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Hypoxia-Directed Drug Strategies to Target the Tumor Microenvironment. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 772:111-45. [DOI: 10.1007/978-1-4614-5915-6_6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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52
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You BR, Shin HR, Park WH. PX-12 inhibits the growth of A549 lung cancer cells via G2/M phase arrest and ROS-dependent apoptosis. Int J Oncol 2013; 44:301-8. [PMID: 24172913 DOI: 10.3892/ijo.2013.2152] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 10/01/2013] [Indexed: 11/05/2022] Open
Abstract
PX-12 (1-methylpropyl 2-imidazolyl disulfide) is an inhibitor of thioredoxin (Trx-1), which has antitumor effects. However, little is known about the toxicological effect of PX-12 on cancer cells. We investigated the anti-growth effects of PX-12 on A549 lung cancer cells in relation to reactive oxygen species (ROS) and glutathione (GSH) levels. Based on MTT assays, PX-12 inhibited the growth of A549 cells with an IC50 of approximately 20 µM at 72 h. DNA flow cytometric analysis indicated that PX-12 significantly induced the G2/M phase arrest of the cell cycle in A549 cells. This agent also induced apoptotic cell death, as demonstrated by Annexin V-FITC staining cells and the loss of mitochondrial membrane potential MMP (∆ψm). In addition, the administration of Bax siRNA attenuated PX-12-induced A549 cell death. All the tested caspase inhibitors, especially Z-VAD significantly prevented apoptosis induced by PX-12. With respect to ROS and GSH levels, PX-12 increased ROS levels including O2(•)- in A549 cells and induced GSH depletion. N-acetyl cysteine (NAC) markedly reduced ROS levels in PX-12-treated A549 cells. NAC also prevented apoptotic cell death and GSH depletion induced by PX-12. This is the first report to show that PX-12 inhibits the growth of A549 cells via G2/M phase arrest, and Bax-mediated and ROS-dependent apoptosis.
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Affiliation(s)
- Bo Ra You
- Department of Physiology, Medical School, Research Institute for Endocrine Sciences, Chonbuk National University, Jeonju 561-180, Republic of Korea
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53
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Shin HR, You BR, Park WH. PX-12-induced HeLa cell death is associated with oxidative stress and GSH depletion. Oncol Lett 2013; 6:1804-1810. [PMID: 24260080 PMCID: PMC3833989 DOI: 10.3892/ol.2013.1637] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Accepted: 10/11/2013] [Indexed: 01/11/2023] Open
Abstract
PX-12, as an inhibitor of thioredoxin (Trx), has antitumor activity. However, little is known about the toxicological effect of PX-12 on cervical cancer cells. In the present study, the growth inhibitory effects of PX-12 on HeLa cervical cancer cells in association with reactive oxygen species (ROS) and glutathione (GSH) levels were investigated. Based on MTT assays, PX-12 inhibited the growth of HeLa cells with an IC50 value of ~7 μM at 72 h. DNA flow cytometry analysis indicated that 5 and 10 μM PX-12 significantly induced a G2/M phase arrest of the cell cycle. PX-12 also increased the number of dead cells and annexin V-fluorescein isothiocyanate-positive cells, which was accompanied by the loss of mitochondrial membrane potential. All the investigated caspase inhibitors significantly rescued certain cells from PX-12-induced HeLa cell death. With respect to ROS and GSH levels, PX-12 increased ROS levels (including O2•-) in HeLa cells and induced GSH depletion. N-acetyl cysteine markedly reduced the levels of O2•- in PX-12-treated HeLa cells, and prevented apoptotic cell death and GSH depletion in these cells. By contrast, L-buthionine sulfoximine intensified cell death and GSH depletion in PX-12-treated HeLa cells. To conclude, this is the first study to demonstrate that PX-12 inhibits the growth of HeLa cells via G2/M phase arrest, as well as inhibiting apoptosis; the effect was associated with intracellular increases in ROS levels and GSH depletion.
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Affiliation(s)
- Hye Rim Shin
- Department of Physiology, Medical School, Research Institute for Endocrine Sciences, Chonbuk National University, Jeonju 561-180, Republic of Korea
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54
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Abstract
Cysteine residues on proteins play key roles in catalysis and regulation. These functional cysteines serve as active sites for nucleophilic and redox catalysis, sites of allosteric regulation, and metal-binding ligands on proteins from diverse classes including proteases, kinases, metabolic enzymes, and transcription factors. In this review, we focus on a few select examples that serve to highlight the multiple functions performed by cysteines, with an emphasis on cysteine-mediated protein activities implicated in cancer. The enhanced reactivity of functional cysteines renders them susceptible to modification by electrophilic species. Toward this end, we discuss recent advancements and future prospects for utilizing cysteine-reactive small molecules as drugs and imaging agents for the treatment and diagnosis of cancer.
