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Tantak MP, Sekhar V, Tao X, Zhai RG, Phanstiel O. Development of a Redox-Sensitive Spermine Prodrug for the Potential Treatment of Snyder Robinson Syndrome. J Med Chem 2021; 64:15593-15607. [PMID: 34695351 DOI: 10.1021/acs.jmedchem.1c00419] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Snyder Robinson Syndrome (SRS) is a rare disease associated with a defective spermine synthase gene and low intracellular spermine levels. In this study, a spermine replacement therapy was developed using a spermine prodrug that enters cells via the polyamine transport system. The prodrug was comprised of three components: a redox-sensitive quinone "trigger", a "trimethyl lock (TML)" aryl "release mechanism", and spermine. The presence of spermine in the design facilitated uptake by the polyamine transport system. The quinone-TML motifs provided a redox-sensitive agent, which upon intracellular reduction generated a hydroquinone, which underwent intramolecular cyclization to release free spermine and a lactone byproduct. Rewardingly, most SRS fibroblasts treated with the prodrug revealed a significant increase in intracellular spermine. Administering the spermine prodrug through feeding in a Drosophila model of SRS showed significant beneficial effects. In summary, a spermine prodrug is developed and provides a lead compound for future spermine replacement therapy experiments.
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Affiliation(s)
- Mukund P Tantak
- Department of Medical Education, College of Medicine, University of Central Florida, 12722 Research Parkway, Orlando, Florida 32826-3227, United States
| | - Vandana Sekhar
- Department of Medical Education, College of Medicine, University of Central Florida, 12722 Research Parkway, Orlando, Florida 32826-3227, United States
| | - Xianzun Tao
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, 1600 NW 10th Ave, Miami, Florida 33136, United States
| | - R Grace Zhai
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, 1600 NW 10th Ave, Miami, Florida 33136, United States
| | - Otto Phanstiel
- Department of Medical Education, College of Medicine, University of Central Florida, 12722 Research Parkway, Orlando, Florida 32826-3227, United States
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2
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Phanstiel O. An overview of polyamine metabolism in pancreatic ductal adenocarcinoma. Int J Cancer 2017; 142:1968-1976. [PMID: 29134652 DOI: 10.1002/ijc.31155] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 10/19/2017] [Accepted: 11/06/2017] [Indexed: 12/11/2022]
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest major cancers, with a five year survival rate of less than 8%. With current therapies only giving rise to modest life extension, new approaches are desperately needed. Even though targeting polyamine metabolism is a proven anticancer strategy, there are no reports, which thoroughly survey the literature describing the role of polyamine biosynthesis and transport in PDAC. This review seeks to fill this void by describing what is currently known about polyamine metabolism in PDAC and identifies new targets and opportunities to treat this disease. Due to the pleiotropic effects that polyamines play in cells, this review covers diverse areas ranging from polyamine metabolism (biosynthesis, catabolism and transport), as well as the potential role of polyamines in desmoplasia, autophagy and immune privilege. Understanding these diverse roles provides the opportunity to design new therapies to treat this deadly cancer via polyamine depletion.
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Affiliation(s)
- Otto Phanstiel
- Department of Medical Education, College of Medicine, University of Central Florida, Orlando, FL
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3
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Madan M, Patel A, Skruber K, Geerts D, Altomare DA, IV OP. ATP13A3 and caveolin-1 as potential biomarkers for difluoromethylornithine-based therapies in pancreatic cancers. Am J Cancer Res 2016; 6:1231-1252. [PMID: 27429841 PMCID: PMC4937730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 04/15/2016] [Indexed: 06/06/2023] Open
Abstract
The purpose of this paper was to better understand the role of polyamine transport in pancreatic cancers.This paper identifies potential biomarkers for assessing the relative tumor commitment to polyamine biosynthesis or transport. Cell lines with low polyamine import activity and low ATP13A3 protein levels appear committed to polyamine biosynthesis and required high concentrations of the polyamine biosynthesis inhibitor, difluoromethylornithine (DFMO) to inhibit their growth (e.g., AsPC-1 and Capan 1). In contrast, cell lines with high polyamine import activity and high ATP13A3 protein expression (e.g., L3.6pl) demonstrated a commitment to polyamine transport and required lower DFMO concentrations to inhibit their growth. Pancreatic cancer cell lines which were most sensitive to DFMO also gave the highest EC50 values for the polyamine transport inhibitors (PTIs) tested indicating that more PTI was needed to inhibit the active polyamine transport systems of these cell lines. Most significant is that the combination therapy of DFMO+PTI was efficacious against both cell types with the PTI showing low efficacy in cell lines with low polyamine transport activity and high efficacy in cell lines with high polyamine transport activity. High ATP13A3 protein expression and moderate to low Cav-1 protein expression was shown to be predictive of tumors which effectively escape DFMO via polyamine import. In summary, this report demonstrates for the first time the role of ATP13A3 in polyamine transport and its use as a potential biomarker along with Cav-1 to select tumors most susceptible to DFMO. These findings may help stratify patients in the ongoing clinical trials with DFMO-based therapies and help predict tumor response.
