Photodynamic cancer therapy

Davydenko MO, Radchenko EO, Yashchuk VM, Dmitruk IM, Prylutskyy YI, Matishevska OP, Golub AA (2006) Sensibilization of fullerene C60 immobilized at silica nanoparticles for cancer photodynamic therapy. J Molec Liq 127 145-147. 

Abstract The supramolecular composites containing fullerenes C60 immobilized at nanosilica were used for the design of the molecular systems that can be an effective agent in cancer photodynamic therapy (PDT). In particular, it was shown that photoexcited fullerene C60-containing composites decrease viability of transformed cells, intensify the process of lipid peroxidation (LPO) in cell membranes and accumulation of low-molecular weight DNA fragments, and also decrease the activity of electron-transport chain of mitochondria. 

Phototherapy is the generic term covering therapies which use light either with or without a sensitiser. Those that do not require a sensitiser use the natural chromophores within the tissue to perform this function e.g. treatment of vitamin D deficiency in rickets, and neonatal jaundice). Those that do use an added sensitiser include photochemotherapy (largely psoriasis and skin disorders) and photodynamic therapy (currently mainly cancer). Photodynamic therapy is differentiated from photochemotherapy by its additional requirement for the presence of oxygen at molecular or ambient levels.In this text we will deal only with photodynamic therapy since, at the present time, this is the main driving force in phototherapy. ° ... 

Le Garrec D, TaiUefer J, Van Lier JE, Lenaerts V, Leroux JC (2002) Optimizing pH-respon-sive polymeric micelles for drug delivery in a cancer photodynamic therapy model. J Drug Target 10 429 37... 

Photodynamic therapy has also been applied to the treatment of early gastric cancer. Photodynamic therapy appears to be superior to other modalities including thermal laser for this indication. This is particularly true for lesions with a depth of invasion estimated to be limited to the submucosa and where the margins of the lesion are unclear [38]. 

The interaction of artificial metal ions/complexes with peptides/proteins [11], nucleic acids/DNA [12,13], enzymes [14], steroids [15] and carbohydrates [16] forms a bridge between natural and artificial macromolecular metal complexes. Biometal-organie chemistry concentrates on such complexes [17]. The reason for the increasing interest in this field lies in medical applications of metal complexes (cancer, photodynamic therapy of cancer, immunoassays, fluorescence markers, enantioselective catalysis, template orientated synthesis of peptides, etc.). Figure 2-4 presents an overview of metals in medicine [18]. Some examples are given below. 

Cyanines. Photochemical and photophysical studies of cyanine dyes are an important and up-to-date research domain, due to their use in several relevant applications, such as black and white and color photography, laser dyes, potential sensitizers in cancer photodynamic therapy, and also devices for optical storage of data [88]. 

Platinum Cancer, photodynamic therapy, microbial infections, viral infections including AIDS [79-82]... 

Works.that have recently appeared regarding the use of microwave radiation for synthesis of tetraarylporphyrins, phthalocyanines and their metallocomplexes with Er and Gd in the dimethylacetamide medimn in presence of dry lithimn chloride [5, 6], induced us to cany out similar syntheses on the example of TPP [7] and 5,10,15,20-tetrakis(3-methoxyphenyl)porphyrin. This porphyrin is interesting due to fact that on the basis of its dihydroderivative Bormet [8] created a drag Foscan, which is used for the cancer photodynamic therapy. Octabromderivative FFP-Br was synthesized from the TPP copper complex [9]. 

The development of so-called photodynamic therapy uses lasers for treatment of cancer. The patient is injected with a substance called hematoporphyrin derivative [68335-15-9] which is preferentially localized in cancerous tissues. The patient is later irradiated with laser light, often with a dye laser at a wavelength around 630 nm. The light energy catalyticaHy photooxidizes the hematoporphyrin derivative, releasing materials which kill the nearby cancerous tissue. Normal tissue which did not retain the chemical is not harmed. Photodynamic therapy offers promise as a new form of cancer treatment. 

Nitro ilkenes derived from galdctose or other carbohydrates are converted directly into pyrroles siibsdnited v/ith such carbohydrates at the fi-posidon. They are important precursors for water-soluble porphyrins fEq. 10.29. Such kmds of porphyrins are good candidates for photodynamic therapy of cancer and have been extensively snithed. 

The most important application for singlet oxygen generators (SOGs), namely the anti-cancer treatment known as photodynamic therapy (PDT), is described elsewhere in this series (see Chapter 9.22). However, SOGs are also being evaluated in other areas, such as hard surface disinfectants, soaps and washing powders,73 and insecticides.74,75... 

Porphyrins 21 are the backbone of major players in life cycles—cytochromes (Scheme 8). There are three types of cytochromes, classified by their color, or more precisely by their long-wavelength absorption band, as a (600 mn), b (563 nm), and c (550 nm). They are protein conjugates of a porphyrin complex with iron(II), which is a coenzyme called heme (22). In plants, porphyrins form a complex with magnesium-(II) chlorophylls a and b (23), vital in photosynthesis. Porphyrin derivatives are used in photodynamic therapy for dermatological diseases such as psoriasis, and for skin or subcutaneous cancer.5c-e... 

In the photodynamic therapy of cancer, for example, macrocyclic tetrapyrrholic compounds named porphyrins are used. Porphyrin-containing wastewaters can negatively affect the aquatic ecosystems (plants and fish population), even in very small concentrations. Recent studies present a method adequate for the advanced purification of medical wastewaters containing such porphyrins [94],... 

Singlet Oxygen and Photodynamic Therapy for Cancer Treatment... 

Kopelman R, Lee Koo Y, Philbert M, Moffat BA, Ramachandra Reddy G, McConville P, Hall DE, Chenevert TL, Bhojani MS, Buck SM, Rehemtulla A, Ross BD (2005) Multifunctional nanoparticle platforms for in vivo MRI enhancement and photodynamic therapy of a rat brain cancer. J Magn Magn Mater 293 404-410... 

Keywords Photodynamic therapy Photosensitizer Photochemistry Reactive oxygen species Cancer Microorganism Infection... 

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