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Affiliation(s)
- Nicholas J. Pace
- Department of Chemistry, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Eranthie Weerapana
- Department of Chemistry, Boston College, Chestnut Hill, Massachusetts 02467, United States
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55
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DiRaimondo TR, Plugis NM, Jin X, Khosla C. Selective inhibition of extracellular thioredoxin by asymmetric disulfides. J Med Chem 2013; 56:1301-10. [PMID: 23327656 PMCID: PMC3574193 DOI: 10.1021/jm301775s] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Whereas the role of mammalian thioredoxin (Trx) as an intracellular protein cofactor is widely appreciated, its function in the extracellular environment is not well-understood. Only few extracellular targets of Trx-mediated thiol-disulfide exchange are known. For example, Trx activates extracellular transglutaminase 2 (TG2) via reduction of an intramolecular disulfide bond. Because hyperactive TG2 is thought to play a role in various diseases, understanding the biological role of extracellular Trx may provide critical insight into the pathogenesis of these disorders. Starting from a clinical-stage asymmetric disulfide lead, we have identified analogs with >100-fold specificity for Trx. Structure-activity relationship and computational docking model analyses have provided insights into the features important for enhancing potency and specificity. The most active compound identified had an IC(50) below 0.1 μM in cell culture and may be appropriate for in vivo use to interrogate the role of extracellular Trx in health and disease.
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Affiliation(s)
| | | | - Xi Jin
- Department of Chemistry, Stanford University, Stanford CA 94305
| | - Chaitan Khosla
- Department of Chemical Engineering, Stanford University, Stanford CA 94305
- Department of Chemistry, Stanford University, Stanford CA 94305
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Development of hypoxia-inducible factor (HIF)-1α inhibitors: Effect of ortho-carborane substituents on HIF transcriptional activity under hypoxia. Bioorg Med Chem Lett 2013; 23:806-10. [DOI: 10.1016/j.bmcl.2012.11.081] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Revised: 11/19/2012] [Accepted: 11/20/2012] [Indexed: 02/08/2023]
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57
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Nyström T, Yang J, Molin M. Peroxiredoxins, gerontogenes linking aging to genome instability and cancer. Genes Dev 2012; 26:2001-8. [PMID: 22987634 DOI: 10.1101/gad.200006.112] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Age is the highest risk factor known for a large number of maladies, including cancers. However, it is unclear how aging mechanistically predisposes the organism to such diseases and which gene products are the primary targets of the aging process. Recent studies suggest that peroxiredoxins, antioxidant enzymes preventing tumor development, are targets of age-related deterioration and that bolstering their activity (e.g., by caloric restriction) extends cellular life span. This review focuses on how the peroxiredoxin functions (i.e., as peroxidases, signal transducers, and molecular chaperones) fit with contemporary theories of aging and whether peroxiredoxins could be targeted therapeutically in the treatment of age-associated cancers.
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Affiliation(s)
- Thomas Nyström
- Department of Cell and Molecular Biology, University of Gothenburg, Göteborg, Sweden.
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58
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Derijks-Engwegen JY, Cats A, Smits ME, Schellens JH, Beijnen JH. Improving colorectal cancer management: the potential of proteomics. Biomark Med 2012; 2:253-89. [PMID: 20477414 DOI: 10.2217/17520363.2.3.253] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Colorectal cancer (CRC) is the third most common cancer worldwide. Successful treatment is heavily dependent on tumor stage at the time of detection, but unfortunately CRC is often only detected in advanced stages. New biomarkers in the form of genes or proteins that can be used for diagnosis, prognostication, follow-up, and treatment selection and monitoring could be of great benefit for the management of CRC. Furthermore, proteins could prove valuable new targets for therapy. Therefore, clinical proteomics has gained a lot of scientific interest in this regard. To get an overall insight into the extent to which this research has contributed to a better management of CRC, we give a comprehensive overview of the results of proteomics research on CRC, focusing on expression proteomics, in other words, protein profiling studies. Furthermore, we evaluate the potential of the discriminating proteins identified in this research for clinical use as biomarkers for (early) diagnosis, prognosis and follow-up of CRC or as targets for new therapeutic regimens.
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59
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Nagano M, Hatakeyama K, Kai M, Nakamura H, Yodoi J, Asada Y, Chijiiwa K. Nuclear expression of thioredoxin-1 in the invasion front is associated with outcome in patients with gallbladder carcinoma. HPB (Oxford) 2012; 14:573-82. [PMID: 22882193 PMCID: PMC3461382 DOI: 10.1111/j.1477-2574.2012.00482.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Multifunctional redox protein human thioredoxin (TRX-1) is reduced by thioredoxin reductase (TRX-R). The aim of the present study was to examine the distribution of TRX-1 and TRX-R expressions in gallbladder carcinoma (GBC) to clarify their usefulness as prognostic factors after surgical resection. METHODS Immunohistochemical staining for TRX-1 and TRX-R was performed in GBC tissue from 38 patients who underwent surgical resection, and TRX-1/TRX-R localization in relation to outcome was examined. RESULTS TRX-1 protein levels were significantly higher in GBC samples than in cholecystolithiasis samples (P = 0.0174). TRX-1 expression was observed in 100% (38/38) of tumour samples and in the nucleus in 76% (29/38), with nuclear expression in the invasion front observed in 45% (13/29). TRX-R expression was only detected in the cytoplasm of cancer cells and in the invasion front in 28 samples. In all of the samples, the depth of tumour invasion, lymph node metastasis, surgical margin, curability and nuclear expression of TRX-1 in the invasion front were significant prognostic factors by univariate analysis. In 27 selected patients who underwent curative resection, both TRX-1 nuclear expression and TRX-R cytoplasmic expression in the invasion front was a significantly prognostic factor. CONCLUSION TRX-1 nuclear expression in the GBC invasion front is a significant prognostic marker. Patients with both TRX-1 nuclear expression and TRX-R cytoplasmic expression in the tumour invasion front should be observed carefully even if after curative resection.
