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Olek M, Machorowska-Pieniążek A, Olek K, Cieślar G, Kawczyk-Krupka A. Photodynamic therapy in the treatment of oral squamous cell carcinoma - The state of the art in preclinical research on the animal model. Photodiagnosis Photodyn Ther 2021; 34:102236. [PMID: 33639322 DOI: 10.1016/j.pdpdt.2021.102236] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 02/21/2021] [Accepted: 02/22/2021] [Indexed: 12/13/2022]
Abstract
BACKGROUND Oral cavity squamous cell carcinoma is a common cancer of the head and neck region. Due to the frequency of diagnoses, high rate of mortality, mutilating nature of classic therapy and numerous complications, new methods of treatment are being sought. One promising solution for treatment that is utilized in many fields of oncology is photodynamic therapy. The purpose of this article is to present a general overview of the use of photodynamic therapy in preclinical in vivo studies on the animal model. MATERIAL AND METHODS A literature search for articles corresponding to the topic of this review was performed using the PubMed and MEDLINE databases using the following keywords: 'oral cavity squamous cell carcinoma,' 'photodynamic therapy,' 'photosensitizer(s),' 'in vivo', and 'animal model'. RESULTS Based on the literature review, the two most used animal models can be distinguished in research on the use of photodynamic therapy for oral squamous cell carcinoma. Studies mainly focus on the evaluation of tumor growth inhibition after using therapies with various photosensitizers on the murine or hamster cheek pouch models. CONCLUDING REMARKS The animal model is a part of preclinical research. Unfortunately, each of the models has its limitations, so it is difficult to extrapolate the results to clinical trials.
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Affiliation(s)
- Marcin Olek
- Department of Orthodontics, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, Katowice, Poland
| | | | - Katarzyna Olek
- Department of Dental Propedeutics, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, Katowice, Poland
| | - Grzegorz Cieślar
- Department of Internal Medicine, Angiology and Physical Medicine, Center for Laser Diagnostics and Therapy, Faculty of Medical Sciences in Zabrze, Medical University of Silesia in Katowice, Poland
| | - Aleksandra Kawczyk-Krupka
- Department of Internal Medicine, Angiology and Physical Medicine, Center for Laser Diagnostics and Therapy, Faculty of Medical Sciences in Zabrze, Medical University of Silesia in Katowice, Poland.
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Mesquita MQ, Dias CJ, Gamelas S, Fardilha M, Neves MGPMS, Faustino MAF. An insight on the role of photosensitizer nanocarriers for Photodynamic Therapy. AN ACAD BRAS CIENC 2018; 90:1101-1130. [PMID: 29873674 DOI: 10.1590/0001-3765201720170800] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 11/19/2017] [Indexed: 12/21/2022] Open
Abstract
Photodynamic therapy (PDT) is a modality of cancer treatment in which tumor cells are destroyed by reactive oxygen species (ROS) produced by photosensitizers following its activation with visible or near infrared light. The PDT success is dependent on different factors namely on the efficiency of the photosensitizer deliver and targeting ability. In this review a special attention will be given to the role of some drug delivery systems to improve the efficiency of tetrapyrrolic photosensitizers to this type of treatment.
