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Yao L, Zhu X, Shan Y, Zhang L, Yao J, Xiong H. Recent Progress in Anti-Tumor Nanodrugs Based on Tumor Microenvironment Redox Regulation. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2310018. [PMID: 38269480 DOI: 10.1002/smll.202310018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 12/30/2023] [Indexed: 01/26/2024]
Abstract
The growth state of tumor cells is strictly affected by the specific abnormal redox status of the tumor microenvironment (TME). Moreover, redox reactions at the biological level are also central and fundamental to essential energy metabolism reactions in tumors. Accordingly, anti-tumor nanodrugs targeting the disruption of this abnormal redox homeostasis have become one of the hot spots in the field of nanodrugs research due to the effectiveness of TME modulation and anti-tumor efficiency mediated by redox interference. This review discusses the latest research results of nanodrugs in anti-tumor therapy, which regulate the levels of oxidants or reductants in TME through a variety of therapeutic strategies, ultimately breaking the original "stable" redox state of the TME and promoting tumor cell death. With the gradual deepening of study on the redox state of TME and the vigorous development of nanomaterials, it is expected that more anti-tumor nano drugs based on tumor redox microenvironment regulation will be designed and even applied clinically.
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Affiliation(s)
- Lan Yao
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, Department of Pharmaceutics, China Pharmaceutical University, 639 Longmian Avenue, Nanjing, 211198, P. R. China
| | - Xiang Zhu
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, Department of Pharmaceutics, China Pharmaceutical University, 639 Longmian Avenue, Nanjing, 211198, P. R. China
| | - Yunyi Shan
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, Department of Pharmaceutics, China Pharmaceutical University, 639 Longmian Avenue, Nanjing, 211198, P. R. China
| | - Liang Zhang
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, Department of Pharmaceutics, China Pharmaceutical University, 639 Longmian Avenue, Nanjing, 211198, P. R. China
| | - Jing Yao
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, Department of Pharmaceutics, China Pharmaceutical University, 639 Longmian Avenue, Nanjing, 211198, P. R. China
| | - Hui Xiong
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, Department of Pharmaceutics, China Pharmaceutical University, 639 Longmian Avenue, Nanjing, 211198, P. R. China
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Spin Trapping Hydroxyl and Aryl Radicals of One-Electron Reduced Anticancer Benzotriazine 1,4-Dioxides. Molecules 2022; 27:molecules27030812. [PMID: 35164077 PMCID: PMC8840461 DOI: 10.3390/molecules27030812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/19/2022] [Accepted: 01/21/2022] [Indexed: 02/06/2023] Open
Abstract
Hypoxia in tumors results in resistance to both chemotherapy and radiotherapy treatments but affords an environment in which hypoxia-activated prodrugs (HAP) are activated upon bioreduction to release targeted cytotoxins. The benzotriazine 1,4-di-N-oxide (BTO) HAP, tirapazamine (TPZ, 1), has undergone extensive clinical evaluation in combination with radiotherapy to assist in the killing of hypoxic tumor cells. Although compound 1 did not gain approval for clinical use, it has spurred on the development of other BTOs, such as the 3-alkyl analogue, SN30000, 2. There is general agreement that the cytotoxin(s) from BTOs arise from the one-electron reduced form of the compounds. Identifying the cytotoxic radicals, and whether they play a role in the selective killing of hypoxic tumor cells, is important for continued development of the BTO class of anticancer prodrugs. In this study, nitrone spin-traps, combined with electron spin resonance, give evidence for the formation of aryl radicals from compounds 1, 2 and 3-phenyl analogues, compounds 3 and 4, which form carbon C-centered radicals. In addition, high concentrations of DEPMPO (5-(diethoxyphosphoryl)-5-methyl-1-pyrroline N-oxide) spin-trap the •OH radical. The combination of spin-traps with high concentrations of DMSO and methanol also give evidence for the involvement of strongly oxidizing radicals. The failure to spin-trap methyl radicals with PBN (N-tert-butylphenylnitrone) on the bioreduction of compound 2, in the presence of DMSO, implies that free •OH radicals are not released from the protonated radical anions of compound 2. The spin-trapping of •OH radicals by high concentrations of DEPMPO, and the radical species arising from DMSO and methanol give both direct and indirect evidence for the scavenging of •OH radicals that are involved in an intramolecular process. Hypoxia-selective cytotoxicity is not related to the formation of aryl radicals from the BTO compounds as they are associated with high aerobic cytotoxicity.
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Kang M, Zhang Z, Xu W, Wen H, Zhu W, Wu Q, Wu H, Gong J, Wang Z, Wang D, Tang BZ. Good Steel Used in the Blade: Well-Tailored Type-I Photosensitizers with Aggregation-Induced Emission Characteristics for Precise Nuclear Targeting Photodynamic Therapy. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2100524. [PMID: 34021726 PMCID: PMC8292883 DOI: 10.1002/advs.202100524] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 03/20/2021] [Indexed: 05/21/2023]
Abstract
Photodynamic therapy (PDT) has long been recognized to be a promising approach for cancer treatment. However, the high oxygen dependency of conventional PDT dramatically impairs its overall therapeutic efficacy, especially in hypoxic solid tumors. Exploration of distinctive PDT strategy involving both high-performance less-oxygen-dependent photosensitizers (PSs) and prominent drug delivery system is an appealing yet significantly challenging task. Herein, a precise nuclear targeting PDT protocol based on type-I PSs with aggregation-induced emission (AIE) characteristics is fabricated for the first time. Of the two synthesized AIE PSs, TTFMN is demonstrated to exhibit superior AIE property and stronger type-I reactive oxygen species (ROS) generation efficiency owing to the introduction of tetraphenylethylene and smaller singlet-triplet energy gap, respectively. With the aid of a lysosomal acid-activated TAT-peptide-modified amphiphilic polymer poly(lactic acid)12k-poly(ethylene glycol)5k-succinic anhydride-modified TAT, the corresponding TTFMN-loaded nanoparticles accompanied with acid-triggered nuclear targeting peculiarity can quickly accumulate in the tumor site, effectively generate type-I ROS in the nuclear region and significantly suppress the tumor growth under white light irradiation with minimized systematic toxicity. This delicate "Good Steel Used in the Blade" tactic significantly maximizes the PDT efficacy and offers a conceptual while practical paradigm for optimized cancer treatment in further translational medicine.
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Affiliation(s)
- Miaomiao Kang
- Center for AIE ResearchShenzhen Key Laboratory of Polymer Science and TechnologyGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen518060China
| | - Zhijun Zhang
- Center for AIE ResearchShenzhen Key Laboratory of Polymer Science and TechnologyGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen518060China
| | - Wenhan Xu
- Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionDepartment of ChemistryThe Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong999077China
| | - Haifei Wen
- Center for AIE ResearchShenzhen Key Laboratory of Polymer Science and TechnologyGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen518060China
| | - Wei Zhu
- Center for AIE ResearchShenzhen Key Laboratory of Polymer Science and TechnologyGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen518060China
| | - Qian Wu
- Center for AIE ResearchShenzhen Key Laboratory of Polymer Science and TechnologyGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen518060China
| | - Hongzhuo Wu
- Center for AIE ResearchShenzhen Key Laboratory of Polymer Science and TechnologyGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen518060China
| | - Junyi Gong
- Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionDepartment of ChemistryThe Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong999077China
| | - Zhijia Wang
- State Key Laboratory of Fine ChemicalsSchool of Chemical EngineeringDalian University of TechnologyDalian116024China
| | - Dong Wang
- Center for AIE ResearchShenzhen Key Laboratory of Polymer Science and TechnologyGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen518060China
| | - Ben Zhong Tang
- Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionDepartment of ChemistryThe Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong999077China
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Wang Y, Zhang S, Wang J, Zhou Q, Mukerabigwi JF, Ke W, Lu N, Ge Z. Ferrocene-containing polymersome nanoreactors for synergistically amplified tumor-specific chemodynamic therapy. J Control Release 2021; 333:500-510. [PMID: 33848558 DOI: 10.1016/j.jconrel.2021.04.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 04/05/2021] [Accepted: 04/08/2021] [Indexed: 02/08/2023]
Abstract
Chemodynamic therapy (CDT) has been proposed to convert tumoral H2O2 into toxic hydroxyl radicals (OH) via Fenton or Fenton-like reactions for antitumor efficacy, which is frequently limited by low H2O2 concentrations or lack of enough metal ions inside tumor tissues. In this report, we present ferrocene-containing responsive polymersome nanoreactors via loading glucose oxidase (GOD) and hypoxia-activable prodrug tirapazamine (TPZ) in the inner aqueous cavities. After intravenous injection, the polymersome nanoreactors with the optimized nanoparticle size of ~100 nm and poly(ethylene glycol) corona facilitate tumor accumulation. The tumor acidic microenvironment can trigger the permeability of the polymersome membranes to activate the nanoreactors and release the loaded TPZ prodrugs. Tumor oxygen and glucose can enter the polymersome nanoreactors and are transformed into H2O2 under the catalysis of GOD, which are further converted into OH via Fenton reaction under catalysis of ferrocene moieties. The oxygen consumption can aggravate tumor hypoxia to activate hypoxia-responsive TPZ prodrugs which can produce benzotriazinyl (BTZ) radicals and OH. All the produced radicals synergistically kill tumor cells via the amplified CDT and suppress the tumor growth efficiently. Thus, the ferrocene-containing responsive polymersome nanoreactors loading GOD and TPZ represent a potent nanoplatform to exert amplified CDT for improved anticancer efficacy.
