in elongating spermatids (38%). Cyclophosphamide treatment reduced the number of genes detected in all germ cell types. The predominant effect of chronic cyclophosphamide exposure was to decrease the expression level of genes in pachytene spermatocytes (34% of genes studied), round spermatids (29%), and elongating spermatids (4%). In elongating spermatids only, drug treatment increased the expression of 8% of the genes studied. The expression profiles of genes involved in DNA repair, posttranslational modification, and antioxidant defense in male germ cells were altered by chronic cyclophosphamide treatment. We hypothesize that the effects of cyclophosphamide exposure on germ cell gene expression during spermatogenesis may have adverse consequences on male fertility and progeny outcome.
Collapse
Affiliation(s)
- Adriana Aguilar-Mahecha
- Department of Pharmacology and Therapeutics, McGill University, 3655 Promenade Sir-William-Osler, Montreal, Quebec, Canada H3G 1Y6
| | | | | |
Collapse
|
21
|
Kapuscinski J, Ardelt B, Piosik J, Zdunek M, Darzynkiewicz Z. The modulation of the DNA-damaging effect of polycyclic aromatic agents by xanthines. Part I. Reduction of cytostatic effects of quinacrine mustard by caffeine. Biochem Pharmacol 2002; 63:625-34. [PMID: 11992630 DOI: 10.1016/s0006-2952(01)00904-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Recently, accumulated statistical data indicate the protective effect of caffeine consumption against several types of cancer diseases. There are also reports about protective effect of caffeine and other xanthines against tumors induced by polycyclic aromatic hydrocarbons. One of the explanations is based on biological activation of such carcinogens by cytochromes that are also known for metabolism of caffeine. However, there is also numerous data indicating reverse effect on cytotoxicity of anticancer drugs that inhibit the action of topoisomerase I (e.g. Camptothecin or Topotecan) and topoisomerase II inhibitors (e.g. Doxorubicin, Mitoxantrone or mAMSA). In this work we tested the hypothesis that the caffeine protective effect is the result of sequestering of aromatic mutagens by formation of stacking (pi-pi) complexes. As the models for the study we have chosen two well-known mutagens, that do not require metabolical activation: quinacrine mustard(QM, aromatic, heterocyclic nitrogen mustard) and mechlorethamine (NM2, aliphatic nitrogen mustard). The flow cytometry study of these agents' action on the cell cycle of HL-60 cells indicated that caffeine prevents the cytotoxic action of QM, but not that of NM2. The formations of stacking complexes of QM with caffeine were confirmed by light absorption, calorimetric measurements and by molecular modeling calculation. Using the statistical thermodynamics calculations we calculated the "neighborhood" association constant (K(AC)=59+/-2M(-1)) and enthalpy change (DeltaH(0')=-116cal mol(-1)); the favorable entropy change of complex formation (DeltaS(0')=7.72cal mol(-1)K(-1), due to release of several water molecules, associated with components in the process of complex formation). The Gibbs' free energy change of QM-CAF formation is DeltaG(0')=-2.41kcal mol(-1). We were unable to detect any interaction between NM2 and caffeine either by spectroscopic or calorimetric measurement. In order to establish, whether the intercalation of QM plays any role in cytotoxic effect we tested, as a control, non-alkylatiatig, but also intercalating QM derivative-quinacrine (Q). The later had no cytostatic effect on HL-60 cell even at there order of higher concentration than QM or NM2 but, similar to QM forms (which we demonstrated) stacking complexes with caffeine (K(AC)=75+/-3M(-1)). These results strongly indicate, that the attenuating effect of caffeine on cytotoxic or mutagenic effects of some mutagens, is not the results of metabolic processes in the cells, but simply the physicochemical process of sequestering of aromatic molecules (potential carcinogens or mutagens) by formation of stacking complexes with them. The caffeine may then act as the "interceptor" of potential carcinogens (especially in the upper part of digesting track where its concentration can reach the concentration of mM level). There is, however, no indication either in the literature or in our experiments that xanthines can reverse the damage to nucleic acids when the damage to DNA has already occurred.