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Affiliation(s)
- Meenu Madan
- Department of Medical Education, University of Central Florida College of Medicine12722 Research Parkway, Orlando, Florida 32826, USA
| | - Arjun Patel
- Department of Medical Education, University of Central Florida College of Medicine12722 Research Parkway, Orlando, Florida 32826, USA
| | - Kristen Skruber
- Department of Medical Education, University of Central Florida College of Medicine12722 Research Parkway, Orlando, Florida 32826, USA
| | - Dirk Geerts
- Department of Pediatric Oncology, Erasmus University Medical Center, Dr. Molewaterplein 503015 GE Rotterdam, The Netherlands
| | - Deborah A Altomare
- Burnett School for Biomedical Sciences, University of Central Florida6900 Lake Nona Blvd., Orlando, FL 32827, USA
| | - Otto Phanstiel IV
- Department of Medical Education, University of Central Florida College of Medicine12722 Research Parkway, Orlando, Florida 32826, USA
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4
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Grossi M, Phanstiel O, Rippe C, Swärd K, Alajbegovic A, Albinsson S, Forte A, Persson L, Hellstrand P, Nilsson BO. Inhibition of Polyamine Uptake Potentiates the Anti-Proliferative Effect of Polyamine Synthesis Inhibition and Preserves the Contractile Phenotype of Vascular Smooth Muscle Cells. J Cell Physiol 2015; 231:1334-42. [PMID: 26529275 DOI: 10.1002/jcp.25236] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 11/02/2015] [Indexed: 12/29/2022]
Abstract
Increased vascular smooth muscle cell (VSMC) proliferation is a factor in atherosclerosis and injury-induced arterial (re) stenosis. Inhibition of polyamine synthesis by α-difluoro-methylornithine (DFMO), an irreversible inhibitor of ornithine decarboxylase, attenuates VSMC proliferation with high sensitivity and specificity. However, cells can escape polyamine synthesis blockade by importing polyamines from the environment. To address this issue, polyamine transport inhibitors (PTIs) have been developed. We investigated the effects of the novel trimer44NMe (PTI-1) alone and in combination with DFMO on VSMC polyamine uptake, proliferation and phenotype regulation. PTI-1 efficiently inhibited polyamine uptake in primary mouse aortic and human coronary VSMCs in the absence as well as in the presence of DFMO. Interestingly, culture with DFMO for 2 days substantially (>95%) reduced putrescine (Put) and spermidine (Spd) contents without any effect on proliferation. Culture with PTI-1 alone had no effect on either polyamine levels or proliferation rate, but the combination of both treatments reduced Put and Spd levels below the detection limit and inhibited proliferation. Treatment with DFMO for a longer time period (4 days) reduced Put and Spd below their detection limits and reduced proliferation, showing that only a small pool of polyamines is needed to sustain VSMC proliferation. Inhibited proliferation by polyamine depletion was associated with maintained expression of contractile smooth marker genes. In cultured intact mouse aorta, PTI-1 potentiated the DFMO-induced inhibition of cell proliferation. The combination of endogenous polyamine synthesis inhibition with uptake blockade is thus a viable approach for targeting unwanted vascular cell proliferation in vivo, including vascular restenosis.
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Affiliation(s)
- Mario Grossi
- Department of Experimental Medical Science, Lund University, Sweden
| | - Otto Phanstiel
- Department of Medical Education, University of Central Florida, Orlando, Florida
| | - Catarina Rippe
- Department of Experimental Medical Science, Lund University, Sweden
| | - Karl Swärd
- Department of Experimental Medical Science, Lund University, Sweden
| | - Azra Alajbegovic
- Department of Experimental Medical Science, Lund University, Sweden
| | | | - Amalia Forte
- Department of Experimental Medicine, Second University of Naples, Italy
| | - Lo Persson
- Department of Experimental Medical Science, Lund University, Sweden
| | - Per Hellstrand
- Department of Experimental Medical Science, Lund University, Sweden
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5
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Stegehake D, Kurosinski MA, Schürmann S, Daniel J, Lüersen K, Liebau E. Polyamine-independent Expression of Caenorhabditis elegans Antizyme. J Biol Chem 2015; 290:18090-18101. [PMID: 26032421 DOI: 10.1074/jbc.m115.644385] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Indexed: 11/06/2022] Open
Abstract
Degradation of ornithine decarboxylase, the rate-limiting enzyme of polyamine biosynthesis, is promoted by the protein antizyme. Expression of antizyme is positively regulated by rising polyamine concentrations that induce a +1 translational frameshift required for production of the full-length protein. Antizyme itself is negatively regulated by the antizyme inhibitor. In our study, the regulation of Caenorhabditis elegans antizyme was investigated, and the antizyme inhibitor was identified. By applying a novel GFP-based method to monitor antizyme frameshifting in vivo, we show that the induction of translational frameshifting also occurs under stressful conditions. Interestingly, during starvation, the initiation of frameshifting was independent of polyamine concentrations. Because frameshifting was also prevalent in a polyamine auxotroph double mutant, a polyamine-independent regulation of antizyme frameshifting is suggested. Polyamine-independent induction of antizyme expression was found to be negatively regulated by the peptide transporter PEPT-1, as well as the target of rapamycin, but not by the daf-2 insulin signaling pathway. Stress-dependent expression of C. elegans antizyme occurred morely slowly than expression in response to increased polyamine levels, pointing to a more general reaction to unfavorable conditions and a diversion away from proliferation and reproduction toward conservation of energy. Interestingly, antizyme expression was found to drastically increase in aging individuals in a postreproductive manner. Although knockdown of antizyme did not affect the lifespan of C. elegans, knockdown of the antizyme inhibitor led to a significant reduction in lifespan. This is most likely caused by an increase in antizyme-mediated degradation of ornithine decarboxylase-1 and a resulting reduction in cellular polyamine levels.
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Affiliation(s)
- Dirk Stegehake
- Department of Molecular Physiology, Institute for Animal Physiology, University of Muenster, 48143 Muenster, Germany
| | - Marc-André Kurosinski
- Department of Molecular Physiology, Institute for Animal Physiology, University of Muenster, 48143 Muenster, Germany
| | - Sabine Schürmann
- Department of Molecular Physiology, Institute for Animal Physiology, University of Muenster, 48143 Muenster, Germany
| | - Jens Daniel
- Department of Molecular Physiology, Institute for Animal Physiology, University of Muenster, 48143 Muenster, Germany
| | - Kai Lüersen
- Department of Molecular Physiology, Institute for Animal Physiology, University of Muenster, 48143 Muenster, Germany
| | - Eva Liebau
- Department of Molecular Physiology, Institute for Animal Physiology, University of Muenster, 48143 Muenster, Germany.
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6
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Ramos-Molina B, Lambertos A, Lopez-Contreras AJ, Kasprzak JM, Czerwoniec A, Bujnicki JM, Cremades A, Peñafiel R. Structural and degradative aspects of ornithine decarboxylase antizyme inhibitor 2. FEBS Open Bio 2014; 4:510-21. [PMID: 24967154 PMCID: PMC4066113 DOI: 10.1016/j.fob.2014.05.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Revised: 05/23/2014] [Accepted: 05/27/2014] [Indexed: 01/11/2023] Open
Abstract
Ornithine decarboxylase (ODC) is the key enzyme in the polyamine biosynthetic pathway. ODC levels are controlled by polyamines through the induction of antizymes (AZs), small proteins that inhibit ODC and target it to proteasomal degradation without ubiquitination. Antizyme inhibitors (AZIN1 and AZIN2) are proteins homologous to ODC that bind to AZs and counteract their negative effect on ODC. Whereas ODC and AZIN1 are well-characterized proteins, little is known on the structure and stability of AZIN2, the lastly discovered member of this regulatory circuit. In this work we first analyzed structural aspects of AZIN2 by combining biochemical and computational approaches. We demonstrated that AZIN2, in contrast to ODC, does not form homodimers, although the predicted tertiary structure of the AZIN2 monomer was similar to that of ODC. Furthermore, we identified conserved residues in the antizyme-binding element, whose substitution drastically affected the capacity of AZIN2 to bind AZ1. On the other hand, we also found that AZIN2 is much more labile than ODC, but it is highly stabilized by its binding to AZs. Interestingly, the administration of the proteasome inhibitor MG132 caused differential effects on the three AZ-binding proteins, having no effect on ODC, preventing the degradation of AZIN1, but unexpectedly increasing the degradation of AZIN2. Inhibitors of the lysosomal function partially prevented the effect of MG132 on AZIN2. These results suggest that the degradation of AZIN2 could be also mediated by an alternative route to that of proteasome. These findings provide new relevant information on this unique regulatory mechanism of polyamine metabolism.