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Affiliation(s)
- Yuheng Wang
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Shuang Zhang
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Jingbo Wang
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Qinghao Zhou
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Jean Felix Mukerabigwi
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Wendong Ke
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Nannan Lu
- Department of Oncology, The First Affiliated Hospital of USTC, Division of Life Science and Medicine, University of Science and Technology of China, Hefei 230001, Anhui, China
| | - Zhishen Ge
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China.
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Evans MA, Shields CW, Krishnan V, Wang LL, Zhao Z, Ukidve A, Lewandowski M, Gao Y, Mitragotri S. Macrophage‐Mediated Delivery of Hypoxia‐Activated Prodrug Nanoparticles. ADVANCED THERAPEUTICS 2019. [DOI: 10.1002/adtp.201900162] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Michael A. Evans
- John A. Paulson School of Engineering and Applied SciencesHarvard University 29 Oxford St. Cambridge MA 02138 USA
- Wyss Institute for Biologically Inspired EngineeringHarvard University Cambridge MA 02138 USA
| | - C. Wyatt Shields
- John A. Paulson School of Engineering and Applied SciencesHarvard University 29 Oxford St. Cambridge MA 02138 USA
- Wyss Institute for Biologically Inspired EngineeringHarvard University Cambridge MA 02138 USA
| | - Vinu Krishnan
- John A. Paulson School of Engineering and Applied SciencesHarvard University 29 Oxford St. Cambridge MA 02138 USA
- Wyss Institute for Biologically Inspired EngineeringHarvard University Cambridge MA 02138 USA
| | - Lily Li‐Wen Wang
- John A. Paulson School of Engineering and Applied SciencesHarvard University 29 Oxford St. Cambridge MA 02138 USA
- Wyss Institute for Biologically Inspired EngineeringHarvard University Cambridge MA 02138 USA
- Harvard‐MIT Division of Health Sciences and TechnologyMassachusetts Institute of Technology Cambridge MA 02139 USA
| | - Zhongmin Zhao
- John A. Paulson School of Engineering and Applied SciencesHarvard University 29 Oxford St. Cambridge MA 02138 USA
- Wyss Institute for Biologically Inspired EngineeringHarvard University Cambridge MA 02138 USA
| | - Anvay Ukidve
- John A. Paulson School of Engineering and Applied SciencesHarvard University 29 Oxford St. Cambridge MA 02138 USA
- Wyss Institute for Biologically Inspired EngineeringHarvard University Cambridge MA 02138 USA
| | - Michael Lewandowski
- Wyss Institute for Biologically Inspired EngineeringHarvard University Cambridge MA 02138 USA
| | - Yongsheng Gao
- John A. Paulson School of Engineering and Applied SciencesHarvard University 29 Oxford St. Cambridge MA 02138 USA
- Wyss Institute for Biologically Inspired EngineeringHarvard University Cambridge MA 02138 USA
| | - Samir Mitragotri
- John A. Paulson School of Engineering and Applied SciencesHarvard University 29 Oxford St. Cambridge MA 02138 USA
- Wyss Institute for Biologically Inspired EngineeringHarvard University Cambridge MA 02138 USA
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Photothermal-pH-hypoxia responsive multifunctional nanoplatform for cancer photo-chemo therapy with negligible skin phototoxicity. Biomaterials 2019; 221:119422. [DOI: 10.1016/j.biomaterials.2019.119422] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 07/26/2019] [Accepted: 08/11/2019] [Indexed: 12/17/2022]
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Hay MP, Shin HN, Wong WW, Sahimi WW, Vaz ATD, Yadav P, Anderson RF, Hicks KO, Wilson WR. Benzotriazine Di-Oxide Prodrugs for Exploiting Hypoxia and Low Extracellular pH in Tumors. Molecules 2019; 24:E2524. [PMID: 31295864 PMCID: PMC6680510 DOI: 10.3390/molecules24142524] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 07/05/2019] [Accepted: 07/06/2019] [Indexed: 12/31/2022] Open
Abstract
Extracellular acidification is an important feature of tumor microenvironments but has yet to be successfully exploited in cancer therapy. The reversal of the pH gradient across the plasma membrane in cells that regulate intracellular pH (pHi) has potential to drive the selective uptake of weak acids at low extracellular pH (pHe). Here, we investigate the dual targeting of low pHe and hypoxia, another key feature of tumor microenvironments. We prepared eight bioreductive prodrugs based on the benzotriazine di-oxide (BTO) nucleus by appending alkanoic or aminoalkanoic acid sidechains. The BTO acids showed modest selectivity for both low pHe (pH 6.5 versus 7.4, ratios 2 to 5-fold) and anoxia (ratios 2 to 8-fold) in SiHa and FaDu cell cultures. Related neutral BTOs were not selective for acidosis, but had greater cytotoxic potency and hypoxic selectivity than the BTO acids. Investigation of the uptake and metabolism of representative BTO acids confirmed enhanced uptake at low pHe, but lower intracellular concentrations than expected for passive diffusion. Further, the modulation of intracellular reductase activity and competition by the cell-excluded electron acceptor WST-1 suggests that the majority of metabolic reductions of BTO acids occur at the cell surface, compromising the engagement of the resulting free radicals with intracellular targets. Thus, the present study provides support for designing bioreductive prodrugs that exploit pH-dependent partitioning, suggesting, however, that that the approach should be applied to prodrugs with obligate intracellular activation.
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Affiliation(s)
- Michael P Hay
- Auckland Cancer Society Research Centre, School of Medical Sciences, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1142, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Symonds St, Auckland 1142, New Zealand
| | - Hong Nam Shin
- Auckland Cancer Society Research Centre, School of Medical Sciences, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1142, New Zealand
| | - Way Wua Wong
- Auckland Cancer Society Research Centre, School of Medical Sciences, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1142, New Zealand
| | - Wan Wan Sahimi
- School of Chemical Sciences, University of Auckland, Auckland 1142, New Zealand
| | - Aaron T D Vaz
- Auckland Cancer Society Research Centre, School of Medical Sciences, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1142, New Zealand
| | - Pooja Yadav
- Auckland Cancer Society Research Centre, School of Medical Sciences, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1142, New Zealand
| | - Robert F Anderson
- Auckland Cancer Society Research Centre, School of Medical Sciences, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1142, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Symonds St, Auckland 1142, New Zealand
- School of Chemical Sciences, University of Auckland, Auckland 1142, New Zealand
| | - Kevin O Hicks
- Auckland Cancer Society Research Centre, School of Medical Sciences, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1142, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Symonds St, Auckland 1142, New Zealand
| | - William R Wilson
- Auckland Cancer Society Research Centre, School of Medical Sciences, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1142, New Zealand.
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Symonds St, Auckland 1142, New Zealand.
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8
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Shen X, Gates KS. Enzyme-Activated Generation of Reactive Oxygen Species from Heterocyclic N-Oxides under Aerobic and Anaerobic Conditions and Its Relevance to Hypoxia-Selective Prodrugs. Chem Res Toxicol 2019; 32:348-361. [PMID: 30817135 DOI: 10.1021/acs.chemrestox.9b00036] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Enzymatic one-electron reduction of heterocyclic N-oxides can lead to the intracellular generation of reactive oxygen species via several different chemical pathways. These reactions may be relevant to hypoxia-selective anticancer drugs, antimicrobial agents, and unwanted toxicity of heterocylic nitrogen compounds.
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Jackson RK, Liew LP, Hay MP. Overcoming Radioresistance: Small Molecule Radiosensitisers and Hypoxia-activated Prodrugs. Clin Oncol (R Coll Radiol) 2019; 31:290-302. [PMID: 30853148 DOI: 10.1016/j.clon.2019.02.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 02/12/2019] [Indexed: 12/25/2022]
Abstract
The role of hypoxia in radiation resistance is well established and many approaches to overcome hypoxia in tumours have been explored, with variable success. Two small molecule strategies for targeting hypoxia have dominated preclinical and clinical efforts. One approach has been the use of electron-affinic nitroheterocycles as oxygen-mimetic sensitisers. These agents are best exemplified by the 5-nitroimidazole nimorazole, which has limited use in conjunction with radiotherapy in head and neck squamous cell carcinoma. The second approach seeks to leverage tumour hypoxia as a tumour-specific address for hypoxia-activated prodrugs. These prodrugs are selectively activated by reductases under hypoxia to release cytotoxins, which in some instances may diffuse to kill surrounding oxic tumour tissue. A number of these hypoxia-activated prodrugs have been examined in clinical trial and the merits and shortcomings of recent examples are discussed. There has been an evolution from delivering DNA-interactive cytotoxins to molecularly targeted agents. Efforts to implement these strategies clinically continue today, but success has been elusive. Several issues have been identified that compromised these clinical campaigns. A failure to consider the extravascular transport and the micropharmacokinetic properties of the prodrugs has reduced efficacy. One key element for these 'targeted' approaches is the need to co-develop biomarkers to identify appropriate patients. Hypoxia-activated prodrugs require biomarkers for hypoxia, but also for appropriate activating reductases in tumours, as well as markers of intrinsic sensitivity to the released drug. The field is still evolving and changes in radiation delivery and the impact of immune-oncology will provide fertile ground for future innovation.
