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Castano AP, Demidova TN, Hamblin MR. Mechanisms in photodynamic therapy: part one-photosensitizers, photochemistry and cellular localization. Photodiagnosis Photodyn Ther 2014; 1:279-93. [PMID: 25048432 DOI: 10.1016/s1572-1000(05)00007-4] [Citation(s) in RCA: 1325] [Impact Index Per Article: 132.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2004] [Revised: 01/11/2005] [Accepted: 01/27/2005] [Indexed: 10/25/2022]
Abstract
The use of non-toxic dyes or photosensitizers (PS) in combination with harmless visible light that is known as photodynamic therapy (PDT) has been known for over a hundred years, but is only now becoming widely used. Originally developed as a tumor therapy, some of its most successful applications are for non-malignant disease. In a series of three reviews we will discuss the mechanisms that operate in the field of PDT. Part one discusses the recent explosion in discovery and chemical synthesis of new PS. Some guidelines on how to choose an ideal PS for a particular application are presented. The photochemistry and photophysics of PS and the two pathways known as Type I (radicals and reactive oxygen species) and Type II (singlet oxygen) photochemical processes are discussed. To carry out PDT effectively in vivo, it is necessary to ensure sufficient light reaches all the diseased tissue. This involves understanding how light travels within various tissues and the relative effects of absorption and scattering. The fact that most of the PS are also fluorescent allows various optical imaging and monitoring strategies to be combined with PDT. The most important factor governing the outcome of PDT is how the PS interacts with cells in the target tissue or tumor, and the key aspect of this interaction is the subcellular localization of the PS. Examples of PS that localize in mitochondria, lysosomes, endoplasmic reticulum, Golgi apparatus and plasma membranes are given. Finally the use of 5-aminolevulinic acid as a natural precursor of the heme biosynthetic pathway, stimulates accumulation of the PS protoporphyrin IX is described.
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Affiliation(s)
- Ana P Castano
- Wellman Center for Photomedicine, Massachusetts General Hospital, 40 Blossom Street, Bartlett 3, Boston, MA 02114, USA; Department of Dermatology, Harvard Medical School, USA
| | - Tatiana N Demidova
- Wellman Center for Photomedicine, Massachusetts General Hospital, 40 Blossom Street, Bartlett 3, Boston, MA 02114, USA; Department of Cellular, Molecular and Developmental Biology, Tufts University, USA
| | - Michael R Hamblin
- Wellman Center for Photomedicine, Massachusetts General Hospital, 40 Blossom Street, Bartlett 3, Boston, MA 02114, USA; Department of Dermatology, Harvard Medical School, USA
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2
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Ranyuk E, Lebel R, Bérubé-Lauzière Y, Klarskov K, Lecomte R, van Lier JE, Guérin B. 68Ga/DOTA- and 64Cu/NOTA-Phthalocyanine Conjugates as Fluorescent/PET Bimodal Imaging Probes. Bioconjug Chem 2013; 24:1624-33. [DOI: 10.1021/bc400257u] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
| | | | - Yves Bérubé-Lauzière
- Department
of Electrical and Computer Engineering, Université de Sherbrooke, 2500 boulevard Université, Sherbrooke, Québec, Canada J1K 2R1
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3
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Josefsen LB, Boyle RW. Unique diagnostic and therapeutic roles of porphyrins and phthalocyanines in photodynamic therapy, imaging and theranostics. Theranostics 2012; 2:916-66. [PMID: 23082103 PMCID: PMC3475217 DOI: 10.7150/thno.4571] [Citation(s) in RCA: 384] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Accepted: 08/10/2012] [Indexed: 02/07/2023] Open
Abstract
Porphyrinic molecules have a unique theranostic role in disease therapy; they have been used to image, detect and treat different forms of diseased tissue including age-related macular degeneration and a number of different cancer types. Current focus is on the clinical imaging of tumour tissue; targeted delivery of photosensitisers and the potential of photosensitisers in multimodal biomedical theranostic nanoplatforms. The roles of porphyrinic molecules in imaging and pdt, along with research into improving their selective uptake in diseased tissue and their utility in theranostic applications are highlighted in this Review.
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4
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OWENS JOHNW, ROBINS MARSHA. Phthalocyanine photophysics and photosensitizer efficiency on human embryonic lung fibroblasts. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1002/jpp.340] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This study correlates the photophysical properties of aluminum phthalocyanine tetrasulfonate (AlPcTs), zinc phthalocyanine tetrasulfonate (ZnPcTs), and phthalocyanine tetrasulfonate (PcTs) with their ability to kill human embryonic lung (HEL) cells. Photofrin, a proven anti-cancer drug, was used for comparison. The photophysical properties include fluorescence emission spectra, fluorescence quantum yields, singlet state and radiative lifetimes, quantum yield for triplet formation, and fluorescence rate constants. Results indicate that photodynamic efficacy correlates inversely with fluorescence quantum yield and fluorescence lifetime and directly with quantum yield for triplet formation.
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Affiliation(s)
- JOHN W. OWENS
- Department of Chemistry and Health Research Center, Southern University, Baton Rouge, LA 70813, USA
| | - MARSHA ROBINS
- Department of Chemistry and Health Research Center, Southern University, Baton Rouge, LA 70813, USA
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5
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Borshch VN, Andreeva ER, Kuz’min SG, Vozovikov IN. New medicines and approaches to treatment of atherosclerosis. RUSS J GEN CHEM+ 2012. [DOI: 10.1134/s1070363212030346] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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6
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Chen Z, Zhou S, Chen J, Deng Y, Luo Z, Chen H, Hamblin MR, Huang M. Pentalysine beta-carbonylphthalocyanine zinc: an effective tumor-targeting photosensitizer for photodynamic therapy. ChemMedChem 2010; 5:890-8. [PMID: 20458713 PMCID: PMC2935799 DOI: 10.1002/cmdc.201000042] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Indexed: 12/22/2022]
Abstract
Unsymmetrical phthalocyanine derivatives have been widely studied as photosensitizers for photodynamic therapy (PDT), targeting various tumor types. However, the preparation of unsymmetrical phthalocyanines is always a challenge due to the presence of many possible structural isomers. Herein we report a new unsymmetrical zinc phthalocyanine, pentalysine beta-carbonylphthalocyanine zinc (ZnPc-(Lys)(5)), that was prepared in large quantity and high purity. This is a water-soluble cationic photosensitizer and maintains a high quantum yield of singlet oxygen generation similar to that of unsubstituted zinc phthalocyanine (ZnPc). Compared with anionic ZnPc counterparts, ZnPc-(Lys)(5) shows a higher level cellular uptake and 20-fold higher phototoxicity toward tumor cells. Pharmacokinetics and PDT studies of ZnPc-(Lys)(5) in S180 tumor-bearing mice showed a high ratio of tumor versus skin retention and significant tumor inhibition. This new molecular framework will allow synthetic diversity in the number of lysine residues incorporated and will facilitate future QSAR studies.