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Affiliation(s)
- Motoaki Nagano
- Department of Surgical Oncology and Regulation of Organ FunctionMiyazaki
| | - Kinta Hatakeyama
- Department of First Pathology, Miyazaki University School of MedicineMiyazaki
| | - Masahiro Kai
- Department of Surgical Oncology and Regulation of Organ FunctionMiyazaki
| | - Hajime Nakamura
- Department of Biological Responses, Institute for Virus Research, Kyoto UniversityKyoto, Japan
| | - Junji Yodoi
- Department of Biological Responses, Institute for Virus Research, Kyoto UniversityKyoto, Japan
| | - Yujiro Asada
- Department of First Pathology, Miyazaki University School of MedicineMiyazaki
| | - Kazuo Chijiiwa
- Department of Surgical Oncology and Regulation of Organ FunctionMiyazaki
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60
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Baker AF, Adab KN, Raghunand N, Chow H, Stratton SP, Squire SW, Boice M, Pestano LA, Kirkpatrick DL, Dragovich T. A phase IB trial of 24-hour intravenous PX-12, a thioredoxin-1 inhibitor, in patients with advanced gastrointestinal cancers. Invest New Drugs 2012; 31:631-641. [PMID: 22711542 DOI: 10.1007/s10637-012-9846-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Accepted: 05/31/2012] [Indexed: 11/25/2022]
Abstract
We investigated the safety, pharmacokinetics, and pharmacodynamics of PX-12, a thioredoxin-1 (Trx-1) inhibitor, administered as a 24-hour infusion every 7 or 14 days in patients with gastrointestinal malignancies. PX-12 is the first Trx-1 inhibitor to undergo clinical development. The first Phase 1 study of PX-12 demonstrated promising clinical activity, but the 1 and 3 hour-infusion schedules investigated were associated with a strong and irritating odor due to exhalation of one of its metabolites, 2-butanethiol. In an effort to achieve tolerability and achieve a drug exposure level necessary for biological activity, the current study was undertaken. While the maximally tolerated dose was estimated to be 300 mg/m(2) /24 h once a week as the 2-butanethiol expirate was tolerable at that dose level, no evidence of clinical activity was observed. Pharmacokinetic studies of the parent compound PX-12 demonstrated rapid, irreversible binding to plasma components, resulting in low (ng/ml) peak plasma concentrations of non-bound PX-12 during infusion. DCE-MRI was performed pre-and post-infusion in three patients. There were no significant trends observed in changes in plasma Trx-1, vascular endothelial growth factor (VEGF), or beta fibroblast growth factor (FGF-2) pre- or post-treatment. However, there was a trend for a decrease in circulating Trx-1 during the first four PX-12 treatment cycles in patients that had a Trx-1 baseline level >18 ng/mL. Aggregate clinical trial results suggest that further clinical development of PX-12, as an intravenous infusion, is not feasible. However, the Trx-1 pathway remains a target of interest in patients with gastrointestinal malignancies.
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Leal SM, Vareechon C, Cowden S, Cobb BA, Latgé JP, Momany M, Pearlman E. Fungal antioxidant pathways promote survival against neutrophils during infection. J Clin Invest 2012; 122:2482-98. [PMID: 22706306 DOI: 10.1172/jci63239] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Accepted: 05/09/2012] [Indexed: 01/15/2023] Open
Abstract
Filamentous fungi are a common cause of blindness and visual impairment worldwide. Using both murine model systems and in vitro human neutrophils, we found that NADPH oxidase produced by neutrophils was essential to control the growth of Aspergillus and Fusarium fungi in the cornea. We demonstrated that neutrophil oxidant production and antifungal activity are dependent on CD18, but not on the β-glucan receptor dectin-1. We used mutant A. fumigatus strains to show that the reactive oxygen species-sensing transcription factor Yap1, superoxide dismutases, and the Yap1-regulated thioredoxin antioxidant pathway are each required for protection against neutrophil-mediated oxidation of hyphae as well as optimal survival of fungal hyphae in vivo. We also demonstrated that thioredoxin inhibition using the anticancer drug PX-12 increased the sensitivity of fungal hyphae to both H2O2- and neutrophil-mediated killing in vitro. Additionally, topical application of PX-12 significantly enhanced neutrophil-mediated fungal killing in infected mouse corneas. Cumulatively, our data reveal critical host oxidative and fungal anti-oxidative mediators that regulate hyphal survival during infection. Further, these findings also indicate that targeting fungal anti-oxidative defenses via PX-12 may represent an efficacious strategy for treating fungal infections.
