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Tavladoraki P, Cervelli M, Antonangeli F, Minervini G, Stano P, Federico R, Mariottini P, Polticelli F. Probing mammalian spermine oxidase enzyme-substrate complex through molecular modeling, site-directed mutagenesis and biochemical characterization. Amino Acids 2011; 40:1115-26. [PMID: 20839014 DOI: 10.1007/s00726-010-0735-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Accepted: 08/26/2010] [Indexed: 10/19/2022]
Abstract
Spermine oxidase (SMO) and acetylpolyamine oxidase (APAO) are FAD-dependent enzymes that are involved in the highly regulated pathways of polyamine biosynthesis and degradation. Polyamine content is strictly related to cell growth, and dysfunctions in polyamine metabolism have been linked with cancer. Specific inhibitors of SMO and APAO would allow analyzing the precise role of these enzymes in polyamine metabolism and related pathologies. However, none of the available polyamine oxidase inhibitors displays the desired characteristics of selective affinity and specificity. In addition, repeated efforts to obtain structural details at the atomic level on these two enzymes have all failed. In the present study, in an effort to better understand structure-function relationships, SMO enzyme-substrate complex has been probed through a combination of molecular modeling, site-directed mutagenesis and biochemical studies. Results obtained indicate that SMO binds spermine in a similar conformation as that observed in the yeast polyamine oxidase FMS1-spermine complex and demonstrate a major role for residues His82 and Lys367 in substrate binding and catalysis. In addition, the SMO enzyme-substrate complex highlights the presence of an active site pocket with highly polar characteristics, which may explain the different substrate specificity of SMO with respect to APAO and provide the basis for the design of specific inhibitors for SMO and APAO.
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Affiliation(s)
- Paraskevi Tavladoraki
- Department of Biology, University Roma Tre, Viale Guglielmo Marconi 446, 00146, Rome, Italy
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Schuster I, Bernhardt R. Interactions of natural polyamines with mammalian proteins. Biomol Concepts 2011; 2:79-94. [DOI: 10.1515/bmc.2011.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
AbstractThe ubiquitously expressed natural polyamines putrescine, spermidine, and spermine are small, flexible cationic compounds that exert pleiotropic actions on various regulatory systems and, accordingly, are essentially involved in diverse life functions. These roles of polyamines result from their capability to interact with negatively charged regions of all major classes of biomolecules, which might act in response by changing their structures and functions. The present review deals with polyamine-protein interactions, thereby focusing on mammalian proteins. We discuss the various modes in which polyamines can interact with proteins, describe major types of affected functions illustrated by representative examples of involved proteins, and support information with respective structural evidence from elucidated three-dimensional structures. A specific focus is put on polyamine interactions at protein surfaces that can modulate the aggregation of proteins to organized structural networks as well as to toxic aggregates and, moreover, can play a role in important transient protein-protein interactions.
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Affiliation(s)
- Inge Schuster
- 1Institute for Theoretical Chemistry, University Vienna, A-1090 Vienna, Austria
| | - Rita Bernhardt
- 2Institute of Biochemistry, Saarland University, Campus B2.2, D-66123 Saarbrücken, Germany
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LEE SB, PARK JH, FOLK J, DECK JA, PEGG AE, SOKABE M, FRASER CS, PARK MH. Inactivation of eukaryotic initiation factor 5A (eIF5A) by specific acetylation of its hypusine residue by spermidine/spermine acetyltransferase 1 (SSAT1). Biochem J 2011; 433:205-13. [PMID: 20942800 PMCID: PMC3003598 DOI: 10.1042/bj20101322] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
eIF5A (eukaryotic translation initiation factor 5A) is the only cellular protein containing hypusine [Nϵ-(4-amino-2-hydroxybutyl)lysine]. eIF5A is activated by the post-translational synthesis of hypusine and the hypusine modification is essential for cell proliferation. In the present study, we report selective acetylation of the hypusine and/or deoxyhypusine residue of eIF5A by a key polyamine catabolic enzyme SSAT1 (spermidine/spermine-N1-acetyltransferase 1). This enzyme normally catalyses the N1-acetylation of spermine and spermidine to form acetyl-derivatives, which in turn are degraded to lower polyamines. Although SSAT1 has been reported to exert other effects in cells by its interaction with other cellular proteins, eIF5A is the first target protein specifically acetylated by SSAT1. Hypusine or deoxyhypusine, as the free amino acid, does not act as a substrate for SSAT1, suggesting a macromolecular interaction between eIF5A and SSAT1. Indeed, the binding of eIF5A and SSAT1 was confirmed by pull-down assays. The effect of the acetylation of hypusine on eIF5A activity was assessed by comparison of acetylated with non-acetylated bovine testis eIF5A in the methionyl-puromycin synthesis assay. The loss of eIF5A activity by this SSAT1-mediated acetylation confirms the strict structural requirement for the hypusine side chain and suggests a possible regulation of eIF5A by hypusine acetylation/deacetylation.