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Affiliation(s)
- Mariana Q Mesquita
- Department of Chemistry and QOPNA, University of Aveiro, Aveiro, Portugal
| | - Cristina J Dias
- Department of Chemistry and QOPNA, University of Aveiro, Aveiro, Portugal
| | - Sara Gamelas
- Department of Chemistry and QOPNA, University of Aveiro, Aveiro, Portugal
| | - Margarida Fardilha
- Department of Biomedical Sciences, University of Aveiro, Aveiro, Portugal
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3
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Obata M, Tanaka S, Mizukoshi H, Ishihara E, Takahashi M, Hirohara S. RAFT synthesis of an amphiphilic block copolymer bearing chlorin rings in the hydrophobic segment and its application in photodynamic therapy. ACTA ACUST UNITED AC 2017. [DOI: 10.1002/pola.28716] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Makoto Obata
- Interdisciplinary Graduate School of Medicine and Engineering; University of Yamanashi; 4-4-37 Takeda Kofu 400-8510 Japan
| | - Shuto Tanaka
- Interdisciplinary Graduate School of Medicine and Engineering; University of Yamanashi; 4-4-37 Takeda Kofu 400-8510 Japan
| | - Hiroshi Mizukoshi
- Interdisciplinary Graduate School of Medicine and Engineering; University of Yamanashi; 4-4-37 Takeda Kofu 400-8510 Japan
| | - Eika Ishihara
- Interdisciplinary Graduate School of Medicine and Engineering; University of Yamanashi; 4-4-37 Takeda Kofu 400-8510 Japan
| | - Masaki Takahashi
- Interdisciplinary Graduate School of Medicine and Engineering; University of Yamanashi; 4-4-37 Takeda Kofu 400-8510 Japan
| | - Shiho Hirohara
- Department of Chemical and Biological Engineering; National Institute of Technology, Ube College; 2-14-1 Tokiwadai Ube 755-8555 Japan
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Obata M, Hirohara S. Syntheses, photophysical properties, and photocytotoxicities of tetrakis(fluorophenyl)porphyrin derivatives bearing 2-hydroxyethylthio groups. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2016; 162:324-331. [PMID: 27419616 DOI: 10.1016/j.jphotobiol.2016.07.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 07/07/2016] [Indexed: 11/18/2022]
Abstract
Porphyrin derivatives for photodynamic therapy are frequently modified with hydrophilic groups to improve their water solubility; however, such hydrophilic groups not only improve the solubility but also affect the photodynamic behavior of the compound. The suitable number and pattern of the hydrophilic substituents depend on the nature of the hydrophilic groups. In this article, we explore the optimum architecture for 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin (TFPP) derivatives bearing 2-hydroxyethylthio substituents. All five derivatives, namely mono-, cis-bis-, trans-bis-, tris- and tetrakis-substituted TFPP, were successfully synthesized by the nucleophilic aromatic substitution of TFPP with 2-hydroxyethanethiol, separated, and subsequently identified using ESI-TOF mass spectrometry and (1)H and (19)F NMR spectroscopies. The hydrophilicity of the compounds increased with an increase in the number of 2-hydroxyethylthio groups. The singlet oxygen and hydroxyl radical generation efficiencies were estimated using chemical probes following photoirradiation (λ>500nm). trans-Bissubstituted TFPP exhibited the highest efficiency for both singlet oxygen and hydroxyl radical generation. The photocytotoxicities of the photosensitizers were evaluated in HeLa cells following photoirradiation (λ>500nm, 16Jcm(-2)), and increased with an increase in number of 2-hydroxyethylthio groups. In the case of 2-hydroxyethylthio-substituted TFPPs, the fully substituted TFPP was the most efficient architecture plausibly because of the result of the hydrophilicity of the compound rather than a greater efficiency in the generation of reactive oxygen species.
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Affiliation(s)
- Makoto Obata
- Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 4-4-37 Takeda, Kofu 400-8510, Japan.
| | - Shiho Hirohara
- Department of Chemical and Biological Engineering, National Institute of Technology, Ube College, 2-14-1 Tokiwadai, Ube 755-8555, Japan
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5
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Abstract
Cationic porphyrins (Prs) and phthalocyanines (Pcs) are strong photosensitizers that have drawn much attention for their potential in photodynamic therapy. These compounds have the interesting property of binding to nucleic acids, in particular G-rich quadruplex-forming sequences in DNA and RNA. In this review, we highlight their potential as anticancer drugs.
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6
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Deni E, Zamarrón A, Bonaccorsi P, Carmen Carreño M, Juarranz Á, Puntoriero F, Sciortino MT, Ribagorda M, Barattucci A. Glucose-functionalized amino-OPEs as biocompatible photosensitizers in PDT. Eur J Med Chem 2016; 111:58-71. [PMID: 26854378 DOI: 10.1016/j.ejmech.2016.01.041] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 12/21/2015] [Accepted: 01/21/2016] [Indexed: 12/22/2022]
Abstract
Photodynamic therapy (PDT) is a minimally invasive procedure that can provide a selective eradication of neoplastic diseases by the combined effect of a photosensitizer, light and oxygen. New amino oligo(phenylene-ethynylene)s (OPEs), bearing hydrophilic glucoside terminations, have been prepared, characterized and tested as photosensitizers in PDT. The effectiveness of these compounds in combination with UVA light has been checked on two tumor cell lines (HEp-2 and HeLa cells, derived from a larynx carcinoma and a cervical carcinoma, respectively). The compounds triggered a mitotic blockage that led to the cell death, being the effect active up to 3 μm concentration. The photophysical properties of OPEs, such as high quantum yield, stability, singlet oxygen production, biocompatibility, easy cell-internalization and very good response even at low concentration, make them promising photosensitizers in the application of PDT.