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Affiliation(s)
- R K Jackson
- Auckland Cancer Society Research Centre, School of Medical Sciences, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - L P Liew
- Auckland Cancer Society Research Centre, School of Medical Sciences, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
| | - M P Hay
- Auckland Cancer Society Research Centre, School of Medical Sciences, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand.
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10
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Sarkar U, Hillebrand R, Johnson KM, Cummings AH, Phung NL, Rajapakse A, Zhou H, Willis JR, Barnes CL, Gates KS. Application of Suzuki-Miyaura and Buchwald-Hartwig Cross-coupling Reactions to the Preparation of Substituted 1,2,4-Benzotriazine 1-Oxides Related to the Antitumor Agent Tirapazamine. J Heterocycl Chem 2017; 54:155-160. [PMID: 28439141 DOI: 10.1002/jhet.2559] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Many 1,2,4-benzotriazine 1,4-dioxides display the ability to selectively kill the oxygen-poor cells found in solid tumors. As a result, there is a desire for synthetic routes that afford access to substituted 1,2,4-benzotriazine 1-oxides that can be used as direct precursors in the synthesis of 1,2,4-benzotriazine 1,4-dioxides. Here we describe the use of Suzuki-Miyaura and Buchwald-Hartwig cross-coupling reactions for the construction of various 1,2,4-benzotriazine 1-oxide analogs bearing substituents at the 3-, 6-, and 7-positions.
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Affiliation(s)
- Ujjal Sarkar
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211
| | - Roman Hillebrand
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211
| | - Kevin M Johnson
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211
| | - Andrea H Cummings
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211
| | - Ngoc Linh Phung
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211
| | - Anuruddha Rajapakse
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211
| | - Haiying Zhou
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211
| | - Jordan R Willis
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211
| | - Charles L Barnes
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211
| | - Kent S Gates
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211.,University of Missouri, Department of Biochemistry, 125 Chemistry Building, Columbia, MO 65211
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11
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Patel A, Sant S. Hypoxic tumor microenvironment: Opportunities to develop targeted therapies. Biotechnol Adv 2016; 34:803-812. [PMID: 27143654 PMCID: PMC4947437 DOI: 10.1016/j.biotechadv.2016.04.005] [Citation(s) in RCA: 135] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 04/13/2016] [Accepted: 04/28/2016] [Indexed: 01/18/2023]
Abstract
In recent years, there has been great progress in the understanding of tumor biology and its surrounding microenvironment. Solid tumors create regions with low oxygen levels, generally termed as hypoxic regions. These hypoxic areas offer a tremendous opportunity to develop targeted therapies. Hypoxia is not a random by-product of the cellular milieu due to uncontrolled tumor growth; rather it is a constantly evolving participant in overall tumor growth and fate. This article reviews current trends and recent advances in drug therapies and delivery systems targeting hypoxia in the tumor microenvironment. In the first part, we give an account of important physicochemical changes and signaling pathways activated in the hypoxic microenvironment. This is then followed by various treatment strategies including hypoxia-sensitive signaling pathways and approaches to develop hypoxia-targeted drug delivery systems.
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Affiliation(s)
- Akhil Patel
- Department of Pharmaceutical Sciences, University of Pittsburgh School of Pharmacy, United States
| | - Shilpa Sant
- Department of Pharmaceutical Sciences, University of Pittsburgh School of Pharmacy, United States; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261, United States; McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15261, United States.
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12
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Quiñones JL, Demple B. When DNA repair goes wrong: BER-generated DNA-protein crosslinks to oxidative lesions. DNA Repair (Amst) 2016; 44:103-109. [PMID: 27264558 PMCID: PMC6420214 DOI: 10.1016/j.dnarep.2016.05.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Free radicals generate an array of DNA lesions affecting all parts of the molecule. The damage to deoxyribose receives less attention than base damage, even though the former accounts for ∼20% of the total. Oxidative deoxyribose fragments (e.g., 3'-phosphoglycolate esters) are removed by the Ape1 AP endonuclease and other enzymes in mammalian cells to enable DNA repair synthesis. Oxidized abasic sites are initially incised by Ape1, thus recruiting these lesions into base excision repair (BER) pathways. Lesions such as 2-deoxypentos-4-ulose can be removed by conventional (single-nucleotide) BER, which proceeds through a covalent Schiff base intermediate with DNA polymerase β (Polβ) that is resolved by hydrolysis. In contrast, the lesion 2-deoxyribonolactone (dL) must be processed by multinucleotide ("long-patch") BER: attempted repair via the single-nucleotide pathway leads to a dead-end, covalent complex with Polβ cross- linked to the DNA by an amide bond. We recently detected these stable DNA-protein crosslinks (DPC) between Polβ and dL in intact cells. The features of the DPC formation in vivo are exactly in keeping with the mechanistic properties seen in vitro: Polβ-DPC are formed by oxidative agents in line with their ability to form the dL lesion; they are not formed by non-oxidative agents; DPC formation absolutely requires the active-site lysine-72 that attacks the 5'-deoxyribose; and DPC formation depends on Ape1 to incise the dL lesion first. The Polβ-DPC are rapidly processed in vivo, the signal disappearing with a half-life of 15-30min in both mouse and human cells. This removal is blocked by inhibiting the proteasome, which leads to the accumulation of ubiquitin associated with the Polβ-DPC. While other proteins (e.g., topoisomerases) also form DPC under these conditions, 60-70% of the trapped ubiquitin depends on Polβ. The mechanism of ubiquitin targeting to Polβ-DPC, the subsequent processing of the expected 5'-peptidyl-dL, and the biological consequences of unrepaired DPC are important to assess. Many other lyase enzymes that attack dL can also be trapped in DPC, so the processing mechanisms may apply quite broadly.
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Affiliation(s)
- Jason Luis Quiñones
- Stony Brook University School of Medicine, Department of Pharmacological Sciences, Stony Brook, NY, 11794, USA
| | - Bruce Demple
- Stony Brook University School of Medicine, Department of Pharmacological Sciences, Stony Brook, NY, 11794, USA.
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Cheng G, Sa W, Cao C, Guo L, Hao H, Liu Z, Wang X, Yuan Z. Quinoxaline 1,4-di-N-Oxides: Biological Activities and Mechanisms of Actions. Front Pharmacol 2016; 7:64. [PMID: 27047380 PMCID: PMC4800186 DOI: 10.3389/fphar.2016.00064] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 03/07/2016] [Indexed: 11/29/2022] Open
Abstract
Quinoxaline 1,4-di-N-oxides (QdNOs) have manifold biological properties, including antimicrobial, antitumoral, antitrypanosomal and antiinflammatory/antioxidant activities. These diverse activities endow them broad applications and prospects in human and veterinary medicines. As QdNOs arouse widespread interest, the evaluation of their medicinal chemistry is still in progress. In the meantime, adverse effects have been reported in some of the QdNO derivatives. For example, genotoxicity and bacterial resistance have been found in QdNO antibacterial growth promoters, conferring urgent need for discovery of new QdNO drugs. However, the modes of actions of QdNOs are not fully understood, hindering the development and innovation of these promising compounds. Here, QdNOs are categorized based on the activities and usages, among which the antimicrobial activities are consist of antibacterial, antimycobacterial and anticandida activities, and the antiprotozoal activities include antitrypanosomal, antimalarial, antitrichomonas, and antiamoebic activities. The structure-activity relationship and the mode of actions of each type of activity of QdNOs are summarized, and the toxicity and the underlying mechanisms are also discussed, providing insight for the future research and development of these fascinating compounds.
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Affiliation(s)
- Guyue Cheng
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural UniversityWuhan, China; College of Veterinary Medicine, Huazhong Agricultural UniversityWuhan, China
| | - Wei Sa
- College of Veterinary Medicine, Huazhong Agricultural University Wuhan, China
| | - Chen Cao
- College of Veterinary Medicine, Huazhong Agricultural University Wuhan, China
| | - Liangliang Guo
- College of Veterinary Medicine, Huazhong Agricultural University Wuhan, China
| | - Haihong Hao
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural UniversityWuhan, China; College of Veterinary Medicine, Huazhong Agricultural UniversityWuhan, China
| | - Zhenli Liu
- College of Veterinary Medicine, Huazhong Agricultural UniversityWuhan, China; National Reference Laboratory of Veterinary Drug Residues and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural UniversityWuhan, China
| | - Xu Wang
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural UniversityWuhan, China; College of Veterinary Medicine, Huazhong Agricultural UniversityWuhan, China
| | - Zonghui Yuan
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural UniversityWuhan, China; College of Veterinary Medicine, Huazhong Agricultural UniversityWuhan, China; National Reference Laboratory of Veterinary Drug Residues and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural UniversityWuhan, China
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14
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Enzyme mechanism-based, oxidative DNA-protein cross-links formed with DNA polymerase β in vivo. Proc Natl Acad Sci U S A 2015; 112:8602-7. [PMID: 26124145 DOI: 10.1073/pnas.1501101112] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Free radical attack on the C1' position of DNA deoxyribose generates the oxidized abasic (AP) site 2-deoxyribonolactone (dL). Upon encountering dL, AP lyase enzymes such as DNA polymerase β (Polβ) form dead-end, covalent intermediates in vitro during attempted DNA repair. However, the conditions that lead to the in vivo formation of such DNA-protein cross-links (DPC), and their impact on cellular functions, have remained unknown. We adapted an immuno-slot blot approach to detect oxidative Polβ-DPC in vivo. Treatment of mammalian cells with genotoxic oxidants that generate dL in DNA led to the formation of Polβ-DPC in vivo. In a dose-dependent fashion, Polβ-DPC were detected in MDA-MB-231 human cells treated with the antitumor drug tirapazamine (TPZ; much more Polβ-DPC under 1% O2 than under 21% O2) and even more robustly with the "chemical nuclease" 1,10-copper-ortho-phenanthroline, Cu(OP)2. Mouse embryonic fibroblasts challenged with TPZ or Cu(OP)2 also incurred Polβ-DPC. Nonoxidative agents did not generate Polβ-DPC. The cross-linking in vivo was clearly a result of the base excision DNA repair pathway: oxidative Polβ-DPC depended on the Ape1 AP endonuclease, which generates the Polβ lyase substrate, and they required the essential lysine-72 in the Polβ lyase active site. Oxidative Polβ-DPC had an unexpectedly short half-life (∼ 30 min) in both human and mouse cells, and their removal was dependent on the proteasome. Proteasome inhibition under Cu(OP)2 treatment was significantly more cytotoxic to cells expressing wild-type Polβ than to cells with the lyase-defective form. That observation underscores the genotoxic potential of oxidative Polβ-DPC and the biological pressure to repair them.