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Affiliation(s)
- Seung Bum LEE
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892 USA
| | - Jong Hwan PARK
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892 USA
| | - J.E. FOLK
- Chemical Biology Research Branch, National Institute of Drug Abuse and National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, 20892 USA
| | - Jason A. DECK
- Chemical Biology Research Branch, National Institute of Drug Abuse and National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, 20892 USA
| | - Anthony E. PEGG
- Department of Cellular and Molecular Physiology, Milton S. Hershey Medical Center, Pennsylvania State University, Hershey, PA, 17033 USA
| | - Masaaki SOKABE
- Department of Biochemistry and Molecular Medicine, University of California, Davis, CA 95616
| | - Christopher S. FRASER
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616
| | - Myung Hee PARK
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892 USA
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Lee SB, Park JH, Woster PM, Casero RA, Park MH. Suppression of exogenous gene expression by spermidine/spermine N1-acetyltransferase 1 (SSAT1) cotransfection. J Biol Chem 2010; 285:15548-15556. [PMID: 20212040 DOI: 10.1074/jbc.m109.092007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Spermidine/spermine N(1)-acetyltransferase 1 (SSAT1), which catalyzes the N(1)-acetylation of spermidine and spermine to form acetyl derivatives, is a rate-limiting enzyme in polyamine catabolism. We now report a novel activity of transiently transfected SSAT1 in suppressing the exogenous expression of other proteins, i.e. green fluorescent protein (GFP) or GFP-eIF5A. Spermidine/spermine N(1)-acetyltransferase 2 (SSAT2) or inactive SSAT1 mutant enzymes (R101A or R101K) were without effect. The loss of exogenous gene expression is not due to accelerated protein degradation, because various inhibitors of proteases, lysosome, or autophagy did not mitigate the effects. This SSAT1 effect cannot be attributed to the depletion of overall cellular polyamines or accumulation of N(1)-acetylspermidine (N(1)-AcSpd) because of the following: (i) addition of putrescine, spermidine, spermine, or N(1)-AcSpd did not restore the expression of GFP or GFP-eIF5A; (ii) depletion of cellular polyamines with alpha-difluoromethylornithine, an inhibitor of ornithine decarboxylase, did not inhibit exogenous gene expression; and (iii) N(1),N(11)-bis(ethyl)norspermine caused a drastic depletion of cellular polyamines through induction of endogenous SSAT1 but did not block exogenous gene expression. SSAT1 transient transfection did not affect stable expression of GFP, and stably expressed SSAT1 did not affect exogenous expression of GFP, suggesting that only transiently (episomally) expressed SSAT1 blocks exogenous (episomal) expression of other proteins. SSAT1 may regulate exogenous gene expression by blocking steps involved in transcription/translation from an episomal vector by targeting non-polyamine substrate(s) critical for this pathway.
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Affiliation(s)
- Seung Bum Lee
- Oral and Pharyngeal Cancer Branch, NIDCR, National Institutes of Health, Bethesda, Maryland 20892
| | - Jong Hwan Park
- Oral and Pharyngeal Cancer Branch, NIDCR, National Institutes of Health, Bethesda, Maryland 20892
| | - Patrick M Woster
- Department of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan 48201
| | - Robert A Casero
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21231
| | - Myung Hee Park
- Oral and Pharyngeal Cancer Branch, NIDCR, National Institutes of Health, Bethesda, Maryland 20892.