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Affiliation(s)
- Elisa Deni
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali- ChiBioFarAm, Università di Messina, Messina, Italy
| | - Alicia Zamarrón
- Departamento de Biología, Universidad Autónoma de Madrid, Madrid, Spain
| | - Paola Bonaccorsi
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali- ChiBioFarAm, Università di Messina, Messina, Italy
| | - M Carmen Carreño
- Departamento de Química Orgánica, Universidad Autónoma de Madrid, Madrid, Spain
| | - Ángeles Juarranz
- Departamento de Biología, Universidad Autónoma de Madrid, Madrid, Spain
| | - Fausto Puntoriero
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali- ChiBioFarAm, Università di Messina, Messina, Italy
| | - Maria Teresa Sciortino
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali- ChiBioFarAm, Università di Messina, Messina, Italy
| | - María Ribagorda
- Departamento de Química Orgánica, Universidad Autónoma de Madrid, Madrid, Spain.
| | - Anna Barattucci
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali- ChiBioFarAm, Università di Messina, Messina, Italy.
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Jiang J, Yang E, Reddy KR, Niedzwiedzki DM, Kirmaier C, Bocian DF, Holten D, Lindsey JS. Synthetic bacteriochlorins bearing polar motifs (carboxylate, phosphonate, ammonium and a short PEG). Water-solubilization, bioconjugation, and photophysical properties. NEW J CHEM 2015. [DOI: 10.1039/c5nj00759c] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A bacteriochlorin scaffold has been derivatized for life sciences applications.
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Affiliation(s)
- Jianbing Jiang
- Department of Chemistry
- North Carolina State University
- Raleigh
- USA
| | - Eunkyung Yang
- Department of Chemistry
- Washington University
- St. Louis
- USA
| | | | | | | | | | - Dewey Holten
- Department of Chemistry
- Washington University
- St. Louis
- USA
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Jiang J, Vairaprakash P, Reddy KR, Sahin T, Pavan MP, Lubian E, Lindsey JS. Hydrophilic tetracarboxy bacteriochlorins for photonics applications. Org Biomol Chem 2014; 12:86-103. [DOI: 10.1039/c3ob41791c] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Senge MO, Brandt JC. Temoporfin (Foscan®, 5,10,15,20-tetra(m-hydroxyphenyl)chlorin)--a second-generation photosensitizer. Photochem Photobiol 2011; 87:1240-96. [PMID: 21848905 DOI: 10.1111/j.1751-1097.2011.00986.x] [Citation(s) in RCA: 224] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This review traces the development and study of the second-generation photosensitizer 5,10,15,20-tetra(m-hydroxyphenyl)chlorin through to its acceptance and clinical use in modern photodynamic (cancer) therapy. The literature has been covered up to early 2011.
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Affiliation(s)
- Mathias O Senge
- Medicinal Chemistry, Institute of Molecular Medicine, Trinity Centre for Health Sciences, Trinity College Dublin, St. James's Hospital, Dublin 8, Ireland.
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Stamati I, Kuimova MK, Lion M, Yahioglu G, Phillips D, Deonarain MP. Novel photosensitisers derived from pyropheophorbide-a: uptake by cells and photodynamic efficiency in vitro. Photochem Photobiol Sci 2010; 9:1033-41. [PMID: 20532306 DOI: 10.1039/c0pp00038h] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Photodynamic Therapy (PDT) is a minimally invasive procedure used for treating a range of neoplastic diseases, which utilises combined action of light and a PDT drug called a photosensitiser. The efficiency of this treatment depends crucially on the properties of the photosensitiser used, namely on its efficient uptake by cells or by the surrounding vasculature, intracellular localisation, minimal dark toxicity and substantial phototoxicity. In this report we compare the spectroscopic properties, cell uptake and in vitro phototoxicity of two novel hydrophilic photosensitisers derived from pyropheophorbide-a (PPa). Both new photosensitisers have the potential to form bioconjugates with antibody fragments for targeted PDT. We find that the photophysical properties of both new photosensitisers are favourable compared to the parent PPa, including enhanced absorption in the red spectral region and substantial singlet oxygen quantum yields. Both molecules show efficient cellular uptake, but display a different intracellular localisation. Both new photosensitisers exhibit no significant dark-toxicity at concentrations of up to 100 microM. The phototoxicity of the two photosensitisers is strikingly different, with one derivative being 13 times more efficient than the parent PPa and another derivative being 18 times less efficient in SKOV3 ovarian cancer cells. We investigate the reasons behind such drastic differences in phototoxicity using confocal fluorescence microscopy and conclude that intracellular localisation is a crucial factor in the photodynamic efficiency of pheophorbide derivatives. These studies highlight the underlying factors behind creating more potent photosensitisers through synthetic manipulation.