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15
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Zhou D, He S, Cong Y, Xie Z, Chen X, Jing X, Huang Y. A polymer–(multifunctional single-drug) conjugate for combination therapy. J Mater Chem B 2015; 3:4913-4921. [DOI: 10.1039/c5tb00576k] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A single-drug integrating three different drug functions (platinum, azidyl radical and DMC) and two types of therapies (chemotherapy and radiation therapy) was synthesized and attached onto a carrier to prepare a polymer–(multifunctional single-drug) conjugate.
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Affiliation(s)
- Dongfang Zhou
- State Key Laboratory of Polymer Physics and Chemistry
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
- P. R. China
| | - Shasha He
- State Key Laboratory of Polymer Physics and Chemistry
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
- P. R. China
| | - Yuwei Cong
- State Key Laboratory of Polymer Physics and Chemistry
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
- P. R. China
| | - Zhigang Xie
- State Key Laboratory of Polymer Physics and Chemistry
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
- P. R. China
| | - Xuesi Chen
- Key Laboratory of Polymer Ecomaterials
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun 130022
- P. R. China
| | - Xiabin Jing
- State Key Laboratory of Polymer Physics and Chemistry
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
- P. R. China
| | - Yubin Huang
- State Key Laboratory of Polymer Physics and Chemistry
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
- P. R. China
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16
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Johnson K, Parsons ZD, Barnes CL, Gates KS. Toward hypoxia-selective DNA-alkylating agents built by grafting nitrogen mustards onto the bioreductively activated, hypoxia-selective DNA-oxidizing agent 3-amino-1,2,4-benzotriazine 1,4-dioxide (tirapazamine). J Org Chem 2014; 79:7520-31. [PMID: 25029663 PMCID: PMC4136725 DOI: 10.1021/jo501252p] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Indexed: 12/14/2022]
Abstract
Tirapazamine (3-amino-1,2,4-benzotriazine 1,4-dioxide) is a heterocyclic di-N-oxide that undergoes enzymatic deoxygenation selectively in the oxygen-poor (hypoxic) cells found in solid tumors to generate a mono-N-oxide metabolite. This work explored the idea that the electronic changes resulting from the metabolic deoxygenation of tirapazamine analogues might be exploited to activate a DNA-alkylating species selectively in hypoxic tissue. Toward this end, tirapazamine analogues bearing nitrogen mustard units were prepared. In the case of the tirapazamine analogue 18a bearing a nitrogen mustard unit at the 6-position, it was found that removal of the 4-oxide from the parent di-N-oxide to generate the mono-N-oxide analogue 17a did indeed cause a substantial increase in reactivity of the mustard unit, as measured by hydrolysis rates and DNA-alkylation yields. Hammett sigma values were measured to quantitatively assess the magnitude of the electronic changes induced by metabolic deoxygenation of the 3-amino-1,2,4-benzotriazine 1,4-dioxide heterocycle. The results provide evidence that the 1,2,4-benzotiazine 1,4-dioxide unit can serve as an oxygen-sensing prodrug platform for the selective unmasking of bioactive agents in hypoxic cells.
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Affiliation(s)
- Kevin
M. Johnson
- Departments of Chemistry and Biochemistry, University of Missouri, 125 Chemistry Building, Columbia, Missouri 65211, United
States
| | - Zachary D. Parsons
- Departments of Chemistry and Biochemistry, University of Missouri, 125 Chemistry Building, Columbia, Missouri 65211, United
States
| | - Charles L. Barnes
- Departments of Chemistry and Biochemistry, University of Missouri, 125 Chemistry Building, Columbia, Missouri 65211, United
States
| | - Kent S. Gates
- Departments of Chemistry and Biochemistry, University of Missouri, 125 Chemistry Building, Columbia, Missouri 65211, United
States
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17
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Li LH, Wu P, Lee JY, Li PR, Hsieh WY, Ho CC, Ho CL, Chen WJ, Wang CC, Yen MY, Yang SM, Chen HW. Hinokitiol induces DNA damage and autophagy followed by cell cycle arrest and senescence in gefitinib-resistant lung adenocarcinoma cells. PLoS One 2014; 9:e104203. [PMID: 25105411 PMCID: PMC4126702 DOI: 10.1371/journal.pone.0104203] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2014] [Accepted: 07/07/2014] [Indexed: 12/28/2022] Open
Abstract
Despite good initial responses, drug resistance and disease recurrence remain major issues for lung adenocarcinoma patients with epidermal growth factor receptor (EGFR) mutations taking EGFR-tyrosine kinase inhibitors (TKI). To discover new strategies to overcome this issue, we investigated 40 essential oils from plants indigenous to Taiwan as alternative treatments for a wide range of illnesses. Here, we found that hinokitiol, a natural monoterpenoid from the heartwood of Calocedrus formosana, exhibited potent anticancer effects. In this study, we demonstrated that hinokitiol inhibited the proliferation and colony formation ability of lung adenocarcinoma cells as well as the EGFR-TKI-resistant lines PC9-IR and H1975. Transcriptomic analysis and pathway prediction algorithms indicated that the main implicated pathways included DNA damage, autophagy, and cell cycle. Further investigations confirmed that in lung cancer cells, hinokitiol inhibited cell proliferation by inducing the p53-independent DNA damage response, autophagy (not apoptosis), S-phase cell cycle arrest, and senescence. Furthermore, hinokitiol inhibited the growth of xenograft tumors in association with DNA damage and autophagy but exhibited fewer effects on lung stromal fibroblasts. In summary, we demonstrated novel mechanisms by which hinokitiol, an essential oil extract, acted as a promising anticancer agent to overcome EGFR-TKI resistance in lung cancer cells via inducing DNA damage, autophagy, cell cycle arrest, and senescence in vitro and in vivo.
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Affiliation(s)
- Lan-Hui Li
- Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan
- Department of Laboratory, Kunming Branch, Taipei City Hospital, Taipei, Taiwan
| | - Ping Wu
- Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Jen-Yi Lee
- Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Pei-Rong Li
- Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Wan-Yu Hsieh
- Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Chao-Chi Ho
- Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University Medical College, Taipei, Taiwan
| | - Chen-Lung Ho
- Division of Wood Cellulose, Taiwan Forestry Research Institute, Taipei, Taiwan
| | - Wan-Jiun Chen
- Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan
- Graduate Institute of Oncology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Chien-Chun Wang
- Division of Infectious Diseases, Kunming Branch, Taipei City Hospital, Taipei, Taiwan
| | - Muh-Yong Yen
- Division of Infectious Diseases, Kunming Branch, Taipei City Hospital, Taipei, Taiwan
- Department of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Shun-Min Yang
- Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Huei-Wen Chen
- Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan
- * E-mail:
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18
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Chen W, Balakrishnan K, Kuang Y, Han Y, Fu M, Gandhi V, Peng X. Reactive oxygen species (ROS) inducible DNA cross-linking agents and their effect on cancer cells and normal lymphocytes. J Med Chem 2014; 57:4498-510. [PMID: 24801734 PMCID: PMC4133937 DOI: 10.1021/jm401349g] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Reducing host toxicity is one of the main challenges of cancer chemotherapy. Many tumor cells contain high levels of ROS that make them distinctively different from normal cells. We report a series of ROS-activated aromatic nitrogen mustards that selectively kill chronic lymphocytic leukemia (CLL) over normal lymphocytes. These agents showed powerful DNA cross-linking abilities when coupled with H2O2, one of the most common ROS in cancer cells, whereas little DNA cross-linking was detected without H2O2. Consistent with chemistry observation, in vitro cytotoxicity assay demonstrated that these agents induced 40-80% apoptosis in primary leukemic lymphocytes isolated from CLL patients but less than 25% cell death to normal lymphocytes from healthy donors. The IC50 for the most potent compound (2) was ~5 μM in CLL cells, while the IC50 was not achieved in normal lymphocytes. Collectively, these data provide utility and selectivity of these agents that will inspire further and effective applications.