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Key Words
- AZ, antizyme
- AZBE, antizyme-binding element
- AZIN, antizyme inhibitor
- Antizyme
- Antizyme-binding element
- ERGIC, endoplasmic reticulum-Golgi intermediate compartment
- GDT_TS, global distance test total score
- HA, hemagglutinin
- HEK, human embryonic kidney
- Homology modeling
- ODC, ornithine decarboxylase
- PAGE, polyacrylamide gel electrophoresis
- Polyamines
- Proteasome inhibitors
- Protein degradation
- RMSD, root-mean-square deviation
- TGN, trans-Golgi network
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Affiliation(s)
- Bruno Ramos-Molina
- Department of Biochemistry and Molecular Biology B and Immunology, University of Murcia, Spain ; Instituto Murciano de Investigación Biosanitaria (IMIB), Murcia, Spain
| | - Ana Lambertos
- Department of Biochemistry and Molecular Biology B and Immunology, University of Murcia, Spain ; Instituto Murciano de Investigación Biosanitaria (IMIB), Murcia, Spain
| | | | - Joanna M Kasprzak
- Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznan, Poland
| | - Anna Czerwoniec
- Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznan, Poland
| | - Janusz M Bujnicki
- International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Asunción Cremades
- Department of Biochemistry and Molecular Biology B and Immunology, University of Murcia, Spain ; Instituto Murciano de Investigación Biosanitaria (IMIB), Murcia, Spain
| | - Rafael Peñafiel
- Department of Biochemistry and Molecular Biology B and Immunology, University of Murcia, Spain ; Instituto Murciano de Investigación Biosanitaria (IMIB), Murcia, Spain
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7
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Polyamines and cancer: implications for chemotherapy and chemoprevention. Expert Rev Mol Med 2013; 15:e3. [PMID: 23432971 DOI: 10.1017/erm.2013.3] [Citation(s) in RCA: 214] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Polyamines are small organic cations that are essential for normal cell growth and development in eukaryotes. Under normal physiological conditions, intracellular polyamine concentrations are tightly regulated through a dynamic network of biosynthetic and catabolic enzymes, and a poorly characterised transport system. This precise regulation ensures that the intracellular concentration of polyamines is maintained within strictly controlled limits. It has frequently been observed that the metabolism of, and the requirement for, polyamines in tumours is frequently dysregulated. Elevated levels of polyamines have been associated with breast, colon, lung, prostate and skin cancers, and altered levels of rate-limiting enzymes in both biosynthesis and catabolism have been observed. Based on these observations and the absolute requirement for polyamines in tumour growth, the polyamine pathway is a rational target for chemoprevention and chemotherapeutics. Here we describe the recent advances made in the polyamine field and focus on the roles of polyamines and polyamine metabolism in neoplasia through a discussion of the current animal models for the polyamine pathway, chemotherapeutic strategies that target the polyamine pathway, chemotherapeutic clinical trials for polyamine pathway-specific drugs and ongoing clinical trials targeting polyamine biosynthesis.
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8
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Zhu Q, Jin L, Casero RA, Davidson NE, Huang Y. Role of ornithine decarboxylase in regulation of estrogen receptor alpha expression and growth in human breast cancer cells. Breast Cancer Res Treat 2012; 136:57-66. [PMID: 22976807 PMCID: PMC3715085 DOI: 10.1007/s10549-012-2235-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Accepted: 08/25/2012] [Indexed: 12/30/2022]
Abstract
Our previous studies demonstrated that specific polyamine analogues, oligoamines, down-regulated the activity of a key polyamine biosynthesis enzyme, ornithine decarboxylase (ODC), and suppressed expression of estrogen receptor alpha (ERα) in human breast cancer cells. However, the mechanism underlying the potential regulation of ERα expression by polyamine metabolism has not been explored. Here, we demonstrated that RNAi-mediated knockdown of ODC (ODC KD) down-regulated the polyamine pool, and hindered growth in ERα-positive MCF7 and T47D and ERα-negative MDA-MB-231 breast cancer cells. ODC KD significantly induced the expression and activity of the key polyamine catabolism enzymes, spermine oxidase (SMO) and spermidine/spermine N (1)-acetyltransferase (SSAT). However, ODC KD-induced growth inhibition could not be reversed by exogenous spermidine or overexpression of antizyme inhibitor (AZI), suggesting that regulation of ODC on cell proliferation may involve the signaling pathways independent of polyamine metabolism. In MCF7 and T47D cells, ODC KD, but not DFMO treatment, diminished the mRNA and protein expression of ERα. Overexpression of antizyme (AZ), an ODC inhibitory protein, suppressed ERα expression, suggesting that ODC plays an important role in regulation of ERα expression. Decrease of ERα expression by ODC siRNA altered the mRNA expression of a subset of ERα response genes. Our previous analysis showed that oligoamines disrupt the binding of Sp1 family members to an ERα minimal promoter element containing GC/CA-rich boxes. By using DNA affinity precipitation and mass spectrometry analysis, we identified ZBTB7A, MeCP2, PARP-1, AP2, and MAZ as co-factors of Sp1 family members that are associated with the ERα minimal promoter element. Taken together, these data provide insight into a novel antiestrogenic mechanism for polyamine biosynthesis enzymes in breast cancer.