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Affiliation(s)
- Zhuo Chen
- Graduate University of Chinese Academy of Sciences, 19 Yuquan Road, Shijingshan District, Beijing 100049 (China), Fax: (+86) 591-83714946
- China–Denmark Center for Proteases and Cancer, State Key Laboratory of Structural Chemistry, Division of Chemical Biology, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yang Qiao West Road, Fuzhou, Fujian 350002 (China)
| | - Shanyong Zhou
- China–Denmark Center for Proteases and Cancer, State Key Laboratory of Structural Chemistry, Division of Chemical Biology, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yang Qiao West Road, Fuzhou, Fujian 350002 (China)
| | - Jincan Chen
- China–Denmark Center for Proteases and Cancer, State Key Laboratory of Structural Chemistry, Division of Chemical Biology, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yang Qiao West Road, Fuzhou, Fujian 350002 (China)
| | - Yicai Deng
- Sun Yat-Sen University No. 1 Hospital, 58 Zhong Shan No. 2 Road, Guangzhou, Guangdong 510080 (China)
| | - Zhipu Luo
- Graduate University of Chinese Academy of Sciences, 19 Yuquan Road, Shijingshan District, Beijing 100049 (China), Fax: (+86) 591-83714946
- China–Denmark Center for Proteases and Cancer, State Key Laboratory of Structural Chemistry, Division of Chemical Biology, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yang Qiao West Road, Fuzhou, Fujian 350002 (China)
| | - Hongwei Chen
- Graduate University of Chinese Academy of Sciences, 19 Yuquan Road, Shijingshan District, Beijing 100049 (China), Fax: (+86) 591-83714946
- China–Denmark Center for Proteases and Cancer, State Key Laboratory of Structural Chemistry, Division of Chemical Biology, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yang Qiao West Road, Fuzhou, Fujian 350002 (China)
| | - Michael R. Hamblin
- Wellman Center for Photomedicine, Massachusetts General Hospital, 40 Blossom Street, Boston MA 02114 (USA)
- Department of Dermatology, Harvard Medical School, 55 Fruit Street, Boston, MA 02114 (USA)
- Harvard–MIT Division of Health Sciences and Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (USA)
| | - Mingdong Huang
- Graduate University of Chinese Academy of Sciences, 19 Yuquan Road, Shijingshan District, Beijing 100049 (China), Fax: (+86) 591-83714946
- China–Denmark Center for Proteases and Cancer, State Key Laboratory of Structural Chemistry, Division of Chemical Biology, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yang Qiao West Road, Fuzhou, Fujian 350002 (China)
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7
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Yumita N, Umemura SI. Sonodynamic antitumour effect of chloroaluminum phthalocyanine tetrasulfonate on murine solid tumour. J Pharm Pharmacol 2010; 56:85-90. [PMID: 14980005 DOI: 10.1211/0022357022412] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Abstract
The sonodynamically induced antitumour effect of chloroaluminum phthalocyanine tetrasulfonate (AlPcTS) was evaluated on subcutaneously implanted colon 26 carcinoma. A time of 24h after the administration of AlPcTS was chosen for the ultrasonic exposure, based on the analysis of the AlPcTS concentrations in the tumour, plasma, skin and muscle. The pharmacokinetic analysis showed much faster clearance of AlPcTS than photofrin II from the body, which can be an advantage in view of their potential adverse effects. At an AlPcTS dose not less than 2.5 mg kg−1 and at a free-field ultrasonic intensity not less than 3 W cm−2, the synergistic effect between AlPcTS administration and ultrasonic exposure on the tumour growth inhibition was significant. The ultrasonic intensity showed a relatively sharp threshold for the synergistic antitumour effect, which is typical for an ultrasonic effect mediated by acoustic cavitation. These results suggest that AlPcTS is a potential sonosensitizer for sonodynamic treatment of solid tumours.
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Affiliation(s)
- Nagahiko Yumita
- School of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan
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8
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Ben-Hur E, Nagelkerke JF, Dubbelman TM, Van Steveninck J. The Effect of Fluoride on Photodynamic-induced Fluorescence Changes of Aluminium Phthalocyanine in Chinese Hamster Cells. Int J Radiat Biol 2009; 61:767-72. [PMID: 1351525 DOI: 10.1080/09553009214551621] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Fluence-dependent changes in the fluorescence of aluminium phthalocyanine (AlPc) were measured in Chinese hamster ovary (CHO) cells using digital fluorescence microscopy of single cells and spectrofluorimetry of cell suspensions. During illumination the fluorescence initially increased and later progressively decreased. In the presence of fluoride, which protects against phototoxicity of AlPc by forming a fluoroaluminium complex, there was no initial increase in fluorescence: it decreased about 10 times faster than in the absence of fluoride. Qualitatively similar results were observed using single-cell fluorescence microscopy, which also showed the dye to be mostly localized in cytoplasmic organelles and membranes. The pattern of localization did not change during illumination. Concomitant assays of dye extracted from cells revealed little photodegradation that could not account for the fluorescence changes. The absorption spectra of AlPc-loaded cells showed some aggregation of the dye prior to light exposure. During illumination the dye was initially monomerized and subsequently progressively reaggregated. In the presence of fluoride no monomerization was seen, and the aggregation proceeded at a much faster rate. It is concluded that the fluorescence changes are not due to major relocalization of AlPc in the cells, but to light-induced monomerization followed by reaggregation. The protective effect of fluoride may be due to the enhanced aggregation rate, because aggregated dye molecules are photochemically inactive. Because D2(0) affects neither the initial enhanced fluorescence in the absence of fluoride nor the rapid decrease in its presence it appears that 1O2 is not involved in the photodynamic reactions leading to these changes.
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Affiliation(s)
- E Ben-Hur
- Nuclear Research Center-Negev, Beer-Sheva, Israel
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9
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Mitton D, Ackroyd R. A brief overview of photodynamic therapy in Europe. Photodiagnosis Photodyn Ther 2008; 5:103-11. [DOI: 10.1016/j.pdpdt.2008.04.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2008] [Revised: 04/22/2008] [Accepted: 04/23/2008] [Indexed: 10/21/2022]
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10
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Lee CC, Pouge BW, Strawbridge RR, Moodie KL, Bartholomew LR, Burke GC, Jack Hoopes P. Comparison of Photosensitizer (AlPcS2) Quantification Techniques: In Situ Fluorescence Microsampling Versus Tissue Chemical Extraction¶. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2001)0740453copaqt2.0.co2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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11
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Kessel D, Luguya R, Vicente MGH. Localization and Photodynamic Efficacy of Two Cationic Porphyrins Varying in Charge Distribution¶. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2003)0780431lapeot2.0.co2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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12
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Gomes ER, Almeida RD, Carvalho AP, Duarte CB. Nitric Oxide Modulates Tumor Cell Death Induced by Photodynamic Therapy Through a cGMP-dependent Mechanism¶. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2002)0760423nomtcd2.0.co2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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13
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Juzeniene A, Moan J. The history of PDT in Norway Part one: Identification of basic mechanisms of general PDT. Photodiagnosis Photodyn Ther 2006; 4:3-11. [PMID: 25047184 DOI: 10.1016/j.pdpdt.2006.11.002] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2006] [Revised: 10/12/2006] [Accepted: 11/08/2006] [Indexed: 12/01/2022]
Abstract
Photodynamic therapy (PDT) is now an established treatment of malignant and premalignant dysplasias. A number of first and second generation photosensitizers have been studied in Norway. The aim has been to improve PDT efficiency and applicability. Many critical details regarding the mechanisms of PDT were elucidated by researchers in Norway. In this review we focus on the most important findings related to these basic mechanisms, such as generation of singlet oxygen, estimations of its lifetime, the oxygen effect itself, the subcellular localization of photosensitizers with different properties, their photodegradation during PDT and their tumour selectivity.