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Affiliation(s)
- Sixto M Leal
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, OH 44106, USA
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62
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Kłossowski S, Muchowicz A, Firczuk M, Świech M, Redzej A, Golab J, Ostaszewski R. Studies toward Novel Peptidomimetic Inhibitors of Thioredoxin–Thioredoxin Reductase System. J Med Chem 2011; 55:55-67. [DOI: 10.1021/jm201359d] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Szymon Kłossowski
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224
Warsaw, Poland
| | - Angelika Muchowicz
- Department
of Immunology, Center
of Biostructure Research, Medical University of Warsaw, Banacha 1A, F building, 02-097 Warsaw, Poland
| | - Małgorzata Firczuk
- Department
of Immunology, Center
of Biostructure Research, Medical University of Warsaw, Banacha 1A, F building, 02-097 Warsaw, Poland
| | - Marta Świech
- Department
of Immunology, Center
of Biostructure Research, Medical University of Warsaw, Banacha 1A, F building, 02-097 Warsaw, Poland
| | - Adam Redzej
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224
Warsaw, Poland
| | - Jakub Golab
- Department
of Immunology, Center
of Biostructure Research, Medical University of Warsaw, Banacha 1A, F building, 02-097 Warsaw, Poland
| | - Ryszard Ostaszewski
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224
Warsaw, Poland
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63
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Ramanathan RK, Stephenson JJ, Weiss GJ, Pestano LA, Lowe A, Hiscox A, Leos RA, Martin JC, Kirkpatrick L, Richards DA. A phase I trial of PX-12, a small-molecule inhibitor of thioredoxin-1, administered as a 72-hour infusion every 21 days in patients with advanced cancers refractory to standard therapy. Invest New Drugs 2011; 30:1591-6. [PMID: 21863237 DOI: 10.1007/s10637-011-9739-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Accepted: 08/16/2011] [Indexed: 12/27/2022]
Abstract
PURPOSE This phase I trial assessed the safety, dose limiting toxicity (DLT) and pharmacodynamics of PX-12 in adult patients with advanced refractory cancers. METHODS PX-12 was administered to sequential cohorts as a 72-h infusion utilizing a portable infusion pump on days 1, 2, and 3 of a 21-day cycle at a starting dose level of 300 mg/m(2)/day and escalating dose levels till DLT was observed. Plasma thioredoxin (Trx-1), vascular endothelial growth factor (VEGF) and FGF-2 (fibroblast growth factor) levels were measured predose and during infusion of PX-12. RESULTS Patients (n = 14) were enrolled to the following dose cohorts, 300 mg/m(2) (n = 3), 400 mg/m(2) (n = 10) and 500 mg/m(2) (n = 1). Common grade 1/2 toxicities included fatigue, taste alteration and odor caused by expired drug metabolite. DLTs were one episode each of grade 3 hypoxia at the 400 mg/m(2) and grade 3 reversible pneumonitis at the 500 mg/m(2) dose levels. Best response was stable disease in a patient with rectal cancer. Predose Trx-1 levels (n = 12) ranged from 5.1 to 30.0 ng/mL (median 12.6 ng/mL). CONCLUSION PX-12 administered at 400 mg/m(2)/day by 72-hour infusion appears safe and tolerable. Inhibition of thioredoxin is a strategy worth evaluation with next generation of inhibitors.
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Laroche C, Li J, Kerwin SM. Cytotoxic 1,2-dialkynylimidazole-based aza-enediynes: aza-Bergman rearrangement rates do not predict cytotoxicity. J Med Chem 2011; 54:5059-69. [PMID: 21667990 DOI: 10.1021/jm200289j] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new class of potential antitumor agents inspired by the enediyne antitumor antibiotics has been synthesized: the 1,2-dialkynylimidazoles. The aza-Bergman rearrangement of these 1,2-dialkynylimidazoles has been investigated theoretically at the B3LYP/6-31G(d,p) level and experimentally by measuring the kinetics of rearrangement in 1,4-cyclohexadiene. There is a good correlation between the theoretical and experimental results; subtle substituent effects on the initial aza-Bergman cyclization barrier predicted by theory are confirmed by experiment. Yet, despite the ability of these 1,2-dialkynylimidazoles to undergo Bergman rearrangement to diradical/carbene intermediates under relatively mild conditions, there is no correlation between the rate of Bergman cyclization and cytotoxicity to A459 cells. In addition, cytotoxic 1,2-dialkynylimidazoles do not cause nicking of supercoiled plasmid DNA or cleavage of bovine serum albumin. An alternative mechanism for cytotoxicity involving the unexpected selective thiol addition to the N-ethynyl group of certain 1,2-dialkynylimidazoles is proposed.
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Affiliation(s)
- Christophe Laroche
- Division of Medicinal Chemistry, College of Pharmacy, The University of Texas at Austin, Texas 78712, USA
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Ban HS, Uto Y, Nakamura H. Hypoxia-inducible factor inhibitors: a survey of recent patented compounds (2004 – 2010). Expert Opin Ther Pat 2011; 21:131-46. [DOI: 10.1517/13543776.2011.547477] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Patenaude A, Fortin JS, Deschenes R, Côté MF, Lacroix J, C.-Gaudreault R, Petitclerc É. Chloroethyl urea derivatives block tumour growth and thioredoxin-1 nuclear translocation. Can J Physiol Pharmacol 2010; 88:1102-14. [DOI: 10.1139/y10-084] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Aryl chloroethyl ureas (CEUs) are new protein alkylating agents exhibiting anticancer activity both in vitro and in vivo. We report herein that 14C-labeled CEU derivatives, designated CEU-025 and CEU-027, covalently bind to thioredoxin-1 (TRX1). Covalent binding of these molecules slightly decreases the disulfide-reducing activity of recombinant TRX1, when compared with the effect of strong thioalkylating agents such as N-ethylmaleimide. Moreover, site-directed mutagenesis and diamide competition assays demonstrated that TRX1 cysteinyl residues are not the prime targets of CEUs. CEU-025 abrogates the nuclear translocation of TRX1 in human cancer cells. In addition, we show that CEU-025 can block TRX1 nuclear translocation induced by cisplatin. Unexpectedly, pretreatment with sublethal CEU-025 concentrations that block TRX1 nuclear translocation protected the cells against cisplatin cytotoxicity. Overexpression of TRX1 in HT1080 fibrosarcoma cells attenuated CEU-025 cytotoxicity, while its suppression using TRX1-specific siRNA increased the effects of CEU-025, suggesting that loss of function of TRX1 is involved, at least in part, in the cytotoxic activity of CEU-025. These results suggest that CEU-025 and CEU-027 exhibit anticancer activity through a novel, unique mechanism of action. The importance of TRX1 and the dependence of the cytotoxicity of CEU-025 and CEU-027 on TRX1 intracellular localization are also discussed.