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Affiliation(s)
- Qingsong Zhu
- The Sidney Kimmel Comprehensive Cancer Center, Johns, Hopkins University, Baltimore, MD, USA
| | - Lihua Jin
- The Sidney Kimmel Comprehensive Cancer Center, Johns, Hopkins University, Baltimore, MD, USA
| | - Robert A. Casero
- The Sidney Kimmel Comprehensive Cancer Center, Johns, Hopkins University, Baltimore, MD, USA
| | - Nancy E. Davidson
- Department of Pharmacology & Chemical Biology, University, of Pittsburgh, Pittsburgh, PA, USA
- University of Pittsburgh Cancer Institute, 5150 Centre Avenue, Suite 500, Pittsburgh, PA 15213, USA,
| | - Yi Huang
- Department of Pharmacology & Chemical Biology, University, of Pittsburgh, Pittsburgh, PA, USA
- University of Pittsburgh Cancer Institute, 5150 Centre Avenue, Suite 500, Pittsburgh, PA 15213, USA,
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9
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Kjellström J, Oredsson SM, Wennerberg J. Increased toxicity of a trinuclear Pt-compound in a human squamous carcinoma cell line by polyamine depletion. Cancer Cell Int 2012; 12:20. [PMID: 22640800 PMCID: PMC3487936 DOI: 10.1186/1475-2867-12-20] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Accepted: 05/28/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Mononuclear platinum anticancer agents hold a pivotal place in the treatment of many forms of cancers, however, there is a potential to improve response to evade resistance development and toxic side effects. BBR3464 is a promising trinuclear platinum anticancer agent, which is a polyamine mimic. The aim was to investigate the influence of polyamine pool reduction on the cytotoxic effects of the trinuclear platinum complex BBR3464 and cisplatin. Polyamine pool reduction was achieved by treating cells with either the polyamine biosynthesis inhibitor α-difluoromethylornithine (DFMO) or the polyamine analogue N1,N11-diethylnorspermine (DENSPM). METHODS A human squamous cell carcinoma cell line, LU-HNSCC-4, established from a primary head and neck tumour was used to evaluate cellular effects of each drug alone or combinations thereof. High-performance liquid-chromatography was used to quantify intracellular polyamine contents. Inductively coupled mass spectroscopy was used to quantify intracellular platinum uptake. Cells were exposed to DFMO or DENSPM during 48 h at concentrations ranging from 0 to 5 mM or 0 to 10 μM, respectively. Thereafter, non-treated and treated cells were exposed to cisplatin or BBR3464 during 1 h at concentrations ranging from 0 to 100 μM. A 96-well assay was used to determine cytotoxicity after five days after treatment. RESULTS The cytotoxic effect of BBR3464 on LU-HNSCC-4 cells was increased after cells were pre-treated with DENSPM or DFMO, and the interaction was found to be synergistic. In contrast, the interaction between cisplatin and DFMO or DENSPM was near-additive to antagonistic. The intracellular levels of the polyamines putrescine and spermidine were decreased after treatment with DFMO, and treatment with DENSPM resulted in an increase in putrescine level and concomitant decrease in spermidine and spermine levels. The uptake of BBR3464 was significantly increased after pre-treatment of the cells with DFMO, and varied dependent on the concentration of DENSPM. The uptake of cisplatin was unchanged. CONCLUSIONS Taken together, these results demonstrate that combinations of polyamine synthesis inhibitors with BBR3464 appear to be a promising approach to enhance the anticancer activity against HSCC.
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Affiliation(s)
- Johan Kjellström
- Department of Otorhinolaryngology/Head and Neck Surgery, University Hospital, S-221 85, Lund, Sweden.
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10
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Fraser AV, Goodwin AC, Hacker-Prietz A, Sugar E, Woster PM, Casero RA. Knockdown of ornithine decarboxylase antizyme 1 causes loss of uptake regulation leading to increased N1, N11-bis(ethyl)norspermine (BENSpm) accumulation and toxicity in NCI H157 lung cancer cells. Amino Acids 2011; 42:529-38. [PMID: 21814790 DOI: 10.1007/s00726-011-1030-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Accepted: 03/26/2011] [Indexed: 10/17/2022]
Abstract
Ornithine decarboxylase antizyme 1 (AZ1) is a major regulatory protein responsible for the regulation and degradation of ornithine decarboxylase (ODC). To better understand the role of AZ1 in polyamine metabolism and in modulating the response to anticancer polyamine analogues, a small interfering RNA strategy was used to create a series of stable clones in human H157 non-small cell lung cancer cells that expressed less than 5-10% of basal AZ1 levels. Antizyme 1 knockdown clones accumulated greater amounts of the polyamine analogue N (1),N (11)-bis(ethyl)norspermine (BENSpm) and were more sensitive to analogue treatment. The possibility of a loss of polyamine uptake regulation in the knockdown clones was confirmed by polyamine uptake analysis. These results are consistent with the hypothesis that AZ1 knockdown leads to dysregulation of polyamine uptake, resulting in increased analogue accumulation and toxicity. Importantly, there appears to be little difference between AZ1 knockdown cells and cells with normal levels of AZ1 with respect to ODC regulation, suggesting that another regulatory protein, potentially AZ2, compensates for the loss of AZ1. The results of these studies are important for the understanding of both the regulation of polyamine homeostasis and in understanding the factors that regulate tumor cell sensitivity to the anti-tumor polyamine analogues.
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Affiliation(s)
- Alison V Fraser
- Department of Oncology, The Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Bunting-Blaustein Cancer Research Building 1, 1650 Orleans Street, Baltimore, MD 21231, USA
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11
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Abstract
This chapter provides an overview of the polyamine field and introduces the 32 other chapters that make up this volume. These chapters provide a wide range of methods, advice, and background relevant to studies of the function of polyamines, the regulation of their content, their role in disease, and the therapeutic potential of drugs targeting polyamine content and function. The methodology provided in this new volume will enable laboratories already working in this area to expand their experimental techniques and facilitate the entry of additional workers into this rapidly expanding field.
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Affiliation(s)
- Anthony E Pegg
- College of Medicine, Milton S. Hershey Medical Center, Pennsylvania State University, Hershey, PA, USA
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12
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Boobis A, Watelet JB, Whomsley R, Benedetti MS, Demoly P, Tipton K. Drug interactions. Drug Metab Rev 2009; 41:486-527. [PMID: 19601724 DOI: 10.1080/10837450902891550] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Drugs for allergy are often taken in combination with other drugs, either to treat allergy or other conditions. In common with many pharmaceuticals, most such drugs are subject to metabolism by P450 enzymes and to transmembrane transport. This gives rise to considerable potential for drug-drug interactions, to which must be added consideration of drug-diet interactions. The potential for metabolism-based drug interactions is increasingly being taken into account during drug development, using a variety of in silico and in vitro approaches. Prediction of transporter-based interactions is not as advanced. The clinical importance of a drug interaction will depend upon a number of factors, and it is important to address concerns quantitatively, taking into account the therapeutic index of the compound.
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Affiliation(s)
- Alan Boobis
- Department of Experimental Medicine and Toxicology, Division of Medicine, Imperial College London, Hammersmith Campus, London.