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Yamamichi S, Nishitani M, Nishimura N, Matsushita Y, Hasumi K. Polyamine-promoted autoactivation of plasma hyaluronan-binding protein. J Thromb Haemost 2010; 8:559-66. [PMID: 19817990 DOI: 10.1111/j.1538-7836.2009.03641.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Plasma hyaluronan-binding protein (PHBP), a protease implicated in extracellular proteolysis, consists of multiple domains: an N-terminal region (NTR), three epidermal growth factor (EGF)-like domains, a kringle domain, and a protease domain. PHBP circulates as a single-chain proenzyme (pro-PHBP), which is converted to an active, two-chain form through autoproteolysis. OBJECTIVE To understand the mechanism of autoactivation. Here, we report that polyamine induces the formation of pro-PHBP autoactivation complex, in which an intermolecular interaction between NTR and the third EGF-like domain (E3) plays a role. METHODS Using a series of pro-PHBP mutants that partially lack functional domains, polyamine-induced pro-PHBP autoactivation was investigated in terms of enzyme activity, protein interaction, and inhibition by carminic acid, an anthraquinone compound identified in this study. RESULTS Polyamine enhanced intermolecular binding of pro-PHBP, but not of mutant pro-PHBP that partially lacked NTR (DeltaN). Carminic acid inhibited intermolecular pro-PHBP binding and specifically abolished polyamine-induced autoactivation. NTR bound to pro-PHBP and DeltaN, but its binding was minimal to a mutant that lacked E3. The NTR-DeltaN binding was inhibited by a combination of polyamine and carminic acid, but each compound alone was ineffective. CONCLUSIONS We infer from the data that (i) polyamine modulates intramolecular NTR-E3 interaction to allow intermolecular binding between NTR and E3 in another pro-PHBP molecule to form an autoactivation complex, and (ii) carminic acid inhibits polyamine-modulated intermolecular NTR-E3 binding. Polyamine concentrations are higher in cells and tissues with inflammation and malignancy. Polyamine leakage from legions through cell death or tissue injury may account for physiologically relevant pro-PHBP activation.
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Affiliation(s)
- S Yamamichi
- Department of Applied Biological Science, Tokyo Noko University, 3-5-8 Saiwaicho, Fuchu-shi, Tokyo 183-8509, Japan
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Bjelaković G, Stojanović I, Jevtović Stoimenov T, Pavlović D, Kocić G, Rossi S, Tabolacci C, Nikolić J, Sokolović D, Bjelakovic L. Metabolic correlations of glucocorticoids and polyamines in inflammation and apoptosis. Amino Acids 2010; 39:29-43. [PMID: 20169375 DOI: 10.1007/s00726-010-0489-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2009] [Accepted: 01/16/2010] [Indexed: 01/28/2023]
Abstract
Glucocorticoid hormones (GC) are essential in all aspects of human health and disease. Their anti-inflammatory and immunosuppressive properties are reasons for therapeutic application in several diseases. GC suppress immune activation and uncontrolled overproduction and release of cytokines. GC inhibit the release of pro-inflammatory cytokines and stimulate the production of anti-inflammatory cytokines. Investigation of GC's mechanism of action, suggested that polyamines (PA) may act as mediators or messengers of their effects. Beside glucocorticoids, spermine (Spm) is one of endogenous inhibitors of cytokine production. There are many similarities in the metabolic actions of GC and PA. The major mechanism of GC effects involves the regulation of gene expression. PA are essential for maintaining higher order organization of chromatin in vivo. Spermidine and Spm stabilize chromatin and nuclear enzymes, due to their ability to form complexes with negatively charged groups on DNA, RNA and proteins. Also, there is an increasing body of evidence that GC and PA change the chromatin structure especially through acetylation and deacetylation of histones. GC display potent immunomodulatory activities, including the ability to induce T and B lymphocyte apoptosis, mediated via production of reactive oxygen species (ROS) in the mitochondrial pathway. The by-products of PA catabolic pathways (hydrogen peroxide, amino aldehydes, acrolein) produce ROS, well-known cytotoxic agents involved in programmed cell death (PCD) or apoptosis. This review is an attempt in the better understanding of relation between GC and PA, naturally occurring compounds of all eukaryotic cells, anti-inflammatory and apoptotic agents in physiological and pathological conditions connected to oxidative stress or PCD.
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Affiliation(s)
- G Bjelaković
- Faculty of Medicine, Institute of Biochemistry, University of Nis, Nis, Serbia.