Collapse
Affiliation(s)
- Jan Kapuscinski
- Laboratory of Biophysical Chemistry, Department of Molecular and Cellular Biology, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Kladki 24, 80-822, Gdansk, Poland.
| | | | | | | | | |
Collapse
|
22
|
Ferguson LR, Liu AP, Denny WA, Cullinane C, Talarico T, Phillips DR. Transcriptional blockages in a cell-free system by sequence-selective DNA alkylating agents. Chem Biol Interact 2000; 126:15-31. [PMID: 10826651 DOI: 10.1016/s0009-2797(00)00144-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
There is considerable interest in DNA sequence-selective DNA-binding drugs as potential inhibitors of gene expression. Five compounds with distinctly different base pair specificities were compared in their effects on the formation and elongation of the transcription complex from the lac UV5 promoter in a cell-free system. All were tested at drug levels which killed 90% of cells in a clonogenic survival assay. Cisplatin, a selective alkylator at purine residues, inhibited transcription, decreasing the full-length transcript, and causing blockage at a number of GG or AG sequences, making it probable that intrastrand crosslinks are the blocking lesions. A cyclopropylindoline known to be an A-specific alkylator also inhibited transcription, with blocks at adenines. The aniline mustard chlorambucil, that targets primarily G but also A sequences, was also effective in blocking the formation of full-length transcripts. It produced transcription blocks either at, or one base prior to, AA or GG sequences, suggesting that intrastrand crosslinks could again be involved. The non-alkylating DNA minor groove binder Hoechst 33342 (a bisbenzimidazole) blocked formation of the full-length transcript, but without creating specific blockage sites. A bisbenzimidazole-linked aniline mustard analogue was a more effective transcription inhibitor than either chlorambucil or Hoechst 33342, with different blockage sites occurring immediately as compared with 2 h after incubation. The blockages were either immediately prior to AA or GG residues, or four to five base pairs prior to such sites, a pattern not predicted from in vitro DNA-binding studies. Minor groove DNA-binding ligands are of particular interest as inhibitors of gene expression, since they have the potential ability to bind selectively to long sequences of DNA. The results suggest that the bisbenzimidazole-linked mustard does cause alkylation and transcription blockage at novel DNA sites. in addition to sites characteristic of untargeted mustards.
Collapse
Affiliation(s)
- L R Ferguson
- Auckland Cancer Society Research Centre, Faculty of Medicine and Health Science, The University of Auckland, New Zealand.
| | | | | | | | | | | |
Collapse
|
23
|
Chen X, Cullinane C, Gray PJ, Phillips DR. DNA damage by nitrogen mustard in a gene containing multiple Sp1-binding sites. Mutat Res 1999; 445:45-54. [PMID: 10521690 DOI: 10.1016/s1383-5718(99)00114-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The human cytochrome c(1) gene TATA-less promoter contains 10 Sp1-binding elements that regulate the activation of transcription of this gene. Quantitative PCR was used to show that nitrogen mustard induces DNA lesions within this Sp1-binding region following exposure of HeLa cells to clinical levels of the drug. Alkylation of the cytochrome c(1) gene in HeLa cells increased with reaction time up to 4 h following exposure to nitrogen mustard, with 50% of the lesions (approximately 0.8/kb) forming within 1 h. An Sp1 competition assay showed that nitrogen mustard inhibited the binding of Sp1 to the promoter region of the cytochrome c(1) gene in HeLa cells. These results show that nitrogen mustard-induced damage to Sp1-binding sites may contribute to the toxicity of this compound by interfering with the activation of specific genes.