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Affiliation(s)
- Wenbing Chen
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee , 3210 N. Cramer Street, Milwaukee, Wisconsin 53211, United States
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19
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Lin SC, Liao WL, Lee JC, Tsai SJ. Hypoxia-regulated gene network in drug resistance and cancer progression. Exp Biol Med (Maywood) 2014; 239:779-792. [PMID: 24812122 DOI: 10.1177/1535370214532755] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Hypoxia is a common phenomenon of solid tumors and contributes to aggressive phenotype and treatment failure. Hypoxia-inducible factor (HIF), a versatile transcription factor that regulates more than 5% of total human genes, not only plays important roles in controlling physiological processes, but is also a crucial mediator in hypoxia-induced tumor progression and chemoresistance. Overexpression of HIF-1α is detected in a wide spectrum of cancers via different kinds of mechanisms, including reduced oxygen concentration, loss-of-function of tumor suppressor gene, activating mutation of oncogenes, and hyperactivation of protein kinase signaling pathways. HIF-regulated genes involve in many pathological processes such as metabolic switch, drug efflux, angiogenesis, cell proliferation, and anti-apoptosis, which ultimately leads to increased tumor growth and drug resistance. Due to the common failure of classic chemotherapeutic agents in treating hypoxic cancers, novel strategies have been developed to target tumors under hypoxic conditions including inhibition of HIF activity and administration of bioreductive drugs. These new strategies may provide more effective and specific methods in targeting hypoxic tumors.
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Affiliation(s)
- Shao-Chieh Lin
- Department of Surgery, College of Medicine, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan
| | - Wan-Lin Liao
- Department of Physiology, College of Medicine, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan
| | - Jenq-Chang Lee
- Department of Surgery, College of Medicine, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan
| | - Shaw-Jenq Tsai
- Department of Physiology, College of Medicine, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan
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20
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Anderson RF, Yadav P, Patel D, Reynisson J, Tipparaju SR, Guise CP, Patterson AV, Denny WA, Maroz A, Shinde SS, Hay MP. Characterisation of radicals formed by the triazine 1,4-dioxide hypoxia-activated prodrug, SN30000. Org Biomol Chem 2014; 12:3386-92. [PMID: 24737463 DOI: 10.1039/c4ob00236a] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The radical species underlying the activity of the bioreductive anticancer prodrug, SN30000, have been identified by electron paramagnetic resonance and pulse radiolysis techniques. Spin-trapping experiments indicate both an aryl-type radical and an oxidising radical, trapped as a carbon-centred radical, are formed from the protonated radical anion of SN30000. The carbon-centred radical, produced upon the one-electron oxidation of the 2-electron reduced metabolite of SN30000, oxidises 2-deoxyribose, a model for the site of damage on DNA which leads to double strand breaks. Calculations using density functional theory support the assignments made.
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Affiliation(s)
- Robert F Anderson
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
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21
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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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22
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Shen X, Rajapakse A, Gallazzi F, Junnotula V, Fuchs-Knotts T, Glaser R, Gates KS. Isotopic labeling experiments that elucidate the mechanism of DNA strand cleavage by the hypoxia-selective antitumor agent 1,2,4-benzotriazine 1,4-di-N-oxide. Chem Res Toxicol 2013; 27:111-8. [PMID: 24328261 DOI: 10.1021/tx400356y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The 1,2,4-benzotriazine 1,4-dioxides are an important class of potential anticancer drugs that selectively kill the low-oxygen (hypoxic) cells found in solid tumors. These compounds undergo intracellular one-electron enzymatic reduction to yield an oxygen-sensitive drug radical intermediate that partitions forward, under hypoxic conditions, to generate a highly reactive secondary radical that causes cell killing DNA damage. Here, we characterized bioreductively activated, hypoxia-selective DNA-strand cleavage by 1,2,4-benzotriazine 1,4-dioxide. We found that one-electron enzymatic activation of 1,2,4-benzotriazine 1,4-dioxide under hypoxic conditions in the presence of the deuterium atom donor methanol-d4 produced nondeuterated mono-N-oxide metabolites. This and the results of other isotopic labeling studies provided evidence against the generation of atom-abstracting drug radical intermediates and are consistent with a DNA-damage mechanism involving the release of hydroxyl radical from enzymatically activated 1,2,4-benzotriazine 1,4-dioxides.
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Affiliation(s)
- Xiulong Shen
- Department of Chemistry, University of Missouri , 125 Chemistry Building, Columbia, Missouri 65211, United States
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23
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Transferring oxygen isotopes to 1,2,4-benzotriazine 1-oxides forming the corresponding 1,4-dioxides by using the HOF·CH3CN complex. Tetrahedron 2012. [DOI: 10.1016/j.tet.2012.08.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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24
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Rajapakse A, Gates KS. Hypoxia-selective, enzymatic conversion of 6-nitroquinoline into a fluorescent helicene: pyrido[3,2-f]quinolino[6,5-c]cinnoline 3-oxide. J Org Chem 2012; 77:3531-7. [PMID: 22417220 DOI: 10.1021/jo3004748] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Regions of low oxygen concentration (hypoxia) occur in both normal human physiology and under pathophysiological conditions. Fluorescent probes for the direct imaging of cellular hypoxia could be useful tools that complement radiochemical imaging and immunohistochemical staining methods. In this work, we set out to characterize the hypoxia-selective enzymatic metabolism of a simple nitroaryl probe, 6-nitroquinoline (1). We envisioned that this compound might undergo hypoxia-selective, bioreductive conversion to the fluorescent product, 6-aminoquinoline (2). The probe 1 was, indeed, converted to a fluorescent product selectively under hypoxic conditions by the one-electron reducing enzyme NADPH:cytochrome P450 reductase. However, inspection of the fluorescence spectrum and LC-MS analysis of the reaction mixture revealed that the expected product 2 was not formed. Rather, the 63-fold increase in fluorescence emission at 445 nm resulting from the hypoxic metabolism of 1 was due to formation of the azoxy-helicene product, pyrido[3,2-f]quinolino[6,5-c]cinnoline 3-oxide (4). The generation of 4 involves an unusual biaryl bond formation under reductive conditions. The mechanism of this process remains uncertain but could proceed via combination of a nitroaryl radical anion with a neutral nitrosoaryl radical, followed by tautomerization and intramolecular condensation between the resulting hydroxylamine and nitroso functional groups. Bioreductive metabolism of nitroaryl compounds represents a promising strategy for the selective delivery of cytotoxic agents and fluorescent markers to hypoxic tissue, but the results described here provide an important glimpse of the chemical complexity that can be associated with the enzymatic one-electron reduction of nitroaryl compounds.
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Affiliation(s)
- Anuruddha Rajapakse
- Department of Chemistry, University of Missouri, 125 Chemistry Building, Columbia, Missouri 65211, USA
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25
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Yin J, Glaser R, Gates KS. On the reaction mechanism of tirapazamine reduction chemistry: unimolecular N-OH homolysis, stepwise dehydration, or triazene ring-opening. Chem Res Toxicol 2012; 25:634-45. [PMID: 22390168 DOI: 10.1021/tx200546u] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The initial steps of the activation of tirapazamine (TPZ, 1, 3-amino-1,2,4-benzotriazine 1,4-N,N-dioxide) under hypoxic conditions consist of the one-electron reduction of 1 to radical anion 2 and the protonation of 2 at O(N4) or O(N1) to form neutral radicals 3 and 4, respectively. There are some questions, however, as to whether radicals 3 and/or 4 will then undergo N-OH homolyses 3 → 5 + ·OH and 4 → 6 + ·OH or, alternatively, whether 3 and/or 4 may react by dehydration and form aminyl radicals via 3 → 11 + H(2)O and 4 → 12 + H(2)O or phenyl radicals via 3 → 17 + H(2)O. These outcomes might depend on the chemistry after the homolysis of 3 and/or 4, that is, dehydration may be the result of a two-step sequence that involves N-OH homolysis and formation of ·OH aggregates of 5 and 6 followed by H-abstraction within the ·OH aggregates to form hydrates of aminyls 11 and 12 or of phenyl 17. We studied these processes with configuration interaction theory, perturbation theory, and density functional theory. All stationary structures of OH aggregates of 5 and 6, of H(2)O aggregates of 11, 12, and 17, and of the transition state structures for H-abstraction were located and characterized by vibrational analysis and with methods of electron and spin-density analysis. The doublet radical 17 is a normal spin-polarized radical, whereas the doublet radicals 11 and 12 feature quartet instabilities. The computed reaction energies and activation barriers allow for dehydration in principle, but the productivity of all of these channels should be low for kinetic and dynamic reasons. With a view to plausible scenarios for the generation of latent aryl radical species without dehydration, we scanned the potential energy surfaces of 2-4 as a function of the (O)N1-Y (Y = C5a, N2) and (O)N4-Z (Z = C4a, C3) bond lengths. The elongation of any one of these bonds by 0.5 Å requires less than 25 kcal/mol, and this finding strongly suggests the possibility of bimolecular reactions of the spin-trap molecules with 2-4 concomitant with triazene ring-opening.
