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Abstract
The activation of the cGAS-STING pathway has tremendous potential to improve anti-tumor immunity by generating type I interferons. In recent decades, we have witnessed that producing dsDNA upon various stimuli is an initiative factor, triggering the cGAS-SING pathway for a defensive host. The understanding of both intracellular cascade reaction and the changes of molecular components gains insight into type I IFNs and adaptive immunity. Based on the immunological study, the STING-cGAS pathway is coupled to cancer biotherapy. The most challenging problem is the limited therapeutic effect. Therefore, people view 5, 6-dimethylxanthenone-4-acetic acid, cyclic dinucleotides and various derivative as cGAS-STING pathway agonists. Even so, these agonists have flaws in decreasing biotherapeutic efficacy. Subsequently, we exploited agonist delivery systems (nanocarriers, microparticles and hydrogels). The article will discuss the activation of the cGAS-STING pathway and underlying mechanisms, with an introduction of cGAS-STING agonists, related clinical trials and agonist delivery systems.
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Daei Farshchi Adli A, Jahanban-Esfahlan R, Seidi K, Samandari-Rad S, Zarghami N. An overview on Vadimezan (DMXAA): The vascular disrupting agent. Chem Biol Drug Des 2018; 91:996-1006. [DOI: 10.1111/cbdd.13166] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Revised: 11/29/2017] [Accepted: 12/17/2017] [Indexed: 01/02/2023]
Affiliation(s)
- Amir Daei Farshchi Adli
- Department of Medical Biotechnology; Faculty of Advanced Medical Sciences; Tabriz University of Medical Sciences; Tabriz Iran
| | - Rana Jahanban-Esfahlan
- Department of Medical Biotechnology; Faculty of Advanced Medical Sciences; Tabriz University of Medical Sciences; Tabriz Iran
- Student Research Committee; Tabriz University of Medical Sciences; Tabriz Iran
| | - Khaled Seidi
- Department of Medical Biotechnology; Faculty of Advanced Medical Sciences; Tabriz University of Medical Sciences; Tabriz Iran
| | - Sonia Samandari-Rad
- Faculty of Medicine; Physiology Research Center; Tehran University of Medical Sciences; Tehran Iran
- Department of Physiology; Faculty of Medicine; Tehran University of Medical Sciences; Tehran Iran
| | - Nosratollah Zarghami
- Department of Medical Biotechnology; Faculty of Advanced Medical Sciences; Tabriz University of Medical Sciences; Tabriz Iran
- Department of Clinical Biochemistry and Laboratory Medicine; Faculty of Medicine; Tabriz University of Medical Sciences; Tabriz Iran
- Iranian National Science Foundation; Tehran Iran
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Baguley BC, Ding Q, Richardson E. Preliminary Evidence That High-Dose Vitamin C has a Vascular Disrupting Action in Mice. Front Oncol 2014; 4:310. [PMID: 25414833 PMCID: PMC4220656 DOI: 10.3389/fonc.2014.00310] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 10/18/2014] [Indexed: 12/20/2022] Open
Abstract
High intravenous doses of vitamin C (ascorbic acid) have been reported to benefit cancer patients, but the data are controversial and there is incomplete knowledge of what physiological mechanisms might be involved in any response. Vitamin C is taken up efficiently by cells expressing SVCT2 transporters and since vascular endothelial cells express SVCT2, we explored the hypothesis that administration of high-dose vitamin C (up to 5 g/kg) to mice might affect vascular endothelial function. A single administration of vitamin C to mice induced time- and dose-dependent increases in plasma concentrations of the serotonin metabolite 5-hydroxyindole acetic acid (5-HIAA), a marker for vascular disrupting effects. Responses were comparable to those for the tumor vascular disrupting agents, vadimezan and fosbretabulin. High-dose vitamin C administration decreased tumor serotonin concentrations, consistent with the release of serotonin from platelets and its metabolism to 5-HIAA. High-dose vitamin C also significantly increased the degree of hemorrhagic necrosis in tumors removed after 24 h, and significantly decreased tumor volume after 2 days. However, the effect on tumor growth was temporary. The results support the concept that vitamin C at high dose increases endothelial permeability, allowing platelets to escape and release serotonin. Plasma 5-HIAA concentrations could provide a pharmacodynamic biomarker for vitamin C effects in clinical studies.