Collapse
Affiliation(s)
- X Chen
- Department of Biochemistry, La Trobe University, Bundoora, Victoria, 3083, Australia
| | | | | | | |
Collapse
|
24
|
Chen XM, Gray PJ, Cullinane C, Phillips DR. Differential sensitivity of transcription factors to mustard-damaged DNA. Chem Biol Interact 1999; 118:51-67. [PMID: 10227578 DOI: 10.1016/s0009-2797(98)00117-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nitrogen mustard (bis(2-chloroethyl) methylamine, HN2) inhibited the binding of upstream factors Sp1 and AP2 to their consensus sequences. At concentrations where 50% of the consensus sequence DNA contained at least one lesion, HN2 inhibited formation of the Sp1 complex by 37% (40 microM HN2) and the AP2 complex by 40% (50 microM HN2). The binding of the TATA binding protein (TBP) to the TATA element was also inhibited by HN2, whereas sulphur mustard and the monofunctional sulphur mustard 2-chloroethyl ethyl sulphide (CEES) resulted in a disproportional extent of inhibition with respect to the level of alkylation. The level of alkylation of the TBP oligonucleotide varied significantly at 100 microM drug, with 80, 42 and 15% of HN2, sulphur mustard and CEES, respectively. However, this level of alkylation inhibited formation of the TBP-DNA complex by 70, 70 and 45%, respectively. This differential sensitivity of transcription factors to mustard-induced DNA damage therefore appears to reside dominantly in the stereochemical differences between the specific mustard lesions.
Collapse
Affiliation(s)
- X M Chen
- Department of Biochemistry, La Trobe University, Bundoora, Victoria, Australia
| | | | | | | |
Collapse
|
25
|
Fischer KM. Expanded (CAG)n, (CGG)n and (GAA)n trinucleotide repeat microsatellites, and mutant purine synthesis and pigmentation genes cause schizophrenia and autism. Med Hypotheses 1998; 51:223-33. [PMID: 9792200 DOI: 10.1016/s0306-9877(98)90080-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Unstable (CAG)n trinucleotide repeat microsatellites are hypothesized to cause schizophrenia. The (CAG)n microsatellite of dominant spinal cerebellar ataxia type 1 (SCA1) is a candidate schizophrenia gene. Autism results from expansions of (CGG)n and (GAA)n trinucleotide repeat stretches at fragile X syndrome (FRAXA), and the recessive Friedreich's ataxia (FA). Dominant ataxia genes may cause schizophrenia and recessive ataxia genes may cause autism. Syndromes with autism show purine synthesis defects (PSDs) and/or pigmentation defects (PDs). Autism is caused by very lengthy expansions of (CAG)n, (CGG)n and (GAA)n repeats, while schizophrenia results from much smaller (CAG)n and (CGG)n repeat expansions.
Collapse
|
26
|
Abstract
Ternary complexes of DNA-dependent RNA polymerase with its DNA template and nascent transcript are central intermediates in transcription. In recent years, several unusual biochemical reactions have been discovered that affect the progression of RNA polymerase in ternary complexes through various transcription units. These reactions can be signaled intrinsically, by nucleic acid sequences and the RNA polymerase, or extrinsically, by protein or other regulatory factors. These factors can affect any of these processes, including promoter proximal and promoter distal pausing in both prokaryotes and eukaryotes, and therefore play a central role in regulation of gene expression. In eukaryotic systems, at least two of these factors appear to be related to cellular transformation and human cancers. New models for the structure of ternary complexes, and for the mechanism by which they move along DNA, provide plausible explanations for novel biochemical reactions that have been observed. These models predict that RNA polymerase moves along DNA without the constant possibility of dissociation and consequent termination. A further prediction of these models is that the polymerase can move in a discontinuous or inchworm-like manner. Many direct predictions of these models have been confirmed. However, one feature of RNA chain elongation not predicted by the model is that the DNA sequence can determine whether the enzyme moves discontinuously or monotonically. In at least two cases, the encounter between the RNA polymerase and a DNA block to elongation appears to specifically induce a discontinuous mode of synthesis. These findings provide important new insights into the RNA chain elongation process and offer the prospect of understanding many significant biological regulatory systems at the molecular level.