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Affiliation(s)
- Jian Yin
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA
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26
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Yin J, Glaser R, Gates KS. Electron and spin-density analysis of tirapazamine reduction chemistry. Chem Res Toxicol 2012; 25:620-33. [PMID: 22390194 DOI: 10.1021/tx2005458] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Tirapazamine (TPZ, 1, 3-amino-1,2,4-benzotriazine 1,4-N,N-dioxide), the radical anion 2 formed by one-electron reduction of 1, and neutral radicals 3 and 4 formed by protonation of 2 at O(N4) or O(N1), respectively, and their N-OH homolyses 3 → 5 + ·OH and 4 → 6 + ·OH have been studied with configuration interaction theory, perturbation theory, and density functional theory. A comprehensive comparative analysis is presented of structures and electronic structures and with focus on the development of an understanding of the spin-density distributions of the radical species. The skeletons of radicals 3 and 4 are distinctly nonplanar, several stereoisomeric structures are discussed, and there exists an intrinsic preference for 3 over 4. The N-oxides 1, 5, and 6 have closed-shell singlet ground states and low-lying, singlet biradical (SP-1, SP-6) or biradicaloid (SP-5) excited states. The doublet radicals 2, 3, and 4 are heavily spin-polarized. Most of the spin density of the doublet radicals 2, 3, and 4 is located in one (N,O)-region, and in particular, 3 and 4 are not C3-centered radicals. Significant amounts of spin density occur in both rings in the singlet biradical(oid) excited states of 1, 5, and 6. The dipole moment of the N2-C3(X) bond is large, and the nature of X provides a powerful handle to modulate the N2-C3 bond polarity with opposite effects on the two NO regions. Our studies show very low proton affinities of radical anion 2 and suggest that the pK(a) of radical [2+H] might be lower than 6. Implications are discussed regarding the formation of hydroxyl from 3 and/or 4, regarding the ability of 5 and 6 to react with carbon-centered radicals in a manner that ultimately leads to oxygen transfer, and regarding the interpretation of the EPR spectra of reduced TPZ species and of their spin-trap adducts.
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Affiliation(s)
- Jian Yin
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA
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27
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Hunter FW, Wang J, Patel R, Hsu HL, Hickey AJR, Hay MP, Wilson WR. Homologous recombination repair-dependent cytotoxicity of the benzotriazine di-N-oxide CEN-209: comparison with other hypoxia-activated prodrugs. Biochem Pharmacol 2011; 83:574-85. [PMID: 22182429 DOI: 10.1016/j.bcp.2011.12.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Revised: 11/29/2011] [Accepted: 12/01/2011] [Indexed: 11/30/2022]
Abstract
CEN-209 (SN30000) is a second-generation benzotriazine di-N-oxide currently in advanced preclinical development as a hypoxia-activated prodrug (HAP). Herein we describe the DNA repair-, hypoxia- and one-electron reductase-dependence of CEN-209 cytotoxicity. We deployed mutant CHO cell lines to generate DNA repair profiles for CEN-209, and compared the profiles with those for other HAPs. Hypoxic selectivity of CEN-209 was significantly greater than PR-104A and the nitro-chloromethylbenzindoline (nCBI/SN29428) and comparable to tirapazamine and TH-302. CEN-209 was selective for homologous recombination (HR) repair-deficient cells (Rad51d⁻/⁻), but less so than nitrogen mustard prodrugs TH-302 and PR-104A. Further, DNA repair profiles for CEN-209 differed under oxic and hypoxic conditions, with oxic cytotoxicity more dependent on HR. This feature was conserved across all three members of the benzotriazine di-N-oxide class examined (tirapazamine, CEN-209 and CEN-309/SN29751). Enhancing one-electron reduction of CEN-209 by forced expression of a soluble form of NADPH:cytochrome P450 oxidoreductase (sPOR) increased CEN-209 cytotoxicity more markedly under oxic than hypoxic conditions. Comparison of oxygen consumption, H₂O₂ production and metabolism of CEN-209 to the corresponding 1-oxide and nor-oxide reduced metabolites suggested that enhanced oxic cytotoxicity in cells with high one-electron reductase activity is due to futile redox cycling. This study supports the hypothesis that both oxic and hypoxic cell killing by CEN-209 is mechanistically analogous to tirapazamine and is dependent on oxidative DNA damage repaired via multiple pathways. However, HAPs that generate DNA interstrand cross-links, such as TH-302 and PR-104, may be more suitable than benzotriazine di-N-oxides for exploiting reported HR repair defects in hypoxic tumour cells.
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Affiliation(s)
- Francis W Hunter
- Auckland Cancer Society Research Centre, University of Auckland, Private Bag 92019, Auckland, New Zealand
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28
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Chowdhury G, Sarkar U, Pullen S, Wilson WR, Rajapakse A, Fuchs-Knotts T, Gates KS. DNA strand cleavage by the phenazine di-N-oxide natural product myxin under both aerobic and anaerobic conditions. Chem Res Toxicol 2011; 25:197-206. [PMID: 22084973 DOI: 10.1021/tx2004213] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Heterocyclic N-oxides are an interesting class of antitumor agents that selectively kill the hypoxic cells found in solid tumors. The hypoxia-selective activity of the lead compound in this class, tirapazamine, stems from its ability to undergo intracellular one-electron reduction to an oxygen-sensitive drug radical intermediate. In the presence of molecular oxygen, the radical intermediate is back-oxidized to the parent molecule. Under hypoxic conditions, the extended lifetime of the drug radical intermediate enables its conversion to a highly cytotoxic DNA-damaging intermediate via a "deoxygenative" mechanism involving the loss of oxygen from one of its N-oxide groups. The natural product myxin is a phenazine di-N-oxide that displays potent antibiotic activity against a variety of organisms under aerobic conditions. In light of the current view of heterocyclic N-oxides as agents that selectively operate under hypoxic conditions, it is striking that myxin was identified from Sorangium extracts based upon its antibiotic properties under aerobic conditions. Therefore, we set out to examine the molecular mechanisms underlying the biological activity of myxin. We find that myxin causes bioreductively activated, radical-mediated DNA strand cleavage under both aerobic and anaerobic conditions. Our evidence indicates that strand cleavage occurs via a deoxygenative metabolism. We show that myxin displays potent cytotoxicity against the human colorectal cancer cell line HCT-116 under both aerobic and anaerobic conditions that is comparable to the cell-killing properties of tirapazamine under anaerobic conditions. This work sheds light on the processes by which the naturally occurring aromatic N-oxide myxin gains its potent antibiotic properties under aerobic conditions. Furthermore, these studies highlight the general potential for aromatic N-oxides to undergo highly cytotoxic deoxygenative metabolism following enzymatic one-electron reduction under aerobic conditions.
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Affiliation(s)
- Goutam Chowdhury
- Department of Chemistry, University of Missouri-Columbia, 125 Chemistry Building, Columbia, Missouri 65211, United States
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29
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Abstract
Hypoxia is a feature of most tumours, albeit with variable incidence and severity within a given patient population. It is a negative prognostic and predictive factor owing to its multiple contributions to chemoresistance, radioresistance, angiogenesis, vasculogenesis, invasiveness, metastasis, resistance to cell death, altered metabolism and genomic instability. Given its central role in tumour progression and resistance to therapy, tumour hypoxia might well be considered the best validated target that has yet to be exploited in oncology. However, despite an explosion of information on hypoxia, there are still major questions to be addressed if the long-standing goal of exploiting tumour hypoxia is to be realized. Here, we review the two main approaches, namely bioreductive prodrugs and inhibitors of molecular targets upon which hypoxic cell survival depends. We address the particular challenges and opportunities these overlapping strategies present, and discuss the central importance of emerging diagnostic tools for patient stratification in targeting hypoxia.
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Affiliation(s)
- William R Wilson
- Auckland Cancer Society Research Centre, The University of Auckland, Auckland, New Zealand.
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30
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Sarkar U, Glaser R, Parsons ZD, Barnes CL, Gates KS. Synthesis, Crystal Structure, and Rotational Energy Profile of 3-Cyclopropyl-1,2,4-benzotriazine 1,4-Di-N-oxide. JOURNAL OF CHEMICAL CRYSTALLOGRAPHY 2010; 40:624-629. [PMID: 22294856 PMCID: PMC3268128 DOI: 10.1007/s10870-010-9707-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
1,2,4-Benzotriazine 1,4-di-N-oxides are potent antitumor drug candidates that undergo in vivo bioreduction leading to selective DNA damage in the low oxygen (hypoxic) cells found in tumors. Tirapazamine (TPZ) is the lead compound in this family. Here we report on the synthesis, crystal structure, and conformational analysis of a new analog, 3-cyclopropyl-1,2,4-benzotriazine 1,4-di-N-oxide (3). Compound 3 (C(10)H(10)N(3)O(2)) crystallized in the monoclinic space group C2/c. Unit cell parameters for 3: a = 16.6306 (12), b = 7.799 (5), c = 16.0113 (11) Å, α = 90, β = 119.0440 (10), γ = 90, and z = 8.