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Affiliation(s)
- Asta Juzeniene
- Department of Radiation Biology, The Norwegian Radium Hospital, Montebello, N-0310 Oslo, Norway
| | - Johan Moan
- Department of Radiation Biology, The Norwegian Radium Hospital, Montebello, N-0310 Oslo, Norway; Institute of Physics, Oslo University, Blindern, 0316 Oslo, Norway
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14
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Tamosiūnas M, Bagdonas S, Didziapetriene J, Rotomskis R. Electroporation of transplantable tumour for the enhanced accumulation of photosensitizers. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2005; 81:67-75. [PMID: 16112584 DOI: 10.1016/j.jphotobiol.2005.05.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2005] [Revised: 05/17/2005] [Accepted: 05/17/2005] [Indexed: 10/25/2022]
Abstract
The aim of this study was to verify whether electroporation could increase the accumulation of the hydrophilic photosensitizers: aluminium phthalocyanine tetrasulphonate (AlPcS(4)) and chlorin e(6) (C e(6)) in tumour tissue. The experiment was performed in vivo using hybrid mice (C57Bl/CBA) bearing hepatoma A22 (MH-A22) tumours transplanted in the right haunch. The time dependence of the fluorescence intensity of administered photosensitizers was measured after the ordinary and electrically stimulated delivery. The obtained fluorescence spectroscopy results implied the tumour being affected by an electrical field in a way, which led to a higher accumulation of both photosensitizers (AlPcS(4) and C e(6)) in the periphery of the tumour and it superficial layer. Our pilot study suggests that electroporation could be considered as a useful procedure seeking for the more effective application of photodynamic tumour treatment.
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Affiliation(s)
- M Tamosiūnas
- Vilnius University, Laser Research Center, 10222 Vilnius, Lithuania
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15
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Juzenas P, Juzeniene A, Rotomskis R, Moan J. Spectroscopic evidence of monomeric aluminium phthalocyanine tetrasulphonate in aqueous solutions. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2005; 75:107-10. [PMID: 15246357 DOI: 10.1016/j.jphotobiol.2004.05.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2004] [Revised: 05/29/2004] [Accepted: 05/30/2004] [Indexed: 10/26/2022]
Abstract
Aqueous solutions of aluminium phthalocyanine tetrasulphonate (AlPcS(4)) were investigated by means of absorption and fluorescence spectroscopy. The absorption spectrum of AlPcS(4) is independent of concentration in a wide range (from 10(-8) to 10(-4) M). The fluorescence spectrum measured with a standard setup is strongly dependent on AlPcS(4) concentration, and the fluorescence maximum is gradually red-shifted with increasing concentration. Calculations that take into account reabsorption of fluorescence (inner-filter effect) fit the experimental observations at low concentrations (up to 10(-6) M). Disagreement between the calculations and spectra recorded at higher concentrations (above 10(-5) M) shows that the reabsorbed light may be reemitted as fluorescence. The influence of inner-filter effects on the spectral shape was demonstrated by the experiments where a fibre-optic front-face fluorescence setup was applied: Under such conditions the shape of the fluorescence spectra for a high concentration (10(-3) M) coincided with that of a low concentration (10(-8) M). In conclusion, the present spectroscopic results show that AlPcS(4) does not form aggregates and is a very stable compound in aqueous solutions.
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Affiliation(s)
- Petras Juzenas
- Institute for Cancer Research, Department of Radiation Biology, The Norwegian Radium Hospital, Oslo, Norway.
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Abstract
Photodynamic therapy (PDT) is a treatment that combines a photosensitizer with light to generate oxygen-dependent photochemical destruction of diseased tissue. This modality has been approved worldwide since 1993 for the treatment of several oncological and nononcological disorders. PDT continues to be interested in both preclinical and clinical research, with more than 500 publications each year during the past 5 years. This minireview focuses on the effects of PDT on tumor stroma. A tumor consists of two fundamental elements: parenchyma (neoplastic cells) and stroma. The stroma is composed of vasculature, cellular components, and intercellular matrix and is necessary for tumor growth. All the stromal components can be targeted by PDT. Although the exact mechanism of PDT is unknown, emerging evidence has indicated that effective PDT of tumor requires destruction of both parenchyma and stroma. Further, damage to subendothelial zone of vasculature, in addition to endothelium, also appears to be a crucial factor. The PDT-generated immune response as a way of vaccination for treatment and prevention of metastatic tumors remains to be exploited.
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Affiliation(s)
- Qian Peng
- Department of Pathology, The Norwegian Radium Hospital, University of Oslo, Oslo, Norway.
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17
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Bonneau S, Morlière P, Brault D. Dynamics of interactions of photosensitizers with lipoproteins and membrane-models: correlation with cellular incorporation and subcellular distribution. Biochem Pharmacol 2004; 68:1443-52. [PMID: 15345334 DOI: 10.1016/j.bcp.2004.06.014] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2004] [Accepted: 06/17/2004] [Indexed: 10/26/2022]
Abstract
The incorporation and subcellular localization of photosensitizers are critical determinants of their efficiency. Here, we correlate these properties with the interactions of photosensitizers with membrane-models and low density lipoproteins (LDL) in acellular systems. Focus was given on dynamics aspects. Two amphiphilic photosensitizers, deuteroporphyrin (DP) and aluminum phthalocyanine sulfonated on two adjacent isoindole units (AlPcS2a) were selected. The phthalocyanine was bound to LDL with an overall association constant around 5 x 10(7)M(-1). Biphasic association kinetics was indicative of two types of sites. The release of the phthalocyanine into the bulk aqueous medium occurred within less than a second. A similar behavior was found previously for deuteroporphyrin although its affinity was somewhat higher (5.5 x 10(8)M(-1)). Both compounds were previously characterized by high affinity for membrane-models and quick exchange with the bulk solution. However, they strongly differed by their rate of transfer through the lipid bilayer, in the range of seconds for the porphyrin, several hours for the phthalocyanine. In the case of the porphyrin, fluorescence microscopy on human fibroblasts showed diffuse labeling with no significant modification of the distribution upon vectorization by LDL. In contrast, the phthalocyanine was localized in intracellular vesicles. Vectorization by LDL favored lysosomal localization although little effect was found on the overall uptake as shown by extraction experiments. The role of lipoproteins in the cellular localization of photosensitizers is significantly more important for photosensitizers not freely diffusing through bilayers. The dynamics of the interactions of photosensitizers with membranes appears as an important determinant of their subcellular localization.
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Affiliation(s)
- Stéphanie Bonneau
- Laboratoire de Physicochimie Biomoléculaire et Cellulaire, Université Pierre et Marie Curie, CNRS UMR 7033, 75005 Paris, France
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Kessel D, Luguya R, Vicente MGH. Localization and photodynamic efficacy of two cationic porphyrins varying in charge distributions. Photochem Photobiol 2004; 78:431-5. [PMID: 14653572 DOI: 10.1562/0031-8655(2003)078<0431:lapeot>2.0.co;2] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Two meso-tetraphenylporphyrin derivatives bearing adjacent: 5,10-di[4-(N-trimethylaminophenyl)-15,20-diphenylporphyrin (DADP-a) or opposite: 5,15-di[4-(N-trimethylaminophenyl)-10,20-diphenylporphyrin (DADP-o) cationic-N-(CH3)3+ groups on two of the para-phenyl positions were examined with regard to photodynamic properties as a function of charge distribution. The two adjacent positive charges in the DADP-a structure result in a molecular distortion (asymmetry), likely from electrostatic repulsion. This could be responsible for the unusual interaction of this compound with some solvents and detergent micelles. In contrast, DADP-o is a much more symmetric molecule. In a cellular environment, fluorescence spectra of the two agents were essentially identical. Subcellular localization played a major role in photodynamic efficacy. DADP-a localized in mitochondria, and irradiation of photosensitized cells (640-650 nm) resulted in a rapid loss of the mitochondrial membrane potential (delta(psi)m), usually a prelude to apoptotic cell death. In contrast, DADP-o localized in lysosomes, and extensive lysosomal photodamage was observed after irradiation. Both steady-state accumulation levels and absorbance spectra favored DADP-o, but the light dose required for a 90% cell kill was two-fold greater for DADP-o than for DADP-a, at a constant extracellular sensitizer concentration. These data indicate that, on a photons/cell basis, DADP-a was five-fold more efficacious. Fluorescence emission spectra in different solvents and detergents demonstrated a tendency for DADP-a association. We interpret these results to indicate partition of both drugs to membrane loci, with mitochondriabeing the more lethal site for photodamage.