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Affiliation(s)
- Bruce C Baguley
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland , Auckland , New Zealand
| | - Qi Ding
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland , Auckland , New Zealand
| | - Emma Richardson
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland , Auckland , New Zealand
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DMXAA (Vadimezan, ASA404) is a multi-kinase inhibitor targeting VEGFR2 in particular. Clin Sci (Lond) 2012; 122:449-57. [PMID: 22142330 DOI: 10.1042/cs20110412] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The flavone acetic acid derivative DMXAA [5,6-dimethylXAA (xanthenone-4-acetic acid), Vadimezan, ASA404] is a drug that displayed vascular-disrupting activity and induced haemorrhagic necrosis and tumour regression in pre-clinical animal models. Both immune-mediated and non-immune-mediated effects contributed to the tumour regression. The vascular disruption was less in human tumours, with immune-mediated effects being less prominent, but nonetheless DMXAA showed promising effects in Phase II clinical trials in non-small-cell lung cancer. However, these effects were not replicated in Phase III clinical trials. It has been difficult to understand the differences between the pre-clinical findings and the later clinical trials as the molecular targets for the agent have never been clearly established. To investigate the mechanism of action, we sought to determine whether DMXAA might target protein kinases. We found that, at concentrations achieved in blood during clinical trials, DMXAA has inhibitory effects against several kinases, with most potent effects being on members of the VEGFR (vascular endothelial growth factor receptor) tyrosine kinase family. Some analogues of DMXAA were even more effective inhibitors of these kinases, in particular 2-MeXAA (2-methylXAA) and 6-MeXAA (6-methylXAA). The inhibitory effects were greatest against VEGFR2 and, consistent with this, we found that DMXAA, 2-MeXAA and 6-MeXAA were able to block angiogenesis in zebrafish embryos and also inhibit VEGFR2 signalling in HUVECs (human umbilical vein endothelial cells). Taken together, these results indicate that at least part of the effects of DMXAA are due to it acting as a multi-kinase inhibitor and that the anti-VEGFR activity in particular may contribute to the non-immune-mediated effects of DMXAA on the vasculature.
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Mass balance, excretion and metabolism of [14C] ASA404 in cancer patients in a phase I trial. Cancer Chemother Pharmacol 2012; 69:1145-54. [DOI: 10.1007/s00280-011-1809-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2011] [Accepted: 12/14/2011] [Indexed: 10/14/2022]
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Jameson MB, Head M. Pharmacokinetic evaluation of vadimezan (ASA404, 5,6-dimethylxanthenone-4-acetic acid, DMXAA). Expert Opin Drug Metab Toxicol 2011; 7:1315-26. [DOI: 10.1517/17425255.2011.614389] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Baguley BC, McKeage MJ. ASA404: a tumor vascular-disrupting agent with broad potential for cancer therapy. Future Oncol 2011; 6:1537-43. [PMID: 21062153 DOI: 10.2217/fon.10.122] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
ASA404 (5,6-dimethylxanthenone-4-acetic acid) was developed as an analogue of flavone acetic acid and found to induce hemorrhagic necrosis of experimental tumors. ASA404 simultaneously targets at least two cell types - vascular endothelial cells and macrophages - within the tumor microenvironment. In murine tumors, ASA404 induces coordinated decreases in tumor blood flow, increases in vascular permeability and increases in vascular endothelial apoptosis, all occurring within 1 h of administration. Over a slightly longer time scale, ASA404 induces an increase in tumor concentrations of TNF and a number of other cytokines. Phase I clinical trials confirmed its vascular effects in humans and Phase II trials demonstrated its activity in combination with the cytotoxic agents carboplatin and paclitaxel. While the molecular target of its action is not yet identified, current results suggest that ASA404 has the potential to augment the antitumor effects of other agents in cancer treatment. Studies of changes in tumor tissue following treatment with ASA404 either alone or combined and other agents will provide new insights into the dynamics of the tumor microenvironment.
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Affiliation(s)
- Bruce C Baguley
- Auckland Cancer Society Research Center, Faculty of Medical & Health Sciences, The University of Auckland, New Zealand.