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13
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Abstract
In addition to polyamine homoeostasis, it has become increasingly clear that polyamine catabolism can play a dominant role in drug response, apoptosis and the response to stressful stimuli, and contribute to the aetiology of several pathological states, including cancer. The highly inducible enzymes SSAT (spermidine/spermine N1-acetyltransferase) and SMO (spermine oxidase) and the generally constitutively expressed APAO (N1-acetylpolyamine oxidase) appear to play critical roles in many normal and disease processes. The dysregulation of polyamine catabolism frequently accompanies several disease states and suggests that such dysregulation may both provide useful insight into disease mechanism and provide unique druggable targets that can be exploited for therapeutic benefit. Each of these enzymes has the potential to alter polyamine homoeostasis in response to multiple cell signals and the two oxidases produce the reactive oxygen species H2O2 and aldehydes, each with the potential to produce pathological states. The activity of SSAT provides substrates for APAO or substrates for the polyamine exporter, thus reducing the intracellular polyamine concentration, the net effect of which depends on the magnitude and rate of any increase in SSAT. SSAT may also influence cellular metabolism via interaction with other proteins and by perturbing the content of acetyl-CoA and ATP. The goal of the present review is to cover those aspects of polyamine catabolism that have an impact on disease aetiology or treatment and to provide a solid background in this ever more exciting aspect of polyamine biology.
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Affiliation(s)
- Robert A Casero
- 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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14
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Stanic' I, Facchini A, Borzì RM, Stefanelli C, Flamigni F. The polyamine analogueN1,N11-diethylnorspermine can induce chondrocyte apoptosis independently of its ability to alter metabolism and levels of natural polyamines. J Cell Physiol 2009; 219:109-16. [DOI: 10.1002/jcp.21655] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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15
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Svensson KJ, Welch JE, Kucharzewska P, Bengtson P, Bjurberg M, Påhlman S, Ten Dam GB, Persson L, Belting M. Hypoxia-Mediated Induction of the Polyamine System Provides Opportunities for Tumor Growth Inhibition by Combined Targeting of Vascular Endothelial Growth Factor and Ornithine Decarboxylase. Cancer Res 2008; 68:9291-301. [DOI: 10.1158/0008-5472.can-08-2340] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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López-Contreras AJ, Ramos-Molina B, Cremades A, Peñafiel R. Antizyme inhibitor 2 (AZIN2/ODCp) stimulates polyamine uptake in mammalian cells. J Biol Chem 2008; 283:20761-9. [PMID: 18508777 PMCID: PMC3258956 DOI: 10.1074/jbc.m801024200] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Revised: 05/01/2008] [Indexed: 01/08/2023] Open
Abstract
One of the processes that regulate intracellular levels of polyamines in mammalian cells is polyamine uptake. We have measured polyamine uptake in COS7 cells for putrescine, spermidine, and spermine, obtaining K(m) values of 4.5, 1.0, and 0.8 mum, respectively. Treatment of nonconfluent cells with cycloheximide stimulated polyamine uptake and prevented the inhibitory effect found in cells preloaded with polyamines, suggesting the existence of a feedback repression mechanism mediated by antizymes. Transient transfected cells with mutated antizyme forms of AZ1, AZ2, and AZ3, which do not require frameshifting, showed a total blockade of polyamine uptake. Transfection of COS7 cells with mouse or human AZIN2, a novel member of the antizyme inhibitor family, recently characterized by our group, markedly stimulated polyamine uptake and counteracted the action of any of the three antizymes in co-transfected cells. The stimulatory effect of AZIN2 on polyamine uptake was abrogated when the putative antizyme binding sequence, formed by residues 117-140 in AZIN2, was deleted. Real time reverse transcription-PCR analysis of antizyme inhibitor transcripts revealed that in brain and testes AZIN2 is more expressed than AZIN1, especially in the testes where the relative expression was about 25-fold higher. Collectively, our results clearly indicate that AZIN2 affects polyamine homeostasis not only by increasing ornithine decarboxylase activity but also by stimulating polyamine uptake, through negating the inhibitory effect of the antizymes. This finding may have physiological relevance, mostly in testes where AZ3 and AZIN2 are mainly expressed.
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Affiliation(s)
- Andrés J. López-Contreras
- Department of Biochemistry and Molecular
Biology B and Immunology and Department of
Pharmacology, Faculty of Medicine, University of Murcia, 30100 Murcia,
Spain
| | - Bruno Ramos-Molina
- Department of Biochemistry and Molecular
Biology B and Immunology and Department of
Pharmacology, Faculty of Medicine, University of Murcia, 30100 Murcia,
Spain
| | - Asunción Cremades
- Department of Biochemistry and Molecular
Biology B and Immunology and Department of
Pharmacology, Faculty of Medicine, University of Murcia, 30100 Murcia,
Spain
| | - Rafael Peñafiel
- Department of Biochemistry and Molecular
Biology B and Immunology and Department of
Pharmacology, Faculty of Medicine, University of Murcia, 30100 Murcia,
Spain
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17
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Carew JS, Nawrocki ST, Reddy VK, Bush D, Rehg JE, Goodwin A, Houghton JA, Casero RA, Marton LJ, Cleveland JL. The novel polyamine analogue CGC-11093 enhances the antimyeloma activity of bortezomib. Cancer Res 2008; 68:4783-90. [PMID: 18559525 PMCID: PMC2749595 DOI: 10.1158/0008-5472.can-07-6483] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Multiple myeloma (MM) is an incurable plasma cell malignancy. The recent successes of the proteasome inhibitor bortezomib in MM therapy have prompted investigations of its efficacy in combination with other anticancer agents. Polyamines play important roles in regulating tumor cell proliferation and angiogenesis and represent an important therapeutic target. CGC-11093 is a novel polyamine analogue that has completed a phase I clinical trial for the treatment of cancer. Here, we report that CGC-11093 selectively augments the in vitro and in vivo antimyeloma activity of bortezomib. Specifically, the combination of CGC-11093 and bortezomib compromised MM viability and clonogenic survival, and increased drug-induced apoptosis over that achieved by either single agent. Xenografts of MM tumors treated with this combination had marked increases in phospho-c-Jun-NH(2)-kinase (JNK)-positive cells and apoptosis, and corresponding reductions in tumor burden, tumor vasculature, and the expression of proliferating cell nuclear antigen and the proangiogenic cytokine vascular endothelial growth factor. Furthermore, inhibition of JNK with a pharmacologic inhibitor or by selective knockdown blunted the efficacy of CGC-11093 and bortezomib. Therefore, CGC-11093 enhances the anticancer activity of bortezomib by augmenting JNK-mediated apoptosis and blocking angiogenesis. These findings support the study of the use of the combination of bortezomib and CGC-11093 in MM patients that fail to respond to frontline therapy.