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Affiliation(s)
- Ujjal Sarkar
- Department of Chemistry, University of Missouri-Columbia, Columbia, MO 65211
| | - Rainer Glaser
- Department of Chemistry, University of Missouri-Columbia, Columbia, MO 65211
| | - Zack D. Parsons
- Department of Chemistry, University of Missouri-Columbia, Columbia, MO 65211
| | - Charles L. Barnes
- Department of Chemistry, University of Missouri-Columbia, Columbia, MO 65211
| | - Kent S. Gates
- Department of Chemistry, University of Missouri-Columbia, Columbia, MO 65211
- Department of Biochemistry, University of Missouri-Columbia, Columbia, MO 65211
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31
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Denny WA. Hypoxia-activated prodrugs in cancer therapy: progress to the clinic. Future Oncol 2010; 6:419-28. [PMID: 20222798 DOI: 10.2217/fon.10.1] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The hypoxic cells common in solid tumors (because of their inefficient blood supply) limit the effectiveness of radiotherapy and many cytotoxic drugs. Nontoxic prodrugs that generate active species in hypoxic tissue by selective bioreduction have long been explored, and the first examples, representing a variety of different chemistries, have now reached advanced clinical trials. In the process, a great deal has been learnt about the properties that such drugs require to be successful, notably, efficient extravascular diffusion, appropriate reduction chemistry and kinetics, and an effective biological profile of the activated species, including a good bystander effect. The critical importance of prodrug diffusion and techniques to quantify this have assisted the development of models to predict the killing of tumor cells, which promises to help accelerate new drug evaluation. A cell cycle-independent mechanism of killing by the released cytotoxin is also a potential advantage, although it is likely that much of the killing will be when out-of-cycle hypoxic cells reoxygenate and resume division.
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Affiliation(s)
- William A Denny
- Auckland Cancer Society Research Centre, The University of Auckland, New Zealand.
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32
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Shinde SS, Maroz A, Hay MP, Patterson AV, Denny WA, Anderson RF. Characterization of radicals formed following enzymatic reduction of 3-substituted analogues of the hypoxia-selective cytotoxin 3-amino-1,2,4-benzotriazine 1,4-dioxide (tirapazamine). J Am Chem Soc 2010; 132:2591-9. [PMID: 20141134 DOI: 10.1021/ja908689f] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The mechanism by which the 1,2,4-benzotriazine 1,4-dioxide (BTO) class of bioreductive hypoxia-selective prodrugs (HSPs) form reactive radicals that kill cancer cells has been investigated by steady-state radiolysis, pulse radiolysis (PR), electron paramagnetic resonance (EPR), and density functional theory (DFT) calculations. Tirapazamine (TPZ, 3-amino BTO, 1) and a series of 3-substituted analogues, -H (2), -methyl (3), -ethyl (4), -methoxy (5), -ethoxymethoxy (6), and -phenyl (7), were reduced in aqueous solution under anaerobic steady-state radiolysis conditions, and their radicals were found to remove the substrates by short chain reactions of different lengths in the presence of formate ions. Multiple carbon-centered radical intermediates, produced upon anaerobic incubation of the compounds with cytochrome P(450) reductase enriched microsomes, were trapped by N-tert-butyl-alpha-phenylnitrone and observed using EPR. The highly oxidizing oxymethyl radical, from compound 5, was identified, and experimental spectra obtained for compounds 1, 2, 3, and 7 were well simulated after the inclusion of aryl radicals. The identification of a range of oxidizing radicals in the metabolism of the BTO compounds gives a new insight into the mechanism by which these HSPs can cause a wide variety of damage to biological targets such as DNA.
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Affiliation(s)
- Sujata S Shinde
- Department of Chemistry and Auckland Cancer Society Research Centre, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
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Junnotula V, Rajapakse A, Arbillaga L, de Cerain AL, Solano B, Villar R, Monge A, Gates KS. DNA strand cleaving properties and hypoxia-selective cytotoxicity of 7-chloro-2-thienylcarbonyl-3-trifluoromethylquinoxaline 1,4-dioxide. Bioorg Med Chem 2010; 18:3125-32. [PMID: 20371184 PMCID: PMC3268132 DOI: 10.1016/j.bmc.2010.03.042] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2010] [Revised: 03/15/2010] [Accepted: 03/16/2010] [Indexed: 11/28/2022]
Abstract
The heterocyclic N-oxide, 3-amino-1,2,4-benzotriazine 1,4-dioxide (tirapazamine, 1), shows promising antitumor activity in preclinical studies, but there is a continuing need to explore new compounds in this general structural category. In the work described here, we examined the properties of 7-chloro-2-thienylcarbonyl-3-trifluoromethylquinoxaline 1,4-dioxide (9h). We find that 9h causes redox-activated, hypoxia-selective DNA cleavage that mirrors the lead compound, tirapazamine, in both mechanism and potency. Furthermore, we find that 9h displays hypoxia-selective cytotoxicity against human cancer cell lines.
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Gates KS. An overview of chemical processes that damage cellular DNA: spontaneous hydrolysis, alkylation, and reactions with radicals. Chem Res Toxicol 2010; 22:1747-60. [PMID: 19757819 DOI: 10.1021/tx900242k] [Citation(s) in RCA: 348] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The sequence of heterocyclic bases on the interior of the DNA double helix constitutes the genetic code that drives the operation of all living organisms. With this said, it is not surprising that chemical modification of cellular DNA can have profound biological consequences. Therefore, the organic chemistry of DNA damage is fundamentally important to diverse fields including medicinal chemistry, toxicology, and biotechnology. This review is designed to provide a brief overview of the common types of chemical reactions that lead to DNA damage under physiological conditions.
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Affiliation(s)
- Kent S Gates
- Departments of Chemistry and Biochemistry, University of Missouri-Columbia, 125 Chemistry Building, Columbia, Missouri 65211.
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35
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Shinde SS, Hay MP, Patterson AV, Denny WA, Anderson RF. Spin trapping of radicals other than the *OH radical upon reduction of the anticancer agent tirapazamine by cytochrome P450 reductase. J Am Chem Soc 2009; 131:14220-1. [PMID: 19772319 DOI: 10.1021/ja906860a] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The radical species produced following one-electron reduction of tirapazamine (3-amino-1,2,4-benzotriazine 1,4-dioxide, TPZ) by cytochrome P(450) reductase-enriched microsomes have been investigated using electron paramagnetic resonance (EPR) spectroscopy. Spin trapping with 5,5'-dimethylpyrroline 1-N-oxide (DMPO) gave a composite spectrum of a carbon-centered radical and the well-known DMPO-OH adduct. Using (17)O-labeled water resulted in a change in the EPR spectrum to that of DMPO-(17)OH, indicating that this radical species is formed with solvent involvement and not from release of a (*)OH radical from one-electron-reduced TPZ. Furthermore, using the closely related spin trap 5-diethoxyphosphoryl-5-methylpyrroline N-oxide (DEPMPO), which is less prone to oxidation than DMPO, gave only a carbon-centered radical spectrum without any involvement of a (*)OH radical. Reduction of a more soluble analogue of TPZ, in redox equilibrium with its 1-oxide derivative, led to spin trapping of both a carbon-centered radical and a nitrogen-centered radical by N-tert-butyl-alpha-phenylnitrone (PBN). The multicentered nature of this nitrogen-centered radical spectrum provides support for the formation of a benzotriazinyl radical following one-electron reduction of this class of bioreductive drug.
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Affiliation(s)
- Sujata S Shinde
- Department of Chemistry and Auckland Cancer Society Research Centre, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
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36
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Chowdhury G, Guengerich FP. Tandem mass spectrometry-based detection of c4'-oxidized abasic sites at specific positions in DNA fragments. Chem Res Toxicol 2009; 22:1310-9. [PMID: 19496605 DOI: 10.1021/tx900115z] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Oxidative damage to DNA has been linked to aging, cancer, and other biological processes. Reactive oxygen species and various antitumor agents including bleomycin and ionizing radiation have been shown to cause oxidative DNA sugar damage. Detection of DNA lesions is important for understanding the toxicological or therapeutic consequences associated with such agents. C4'-oxidized abasic sites (C4-AP) are produced by the antitumor drug bleomycin and ionizing radiation. The currently available methods for the detection of C4-AP cannot provide both structural and sequence information. We have developed an LC-ESI-MS-based approach for specific detection and mapping of C4-AP from a mixture of lesions. We show using Fe-bleomycin-damaged DNA that C4-AP can be detected at cytosine and thymine sites by direct MS analysis. Our results reveal that collision-induced dissociation of C4-AP-containing oligonucleotides results in preferential fragmentation at C4-AP sites with the formation of the unique a* ions (18 amu more than the a-B ions) that allow mapping of the C4-AP sites. Various chemical modification strategies (e.g., reduction with NaBH4 and NaBD4 and derivatization with methoxyamine and hydrazine, followed by LC-MS analysis) were also used for unambiguous detection of C4-AP sites. Finally, we show that the methods described here can detect the presence of C4-AP at specific sites in a complex sample such as hydroxyl radical-damaged DNA. The LC-MS approach was also used for the simultaneous detection of the other C4'-oxidation end product, 3'-phosphoglycolate, at a specific site in hydroxyl radical-damaged DNA. Thus, LC-MS provides a rapid and direct approach for the detection and mapping of oxidative DNA lesions.