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Affiliation(s)
- David Kessel
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA.
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19
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Kessel D, Luguya R, Vicente MGH. Localization and photodynamic efficacy of two cationic porphyrins varying in charge distributions. Photochem Photobiol 2004. [PMID: 14653572 DOI: 10.1562/0031-8655(2003)078%3c0431:lapeot%3e2.0.co;2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Two meso-tetraphenylporphyrin derivatives bearing adjacent: 5,10-di[4-(N-trimethylaminophenyl)-15,20-diphenylporphyrin (DADP-a) or opposite: 5,15-di[4-(N-trimethylaminophenyl)-10,20-diphenylporphyrin (DADP-o) cationic-N-(CH3)3+ groups on two of the para-phenyl positions were examined with regard to photodynamic properties as a function of charge distribution. The two adjacent positive charges in the DADP-a structure result in a molecular distortion (asymmetry), likely from electrostatic repulsion. This could be responsible for the unusual interaction of this compound with some solvents and detergent micelles. In contrast, DADP-o is a much more symmetric molecule. In a cellular environment, fluorescence spectra of the two agents were essentially identical. Subcellular localization played a major role in photodynamic efficacy. DADP-a localized in mitochondria, and irradiation of photosensitized cells (640-650 nm) resulted in a rapid loss of the mitochondrial membrane potential (delta(psi)m), usually a prelude to apoptotic cell death. In contrast, DADP-o localized in lysosomes, and extensive lysosomal photodamage was observed after irradiation. Both steady-state accumulation levels and absorbance spectra favored DADP-o, but the light dose required for a 90% cell kill was two-fold greater for DADP-o than for DADP-a, at a constant extracellular sensitizer concentration. These data indicate that, on a photons/cell basis, DADP-a was five-fold more efficacious. Fluorescence emission spectra in different solvents and detergents demonstrated a tendency for DADP-a association. We interpret these results to indicate partition of both drugs to membrane loci, with mitochondriabeing the more lethal site for photodamage.
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Affiliation(s)
- David Kessel
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA.
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Janczak J, Kubiak R. Stereochemistry and properties of the M(II)N(py) coordination bond in the low-spin dipyridinated iron(II) and cobalt(II) phthalocyanines. Inorganica Chim Acta 2003. [DOI: 10.1016/s0020-1693(02)01060-5] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Gomes ER, Almeida RD, Carvalho AP, Duarte CB. Nitric oxide modulates tumor cell death induced by photodynamic therapy through a cGMP-dependent mechanism. Photochem Photobiol 2002; 76:423-30. [PMID: 12405151 DOI: 10.1562/0031-8655(2002)076<0423:nomtcd>2.0.co;2] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Photodynamic therapy (PDT) of cancer is a very promising technique based on the formation of singlet oxygen induced by a sensitizer after irradiation with visible light. The stimulation of tumor growth by nitric oxide (NO) was reported recently, and NO was shown to have a protective effect against PDT-induced tumor death. We investigated a putative direct effect of NO on tumor cell death induced by PDT, using the human lymphoblastoid CCRF-CEM cells and bisulfonated aluminum phthalocyanine (AlPcS2) as a sensitizer. Cells were incubated with AlPcS2 in the presence or absence of NO donors ((Z)-1-[(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate, hydroxylamine and S-nitroso-N-acetylpenicillamine) or L-arginine. Under these conditions, in the absence of NO donors or L-arginine the cells died rapidly by apoptosis upon photosensitization. In the presence of NO donors or L-arginine, apoptotic cell death after photosensitization was significantly decreased. Modulation of cell death by NO was not due to S-nitrosylation of caspases and occurred at the level or upstream of caspase-9 processing. The protective effect of NO was reversed by incubating the cells with 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, an inhibitor of guanylyl cyclase, or with KT5823, an inhibitor of protein kinase G (PKG). Incubation with 8-bromo-cyclic guanosine monophosphate, a membrane permeable cyclic guanosine monophosphate analog, also decreased cell death induced by PDT. Although the protective effect of NO against apoptotic cell death in several models has been attributed to an increase in the expression of heme oxygenase-1, heat shock protein 70 or Bcl-2, this was not the case under our experimental conditions. These results show that NO decreases the extent of apoptotic cell death after PDT treatment through a PKG-dependent mechanism, upstream or at the level of caspase activation.
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Affiliation(s)
- Edgar R Gomes
- Center for Neuroscience of Coimbra, Department of Zoology, University of Coimbra, Portugal
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22
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Janczak J, Kubiak R. Synthesis and characterisation of dipyridinated magnesium phthalocyaninato(2-) complex. Polyhedron 2002. [DOI: 10.1016/s0277-5387(01)00988-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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23
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Janczak J, Kubiak R. X-ray single crystal investigations of magnesium phthalocyanine. The 4+1 coordination of the Mg ion and its consequence. Polyhedron 2001. [DOI: 10.1016/s0277-5387(01)00829-4] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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24
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Lee CC, Pouge BW, Strawbridge RR, Moodie KL, Bartholomew LR, Burke GC, Hoopes PJ. Comparison of photosensitizer (AIPcS2) quantification techniques: in situ fluorescence microsampling versus tissue chemical extraction. Photochem Photobiol 2001; 74:453-60. [PMID: 11594060 DOI: 10.1562/0031-8655(2001)074<0453:copaqt>2.0.co;2] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A noninvasive in situ fluorescence-based method for the quantification of the photosensitizer chloroaluminum disulfonated phthalocyanine was compared to the highly accurate but nonreal time ex vivo spectrofluorometry method. Our in vivo fluorescence technique is designed to allow real-time assessment of photosensitizer in tumor and normal tissues and therefore temporally optimal light delivery. Laser-induced fluorescence was used to measure photosensitizer concentration from multiple microscopic regions of tissue. Ex vivo chemical extraction was used to quantify photosensitizer concentration in the same volume of tissue. The amount of photosensitizer in the vascular and/or parenchymal compartments of skeletal muscle and liver was determined by quantifying fluorescent signal in vivo, ex vivo and after blood removal. Confocal microscopy was used to spatially document photosensitizer localization 30 min and 24 h after delivery. While a linear correlation can exist between the fluorescence intensity measured by our fiber-optic bundle system and actual tissue concentration, temporal changes to this calibration line exist as the photosensitizer changes its partitioning fraction between the blood (vasculature) and the tissue parenchyma. In situ photosensitizer fluorescence microsampling (dosimetry) systems can be performed in real time and linearly correlated to actual tissue concentration with minimal intertissue variance. Tissue-specific differences may require temporal alterations in the calibration.