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Affiliation(s)
- Jennifer S. Carew
- Department of Biochemistry, St. Jude Children's Research Hospital, Memphis, Tennessee
- The CTRC Institute for Drug Development, San Antonio, Texas
| | - Steffan T. Nawrocki
- Department of Oncology, and St. Jude Children's Research Hospital, Memphis, Tennessee
- The CTRC Institute for Drug Development, San Antonio, Texas
| | | | - Dorothy Bush
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Jerold E. Rehg
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Andrew Goodwin
- Department of Oncology, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Janet A. Houghton
- Department of Oncology, and St. Jude Children's Research Hospital, Memphis, Tennessee
- The Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Robert A. Casero
- Department of Oncology, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | | | - John L. Cleveland
- Department of Biochemistry, St. Jude Children's Research Hospital, Memphis, Tennessee
- Department of Cancer Biology, The Scripps Research Institute, Jupiter, Florida
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18
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In vitro and in vivo effects of the conformationally restricted polyamine analogue CGC-11047 on small cell and non-small cell lung cancer cells. Cancer Chemother Pharmacol 2008; 63:45-53. [PMID: 18301893 DOI: 10.1007/s00280-008-0706-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2007] [Accepted: 02/11/2008] [Indexed: 10/22/2022]
Abstract
PURPOSE Polyamines are essential for normal growth; however, the requirement for, and the metabolism of, polyamines are frequently dysregulated in cancer. Polyamine analogues have demonstrated promising preclinical results in multiple model systems of cancer, but their clinical utility has been limited by apparent toxicity. A representative compound of a new generation of short chain, conformationally restricted polyamine analogues, CGC-11047 has been synthesized and ongoing phase I clinical trials indicate it to be well tolerated at weekly doses of 610 mg (dose escalation is still in progress). Therefore, studies were designed to gain a better understanding of its effects on cellular polyamine biochemistry and efficacy in the treatment of human lung cancer models in vitro and in vivo. METHODS Human lung cancers cell lines representing non-small cell and small cell lung cancers were investigated for their growth and biochemical response to CGC-11047. Effects of in vitro treatment with CGC-11047 on cell growth, the activity of the polyamine biosynthetic enzyme ornithine decarboxylase (ODC), and the expression and activity of the polyamine catabolic enzymes spermidine/spermine N(1)-acetyltransferase (SSAT) and spermine oxides (SMO) were measured. Additionally, the overall effects on intracellular polyamine pools were monitored. Finally, the in vivo efficacy of CGC-11047 in the treatment of a nude mouse model of human non-small cell lung cancer was evaluated. RESULTS CGC-11047 effectively inhibited the growth of both small cell and non-small cell lung cancer cells in vitro. The greatest biochemical effects were observed in the non-small cell lung cancer cells where in addition to a profound down regulation of ODC activity, there was a significant increase in polyamine catabolism leading to a greater degree of polyamine pool depletion and greater accumulation of CGC-11047 when compared with the changes observed for the small cell lines. Importantly, CGC-11047 was found to be highly significant (P < 0.0001) in delaying the progression of established tumors in an in vivo model of human non-small cell lung cancer. CONCLUSION CGC-11047 represents a promising new polyamine analogue that warrants further preclinical and, potentially, clinical evaluation in lung cancer.
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19
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Mitchell JLA, Thane TK, Sequeira JM, Thokala R. Unusual aspects of the polyamine transport system affect the design of strategies for use of polyamine analogues in chemotherapy. Biochem Soc Trans 2007; 35:318-21. [PMID: 17371269 DOI: 10.1042/bst0350318] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
One strategy for inhibiting tumour cell growth is the use of polyamine mimetics to depress endogenous polyamine levels and, ideally, obstruct critical polyamine-requiring reactions. Such polyamine analogues make very unusual drugs, in that extremely high intracellular concentrations are required for growth inhibition or cytotoxicity. Cells exposed to even sub-micromolar concentrations of such analogues can achieve effective intracellular levels because these compounds are incorporated by the very aggressive polyamine uptake system. Once incorporated to these levels, many of these analogues induce the synthesis of a regulatory protein, antizyme, which inhibits both polyamine synthesis and the transporter they used to enter the cell. Thus this feedback system allows steady-state maintenance of effective cellular doses of such analogues. Accordingly, effective cellular levels of polyamine analogues are generally inversely related to their capacity to induce antizyme. Antizyme activity is down-regulated by interaction with several binding partners, most notably antizyme inhibitor, and at least a few tumour tissues exhibit deficiencies in antizyme expression. Our studies explore the role of antizyme induction by several polyamine analogues in their physiological response and the possibility that cell-to-cell differences in antizyme expression may contribute to variable sensitivities to these agents.
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20
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Phanstiel O, Kaur N, Delcros JG. Structure-activity investigations of polyamine-anthracene conjugates and their uptake via the polyamine transporter. Amino Acids 2007; 33:305-13. [PMID: 17410331 DOI: 10.1007/s00726-007-0527-y] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2006] [Accepted: 02/01/2007] [Indexed: 10/23/2022]
Abstract
A series of polyamine conjugates were synthesized and evaluated for their ability to target the polyamine transporter (PAT) in two Chinese hamster ovary (CHO) cell lines (PAT-active CHO and PAT-inactive CHOMG). This systematic study identified salient features of the polyamine architecture required to target and enter cells via the PAT. Indeed, the separation of charges, the degree of N-alkylation, and the spacer unit connecting the N(1)-terminus to the appended cytotoxic component (anthracene) were found to be key contributors to optimal delivery via the PAT. Using the CHO screen, the homospermidine motif (e.g., 4,4-triamine) was identified as a polyamine vector, which could enable the selective import of large N(1)-substituents (i.e., naphthylmethyl, anthracenylmethyl and pyrenylmethyl), which were cytotoxic to cells. The cell selectivity of this approach was demonstrated in B-16 murine melanoma cells and normal melanocytes (Mel-A). Three polyamine areas (recognition and transport, vesicle sequestration and polyamine-target interactions) were identified for future research.
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Affiliation(s)
- O Phanstiel
- Department of Chemistry, University of Central Florida, Orlando, FL 32816-2366, USA.