Collapse
Affiliation(s)
- S M Uptain
- Department of Molecular and Cell Biology, University of California at Berkeley 94720, USA.
| | | | | |
Collapse
|
27
|
Gniazdowski M, Cera C. The Effects of DNA Covalent Adducts on in Vitro Transcription. Chem Rev 1996; 96:619-634. [PMID: 11848767 DOI: 10.1021/cr940049l] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Marek Gniazdowski
- Department of General Chemistry, Medical University of Lodz, ul.Lindleya 6, 90-131 Lodz, Poland, and Department of Pharmaceutical Sciences, University of Padova, via Marzolo 5, 35131 Padova, Italy
| | | |
Collapse
|
28
|
Transcriptional assay for probing molecular aspects of drug-DNA interactions. ADVANCES IN DNA SEQUENCE-SPECIFIC AGENTS 1996. [DOI: 10.1016/s1067-568x(96)80007-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
|
29
|
Abstract
The bifunctional sulphur mustard (bis-(2-chloroethyl)sulphide, HD) and its monofunctional analogue (2-chloroethyl ethyl sulphide, CEES) are both vesicants. In this study, both mustards were shown to rapidly alkylate the AP2 consensus binding sequence incorporated in a 26mer oligonucleotide. The reaction was essentially complete within 10 min under the conditions employed in this study and -95% of the oligonucleotides were alkylated at least once using 500 microM HD and 1 mM CEES. Progressive alkylation of the consensus sequence was parallelled by a decrease in transcription factor binding. Under reaction conditions which alkylated approximately 95% of the oligonucleotides at least once, the binding of cloned human AP2 was reduced by 93 and 76% by HD and CEES, respectively, compared with control values. The interference with binding is a result of alkylation of the DNA and not damage to the transcription factor by mustard or its hydrolysis products. Interference with transcription factor binding would be expected to have a profound influence on the ability of the cell to function normally and to respond to DNA damage and may contribute significantly to the skin damage produced by these compounds.
Collapse
Affiliation(s)
- P J Gray
- Aeronautical and Maritime Research Laboratory, Defence Science and Technology Organisation, Melbourne, Australia
| |
Collapse
|
30
|
Masta A, Gray PJ, Phillips DR. Nitrogen mustard inhibits transcription and translation in a cell free system. Nucleic Acids Res 1995; 23:3508-15. [PMID: 7567463 PMCID: PMC307231 DOI: 10.1093/nar/23.17.3508] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Nitrogen mustard and its derivatives such as cyclophosphamide, chlorambucil and melphalan are widely used anti-cancer agents, despite their non-specific reaction mechanism. In this study, the effect of alkylation by nitrogen mustard of DNA and RNA (coding for a single protein) was investigated using both a translation system and a coupled transcription/translation system. When alkylated DNA was used as the template for coupled transcription and translation, a single translation product corresponding to the 62 kDa luciferase protein was synthesised. Production of the translated product encoded by this template was inhibited by mustard concentrations as low as 10 nM, and 50% inhibition occurred with 30 nM mustard. A primer extension assay employed to verify alkylation sites on the DNA revealed that all guanine residues on the DNA template are susceptible to alkylation by nitrogen mustard. Similarly, when alkylated RNA was used as the template for protein synthesis, the amount of the 62 kDa luciferase protein decreased with increasing mustard concentration and a range of truncated polypeptides was synthesised. Under these conditions 50% inhibition of translation occurred with approximately 300 nM mustard (i.e. approximately 10 times that required for similar inhibition using an alkylated DNA template). Furthermore, a gel mobility shift assay revealed that mustard alkylation of the RNA template results in the formation of a more stable retarded RNA complex. The functional activity of the luciferase protein decreased with alkylation of both the DNA and RNA templates, with a half-life of loss of activity of 1.1 h for DNA exposed to 50 nM mustard, and 0.5 h for RNA exposed to 50 microM mustard. The data presented support the notion that DNA is a critical molecule in the mode of action of mustards.
Collapse
Affiliation(s)
- A Masta
- School of Biochemistry, La Trobe University, Bundoora, Australia
| | | | | |
Collapse
|