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Affiliation(s)
- C C Lee
- Department of Surgery, Dartmouth-Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH 03756, USA
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Lilge L, Portnoy M, Wilson BC. Apoptosis induced in vivo by photodynamic therapy in normal brain and intracranial tumour tissue. Br J Cancer 2000; 83:1110-7. [PMID: 10993661 PMCID: PMC2363569 DOI: 10.1054/bjoc.2000.1426] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The apoptotic response of normal brain and intracranial VX2 tumour following photodynamic therapy (PDT) mediated by 5 different photosensitizers (Photofrin, 5-aminolaevulinic acid (ALA)-induced protoporphyrin IX (PpIX), chloroaluminium phthalocyanine (AlCIPc), Tin Ethyl Etiopurpurin (SnET(2)), and meta -tetra(hydroxyphenyl)chlorin (m THPC)) was evaluated following a previous analysis which investigated the necrotic tissue response to PDT at 24 h post treatment. Free DNA ends, produced by internucleosomal DNA cleavage in apoptotic cells, were stained using a TUNEL (terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labelling) assay. Confocal laser scanning microscopy (CLSM) was used to quantify the local incidence of apoptosis and determine its spatial distribution throughout the brain. The incidence of apoptosis was confirmed by histopathology, which demonstrated cell shrinkage, pyknosis and karyorrhexis. At 24 h post PDT, AlClPc did not cause any detectable apoptosis, while the other photosensitizers produced varying numbers of apoptotic cells near the region of coagulative necrosis. The apoptotic response did not appear to be related to photosensitizer dose. These results suggest that at this time point, a minimal and fairly localized apoptotic effect is produced in brain tissues, the extent of which depends largely on the particular photosensitizer.
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Affiliation(s)
- L Lilge
- Photonics Research Ontario, Department of Medical Biophysics and, Ontario Cancer Institute, University of Toronto, 610 University Avenue, Toronto, Ontario, M5G 2M9
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26
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Janczak J, Kubiak R. Crystal and molecular structure of 2,3-dicyanonaphthalene: a naphthalocyanine precursor. J Mol Struct 2000. [DOI: 10.1016/s0022-2860(99)00143-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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27
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Affiliation(s)
- H Ali
- MRC Group in the Radiation Sciences, Department of Nuclear Medicine and Radiobiology, Faculty of Medicine, Université de Sherbrooke, Sherbrooke, Québec, Canada J1H 5N4
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28
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Janczak J, Kubiak R. Indate(III) phthalocyanines: synthesis, spectroscopy and crystal structure of iodophthalocyaninato(2-) indate(III). Inorganica Chim Acta 1999. [DOI: 10.1016/s0020-1693(99)00082-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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29
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Aoudia M, Cheng G, Kennedy VO, Kenney ME, Rodgers MAJ. Synthesis of a Series of Octabutoxy- and Octabutoxybenzophthalocyanines and Photophysical Properties of Two Members of the Series. J Am Chem Soc 1997. [DOI: 10.1021/ja963702q] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mohamed Aoudia
- Contribution from the Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, and Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106
| | - Gongzhen Cheng
- Contribution from the Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, and Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106
| | - Vance O. Kennedy
- Contribution from the Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, and Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106
| | - Malcolm E. Kenney
- Contribution from the Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, and Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106
| | - Michael A. J. Rodgers
- Contribution from the Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, and Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106
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Abstract
Photodynamic therapy (PDT) has, during the last quarter century, developed into a fully fledged biomedical field with its own association, the International Photodynamic Association (IPA) and regular conferences devoted solely to this topic. Recent approval of the first PDT sensitizer, Photofrin (porfimer sodium), by health boards in Canada, Japan, the Netherlands and United States for use against certain types of solid tumors represents, perhaps, the single most significant-indicator of the progress of PDT from a laboratory research concept to clinical reality. The approval of Photofrin will undoubtedly encourage the accelerated development of second-generation photosensitizers, which have recently been the subject of intense study. Many of these second-generation drugs show significant differences, when compared to Photofrin, in terms of treatment times postinjection, light doses and drug doses required for optimal results. These differences can ultimately be attributed to variations in either the quantum efficiency of the photosensitizer in situ, which is in turn affected by aggregation state, localized concentration of endogenous quenchers and primary photophysics of the dye, or the intratumoral and intracellular localization of the photosensitizer at the time of activation with light. The purpose of this review is to bring together data relating to the biodistribution and pharmacokinetics of second-generation sensitizers and attempt to correlate this with structural and electronic features of these molecules. As this requires a clear knowledge of photosensitizer structure, only chemically well-characterized compounds are included, e.g. Photofrin and crude sulfonated phthalocyanines have been excluded as they are known to be complex mixtures. Nonporphyrin-based photosensitizers, e.g. rose bengal and the hypericins, have also been omitted to allow meaningful comparisons to be made between different compounds. As the intracellular distribution of photosensitizers to organelles and other subcellular structures can have a large effect on PDT efficacy, a section will be devoted to this topic.
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Affiliation(s)
- R W Boyle
- Department of Chemistry, University of British Columbia, Vancouver, Canada
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31
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Peng Q, Moan J, Nesland JM. Correlation of subcellular and intratumoral photosensitizer localization with ultrastructural features after photodynamic therapy. Ultrastruct Pathol 1996; 20:109-129. [PMID: 8882357 DOI: 10.3109/01913129609016306] [Citation(s) in RCA: 128] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Photodynamic therapy (PDT) of cancer typically involves systemic administration of tumor-localizing photosensitizers followed 48-72 h later by exposure to light of appropriate wavelengths. Knowledge about the distribution of photosensitizers in tissues is still fragmentary. In particular, little is known as to the detailed localization patterns of photosensitizers in neoplastic and normal tissues as well as the relationship between such patterns and the actual targets for the photosensitizing effect. This review focuses on ultrastructural features seen in treated cells and tumors. An attempt is made to correlate these findings with the subcellular/intratumoral localization pattern of the photosensitizers in tumor cell lines in vitro and in tumor models in vivo. Several subcellular sites are main targets of PDT with different sulfonated aluminum phthalocyanines (AIPcSn) in the human tumor cell line LOX. Nuclei are not among the primary targets. Overall, the ultrastructural changes correlate well with the data about the subcellular localization patterns for each analogue of AIPcSn in the same cell line. Similar findings are also obtained for the family of sulfonated mesotetraphenylporphines (TPPSn) in the NHIK 3025 cell line. The mechanisms involved in the killing of tumors by PDT seem to be a complex interplay between direct and indirect (via vascular damage) effects on neoplastic cells according to the intratumoral localization pattern of the applied dye. Several factors can affect the localization pattern of a drug, such as its chemical character, the mode of drug delivery, the time interval between drug administration and light exposure, and tumor type. Furthermore, whether local immune reactions (such as macrophages) and apoptosis (programmed cell death) are involved in the destruction of neoplastic cells by PDT in vivo is still an enigma. A general model for PDT-induced tumor destruction is suggested.
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Affiliation(s)
- Q Peng
- Department of Pathology and Biophysics, Norwegian Radium Hospital, Oslo, Norway
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32
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Peng Q, Moan J. Correlation of distribution of sulphonated aluminium phthalocyanines with their photodynamic effect in tumour and skin of mice bearing CaD2 mammary carcinoma. Br J Cancer 1995; 72:565-74. [PMID: 7669563 PMCID: PMC2033870 DOI: 10.1038/bjc.1995.375] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
A chemical extraction assay and fluorescence microscopy incorporating a light-sensitive thermoelectrically cooled charge-coupled device (CCD) camera was used to study the kinetics of uptake, retention and localisation of disulphonated aluminium phthalocyanine (A1PcS2) and tetrasulphonated aluminium phthalocyanine (A1PcS4) at different time intervals after an i.p. injection at a dose of 10 mg kg-1 body weight (b.w.) in tumour and surrounding normal skin and muscle of female C3D2/F1 mice bearing CaD2 mammary carcinoma. Moreover, the photodynamic effect on the tumour and normal skin using sulphonated aluminium phthalocyanines (A1PcS1, A1PcS2, A1pcS4) and Photofrin was compared with respect to dye, dye dose and time interval between dye administration and light exposure. The maximal concentrations of A1PcS2 in the tumour tissue were reached 2-24 h after injection of the dye, while the amounts of A1PcS4 peaked 1-2 h after the dye administration. A1PcS2 was simultaneously localised in the interstitium and in the neoplastic cells of the tumour, whereas A1PcS4 appeared to localise only in the stroma of the tumour. The photodynamic efficiency (light was applied 24 h after dye injection at a dose of 10 mg kg-1 b.w.) of the tumours was found to decrease in the following order: A1PcS2 > A1PcS4 > Photofrin > A1PcS1. Furthermore, photodynamic efficacy was strongly dependent upon dye doses and time intervals between dye administration and light exposure: the higher the dose, the higher the photodynamic efficiency. The most efficient photodynamic therapy (PDT) of the tumour was reached (day 20 tumour-free) when light exposure took place 2 h after injection of A1PcS2 (10 mg kg-1). A dual intratumoral localisation pattern of the dye, as found for A1PcS2, seems desirable to obtain a high photodynamic efficiency. The kinetic patterns of uptake, retention and localisation of A1PcS2 and A1PcS4 are roughly correlated with their photodynamic effect on the tumour and normal skin.