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21
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Mitchell JLA, Thane TK, Sequeira JM, Marton LJ, Thokala R. Antizyme and antizyme inhibitor activities influence cellular responses to polyamine analogs. Amino Acids 2007; 33:291-7. [PMID: 17410332 DOI: 10.1007/s00726-007-0523-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2006] [Accepted: 02/01/2007] [Indexed: 02/01/2023]
Abstract
Close structural analogs of spermidine and spermine, polyamine mimetics, are potential chemotheraputic agents as they depress cellular polyamines required for tumor growth. Specific mimetic analogs stimulate synthesis of the regulatory protein antizyme (AZ), which not only inactivates the initial enzyme in polyamine biosynthesis but also inhibits cellular uptake of polyamines. The role of AZ induction in influencing cellular uptake of representative analogs was investigated using three analogs produced by Cellgate Inc., CGC-11047, CGC-11102, and CGC-11144, which exhibit markedly distinct AZ-inducing potential. An inverse correlation was noted between the AZ-inducing activity of a compound and the steady-state levels accumulated in cells. As some tumor cells over express AZI as a means of enhancing the polyamines required for aggressive growth, analog sensitivity was examined in transgenic CHO cells expressing exogenous antizyme inhibitor protein (AZI). Although AZI over expression increased cell sensitivity to analogs, the degree of this affect varied with the analog used.
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Affiliation(s)
- J L A Mitchell
- Department of Biological Sciences, Northern Illinois University, DeKalb, IL 60115-2861, USA.
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22
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Petros LM, Graminski GF, Robinson S, Burns MR, Kisiel N, Gesteland RF, Atkins JF, Kramer DL, Howard MT, Weeks RS. Polyamine Analogs with Xylene Rings Induce Antizyme Frameshifting, Reduce ODC Activity, and Deplete Cellular Polyamines. ACTA ACUST UNITED AC 2006; 140:657-66. [PMID: 16998202 DOI: 10.1093/jb/mvj193] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Numerous studies have correlated elevated polyamine levels with abnormal or rapid cell growth. One therapeutic strategy to treat diseases with increased cellular proliferation rates, most obviously cancer, has been to identify compounds which lower cellular polyamine levels. An ideal target for this strategy is the protein antizyme-a negative regulator of polyamine biosynthesis and import, and a positive regulator of polyamine export. In this study, we have optimized two tissue-culture assays in 96-well format, to allow the rapid screening of a 750-member polyamine analog library for compounds which induce antizyme frameshifting and fail to substitute for the natural polyamines in growth. Five analogs (MQTPA1-5) containing xylene (1,4-dimethyl benzene) were found to be equal to or better than spermidine at stimulating antizyme frameshifting and were inefficient at rescuing cell growth following polyamine depletion. These compounds were further characterized for effects on natural polyamine levels and enzymes involved in polyamine metabolism. Finally, direct measurements of antizyme induction in cells treated with two of the lead compounds revealed an 8- to 15-fold increase in antizyme protein over untreated cells. The impact of the xylene moiety and the distance between the positively charged amino groups on antizyme frameshifting and cell growth are discussed.
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Affiliation(s)
- Lorin M Petros
- Department of Human Genetics, University of Utah, 15 N 2030 E, Rm 7410, Salt Lake City, UT 84112-5330, USA.
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23
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Kim SW, Mangold U, Waghorne C, Mobascher A, Shantz L, Banyard J, Zetter BR. Regulation of cell proliferation by the antizyme inhibitor: evidence for an antizyme-independent mechanism. J Cell Sci 2006; 119:2583-91. [PMID: 16735445 DOI: 10.1242/jcs.02966] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The antizyme inhibitor was discovered as a protein that binds to the regulatory protein antizyme and inhibits the ability of antizyme to interact with the enzyme ornithine decarboxylase (ODC). Blocking antizyme activity subsequently leads to increased intracellular levels of ODC and increased ODC enzymatic activity. We now report that antizyme inhibitor is a positive modulator of cell growth. Overexpression of antizyme inhibitor in NIH-3T3 mouse fibroblasts or in AT2.1 Dunning rat prostate carcinoma cells resulted in an increased rate of cell proliferation and an increase in saturation density of the cultured cells. This was accompanied by an increase in intracellular levels of the polyamine putrescine. In AT2.1 cells, antizyme inhibitor overexpression also increased the ability of the cells to form foci when grown under anchorage-independent conditions. In order to determine the role of antizyme on antizyme inhibitor activity we created an antizyme inhibitor mutant, AZI(Delta117-140), which lacks the putative antizyme-binding domain. We show that this mutant fails to bind to antizyme, but remains capable of inducing increased rates of cell proliferation, suggesting that antizyme inhibitor has antizyme-independent functions. Silencing antizyme inhibitor expression leads to diminished levels of cyclin D1 and to reduced cell proliferation. Antizyme inhibitor is capable of preventing cyclin D1 degradation, and this effect is at least partially independent of antizyme. We show that wild-type antizyme inhibitor and the AZI(DeltaY) mutant are capable of direct interaction with cyclin D1 suggesting a potential mechanism for the antizyme-independent effects. Together, our data suggest a novel function for antizyme inhibitor in cellular growth control.
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Affiliation(s)
- Sonia W Kim
- Program in Vascular Biology and Department of Surgery, Children's Hospital, Boston, MA 02115, USA
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24
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Rodríguez-Caso C, Montañez R, Cascante M, Sánchez-Jiménez F, Medina MA. Mathematical modeling of polyamine metabolism in mammals. J Biol Chem 2006; 281:21799-21812. [PMID: 16709566 DOI: 10.1074/jbc.m602756200] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Polyamines are considered as essential compounds in living cells, since they are involved in cell proliferation, transcription, and translation processes. Furthermore, polyamine homeostasis is necessary to cell survival, and its deregulation is involved in relevant processes, such as cancer and neurodegenerative disorders. Great efforts have been made to elucidate the nature of polyamine homeostasis, giving rise to relevant information concerning the behavior of the different components of polyamine metabolism, and a great amount of information has been generated. However, a complex regulation at transcriptional, translational, and metabolic levels as well as the strong relationship between polyamines and essential cell processes make it difficult to discriminate the role of polyamine regulation itself from the whole cell response when an experimental approach is given in vivo. To overcome this limitation, a bottom-up approach to model mathematically metabolic pathways could allow us to elucidate the systemic behavior from individual kinetic and molecular properties. In this paper, we propose a mathematical model of polyamine metabolism from kinetic constants and both metabolite and enzyme levels extracted from bibliographic sources. This model captures the tendencies observed in transgenic mice for the so-called key enzymes of polyamine metabolism, ornithine decarboxylase, S-adenosylmethionine decarboxylase and spermine spermidine N-acetyl transferase. Furthermore, the model shows a relevant role of S-adenosylmethionine and acetyl-CoA availability in polyamine homeostasis, which are not usually considered in systemic experimental studies.