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Affiliation(s)
- Alexandre Patenaude
- Unité de Biotechnologie et de Bioingénierie, CHUQ, Hôpital Saint-François d’Assise, Université Laval, Québec, QC, Canada
- Héma-Québec, Ingénierie cellulaire, Québec, QC, Canada
| | - Jessica S. Fortin
- Unité de Biotechnologie et de Bioingénierie, CHUQ, Hôpital Saint-François d’Assise, Université Laval, Québec, QC, Canada
- Héma-Québec, Ingénierie cellulaire, Québec, QC, Canada
| | - Réna Deschenes
- Unité de Biotechnologie et de Bioingénierie, CHUQ, Hôpital Saint-François d’Assise, Université Laval, Québec, QC, Canada
- Héma-Québec, Ingénierie cellulaire, Québec, QC, Canada
| | - Marie-France Côté
- Unité de Biotechnologie et de Bioingénierie, CHUQ, Hôpital Saint-François d’Assise, Université Laval, Québec, QC, Canada
- Héma-Québec, Ingénierie cellulaire, Québec, QC, Canada
| | - Jacques Lacroix
- Unité de Biotechnologie et de Bioingénierie, CHUQ, Hôpital Saint-François d’Assise, Université Laval, Québec, QC, Canada
- Héma-Québec, Ingénierie cellulaire, Québec, QC, Canada
| | - René C.-Gaudreault
- Unité de Biotechnologie et de Bioingénierie, CHUQ, Hôpital Saint-François d’Assise, Université Laval, Québec, QC, Canada
- Héma-Québec, Ingénierie cellulaire, Québec, QC, Canada
| | - Éric Petitclerc
- Unité de Biotechnologie et de Bioingénierie, CHUQ, Hôpital Saint-François d’Assise, Université Laval, Québec, QC, Canada
- Héma-Québec, Ingénierie cellulaire, Québec, QC, Canada
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Abstract
Angiogenesis has become an attractive target for drug therapy because of its key role in tumor growth. An extensive array of compounds is currently in preclinical development, with many now entering the clinic and/or achieving approval from the US Food and Drug Administration. Several regulatory and signaling molecules governing angiogenesis are of interest, including growth factors (eg, vascular endothelial growth factor, platelet-derived growth factor, fibroblast growth factor, and epidermal growth factor), receptor tyrosine kinases, and transcription factors such as hypoxia inducible factor, as well as molecules involved in mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K) signaling. Pharmacologic agents have been identified that target these pathways, yet for some agents (notably thalidomide), an understanding of the specific mechanisms of antitumor action has proved elusive. The following review describes key molecular mechanisms and novel therapies that are on the horizon for antiangiogenic tumor therapy.
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Affiliation(s)
| | - William D. Figg
- To whom correspondence should be addressed: 10 Center Drive, 9000 Rockville Pike, Building 10, Room 5A01, Bethesda, MD 20892 USA Phone: 301-402-3622 Fax: 301-402-8606
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Ren YJ, Yang L, Zhai ZH. Clinical value of inhibition of vascular endothelial growth factor in primary hepatocellular carcinoma after transcatheter arterial chemoembolization. Shijie Huaren Xiaohua Zazhi 2010; 18:1582-1587. [DOI: 10.11569/wcjd.v18.i15.1582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Vascular endothelial growth factor (VEGF) is a well-known potent angiogenic factor that correlates with tumor invasion and metastasis. Primary hepatocellular carcinoma (PHC) is a common highly malignant vascular tumor with a very high mortality. Angiogenesis is considered to be important for PHC progression. Transarterial chemoembolization (TACE) has been proved to be effective for unresectable PHC. This paper aims to make a literature review of the recent advances in understanding the clinical value of inhibition of VEGF in PHC after interventional therapy.
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Ramanathan RK, Abbruzzese J, Dragovich T, Kirkpatrick L, Guillen JM, Baker AF, Pestano LA, Green S, Von Hoff DD. A randomized phase II study of PX-12, an inhibitor of thioredoxin in patients with advanced cancer of the pancreas following progression after a gemcitabine-containing combination. Cancer Chemother Pharmacol 2010; 67:503-9. [PMID: 20461382 DOI: 10.1007/s00280-010-1343-8] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Accepted: 04/22/2010] [Indexed: 12/27/2022]
Abstract
PURPOSE This study evaluated PX-12, a novel small molecule inhibitor of the proto-oncogene (Trx-1), in patients with previously treated advanced pancreatic cancer (APC). METHODS PX-12 (54 or 128 mg/m²) was administered by 3-hour IV infusion daily × 5 days every 21 days (n = 17). Patients were randomized to either 54 or 128 mg/m² and then stratified based on CA 19-9 level (≥ 1,000 vs. < 1,000 U/ml) and SUV values on PET scans (≥ 7.0 vs. <7.0). The primary endpoint was based on a progression-free survival (PFS) at 4 months in ≥ 40% of patients, and required 40 patients in each arm. An amendment required elevated Trx-1 levels (> 18 ng/ml) as an entry criteria after the first 17 patients were accrued. RESULTS Plasma Trx-1 levels were elevated in 3/28 (11%) patients screened for study. The grade of the expired metabolite odor was higher in the 128 mg/m² arm. Therapy was well tolerated, and Grade ≥ 3 adverse events were uncommon. The best response was stable disease in 2 patients. There was no consistent decrease in SUV, Trx-1 levels or CA 19-9 levels with therapy. No patients had a PFS of >4 months. Median PFS and survival were 0.9 months (95% CI 0.5-1.2) and 3.2 months (95% CI 2.4-4.2), respectively. CONCLUSIONS Due to the lack of significant antitumor activity and unexpectedly low baseline Trx-1 levels, the study was terminated early. PX-12 does not appear to be active in unselected patients with previously treated APC.