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Affiliation(s)
- Q Peng
- Department of Pathology, Norwegian Radium Hospital, Montebello, Oslo
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33
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Peavy GM, Krasieva TB, Tromberg BJ, Eusantos ED, Berns MW. Variation in the distribution of a phthalocyanine photosensitizer in naturally occurring tumors of animals. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 1995; 27:271-5. [PMID: 7769537 DOI: 10.1016/1011-1344(94)07075-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- G M Peavy
- Beckman Laser Institute and Medical Clinic, College of Medicine, University of California, Irvine 92715, USA
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Ikeda I, Yamashita Y, Ono T, Ogawa H. Selective phototoxic destruction of rat Merkel cells abolishes responses of slowly adapting type I mechanoreceptor units. J Physiol 1994; 479 ( Pt 2):247-56. [PMID: 7799224 PMCID: PMC1155743 DOI: 10.1113/jphysiol.1994.sp020292] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
1. The fluorescent dye quinacrine which accumulates in Merkel cells in touch domes was administered to rats and the effects of excitation light irradiation on the mechanical responses of slowly adapting (SA) type I units innervating the touch domes were investigated. 2. Histological examination showed that after 10 min of irradiation degeneration was specifically localized to Merkel cells loaded with quinacrine. Nerve terminals associated with Merkel cells remained intact, even after treatment. 3. In SA type I units, responses to standard stimulation (a 100 ms ramp followed by a 2.9 s plateau of 400 microns constant displacement) decreased significantly after irradiation of the domes with quinacrine-excitation light through a 'B' filter ('B' light). With 5 min irradiation, the response decreased to 52 +/- 7% (n = 10, mean +/- S.E.M.) of the pretreated value, to 17 +/- 4% with a 10 min treatment and practically disappeared within 20 min. 4. In SA type I units with non-loaded Merkel cells, the response increased to 119 +/- 8% (n = 13) with 5 min irradiation and was 99 +/- 9% with the 10 min treatment. At around 15 min after the onset of irradiation there was a gradual decrease and within 60 min the response disappeared. 5. When responses were divided into phasic (0-120 ms after the onset of stimulation) and tonic (120-3000 ms) components, 'tonic' responses were more affected than 'phasic' ones in quinacrine-loaded SA type I units. 6. Stimulus-response curves shifted to the right and downwards in SA type I units with quinacrine-loaded Merkel cells after irradiation, but no significant change was seen in SA type I units without quinacrine. 7. Our observations are consistent with the hypothesis that Merkel cells are responsible for mechanoelectric transduction in SA type I units.
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Affiliation(s)
- I Ikeda
- Department of Physiology, Kumamoto University School of Medicine, Japan
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35
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Mank A, Gooijer C, Lingeman H, Velthorst N, Brinkman U. Selective and sensitive in vitro detection method for aluminum phthalocyanine photosensitizers, using liquid chromatography and diode-laser induced fluorescence. Anal Chim Acta 1994. [DOI: 10.1016/0003-2670(94)80045-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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36
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van Leengoed HL, van der Veen N, Versteeg AA, Ouellet R, van Lier JE, Star WM. In vivo photodynamic effects of phthalocyanines in a skin-fold observation chamber model: role of central metal ion and degree of sulfonation. Photochem Photobiol 1993; 58:575-80. [PMID: 8248334 DOI: 10.1111/j.1751-1097.1993.tb04935.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Six sulfonated metallophthalocyanines, chelated with either aluminum or zinc and sulfonated to different degrees, were studied in vivo for their photodynamic activity in a rat skin-fold chamber model. The chamber, located on the back of female WAG/Rij rats, contained a syngeneic mammary carcinoma implanted into a layer of subcutaneous tissue. Twenty-four hours after intravenous administration of 2.5 mumol/kg of one of the dyes, the chambers received a treatment light dose of 600 J/cm2 with monochromatic light of 675 nm at a power density of 100 mW/cm2. During light delivery and up to a period of 7 days after treatment, vascular effects of tumor and normal tissue were scored. Tumor cell viability was determined by histology and by reimplantation of the chamber contents into the skin of the same animal, either 2 h after treatment or after the 7 day observation period. Vascular effects of both tumor and subcutaneous tissue were strongest with dyes with the lowest degree of sulfonation and decreased with increasing degree of sulfonation. Tumor regrowth did not occur with aluminum phthalocyanine mono- and disulfonate and with zinc phthalocyanine monosulfonate. With the protocol that was used, complete necrosis without recovery was only observed when reimplantation took place at the end of the 7 day follow-up period. Reimplantation 2 h after treatment always resulted in tumor regrowth. At this interval, the presence of viable tumor cells was confirmed histologically. In general tumor tissue vasculature was more susceptible to photodynamic damage than vasculature of the normal tissue. The effect on the circulation of both tumor and normal tissue increased with decreasing degree of sulfonation.(ABSTRACT TRUNCATED AT 250 WORDS)
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Jori G, Reddi E. The role of lipoproteins in the delivery of tumour-targeting photosensitizers. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1993; 25:1369-75. [PMID: 8224351 DOI: 10.1016/0020-711x(93)90684-7] [Citation(s) in RCA: 130] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
1. Serum lipoproteins play an important role in the in vivo transport of several porphyrinoid derivatives having a moderate or high degree of hydrophobicity. 2. There appears to exist a correlation between the extent of photosensitizer association with low-density lipoproteins (LDL) and the efficiency of tumour targeting by some classes of photosensitizers, such as differently sulphonated porphyrins and phthalocyanines, haematoporphyrin dialkylethers and unsubstituted phthalocyanines and naphthalocyanines. 3. In all cases, LDL-carried photosensitizers are preferentially released to malignant cells; hence, direct cell damage appears to be the major determinant of tumour damage consequent to photodynamic therapy. 4. Present evidence suggests that the LDL-associated photosensitizer is accumulated by tumour cells largely via a receptor-mediated endocytotic process. 5. Thus, the use of delivery systems for orientating a systemically injected photosensitizer towards lipoproteins has been explored; promising results have been obtained by incorporation of the dye into liposomal vesicles, oil emulsions or inclusion complexes, as well as by precomplexation of the dye with LDL. 6. Moreover, a suitable choice of the chemical constituents of the delivery system and the experimental conditions allows one to modulate the photosensitizer distribution among the different lipoproteins. 7. The occurrence of tumour-targeting strategies other than the LDL pathway is briefly discussed.