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Affiliation(s)
- Carlos Rodríguez-Caso
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Universidad de Málaga, Málaga E-29071, Spain
| | - Raúl Montañez
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Universidad de Málaga, Málaga E-29071, Spain
| | - Marta Cascante
- Departamento de Bioquímica, Facultad de Química, Universidad de Barcelona, Barcelona E-08028, Spain
| | - Francisca Sánchez-Jiménez
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Universidad de Málaga, Málaga E-29071, Spain
| | - Miguel A Medina
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Universidad de Málaga, Málaga E-29071, Spain.
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25
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Romero-Calderón R, Krantz D. Transport of polyamines in Drosophila S2 cells: kinetics, pharmacology and dependence on the plasma membrane proton gradient. Biochem J 2006; 393:583-9. [PMID: 16248856 PMCID: PMC1360709 DOI: 10.1042/bj20050981] [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] [Indexed: 11/17/2022]
Abstract
Polyamine transport activities have been described in diverse multicellular systems, but their bioenergetic mechanisms and molecular identity remain unclear. In the present paper, we describe a high-affinity spermine/spermidine transport activity expressed in Drosophila S2 cells. Ion-replacement experiments indicate that polyamine uptake across the cell membrane is Na+-, K+-, Cl-- and Ca2+-independent, but pH-sensitive. Additional experiments using ionophores suggest that polyamine uptake may be H+-coupled. Pharmacological experiments show that polyamine uptake in S2 cells is selectively blocked by MGBG {methylglyoxal bis(guanylhydrazone) or 1,1'-[(methylethanediylidine)-dinitrilo]diguanidine} and paraquat (N,N-dimethyl-4,4'-bipyridylium), two known inhibitors of polyamine uptake in mammalian cells. In addition, inhibitors known to block the Slc22 (solute carrier 22) family of organic anion/cation transporters inhibit spermine uptake in S2 cells. These data and the genetic tools available in Drosophila will facilitate the molecular identification and further characterization of this activity.
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Affiliation(s)
| | - David E. Krantz
- †Department of Psychiatry and Biobehavioral Sciences, The David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, U.S.A
- To whom correspondence should be addressed (email )
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26
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Abstract
Ornithine decarboxylase (ODC) initiates the polyamine biosynthetic pathway. The amount of ODC is altered in response to many growth factors, oncogenes, and tumor promoters and to changes in polyamine levels. Susceptibility to tumor development is increased in transgenic mice expressing high levels of ODC and is decreased in mice with reduced ODC due to loss of one ODC allele or elevated expression of antizyme, a protein that stimulates ODC degradation. This review describes key factors that contribute to the regulation of ODC levels, which can occur at the levels of transcription, translation, and protein turnover.
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Affiliation(s)
- Anthony E Pegg
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA.
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27
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Abstract
The natural polyamines are aliphatic cations with multiple functions and are essential for cell growth. Soon after the critical requirement of polyamines for cell proliferation was recognized, the metabolism of polyamines was pursued as a target for antineoplastic therapy. Initially, much attention was focused on the development of inhibitors of polyamine biosynthesis as a means to inhibit tumor growth. The best-characterized inhibitor is alpha-difluoromethylornithine (DFMO), an irreversible inhibitor of ornithine decarboxylase. While compensatory mechanisms in polyamine metabolism reduce the effectiveness of DFMO as a single chemotherapeutic agent, it is currently undergoing extensive testing and clinical trials for chemoprevention and other diseases. There has been increasing interest over the last two decades in the cytotoxic response to agents that target the regulation of polyamine metabolism rather than directly inhibiting the metabolic enzymes in tumor cells. This interest resulted in the development of a number of polyamine analogs that exhibit effective cytotoxicity against tumor growth in preclinical models. The analogs enter cells through a selective polyamine transport system and can be either polyamine antimetabolites that deplete the intracellular polyamines or polyamine mimetics that displace the natural polyamines from binding sites, but do not substitute in terms of growth-promoting function. Synthesis of the first generation of symmetrically substituted bis(alkyl)polyamine analogs in the mid-1980s was based on the theory that polyamines may utilize feedback mechanisms to auto-regulate their synthesis. In the 1990s, unsymmetrically substituted bis(alkyl) polyamine analogs were developed. These compounds display structure-dependent and cell type-specific cellular effects and regulation on polyamine metabolism. More recently, a novel class of analogs has been synthesized, which include conformationally restricted, cyclic and long-chain oligoamine analogs. The development and use of these analogs have provided valuable information for understanding the molecular mechanisms of targeting the polyamine pathway as a means of cancer therapy.
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Affiliation(s)
- Yi Huang
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
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28
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Seiler N. Pharmacological aspects of cytotoxic polyamine analogs and derivatives for cancer therapy. Pharmacol Ther 2005; 107:99-119. [PMID: 15963353 DOI: 10.1016/j.pharmthera.2005.02.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/11/2005] [Indexed: 11/18/2022]
Abstract
During the past 20 years, numerous derivatives and analogues of spermidine (Spd) and spermine (Spm) were synthesized with the aim to generate a new type of anticancer drug. The common denominator of most cytotoxic polyamine analogues is their lipophilicity, which is superior to that of the parent amines. The natural polyamines bind to polyanions and to proteins with anionic binding sites. Their hydrophilicity/hydrophobicity is balanced, allowing them to perform physiological functions by interacting with some of these anionic structures, without impairing the functionality of others. Because the attachment of lipophilic substituents to the polyamine backbone increases the binding energy, lipophilic polyamine derivatives affect secondary and tertiary structures of a larger number of macromolecules than do their natural counterparts. In addition, lipophilicity improves the blood-brain barrier transport and thus enhances CNS toxicity. Close structural analogues of spermidine and spermine mimic the natural polyamines in regulatory functions. The cytotoxic mechanisms of analogues with a less close structural resemblance to spermidine or spermine have not been completely clarified. The displacement of spermidine from functional binding sites and the consequent prevention of its physiological roles is a likely mechanism, but many others may play a role as well. Up to now, polyamine analogues were conceived without specific growth-related targets in mind. To develop therapeutically useful drugs, it will be imperative to identify specific targets and to design compounds that interact selectively with the target molecules. It will also be necessary to include, at an early state of the work, pharmacological and toxicological considerations, to avoid unproductive directions.
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Affiliation(s)
- Nikolaus Seiler
- Laboratory of Nutritional Cancer Prevention, Institut de Recherche contre les Cancers de l'Appareil Digestif, Strasbourg Cedex 67091, France.
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