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70
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Landriscina M, Maddalena F, Laudiero G, Esposito F. Adaptation to oxidative stress, chemoresistance, and cell survival. Antioxid Redox Signal 2009; 11:2701-16. [PMID: 19778285 DOI: 10.1089/ars.2009.2692] [Citation(s) in RCA: 166] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The discovery of some additional properties and functions of reactive oxygen species (ROS), beyond their toxic effects, provides a novel scenario for the molecular basis and cell regulation of several pathophysiologic processes. ROS are generated by redox-sensitive, prosurvival signaling pathways and function as second messengers in the transduction of several extracellular signals. A complex intracellular redox buffering network has developed to adapt and protect cells against the dangerous effects of oxidative stress. However, pathways involved in ROS-adaptive response may also play a critical role in protecting cells against cytotoxic effects of anticancer agents, thus supporting the hypothesis of a correlation between adaptation/resistance to oxidative stress and resistance to anticancer drugs. This review summarizes the main systems involved in the adaptive responses: an overview on the pathophysiologic relevance of mitochondria on redox-sensitive transcription factors and genes and main antioxidant networks in tumor cells is provided. One of the major aims is to highlight the adaptive mechanisms and their interplay in the intricate connection between oncogenic signaling, oxidative stress, and chemoresistance. Clarification of these mechanisms has tremendous application potential, in terms of developing novel molecular-targeted anticancer therapies and innovative strategies for rational combination of these agents with chemotherapeutic or tumor-specific biologic drugs.
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Affiliation(s)
- Matteo Landriscina
- Clinical Oncology Unit, Department of Medical Sciences, University of Foggia, Foggia, Italy
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71
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Kuljaca S, Liu T, Dwarte T, Kavallaris M, Haber M, Norris MD, Martin-Caballero J, Marshall GM. The cyclin-dependent kinase inhibitor, p21(WAF1), promotes angiogenesis by repressing gene transcription of thioredoxin-binding protein 2 in cancer cells. Carcinogenesis 2009; 30:1865-71. [PMID: 19773351 DOI: 10.1093/carcin/bgp225] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The cyclin-dependent kinase inhibitor, p21(WAF1), induces cell-cycle arrest and can act as a tumor suppressor. However, increasing evidence indicates that p21(WAF1) can also increase resistance to some anticancer therapies and thus promote tumor growth. The mechanisms explaining this paradox have not been explained. We found that conditioned media from MCF-7 breast cancer cells transfected with a p21(WAF1)-specific small interfering RNA (siRNA) significantly reduced endothelial cell migration, invasion and vascular sprouting. Liquid chromatography/mass spectrometry analysis of the conditioned media revealed that p21(WAF1) knockdown significantly reduced secretion of thioredoxin (Trx), a redox protein known to promote tumor angiogenesis. p21(WAF1) knockdown decreased Trx enzymatic activity in cancer cells, by effects on the expression levels of intracellular thioredoxin-binding protein 2 (TBP2), known to bind and inactivate Trx. Consistent with these findings, media from cancer cells transfected with TBP2 siRNA promoted endothelial cell invasion and blocked the anti-angiogenic effect of p21(WAF1) siRNA. Addition of Trx siRNA blocked the pro-angiogenic effects of TBP2 siRNA. Chromatin immunoprecipitation assays showed p21(WAF1) bound TBP2 gene promoter. Taken together, our data suggests that p21(WAF1) can induce Trx secretion and angiogenesis in cancer cells, by direct transcriptional repression of the TBP2 promoter.
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Affiliation(s)
- Selena Kuljaca
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney 2031, Australia
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72
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Tonissen KF, Di Trapani G. Thioredoxin system inhibitors as mediators of apoptosis for cancer therapy. Mol Nutr Food Res 2009; 53:87-103. [PMID: 18979503 DOI: 10.1002/mnfr.200700492] [Citation(s) in RCA: 176] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The thioredoxin (Trx) system is a major antioxidant system integral to maintaining the intracellular redox state. It contains Trx, a redox active protein, which regulates the activity of various enzymes including those that function to counteract oxidative stress within the cell. Trx can also scavenge reactive oxygen species (ROS) and directly inhibits proapoptotic proteins such as apoptosis signal-regulating kinase 1 (ASK1). The oxidized form of Trx is reduced by thioredoxin reductase (TrxR). The cytoplasm and mitochondria contain equivalent Trx systems and inhibition of either system can lead to activation of apoptotic signaling pathways. There are a number of inhibitors with chemotherapy applications that target either Trx or TrxR to induce apoptosis in cancer cells. Suberoylanilide hydroxamic acid (SAHA) is effective against many cancer cells and functions by up-regulating an endogenous inhibitor of Trx. Other compounds target the selenocysteine-containing active site of TrxR. These include gold compounds, platinum compounds, arsenic trioxide, motexafin gadolinium, nitrous compounds, and various flavonoids. Inhibition of TrxR leads to an accumulation of oxidized Trx resulting in cellular conditions that promote apoptosis. In addition, some compounds also convert TrxR to a ROS generating enzyme. The role of Trx system inhibitors in cancer therapy is discussed in this review.