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Affiliation(s)
- G Jori
- Department of Biology, University of Padova, Italy
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38
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Korbelik M. Distribution of disulfonated and tetrasulfonated aluminum phthalocyanine between malignant and host cell populations of a murine fibrosarcoma. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 1993; 20:173-81. [PMID: 7505820 DOI: 10.1016/1011-1344(93)80148-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Levels of disulfonated and tetrasulfonated aluminum phthalocyanines (AlPcS2,4) were measured in cells derived from FsaR tumors (murine fibrosarcoma) using a fluorescence-activated cell sorter (FACS). The tumors were excised from animals injected with the sensitizer 24 h earlier and enzymatically dissociated. Before flow cytometry, the cells were stained with fluorescein isothiocyanate-conjugated anti-mouse monoclonal antibodies to specific immune cell membrane markers (Mac1, Fc receptor (FcR) or CD45). Staining to FcR and CD45 was combined with a DNA stain Hoechst 33342. This enabled concomitant discrimination to be made by the FACS between different populations of tumor-infiltrating host cells and malignant cells. The results showed on average 1.49 times higher AlPcS2 levels and 1.16 times higher AlPcS4 levels in Mac1-positive (Mac1+) compared with Mac1-negative (Mac1-) tumor cell populations. The same type of experiments performed with SCCVII tumor (squamous cell carcinoma) gave average Mac1+/Mac1- ratios of 1.75 and 1.45 for AlPcS2 and AlPcS4 respectively. The data using other antibodies and DNA staining are consistent with the conclusion that, based on average per cell content, elevated levels of AlPcS2, and to a lesser extent AlPcS4, are retained in tumor-associated macrophages (TAM). The levels of these photosensitizers in other leukocytes and in non-immune host cells were not substantially different from those in malignant tumor cells. It is also shown that elevated levels of AlPcS2 and AlPcS4 are not localized in all TAM, but rather in a fraction of this cell population characterized by extremely high photosensitizer content.
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Affiliation(s)
- M Korbelik
- B.C. Cancer Research Center, Vancouver, Canada
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39
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Bishop SM, Khoo BJ, MacRobert AJ, Simpson MS, Phillips D, Beeby A. Characterisation of the photochemotherapeutic agent disulphonated aluminium phthalocyanine and its high-performance liquid chromatographic separated components. J Chromatogr A 1993; 646:345-50. [PMID: 8408436 DOI: 10.1016/0021-9673(93)83347-u] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Disulphonated aluminium phthalocyanine (AlPcS2), a potential clinical photosensitiser, has been synthesised in a reproducible form and shown by reversed-phase HPLC to consist of at least eight components which are believed to be individual AlPcS2 regioisomers. These components have been isolated either as single bands or mixtures of two using preparative reversed-phase HPLC methods. The number and position of sulphonate groups per phthalocyanine macromolecule for each component has been determined using a chemical degradation and HPLC assay. Results suggest that the bulk AlPcS2 material consists mostly (> 60%) of an amphiphilic alpha-, alpha-disubstituted regioisomer, with both sulphonate groups substituted to the same side of the molecule (adjacent form). Possible structures for some of the other separated components of AlPcS2 are also presented.
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Affiliation(s)
- S M Bishop
- Department of Chemistry, Imperial College, Kensington, London, UK
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40
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Peng Q, Brown SB, Moan J, Nesland JM, Wainwright M, Griffiths J, Dixon B, Cruse-Sawyer J, Vernon D. Biodistribution of a methylene blue derivative in tumor and normal tissues of rats. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 1993; 20:63-71. [PMID: 8229471 DOI: 10.1016/1011-1344(93)80132-s] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
By using a chemical extraction procedure and confocal laser scanning fluorescence microscopy we have investigated the kinetic patterns of uptake and biolocalization of a methylene blue derivative (MBD) in tumors and various normal tissues of Wistar rats bearing fibrosarcoma (Leeds ovarian tumor) after intravenous injection of MBD (10 mg kg-1 body weight). Similar kinetics of accumulation and elimination of MBD fluorescence were found in tumor tissue and surrounding normal skin and muscle tissues. However, the tumor:skin and tumor:muscle ratios of the MBD fluorescence intensity were found to be 9 and 4, respectively, 4 h after intravenous injection, indicating selective uptake of MBD by the tumor tissue. MBD was localized on the walls of all the vessels and extensively in the area of neoplastic cellular and tumorigenic fibrous components in the tumor tissue. Interestingly, no MBD fluorescence could be detected in the metastatic neoplastic cells in the remote lymph nodes. In the skin, MBD was mainly distributed in the keratinized epithelium of the epidermis, hair follicles and their accessories, while little was found both in the epidermis and dermis. In most other tissues, the maximal fluorescence intensity of MBD was found 1-4 h after injection, after which it decreased dramatically to almost undetectable levels 120 h postinjection. Strong fluorescence of MBD was seen in the tracheal mucosal epithelium, while little fluorescence was noted in the transitional epithelium of bladder. The kinetics of biolocalization of MBD in some other tissues (liver, spleen, kidney, brain, muscle, lung, heart) were also studied.
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Affiliation(s)
- Q Peng
- Department of Biophysics, Norwegian Radium Hospital, Oslo
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Boyle RW, Leznoff CC, van Lier JE. Biological activities of phthalocyanines--XVI. Tetrahydroxy- and tetraalkylhydroxy zinc phthalocyanines. Effect of alkyl chain length on in vitro and in vivo photodynamic activities. Br J Cancer 1993; 67:1177-81. [PMID: 8512803 PMCID: PMC1968488 DOI: 10.1038/bjc.1993.222] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Zinc phthalocyanine substituted with four hydroxyl groups attached to the macrocycle, either directly or via spacer chains of three or six carbon atoms, were tested for their photodynamic ability to inactivate Chinese hamster lung fibroblasts (line V-79) in vitro, and to induce regression of EMT-6 tumours grown subcutaneously in Balb/c mice. Their potential to inflict direct cell killing during photodynamic therapy was investigated by examining vascular stasis immediately following photoirradiation using fluorescein as a marker, and also by an in vivo/in vitro EMT-6 cell survival assay. Both of the tetraalkylhydroxy substituted zinc phthalocyanines are effective photodynamic sensitisers in vivo with the tetrapropylhydroxy compound exhibiting about twice the activity of the tetrahexylhydroxy analogue. The differences in activities were accentuated in vitro, the tetrapropylhydroxy compound was two orders of magnitude more potent than the tetrahexylhydroxy analogue in photoinactivating V-79 cells. The tetrahydroxy compound lacking spacer chains failed to exhibit photodynamic activity in either system. Tumour response with the active compounds was preceded by vascular stasis immediate following irradiation which suggests, together with the absence of activity in the in vivo/in vitro assay, that tumour regression involves an indirect response to the photodynamic action rather than direct cell killing. These data demonstrate the importance of the spatial orientation of functional groups around the macrocycle of photosensitisers for their efficacy in the photodynamic therapy of cancer.
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Affiliation(s)
- R W Boyle
- MRC Group in the Radiation Sciences, Faculty of Medicine, University of Sherbrooke, Quebec, Canada
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Winkelman JW, Arad D, Kimel S. Stereochemical factors in the transport and binding of photosensitizers in biological systems and in photodynamic therapy. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 1993; 18:181-9. [PMID: 8350185 DOI: 10.1016/1011-1344(93)80061-d] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The uptake and biological activity of porphyrins and phthalocyanines in tumours were correlated with the geometrical features of the photosensitizer molecules. The data suggest that a critical distance of approximately 1.2 nm between oxygen atoms (originating in SO3-, COO- or OH substituents) characterizes a biologically active photosensitizer for photodynamic therapy. We propose that tubulin, which is available in large amounts during mitosis, is the main receptor molecule which binds these photosensitizers. Basic amino acid residues or tightly bound cations in tubulin or homologous proteins may act as binding sites on the receptor molecule.