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Yi H, Shin MJ, Cho SM, Lee DG, Cho K, Cho HJ, Shin SJ, Bartlett MG, Kim JS, Shin HC. Nonlinear toxicokinetics of enrofloxacin in rats. Arch Pharm Res 2010; 33:1851-7. [PMID: 21116789 DOI: 10.1007/s12272-010-1118-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Revised: 08/12/2010] [Accepted: 08/17/2010] [Indexed: 01/16/2023]
Abstract
The dose-dependent toxicokinetics of enrofloxacin were studied by administering various single subcutaneous doses (5, 10, 20, 40, 70, 100, 150, 200, 300 and 400 mg/kg) in male Sprague-Dawley rats. The blood samples were collected from the tail veins, and the plasma concentration of enrofloxacin was determined by an HPLC-fluorescence detection (FLD) method. The time-concentration profiles of enrofloxacin were well fitted by an one-compartmental model with first order elimination. The absorption half-lives (t₁(/)₂(abs)) ranged from 0.2-0.8 h, and the mean time to maximum plasma concentration (T(max)) ranged from 0.6-1.8 h. On the other hand, marked disproportionate increases of the area under the curve (AUC) and elimination half-lives (t₁(/)₂) were observed from the increase of the doses. This result indicates that the elimination of enrofloxacin has nonlinear pharmacokinetic properties with increasing doses. Therefore, we need to take into consideration the possible occurrence of side effects resulting from greater systemic exposure from high dose therapies.
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Affiliation(s)
- Hee Yi
- Department of Veterinary Pharmacology and Toxicology, Konkuk University, Seoul, Korea
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Ramírez J, Ratain MJ, Innocenti F. Uridine 5'-diphospho-glucuronosyltransferase genetic polymorphisms and response to cancer chemotherapy. Future Oncol 2010; 6:563-85. [PMID: 20373870 PMCID: PMC3102300 DOI: 10.2217/fon.10.17] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Pharmacogenetics aims to elucidate how genetic variation affects the efficacy and side effects of drugs, with the ultimate goal of personalizing medicine. Clinical studies of the genetic variation in the uridine 5'-diphosphoglucuronosyltransferase gene have demonstrated how reduced-function allele variants can predict the risk of severe toxicity and help identify cancer patients who could benefit from reduced-dose schedules or alternative chemotherapy. Candidate polymorphisms have also been identified in vitro, although the functional consequences of these variants still need to be tested in the clinical setting. Future approaches in uridine 5'-diphosphoglucuronosyltransferase pharmacogenetics include genetic testing prior to drug treatment, genotype-directed dose-escalation studies, study of genetic variation at the haplotype level and genome-wide studies.
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Affiliation(s)
- Jacqueline Ramírez
- Department of Medicine, The University of Chicago, 5841 S. Maryland Avenue, MC2115, Chicago, IL, USA 60637, Tel.: +1 773 834 2451, Fax: +1 773 702 9268,
| | - Mark J Ratain
- Department of Medicine, Committee on Clinical Pharmacology & Pharmacogenomics, Cancer Research Center, The University of Chicago, 5841 S. Maryland Avenue, MC2115, Chicago, IL, USA 60637, Tel.: +1 773 702 4400, Fax: +1 773 702 3969,
| | - Federico Innocenti
- Department of Medicine, Committee on Clinical Pharmacology & Pharmacogenomics, Cancer Research Center, The University of Chicago, 5841 S. Maryland Avenue, MC2115, Chicago, IL, USA 60637, Tel.: +1 773 834 2452, Fax: +1 773 702 9268,
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Head M, Jameson MB. The development of the tumor vascular-disrupting agent ASA404 (vadimezan, DMXAA): current status and future opportunities. Expert Opin Investig Drugs 2010; 19:295-304. [PMID: 20050824 DOI: 10.1517/13543780903540214] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
IMPORTANCE OF THE FIELD Targeting tumor vasculature with antiangiogenic agents improves outcomes achieved with chemotherapy in some cancers, but toxicity limits their applicability. Tumor vascular-disrupting agents (tumor-VDAs) induce an acute collapse in tumor vascular supply; ASA404 (vadimezan, 5,6-dimethylxanthenone-4-acetic acid [DMXAA]) is the tumor-VDA most advanced in clinical development. Recent randomized trials of ASA404 in combination with chemotherapy suggested a survival advantage in NSCLC comparable to that achieved with bevacizumab, but with little additional toxicity. Phase III trials in advanced NSCLC have completed accrual, and a review of this exciting agent is timely. AREAS COVERED IN THIS REVIEW This review focuses on the development of ASA404 to date, its mechanisms of action, the current body of clinical research and potential avenues for therapeutic use. It includes all completed clinical trials since it entered clinical testing in 1995 through to 2009. WHAT THE READER WILL GAIN This review will help the reader to understand why ASA404 is unique among tumor-VDAs; the clinical trial methodology required to evaluate such agents; and its remarkable potential clinical utility. TAKE HOME MESSAGE ASA404 is a tumor-VDA that offers considerable potential to improve outcomes in cancer patients in combination with existing treatments.