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Affiliation(s)
- Goutam Chowdhury
- Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, 638 Robinson Research Building, 2200 Pierce Avenue, Nashville, Tennessee 37232-0146, USA
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Roginskaya M, Razskazovskiy Y. Selective radiation-induced generation of 2-deoxyribonolactone lesions in DNA mediated by aromatic iodonium derivatives. Radiat Res 2009; 171:342-8. [PMID: 19267561 DOI: 10.1667/rr1574.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
2-Deoxyribonolactone lesions were identified as major products of radiation damage to DNA mediated by o,o'-diphenyleneiodonium cations in a hydroxyl radical-scavenging environment. The highest selectivity toward deoxyribonolactone formation (up to 86% of all sugar-phosphate damages) and the overall reaction efficiency (up to 40% of all radiation-generated intermediates converted into products) was displayed by derivatives with positively charged (2-aminoethylthio)acetylamino and (2-aminoethylamino)acetylamino side chains. The reaction can be useful for random single-step incorporation of deoxyribonolactone lesions into single- and double-stranded oligonucleotides and highly polymerized DNA directly in commonly used buffers (PBS, phosphate, Tris-HCl, etc.) at room temperature. In combination with HPLC separation, this technique can serve as a source of short (<6 mer) sequences containing deoxyribonolactone lesions at known positions.
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Affiliation(s)
- Marina Roginskaya
- Department of Physics and Astronomy, East Tennessee State University, Johnson City, Tennessee 37614, USA
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38
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Junnotula V, Sarkar U, Sinha S, Gates KS. Initiation of DNA strand cleavage by 1,2,4-benzotriazine 1,4-dioxide antitumor agents: mechanistic insight from studies of 3-methyl-1,2,4-benzotriazine 1,4-dioxide. J Am Chem Soc 2009; 131:1015-24. [PMID: 19117394 PMCID: PMC2819123 DOI: 10.1021/ja8049645] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The antitumor agent 3-amino-1,2,4-benzotriazine 1,4-dioxide (tirapazamine, TPZ, 1) gains medicinal activity through its ability to selectively damage DNA in the hypoxic cells found inside solid tumors. This occurs via one-electron enzymatic reduction of TPZ to yield an oxygen-sensitive drug radical (2) that leads to oxidatively generated DNA damage under hypoxic conditions. Two possible mechanisms have been considered to account for oxidatively generated DNA damage by TPZ. First, homolysis of the N-OH bond in 2 may yield the well-known DNA-damaging agent, hydroxyl radical. Alternatively, it has been suggested that elimination of water from 2 generates a benzotriazinyl radical (4) as the ultimate DNA-damaging species. In the studies described here, the TPZ analogue 3-methyl-1,2,4-benzotriazine 1,4-dioxide (5) was employed as a tool to probe the mechanism of DNA damage within this new class of antitumor drugs. Initially, it was demonstrated that 5 causes redox-activated, hypoxia-selective oxidation of DNA and small organic substrates in a manner that is completely analogous to TPZ. This suggests that 5 and TPZ damage DNA by the same chemical mechanism. Importantly, the methyl substituent in 5 provides a means for assessing whether the putative benzotriazinyl intermediate 7 is generated following one-electron reduction. Two complementary isotopic labeling experiments provide evidence against the formation of the benzotriazinyl radical intermediate. Rather, a mechanism involving the release of hydroxyl radical from the activated drug radical intermediates can explain the DNA-cleaving properties of this class of antitumor drug candidates.
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Affiliation(s)
- Venkatraman Junnotula
- University of Missouri–Columbia, Departments of Chemistry and Biochemistry, 125 Chemistry Building, Columbia, MO 65211
| | - Ujjal Sarkar
- University of Missouri–Columbia, Departments of Chemistry and Biochemistry, 125 Chemistry Building, Columbia, MO 65211
| | - Sarmistha Sinha
- University of Missouri–Columbia, Departments of Chemistry and Biochemistry, 125 Chemistry Building, Columbia, MO 65211
| | - Kent S. Gates
- University of Missouri–Columbia, Departments of Chemistry and Biochemistry, 125 Chemistry Building, Columbia, MO 65211
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39
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Son MY, Jun HI, Lee KG, Demple B, Sung JS. Biochemical evaluation of genotoxic biomarkers for 2-deoxyribonolactone-mediated cross-link formation with histones. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2009; 72:1311-1317. [PMID: 20077202 DOI: 10.1080/15287390903212402] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Numerous environmental carcinogens involve radical formation interacting with DNA to produce 2-deoxyribonolactone (dL), a major type of oxidized abasic site, implicated in DNA strand breaks, mutagenesis, and formation of covalent DNA-protein cross-links (DPC). Studies showed major dL-specific DPC occurred due to reactions with DNA polymerase beta (Polbeta) dependent on native conformation, while other DPC formed involved nonenzymatic reactions of DNA binding proteins with dL lesions. Polbeta appeared to play a major role in alleviating the cytotoxic effects of neocarzinostatin, which was used as a dL-producing agent. When a duplex DNA containing a dL at a site-specific position was incubated with purified histones, DPC were formed between dL and each histone protein, including H1, H2A, H2B, H3, and H4. Comparative kinetic analysis of DPC formation with histones and Polbeta revealed two distinct mechanisms of dL-mediated DPC formation. The rate of DPC formation with Polbeta was approximately two orders of magnitude higher than that with various histone proteins. These results indicate that catalytic activity of Polbeta mediates rapid DPC formation between dL and this DNA repair enzyme, whereas nonenzymatic reactions of dL with histones form DPC more slowly. The abundance of histones and their constant interaction with DNA may nevertheless yield significant levels of DPC with dL, as biomarkers of dL-induced cytotoxicity. Overall, data suggest that occurrence of dL-mediated DPC with histones may contribute to the genotoxic effects of dL in DNA.
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Affiliation(s)
- Mi-Young Son
- Department of Life Science, Dongguk University, Seoul, Korea
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40
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Hay MP, Hicks KO, Pchalek K, Lee HH, Blaser A, Pruijn FB, Anderson RF, Shinde SS, Wilson WR, Denny WA. Tricyclic [1,2,4]triazine 1,4-dioxides as hypoxia selective cytotoxins. J Med Chem 2008; 51:6853-65. [PMID: 18847185 DOI: 10.1021/jm800967h] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A series of novel tricyclic triazine-di- N-oxides (TTOs) related to tirapazamine have been designed and prepared. A wide range of structural arrangements with cycloalkyl, oxygen-, and nitrogen-containing saturated rings fused to the triazine core, coupled with various side chains linked to either hemisphere, resulted in TTO analogues that displayed hypoxia-selective cytotoxicity in vitro. Optimal rates of hypoxic metabolism and tissue diffusion coefficients were achieved with fused cycloalkyl rings in combination with both the 3-aminoalkyl or 3-alkyl substituents linked to weakly basic soluble amines. The selection was further refined using pharmacokinetic/pharmacodynamic model predictions of the in vivo hypoxic potency (AUC req) and selectivity (HCD) with 12 TTO analogues predicted to be active in vivo, subject to the achievement of adequate plasma pharmacokinetics.
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Affiliation(s)
- Michael P Hay
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand.
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41
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Lavaggi ML, Cabrera M, González M, Cerecetto H. Differential Enzymatic Reductions Governing the Differential Hypoxia-Selective Cytotoxicities of Phenazine 5,10-Dioxides. Chem Res Toxicol 2008; 21:1900-6. [DOI: 10.1021/tx800199v] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- María Laura Lavaggi
- Departamento de Química Orgánica, Facultad de Química-Facultad de Ciencias, Universidad de la República, Iguá 4225, 11400 Montevideo, Uruguay
| | - Mauricio Cabrera
- Departamento de Química Orgánica, Facultad de Química-Facultad de Ciencias, Universidad de la República, Iguá 4225, 11400 Montevideo, Uruguay
| | - Mercedes González
- Departamento de Química Orgánica, Facultad de Química-Facultad de Ciencias, Universidad de la República, Iguá 4225, 11400 Montevideo, Uruguay
| | - Hugo Cerecetto
- Departamento de Química Orgánica, Facultad de Química-Facultad de Ciencias, Universidad de la República, Iguá 4225, 11400 Montevideo, Uruguay
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42
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Pruijn FB, Patel K, Hay MP, Wilson WR, Hicks KO. Prediction of Tumour Tissue Diffusion Coefficients of Hypoxia-Activated Prodrugs from Physicochemical Parameters. Aust J Chem 2008. [DOI: 10.1071/ch08240] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The therapeutic activity of anticancer agents depends critically on their ability to penetrate through tumour tissue to reach their target cells, a requirement that is especially important for hypoxia-activated prodrugs. Here we use multicellular layers (MCL) grown in vitro from HT29 colon carcinoma cells to measure tissue diffusion coefficients (Dmcl) of 67 structurally diverse benzotriazine di-N-oxides (analogues of the hypoxia-activated prodrug tirapazamine) plus four miscellaneous compounds. An algorithm was developed to predict Dmcl from physicochemical parameters (molecular weight, octanol/water partition coefficient at pH 7.4, number of hydrogen bond donors and acceptors); the fitted multivariate relationship had an explained variance (R2) of 0.907 and predictive power (Q2) of 0.879. Using a subset of nine compounds tested as a single cassette, the algorithm was shown to apply, with some adjustment of coefficients, to MCLs from three other tumour cell lines with differing cell packing densities (SiHa, HCT8-Ea, and HCT8-Ra). The demonstrated relationships provide tools for optimizing extravascular transport of anticancer agents during lead optimization.
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