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Affiliation(s)
- Ioanna Stamati
- Division of Cell and Molecular Biology, Faculty of Natural Sciences, Imperial College London, Exhibition Road, SW7 2AZ, UK
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11
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Nawalany K, Rusin A, Kepczyński M, Mikhailov A, Kramer-Marek G, Snietura M, Połtowicz J, Krawczyk Z, Nowakowska M. Comparison of photodynamic efficacy of tetraarylporphyrin pegylated or encapsulated in liposomes: in vitro studies. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2009; 97:8-17. [PMID: 19665390 DOI: 10.1016/j.jphotobiol.2009.07.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2008] [Revised: 04/10/2009] [Accepted: 07/02/2009] [Indexed: 11/24/2022]
Abstract
Two photosensitizing systems: (1) tetrakis(4-hydroxyphenyl)porphyrin (p-THPP) encapsulated in sterically stabilized liposomes (SSL) and (2) p-THPP functionalized by covalent attachment of poly(ethylene glycol) (p-THPP-PEG(2000)) were studied in vitro. The dark and photo cytotoxicity of these systems were evaluated on two cell lines: HCT 116, a human colorectal carcinoma cell line, and DU 145, a prostate cancer cell line and compared with these determined for free p-THPP. It was demonstrated that both encapsulation in liposomes as well as attachment of PEG chain result in pronounced reduction of the dark cytotoxicity of the parent porphyrin. The liposomal formulation showed higher than p-THPP-PEG(2000) photocytotoxicity towards both cell lines used in the studies.
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Affiliation(s)
- Kinga Nawalany
- Faculty of Chemistry, Jagiellonian University, Kraków, Poland
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12
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Abstract
Three free base porphyrins have been prepared that bear a polar and facially encumbering 2,4,6-tris(carboxymethoxy)phenyl motif at one meso (5-) position. The only other substituent (15-position) comprises phenyl, formyl, or p-aminophenyl. The porphyrins exhibit solubility in water (or aqueous buffer solutions) at pH >/=7 and concentrations >1 mM at room temperature. The concise syntheses, water-solubility, and bioconjugatable handle make these porphyrin constructs suitable for biological applications.
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Sibrian-Vazquez M, Jensen TJ, Vicente MGH. Synthesis and cellular studies of PEG-functionalized meso-tetraphenylporphyrins. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2007; 86:9-21. [PMID: 16987669 DOI: 10.1016/j.jphotobiol.2006.08.004] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2006] [Revised: 08/03/2006] [Accepted: 08/07/2006] [Indexed: 11/25/2022]
Abstract
The total syntheses of four PEG-functionalized porphyrins, containing one to four low molecular weight PEG chains linked via amide bonds to the para-phenyl positions of meso-tetraphenylporphyrin, are reported. The hydrophobic character of the PEG-porphyrins decreases with the number of PEG chains linked to the porphyrin ring, while their tendency for aggregation in buffered aqueous solution increases. The porphyrins containing one or two PEG chains accumulated within human HEp2 cells to a much higher extent than those having three or four PEGs at the macrocycle periphery. All PEG-porphyrins were found to be non-toxic in the dark, and only those containing one or two PEG chains were phototoxic (IC(50)=2 microM at 1J/cm(2) light dose). The preferential sites of subcellular localization of the porphyrins containing one or two PEG chains were found to be the mitochondria and endoplasmic reticulum (ER), while those containing three or four PEG chains localize preferentially in the lysosomes.