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Affiliation(s)
- Michelle Head
- Waikato Hospital, Regional Cancer Centre, Waikato Hospital, Private Bag 3200, Hamilton 3240, New Zealand
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Chen G, Horsman MR, Pedersen M, Pang Q, Stødkilde-jørgensen H. The effect of combretastatin A4 disodium phosphate and 5,6-dimethylxanthenone-4-acetic acid on water diffusion and blood perfusion in tumours. Acta Oncol 2008; 47:1071-6. [PMID: 18770061 DOI: 10.1080/02841860701769750] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
PURPOSE To evaluate the effect of the vascular disrupting drugs combretastatin A-4 disodium phosphate (CA4DP) and 5,6-dimethylxanthenone-4-acetic acid (DMXAA) on the intra/extracellular volume fraction of water and blood perfusion in tumours using MRI. METHODS AND MATERIALS Mice with C3H mammary carcinomas underwent repeated MRI T2-weighted imaging, water-diffusion and perfusion measurements before and up to 6-hours following CA4DP and DMXAA treatment. RESULTS CA4DP treatment caused an increase in water diffusion in those tumour areas that presented the lowest blood perfusion, however this appeared only after five hours. The blood perfusion in highly perfused tumour regions decreased immediately after administration of CA4DP. DMXAA treatment caused an early decrease in water diffusion in the low-perfused tumour segments and followed by a subsequent decrease in the remaining part of the tumour. The blood perfusion decreased early in all parts of the tumour. CONCLUSION The effect of CA4DP and DMXAA on tumour blood flow was comparable. The reduction in regional blood flow caused by CA4DP in the whole tumour segment occurred early, however, changes in ADC after DMXAA appeared more extended and earlier than after CA4DP treatment, especially in tumour areas already suffering from a low blood perfusion.
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Diagaradjane P, Shetty A, Wang JC, Elliott AM, Schwartz J, Shentu S, Park HC, Deorukhkar A, Stafford RJ, Cho SH, Tunnell JW, Hazle JD, Krishnan S. Modulation of in vivo tumor radiation response via gold nanoshell-mediated vascular-focused hyperthermia: characterizing an integrated antihypoxic and localized vascular disrupting targeting strategy. NANO LETTERS 2008; 8:1492-500. [PMID: 18412402 PMCID: PMC3952070 DOI: 10.1021/nl080496z] [Citation(s) in RCA: 146] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
We report noninvasive modulation of in vivo tumor radiation response using gold nanoshells. Mild-temperature hyperthermia generated by near-infrared illumination of gold nanoshell-laden tumors, noninvasively quantified by magnetic resonance temperature imaging, causes an early increase in tumor perfusion that reduces the hypoxic fraction of tumors. A subsequent radiation dose induces vascular disruption with extensive tumor necrosis. Gold nanoshells sequestered in the perivascular space mediate these two tumor vasculature-focused effects to improve radiation response of tumors. This novel integrated antihypoxic and localized vascular disrupting therapy can potentially be combined with other conventional antitumor therapies.