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Affiliation(s)
- Kathryn F Tonissen
- School of Biomolecular and Physical Sciences, Griffith University, Nathan, Qld, Australia.
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73
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Nigro P, Dal Piaz F, Gallotta D, De Tommasi N, Belisario MA. Inhibition of the thioredoxin system is a basis for the antileukemic potential of 13-hydroxy-15-oxo-zoapatlin. Free Radic Biol Med 2008; 45:875-84. [PMID: 18638547 DOI: 10.1016/j.freeradbiomed.2008.06.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2008] [Revised: 05/28/2008] [Accepted: 06/13/2008] [Indexed: 01/24/2023]
Abstract
The mammalian thioredoxin (Trx) system, composed of Trx, Trx reductase (TrxR), and NADPH, is the most important thiol system involved in the redox control of signaling and regulatory proteins in apoptosis and cell proliferation. Here we addressed the inhibition of the Trx system by 13-hydroxy-15-oxo-zoapatlin (OZ), a nor-kaurane diterpene previously shown to possess proapoptotic potential and to cause cell cycle arrest in leukemia cells. OZ was found, by both biochemical and mass spectrometry-based approaches, to target Trx1 and TrxR in a cell-free system. In particular, the formation of reversible OZ adducts to Trx1 Cys35, Cys62, and Cys73 was demonstrated. We next showed that OZ efficiently inhibited Trx and TrxR catalytic activity in Molt4 cells. The occurrence of oxidative modifications of Trx molecules was assessed by "redox Western blot" analyses. OZ-mediated Trx oxidation resulted in apoptosis signaling kinase-1 release and activation of downstream JNK and p38 pathways. By means of specific inhibitors of these two stress-activated protein kinases, we demonstrated that the JNK pathway plays a major role in determining the apoptotic fate of OZ-exposed cells, whereas p38 activation seems to be involved mainly in OZ-induced G2/M block.
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Affiliation(s)
- Patrizia Nigro
- Dipartimento di Scienze Farmaceutiche, Università di Salerno, Via Ponte Don Melillo, 84084 Fisciano, Salerno, Italy
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Chen Y, Go YM, Pohl J, Reed M, Cai J, Jones DP. Increased mitochondrial thioredoxin 2 potentiates N-ethylmaleimide-induced cytotoxicity. Chem Res Toxicol 2008; 21:1205-10. [PMID: 18447393 DOI: 10.1021/tx800012p] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Thioredoxin 2 (Trx2) is a mitochondrially localized antioxidant and antiapoptotic protein, whose functions are mainly dependent on the conserved cysteines at its redox active center. In the current study, we showed by mass spectrometry that a thiol alkylating agent, N-ethylmaleimide (NEM), alkylated a single cysteine residue in the active center of Trx2. The interaction between NEM and Trx2 in intact cells was confirmed by redox Western analysis. Overexpression of Trx2 in cultured 143B osteosarcoma cells caused increased sensitivity to NEM. Covalent modification by NEM resulted in a dominant-negative effect and increased the interaction between Trx2 and peroxiredoxin 3 (Prx3). Our data suggest that the alkylation of the essential thiol(s) of Trx2 has profound impact on the mitochondrial redox circuitry and that such effects are distinct from the responses to agents causing reversible disulfide bond formation between the vicinal dithiols in the active center.
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Affiliation(s)
- Yan Chen
- Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA
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Huber K, Patel P, Zhang L, Evans H, Westwell AD, Fischer PM, Chan S, Martin S. 2-[(1-methylpropyl)dithio]-1H-imidazole inhibits tubulin polymerization through cysteine oxidation. Mol Cancer Ther 2008; 7:143-51. [PMID: 18202017 DOI: 10.1158/1535-7163.mct-07-0486] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
2-[(1-methylpropyl)dithio]-1H-imidazole (IV-2) is a known inhibitor of the thioredoxin system. It causes the oxidation of cysteine residues from both thioredoxin reductase and thioredoxin, with only the latter leading to irreversible inhibition of protein function. Although IV-2 is considered to be the first specific inhibitor of thioredoxin to undergo evaluation in cancer patients (under the name PX-12), it is unclear whether the oxidative ability of IV-2 is limited to proteins of the thioredoxin family. The current study investigated the specificity of IV-2 by examining its interaction with tubulin, a protein in which cysteine oxidation causes loss of polymerization competence. The cellular effects of IV-2 were examined in MCF-7 breast cancer and endothelial cells (human umbilical vein endothelial cells). Immunocytochemistry revealed a loss of microtubule structure with Western blot analysis confirming that treated cells contained a higher proportion of unpolymerized tubulin. Cell-free tubulin polymerization assays showed a dose-dependent inhibition of tubulin polymerization and depolymerization of preformed microtubules, confirming a direct interaction between IV-2 and tubulin. Further investigation of the tubulin interaction, through analysis of sulfhydryl reactivity and disulfide bond formation, suggested that IV-2 acts through the oxidation of cysteines in tubulin. Biochemical assays indicated that the oxidative properties of IV-2 are not limited to thioredoxin and tubulin, as cysteine-dependent proteases were also inhibited. Breast cancer cells with thioredoxin silenced by short interfering RNA remained sensitive to IV-2, albeit at higher antiproliferative GI50 values than in cells with normal thioredoxin function. These findings show that modulation of targets other than thioredoxin contribute to the effects of IV-2 on proliferating cells.