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Affiliation(s)
- Martha Sibrian-Vazquez
- Department of Chemistry, Louisiana State University, 433 Choppin Hall, Baton Rouge, LA 70803, USA
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Walt H, Nap M, Dorward AM, Leers MP, Tennent BJ, Varga Z, Stallmach T, Björklund V, Beamer WG. Early apoptotic responses in transgenic mouse mammary carcinoma for photodynamic therapy. Photodiagnosis Photodyn Ther 2006; 3:227-33. [DOI: 10.1016/j.pdpdt.2006.07.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2006] [Revised: 07/03/2006] [Accepted: 07/07/2006] [Indexed: 10/24/2022]
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Borbas KE, Mroz P, Hamblin MR, Lindsey JS. Bioconjugatable porphyrins bearing a compact swallowtail motif for water solubility. Bioconjug Chem 2006; 17:638-53. [PMID: 16704201 PMCID: PMC3072562 DOI: 10.1021/bc050337w] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A broad range of applications requires access to water-soluble, bioconjugatable porphyrins. Branched alkyl groups attached at the branching site to the porphyrin meso position are known to impart high organic solubility. Such "swallowtail" motifs bearing a polar group (hydroxy, dihydroxyphosphoryl, dihydroxyphosphoryloxy) at the terminus of each branch have now been incorporated at a meso site in trans-AB-porphyrins. The incorporation of the swallowtail motif relies on rational synthetic methods whereby a 1,9-bis(N-propylimino)dipyrromethane (bearing a bioconjugatable tether at the 5-position) is condensed with a dipyrromethane (bearing a protected 1,5-dihydroxypent-3-yl unit at the 5-position). The two hydroxy groups in the swallowtail motif of each of the resulting zinc porphyrins can be transformed to the corresponding diphosphate or diphosphonate product. A 4-(carboxymethyloxy)phenyl group provides the bioconjugatable tether. The six such porphyrins reported here are highly water-soluble (> or =20 mM at room temperature in water at pH 7) as determined by visual inspection, UV-vis absorption spectroscopy, or 1H NMR spectroscopy. Covalent attachment was carried out in aqueous solution with the unprotected porphyrin diphosphonate and a monoclonal antibody against the T-cell receptor CD3epsilon. The resulting conjugate performed comparably to a commercially available fluorescein isothiocyanate-labeled antibody with Jurkat cells in flow cytometry and fluorescence microscopy assays. Taken together, this work enables preparation of useful quantities of water-soluble, bioconjugatable porphyrins in a compact architecture for applications in the life sciences.
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Kepczyński M, Nawalany K, Jachimska B, Romek M, Nowakowska M. Pegylated tetraarylporphyrin entrapped in liposomal membranes. Colloids Surf B Biointerfaces 2006; 49:22-30. [PMID: 16580183 DOI: 10.1016/j.colsurfb.2006.02.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2005] [Revised: 02/03/2006] [Accepted: 02/16/2006] [Indexed: 10/24/2022]
Abstract
A system of poly(ethylene glycol) bound tetraarylporphyrin entrapped in liposomal membranes was investigated. The interactions between the 5-(4-hydroxymethylphenyl)-10,15,20-tritolylporphyrin (Po) covalently attached to the poly(ethylene glycol) chain (PEG-Po), and phosphatidylcholine liposomes in the aqueous solution were studied. The adsorption of the investigated polymer to lipid vesicles was confirmed by measurements of dynamic light scattering and zeta potential. Experimental results demonstrate that the diameter of liposomes increased and the absolute value of the zeta potential decreased after addition of PEG-Po. The binding constants (K(b)) of Po chromophores to liposome in pH range from 5.2 to 9.0 were determined using fluorescence spectroscopy. The degree of binding was found to be pH-independent and the average value was 24.6 +/- 0.9 mg ml(-1). The acid-base properties of the porphyrin chromophores and their aggregation in an aqueous solution were also studied. pK values associated with imine-N protonation of the porphyrin core were found to be 2.59 and 0.68 at the ionic strength of 0.1 M. The equilibrium constant for dimerization, K(D), was found to be 5 x 10(3) M(-1).
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Affiliation(s)
- Mariusz Kepczyński
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland
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Abstract
Photodynamic therapy is a clinically approved treatment for cancer and noncancer diseases. This modality utilises light-activatable chemicals (photosensitising agents) to capture photons and use light energy for the production of cytotoxic reactive molecular species. Most photosensitisers that are in use clinically or in preclinical development are hydrophobic and tend to aggregate in the aqueous environment, which limits their delivery and photosensitising efficiency. Liposomal delivery of photosensitisers will often overcome or decrease these problems. In addition, as with chemotherapeutic agents, liposomal formulations of photo-sensitising agents may help to achieve better selectivity for tumour tissue compared with normal tissue. Over the past years, liposomal photosensitisers have emerged as therapeutic agents in many experimental studies, and have obtained approval for clinical applications. Recent progress in liposomal technology further opens up the possibility of generating more selectively targeted photosensitisers encapsulated in liposomes. This review will cover progress in the use of liposomal photosensitisers, summarise current liposomal formulations, and project future directions for the liposomal delivery of photosensitising agents.
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Affiliation(s)
- Bin Chen
- Dartmouth Medical School Department of Surgery, Lebanon, NH 03756, USA
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