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Affiliation(s)
- Parmeswaran Diagaradjane
- Department of Experimental Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas
| | - Anil Shetty
- Department of Imaging Physics, The University of Texas M. D. Anderson Cancer Center, Houston, Texas
| | - James C. Wang
- Department of Experimental Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas
- Nanospectra Biosciences Inc. Houston, Texas
| | - Andrew M. Elliott
- Department of Imaging Physics, The University of Texas M. D. Anderson Cancer Center, Houston, Texas
| | | | - Shujun Shentu
- Department of Experimental Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas
| | - Hee C. Park
- Department of Experimental Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas
| | - Amit Deorukhkar
- Department of Experimental Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas
| | - R. Jason Stafford
- Department of Imaging Physics, The University of Texas M. D. Anderson Cancer Center, Houston, Texas
| | - Sang H. Cho
- Department of Radiation Physics, The University of Texas M. D. Anderson Cancer Center, Houston, Texas
| | - James W. Tunnell
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas
| | - John D. Hazle
- Department of Imaging Physics, The University of Texas M. D. Anderson Cancer Center, Houston, Texas
| | - Sunil Krishnan
- Department of Experimental Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas
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Li J, Jameson MB, Baguley BC, Pili R, Baker SD. Population Pharmacokinetic-Pharmacodynamic Model of the Vascular-Disrupting Agent 5,6-Dimethylxanthenone-4-Acetic Acid in Cancer Patients. Clin Cancer Res 2008; 14:2102-10. [DOI: 10.1158/1078-0432.ccr-07-1475] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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McKeage MJ. The potential of DMXAA (ASA404) in combination with docetaxel in advanced prostate cancer. Expert Opin Investig Drugs 2008; 17:23-9. [PMID: 18095916 DOI: 10.1517/13543784.17.1.23] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
5,6-Dimethylxanthenone-4-acetic acid (DMXAA) is a vascular disrupting agent that has demonstrated efficacy in combination with taxane-based chemotherapy in patients with advanced cancer. Complementary modes of action, a lack of pharmacokinetic interaction and distinct adverse effect profiles provide a strong rationale for combining these anticancer agents. In a Phase II trial in men with hormone refractory prostate cancer, DMXAA (ASA404) in combination with docetaxel achieved a prostate-specific antigen response in more patients than docetaxel therapy alone, and was generally well tolerated. Further clinical evaluation of this combination in this patient population is warranted.
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Affiliation(s)
- Mark J McKeage
- The University of Auckland, School of Medical Sciences, Department of Pharmacology and Clinical Pharmacology, Private Bag 92019, Auckland, New Zealand.
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Kwitniewski M, Juzeniene A, Glosnicka R, Moan J. Immunotherapy: a way to improve the therapeutic outcome of photodynamic therapy? Photochem Photobiol Sci 2008; 7:1011-7. [DOI: 10.1039/b806710d] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Kanthou C, Tozer GM. Selective destruction of the tumour vasculature by targeting the endothelial cytoskeleton. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/j.ddstr.2008.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Chung F, Liu J, Ching LM, Baguley BC. Consequences of increased vascular permeability induced by treatment of mice with 5,6-dimethylxanthenone-4-acetic acid (DMXAA) and thalidomide. Cancer Chemother Pharmacol 2007; 61:497-502. [PMID: 17473922 DOI: 10.1007/s00280-007-0495-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2006] [Accepted: 04/04/2007] [Indexed: 10/23/2022]
Abstract
PURPOSE 5,6-Dimethylxanthenone-4-acetic acid (DMXAA) (AS1404), a small-molecule vascular disrupting agent currently in clinical trial, increases vascular permeability and decreases blood flow in both murine and human tumours. DMXAA induces tumour necrosis factor (TNF) in mice and the effects on vascular permeability are hypothesised to result from both direct (DMXAA) and indirect (TNF) effects. Skin temperature decreases in mice treated with high doses of DMXAA, raising the question of whether host toxicity is mediated by the induction of increased vascular permeability in normal tissue. Thalidomide is an anti-inflammatory agent that potentiates the anti-tumour activity of DMXAA but decreases induction of TNF in plasma. We wished to determine how it potentiated the effects of DMXAA. METHODS Vascular permeability was measured in Colon 38 tumour and liver tissue by uptake of Evans Blue dye. Blood haematocrit and body temperature were also measured. RESULTS Tumour vascular permeability was increased following administration of DMXAA (25 mg/kg i.p.), minimally affected following thalidomide (100 mg/kg i.p.) but strongly increased following co-administration of both drugs. In contrast, dye uptake into liver tissue was decreased following administration of DMXAA, thalidomide or both drugs. Administration of DMXAA at a potentially toxic dose (35 mg/kg i.p. or 50 mg/kg orally) was found to decrease body temperature and to increase the blood haematocrit, while administration of thalidomide alone (100 mg/kg i.p.) had no effect. Co-administration of thalidomide potentiated the effects of DMXAA on both body temperature and haematocrit but surprisingly did not increase toxicity. CONCLUSIONS The results are consistent with the hypothesis that the host toxicity of high-dose DMXAA is mediated by effects on host vasculature. Co-administration of thalidomide increases the effective dose of DMXAA by reducing clearance but also, by inhibiting production of circulating TNF, reduces the host toxicity of DMXAA.
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Affiliation(s)
- Francisco Chung
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, New Zealand
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