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Affiliation(s)
- Kelly Huber
- School of Molecular Medical Sciences, Division of Clinical Oncology, University of Nottingham, Nottingham University Hospitals, City Hospital Campus, Nottingham NG5 1PB, United Kingdom
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Adamski JK, Estlin EJ, Makin GWJ. The cellular adaptations to hypoxia as novel therapeutic targets in childhood cancer. Cancer Treat Rev 2008; 34:231-46. [PMID: 18207646 DOI: 10.1016/j.ctrv.2007.11.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2007] [Revised: 11/26/2007] [Accepted: 11/27/2007] [Indexed: 01/19/2023]
Abstract
Exposure of tumour cells to reduced levels of oxygen (hypoxia) is a common finding in adult tumours. Hypoxia induces a myriad of adaptive changes within tumour cells which result in increased anaerobic glycolysis, new blood vessel formation, genetic instability and a decreased responsiveness to both radio and chemotherapy. Hypoxia correlates with disease stage and outcome in adult epithelial tumours and increasingly it is becoming apparent that hypoxia is also important in paediatric tumours. Despite its adverse effects upon tumour response to treatment hypoxia offers several avenues for new drug development. Bioreductive agents already exist, which are preferentially activated in areas of hypoxia, and thus have less toxicity for normal tissue. Additionally the adaptive cellular response to hypoxia offers several novel targets, including vascular endothelial growth factor (VEGF), carbonic anhydrase, and the central regulator of the cellular response to hypoxia, hypoxia inducible factor-1 (HIF-1). Novel agents have emerged against all of these targets and are at various stages of clinical and pre-clinical development. Hypoxia offers an exciting opportunity for new drug development that can include paediatric tumours at an early stage.
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Affiliation(s)
- J K Adamski
- School of Cancer and Imaging Studies, Faculty of Medical and Human Studies, University of Manchester, United Kingdom.
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Kaimul AM, Nakamura H, Masutani H, Yodoi J. Thioredoxin and thioredoxin-binding protein-2 in cancer and metabolic syndrome. Free Radic Biol Med 2007; 43:861-8. [PMID: 17697931 DOI: 10.1016/j.freeradbiomed.2007.05.032] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2007] [Revised: 05/25/2007] [Accepted: 05/25/2007] [Indexed: 12/27/2022]
Abstract
Thioredoxin (TRX), a small redox-active multifunctional protein, acts as a potent antioxidant and a redox regulator in signal transduction. TRX expression is elevated in various types of human cancer. Overexpression of TRX introduces resistance to anti-cancer drugs or radiation-induced apoptosis; however, there is no evidence that the incidence of cancer is frequent in TRX-transgenic mice or that the administration of recombinant human TRX enhances tumor growth. Plasma/serum level of TRX is a good marker for oxidative stress-induced various disorders, including metabolic syndrome. Thioredoxin-binding protein-2 (TBP-2), which was originally identified as a negative regulator of TRX, acts as a growth suppressor and a regulator in lipid metabolism. TBP-2 expression is downregulated in various types of human cancer. TBP-2 deficiency induces lipid dysfunction and a phenotype resembling Reye syndrome. Thus, TRX and TBP-2 play important roles in the pathophysiology of cancer and metabolic syndrome by direct interaction or by independent mechanisms.
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Affiliation(s)
- Ahsan M Kaimul
- Thioredoxin Project, Department of Experimental Therapeutics, Translational Research Center, Kyoto University Hospital, 54 Shogoin, Kawahara-cho, Sakyo, Kyoto 606-8507, Japan
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78
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Powis G, Kirkpatrick DL. Thioredoxin signaling as a target for cancer therapy. Curr Opin Pharmacol 2007; 7:392-7. [PMID: 17611157 DOI: 10.1016/j.coph.2007.04.003] [Citation(s) in RCA: 208] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2007] [Revised: 04/12/2007] [Accepted: 04/16/2007] [Indexed: 11/29/2022]
Abstract
Thioredoxin (Trx) family members play critical roles in the regulation of cellular redox homeostasis. Cancer cells exist in a stressed environment and rely on the Trxs for protection against stress-disregulated redox signaling. The most extensively studied member of the family is Trx-1 whose levels are increased in many human cancers most likely in direct response to stress. Trx-1 contributes to many of the hallmarks of cancer including increased proliferation, resistance to cell death and increased angiogenesis. Trx-1 is a validated cancer drug target associated with aggressive tumor growth, resistance to standard therapy and decreased patient survival. A surrogate target for Trx-1 may be thioredoxin reductase (TR). Drugs that inhibit Trx-1 and TR are in clinical development with early promising results.
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Affiliation(s)
- Garth Powis
- Department of Experimental Therapeutics, MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030-4009, USA.
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