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Abstract
Increased polyamine synthesis and inflammation have long been associated with intraepithelial neoplasia, which are risk factors for cancer development in humans. Targeting polyamine metabolism (by use of polyamine synthesis inhibitors or polyamine catabolism activators) and inflammation (by use of nonsteroidal anti-inflammatory drugs) has been studied for many cancers, including colon, prostate, and skin. Genetic epidemiology results indicate that a genetic variant associated with the expression of a polyamine biosynthetic gene is associated with risk of colon and prostate cancers. A clinical trial of difluoromethylornithine (DFMO), a selective inhibitor of polyamine synthesis, showed that the 1 year treatment duration reduced prostate volume and serum prostate-specific antigen doubling time in men with a family history of prostate cancer. A second, clinical trial of DFMO in combination with sulindac, a NSAID in patients with prior colon polyps found that the 3-year treatment was associated with a 70% reduction of all, and over a 90% reduction of advanced and/or multiple metachronous colon adenomas. In this chapter, we discuss that similar combination prevention strategies of targeting polyamines and inflammation can be effective in reducing risk factors associated with the development of human cancers.
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Gerner EW, Meyskens FL. Combination chemoprevention for colon cancer targeting polyamine synthesis and inflammation. Clin Cancer Res 2009; 15:758-61. [PMID: 19188144 DOI: 10.1158/1078-0432.ccr-08-2235] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Increased polyamine synthesis and inflammation have long been associated with colon carcinogenesis in both preclinical models and in humans. Recent experimental studies suggest that polyamines may be mechanistically involved in colonic inflammatory processes. Genetic epidemiology results indicate that a single nucleotide polymorphism influencing the expression of a polyamine biosynthetic gene is associated with both risk of colon polyp occurrence and recurrence, and the response to aspirin as a polyp preventive agent. A prospective, randomized, placebo-controlled clinical trial of combination difluoromethylornithine, a selective inhibitor of polyamine synthesis, and sulindac, a nonsteroidal anti-inflammatory drug, found that the 3-year treatment was associated with a 70% reduction of recurrence of all adenomas, and over a 90% reduction of recurrence of advanced and/or multiple adenomas, without evidence of serious toxicities. This proof-of-principle trial indicates that targeting polyamine synthesis and inflammation can be an effective strategy for preventing the occurrence of the advanced and/or multiple adenomas that are most closely associated with the development of colon cancers in humans.
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Affiliation(s)
- Eugene W Gerner
- The University of Arizona, Arizona Cancer Center, Tucson, Arizona 85724, USA.
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59
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Zhu S, Ashok M, Li J, Li W, Yang H, Wang P, Tracey KJ, Sama AE, Wang H. Spermine protects mice against lethal sepsis partly by attenuating surrogate inflammatory markers. Mol Med 2009; 15:275-82. [PMID: 19593412 DOI: 10.2119/molmed.2009.00062] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Accepted: 04/29/2009] [Indexed: 11/06/2022] Open
Abstract
The pathogenesis of sepsis is partly attributable to dysregulated inflammatory response mediated by pathogen-associated molecular patterns (PAMPs) (for example, endotoxin) and damage-associated molecular patterns (DAMPs) (for example, high-mobility group box 1 [HMGB1]). An endogenous ubiquitous polyamine, spermine, inhibits endotoxin-induced cytokine release in vitro, but its capacities to attenuate sepsis- and HMGB1-induced inflammatory responses was previously unknown. We thus tested the hypothesis that spermine protects mice against lethal sepsis by attenuating sepsis-induced local and systemic inflammatory responses. Intraperitoneal (i.p.) administration of spermine (10 mg/kg, twice daily, for 3 d) conferred a significant protection against lethal sepsis. The protective effects were associated with a significant reduction in peritoneal and serum levels of several surrogate markers of sepsis (for example, Interleukin-6 [IL-6], keratinocyte-derived chemokine [KC], monocytes chemoattractant protein-1 [MCP-1], macrophage inflammatory protein-2 [MIP-2], tissue inhibitor of metalloproteinase-1 [TIMP-1], soluble tumor necrosis factor-alpha receptor I [sTNFRI], and soluble tumor necrosis factor-alpha receptor II [sTNFRII]) during a late stage of sepsis. In vitro, spermine effectively inhibited HMGB1-induced release of the above surrogate markers in peritoneal macrophages. Thus, spermine confers protection against lethal sepsis partly by attenuating sepsis- and HMGB1-induced inflammatory responses.