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Affiliation(s)
- J W Winkelman
- Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115
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43
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Chen JY, Chen W, Cai HX, Dong RC. Studies on pharmacokinetics of sulfonated aluminum phthalocyanine in a transplantable mouse tumor by in vivo fluorescence. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 1993; 18:233-7. [PMID: 8350189 DOI: 10.1016/1011-1344(93)80069-l] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The pharmacokinetic properties of sulfonated aluminum phthalocyanine (A1PCS) in mouse bearing transplantable S180 tumors were determined by an in vivo method. In vivo fluorescence measurements were made on the hind legs of mice, one leg bearing a tumor and the other, without a tumor, being used as a control. These in vivo data were compared with the results obtained from in vitro extraction fluorescence experiments. The results obtained by the two methods showed remarkable agreement, both procedures demonstrating that the concentration of A1PCS in the tumor was substantially higher than that in muscle. In both cases, the maximum tumor to muscle A1PCS concentration ratio occurred at 24-36 h after drug administration. The agreement between the in vivo and in vitro measurements shows that the in vivo fluorescence technique can be used successfully in pharmacokinetic studies of metallo-phthalocyanines in a superficial tumor model. The in vivo technique has the advantages of being rapid and convenient.
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Affiliation(s)
- J Y Chen
- Physics Department, Fudan University, Shanghai, China
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Peng Q, Moan J, Warloe T, Nesland JM, Rimington C. Distribution and photosensitizing efficiency of porphyrins induced by application of exogenous 5-aminolevulinic acid in mice bearing mammary carcinoma. Int J Cancer 1992; 52:433-43. [PMID: 1399120 DOI: 10.1002/ijc.2910520318] [Citation(s) in RCA: 116] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
By means of a chemical extraction procedure and confocal laser scanning microscopy, we investigated the kinetic patterns of uptake and biolocalization of 5-aminolevulinic acid (ALA)-induced porphyrins in s.c. transplanted tumors, adjacent normal skin and muscle, and liver of mice bearing mammary carcinoma, after i.p. injection of 250 mg/kg ALA or topical application of ALA (20% in an oil-in-water emulsion). Furthermore, we evaluated the tumor responses after either i.p. injection or topical application of 5-ALA followed by laser irradiation (632 nm, 150 mW/cm2, 25 min) by measuring the treated tumor regression/regrowth time and by light and electron microscopy. Strong fluorescence of ALA-induced porphyrins was detected in the tumor, skin and liver tissues, while little fluorescence was seen in the adjacent muscle tissue. Moreover, the highest amounts of ALA-induced porphyrins in the tumor and skin tissues were found 1 hr after i.p. injection, whereas the amounts of the porphyrins in both tissues increased with increasing time after topical application of ALA. The fluorescence of the porphyrins was localized in several components of the skin tissue (epidermis, hair follicles and their associated sebaceous glands). Furthermore, the fluorescence was diffusely distributed in the s.c. transplanted tumor tissue. Little could be observed under a confocal laser scan microscope (CLSM) in the muscle tissue. The uptake and biolocalization data correlate well with the results of PCT efficiency of the same tumor model with ALA-induced porphyrins. Light and electron microscopy showed that the mitochondria of the tumor cells and of the endothelial cells and the basal lamina of vascular walls beneath the endothelium in the tumor tissue were initially extensively destroyed after PCT with ALA-induced porphyrins. Thereafter, diffuse degeneration followed by local and/or diffuse severe necrosis of the tumor cells was found. This may be due mainly to the initial damage to mitochondria in the cancerous and endothelial cells and also to the destruction of the vascular wall in the tumor tissue.
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Affiliation(s)
- Q Peng
- Department of Biophysics, Institute for Cancer Research, Oslo, Norway
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Kongshaug M. Distribution of tetrapyrrole photosensitizers among human plasma proteins. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1992; 24:1239-65. [PMID: 1644211 DOI: 10.1016/0020-711x(92)90200-k] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- M Kongshaug
- Department of Biophysics, Norwegian Radium Hospital, Montebello, Oslo
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46
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Boyle RW, Paquette B, van Lier JE. Biological activities of phthalocyanines. XIV. Effect of hydrophobic phthalimidomethyl groups on the in vivo phototoxicity and mechanism of photodynamic action of sulphonated aluminium phthalocyanines. Br J Cancer 1992; 65:813-7. [PMID: 1616852 PMCID: PMC1977750 DOI: 10.1038/bjc.1992.174] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Aluminium phthalocyanines substituted to different degrees with hydrophilic sulphonic acid and hydrophobic phthalimidomethyl groups were investigated in vivo as new agents for the photodynamic therapy of malignant tumours. Parameters studied included the photodynamic action on EMT-6 mammary tumours in BALB/c mice, the therapeutic window and the potential for direct cell killing, assayed via an in vivo/in vitro test. Although the efficiency of photoinactivation of the EMT-6 tumour increases by a factor of ten with reduction of the number of sulphonic acid groups from four to two, no further effect was seen with the addition of the hydrophobic phthalimidomethyl groups. Addition of the latter groups however increased the potential for direct cell killing by a factor of two and expanded the therapeutic window by a factor of four, thus improving the usefulness of the dye as a photosensitiser for the photodynamic therapy of cancer.
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Affiliation(s)
- R W Boyle
- MRC Group in the Radiation Sciences, Faculty of Medicine, University of Sherbrooke, Québec, Canada
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Chan WS, West CM, Moore JV, Hart IR. Photocytotoxic efficacy of sulphonated species of aluminium phthalocyanine against cell monolayers, multicellular spheroids and in vivo tumours. Br J Cancer 1991; 64:827-32. [PMID: 1931602 PMCID: PMC1977473 DOI: 10.1038/bjc.1991.408] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The problem of relying solely on in vitro data to predict photosensitiser efficacy was demonstrated by examining the uptake and the ability to mediate photocytotoxicity of mono-, di-, tri- and tetra-sulphonated species of chloroaluminium phthalocyanine (AlS1-4Pc) in monolayer cultures of murine Colo 26 cells and in both monolayer and spheroid cultures of human WiDr cells. Cells treated in vitro, whether in monolayer or as spheroids, with the less sulphonated derivatives, AlS1Pc and AlS2Pc, were more susceptible to photocytotoxicity than those treated with AlS3Pc, cells treated with AlS4Pc were even less susceptibile to the cytotoxic effects of light irradiation. Generally these results mirrored the cellular uptake in vitro. When WiDr spheroids were increased in size from 250 microns to 500 microns there was a reduction in uptake of AlS1Pc and AlS2Pc which was reflected by the decreased sensitivity of the larger spheroids to the effects of light irradiation. AlS1Pc had no effect against Colo 26 cells growing as s.c. tumours in syngeneic BALB/c mice; whereas AlS3Pc, AlS2Pc and AlS4Pc produced significant reductions in tumour weights 5 days post laser light irradiation. Of these, AlS2Pc had the most dramatic effect on the colony forming efficiency of tumour cells recovered 24 h after PDT. While, despite their effects on tumour size, AlS3Pc and AlS4Pc scarcely affected the subsequent viability of cells from dissociated tumours. Thus the in vitro efficacy of the sulphonated species of phthalocyanines is not necessarily predictive of their in vivo effectiveness.
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Affiliation(s)
- W S Chan
- Biology of Metastasis Laboratory, Imperial Cancer Research Fund, London, UK
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