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Affiliation(s)
- Shu Zhu
- Department of Emergency Medicine, North Shore University Hospital, New York University School of Medicine, Manhasset, New York 11030, United States of America
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Current world literature. Ageing: biology and nutrition. Curr Opin Clin Nutr Metab Care 2009; 12:95-100. [PMID: 19057195 DOI: 10.1097/mco.0b013e32831fd97a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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García-Faroldi G, Sánchez-Jiménez F, Fajardo I. The polyamine and histamine metabolic interplay in cancer and chronic inflammation. Curr Opin Clin Nutr Metab Care 2009; 12:59-65. [PMID: 19057189 DOI: 10.1097/mco.0b013e328314b9ac] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
PURPOSE OF REVIEW To provide an update on the major research contributing to deciphering the metabolic interplay of polyamines/histamine and its impact in cancer and chronic inflammation. RECENT FINDINGS The most recent and relevant findings that might reflect a link between the polyamines/histamine metabolic interplay and the development of cancer and chronic inflammation-related diseases include: the observation that histamine catabolism is downregulated in the colonic mucosa of patients with colonic adenoma; the finding that some polyamine and histamine-related metabolites are different between a breast cancer cell line and a reference mammary epithelial cell line; and the demonstration of the critical role that mast cells (a cell type in which the polyamine/histamine metabolic interplay has been confirmed) play in the development of pancreatic tumors. There is still, however, a lack of specific studies elucidating the exact contribution of the polyamine/histamine metabolic interplay in these clinical settings. SUMMARY In mammalian cells, a polyamine/histamine metabolic interplay has been extensively proven; however, its ultimate effect on human health largely depends on the cell type and environment. Information on this topic is currently fragmented in the literature. In order to develop efficient intervention strategies, it will be necessary to establish an integrated and holistic view of the role of the polyamine/histamine metabolic interplay in each pathological state.
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Affiliation(s)
- Gianni García-Faroldi
- Department of Molecular Biology and Biochemistry, Faculty of Sciences, University of Málaga, and CIBER de Enfermedades Raras, Campus de Teatinos s/n, Málaga, Spain
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Murray-Stewart T, Wang Y, Goodwin A, Hacker A, Meeker A, Casero RA. Nuclear localization of human spermine oxidase isoforms - possible implications in drug response and disease etiology. FEBS J 2008; 275:2795-806. [PMID: 18422650 PMCID: PMC3631774 DOI: 10.1111/j.1742-4658.2008.06419.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The recent discovery of the direct oxidation of spermine via spermine oxidase (SMO) as a mechanism through which specific antitumor polyamine analogues exert their cytotoxic effects has fueled interest in the study of the polyamine catabolic pathway. A major byproduct of spermine oxidation is H2O2, a source of toxic reactive oxygen species. Recent targeted small interfering RNA studies have confirmed that SMO-produced reactive oxygen species are directly responsible for oxidative stress capable of inducing apoptosis and potentially mutagenic DNA damage. In the present study, we describe a second catalytically active splice variant protein of the human spermine oxidase gene, designated SMO5, which exhibits substrate specificities and affinities comparable to those of the originally identified human spermine oxidase-1, SMO/PAOh1, and, as such, is an additional source of H2O2. Importantly, overexpression of either of these SMO isoforms in NCI-H157 human non-small cell lung carcinoma cells resulted in significant localization of SMO protein in the nucleus, as determined by confocal microscopy. Furthermore, cell lines overexpressing either SMO/PAOh1 or SMO5 demonstrated increased spermine oxidation in the nucleus, with accompanying alterations in individual nuclear polyamine concentrations. This increased oxidation of spermine in the nucleus therefore increases the production of highly reactive H2O2 in close proximity to DNA, as well as decreases nuclear spermine levels, thus altering the protective roles of spermine in free radical scavenging and DNA shielding, and resulting in an overall increased potential for oxidative DNA damage in these cells. The results of these studies therefore have considerable significance both with respect to targeting polyamine oxidation as an antineoplastic strategy, and in regard to the potential role of spermine oxidase in inflammation-induced carcinogenesis.
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Affiliation(s)
- Tracy Murray-Stewart
- Department of Oncology, Johns Hopkins University School of Medicine and the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21231, USA
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