Objective. Aim of this work was to create a stable liposomal dosage form of native hydrophobic antitumor compound from the group of indolocarbazoles-LHS-1208. Materials and methods. Quantitative analysis of the drug content in liposomes was determined by spectrophotometry with a standard sample at λ = 320 ± 2 nm. The encapsulation was investigated as the ratio of LHS-1208 concentration in the liposomal dispersion after extrusion through nylon membrane filters 0.22 µm "Pall" to concentration LHS-1208 in liposomal dispersions before filtration. pH of the liposome was determitaned by the method of potentiometry. The size of liposomes was evaluated by nanosizer. Cytotoxic activity was studied by MTT-test.
The composition of the photosensitizer and fluorocarbons with high oxygen capacity allows to increase the effectiveness of photodynamic therapy, which is shown on tumor cells. To achieve the solubility of photosensitizers in fluorocarbons, a number of fluorinated porphyrins were synthesized and their spectral characteristics were obtained. Fluorocarbon emulsions without a photosensitizer are inert for tumor cells of human colon adenocarcinoma. Fluorocarbon nanoemulsion with leader fluorinated porphyrin with fluoroaliphatic substituents accumulates in tumor cells and causes photoinduced necrosis due to peroxidation of membrane lipids. Perfluorocarbon nanoemulsions in combination with a dissolved fluorine phase photosensitizer are promising compositions for the photodynamic therapy of cancer.
Background. In connection with the prospect of the use of an analog of the hypothalamic hormone somatostatin synthesized by the laboratory of chemical synthesis Institute of experimental diagnostics and chemotherapy of FSBI «N.N. Blokhin Russian Cancer Research Center» and showed a high anti-tumor activity as a drug arises a need to establish an optimal technology of its receipt. In preliminary studies in a modelformulation for an analog of the hypothalamic hormone somatostatin selected liposome technological process of which has a series of specific steps comprising. Objective. Development of technology for obtaining liposomal formulation hypothalamic hormone somatostatin analogue. Materials and methods. Liposomes analog of the hypothalamic hormone somatostatin obtained by method Bengema in modification for hydrophobic substances. To reduce the diameter of the liposome are used methods extrusion, homogenization and ultrasonic. Analysis of the size of the liposomes was performed by correlation spectroscopy light scattering using nanosizer. The pH of the liposomal dispersion was determined by potentiometry. The quantitative content of the drug substance was determined by spectrophotometry using a standard sample with X (282 ± 3) nm and an alcoholic solution of empty liposomes as a reference solution. Amount of incorporated drug was calculated as the ratio of the concentration of drug in the liposome dispersion after filtration to the concentration of drug in the dispersion after preparation. Results and Conclusion. The hydrophobic nature of the substance causes an analog of the hypothalamic hormone somatostatin technological features of obtaining liposomal formulation. Since the step of forming a film of the lipid substance is dissolved in an organic solvent together with lipids, film is hydrated by a solution of cryoprotectant. Grinding liposomes an analog of the hypothalamic hormone somatostatin appropriate to be carried out using homogenization or extrusion methods, due to the high efficiency of these methods, the preservation stability of the liposomes and a high percentage of inclusion an analog of the hypothalamic hormone somatostatin, included in the liposomal bilayer. At the stage of separating the non-inclusion of substance an analog of the hypothalamic hormone somatostatin due to the insolubility of the substance in the water, you can use the filtering method, without the need for complicated procedures gel filtration, dialysis, etc. Furthermore the process of separating a substance not included can be combined with the sterilization of the liposome dispersion by selecting a particular filter material.
Short Communications Despite a wide range of chemotherapeutic drugs used in actual therapy of malignant tumours, the main limitation of use in clinical practice is the expressed toxicity of most of these. There existed a need to search, study and develop dosage forms of drugs with high antitumor activity and low expressed side effects. Such dosage forms are needed to deliver analogues of a peptide hormone of hypothalamus, somatostatin, which inhibited release of human growth hormone, thyrotropin, glucagon, insulin, and also suppressed proliferation of many normal and tumor cells [1]. Analogues of somatostatin such as octreotide and lantreotide are under clinical investigation [2]. Indications for their use in oncology are, endocrine tumours of digestive tract and pancreas and therapy of androgen-independent prostate cancer. Thus, synthesis of new analogues of the somatostatin group, investigation of the mechanisms of action of their antiproliferative activities, and development of dosage forms are the new directions of research in this field.
Введение. В ФГБУ «НМИЦ им. Н.Н. Блохина» Минздрава России синтезировано оригинальное N-гликозидное производное индолокарбазола ЛХС-1269 с углеводным остатком ксилозы, характеризующееся высокой противоопухолевой активностью в отношении ряда перевиваемых асцитных и солидных опухолей в экспериментах in vivo. В связи с гидрофобными свойствами субстанции ЛХС-1269 для создания инъекционной лекарственной формы предложен метод ее солюбилизации путем инкапсулирования в фосфолипидные везикулы − липосомы. Цель. Разработка состава модели липосомальной лекарственной формы для инъекционного введения производного индолокарбазола ЛХС-1269.
Introduction. The search for new antineoplastic agents in a series of indolo[2,3-a]-carbazole derivatives is an urgent and promising direction, since compounds with antitumor activity have been found in this class. In the chemical fusion laboratory, N.N. Blokhin National Medical Research Center оf the Ministry of Health of Russia has developed an original and effective method for the synthesis of glycosides of indolo[2,3-a]-pyrrolo[3,4-c]carbazoles, which makes it possible to synthesize derivatives of N-glycosides of indolo[2,3-a]carbazoles with different substituents in the heterocyclic parts including at the maleimide nitrogen atom and with different carbohydrate residues.The purpose of the study – the primary assessment of the antitumor activity of new derivatives of indolocarbazoles with a carbohydrate residue xylose in models of tumor growth mice.Materials and methods. The compounds studied at transplanted tumors of mice: the Lewis epidermoid carcinoma (LLC), colon cancer ACATOL, cervical cancer RSHM-5, breast adenocarcinoma CA-755. Studies were performed on immunocompetent mice: males and females of BDF1 hybrids (C57Bl/6 × DBA/2), females CBA/Lac and Balb/c. Compound solutions were prepared ex tempore and administered to the mice intraperitoneally at a dose of 60 mg/kg daily for five days. The antitumor effect was evaluated as to of tumor growth inhibition and increase of life span of the treated animals as compared with the control ones.Results. Eight compounds studied, containing D-xylose as a carbohydrate component and various substituents at the maleimide nitrogen atom, showed different degrees of antitumor activity. Two derivatives have been identified: N-[5,7-dioxo-12-(β-D-xylopyranosyl)-indole[2,3-a]pyrrolo[3,4-c]carbazol-6-il]benzamide (compound 4) and N-[5,7-dioxo-12-(β-D-xylopyranosyl)-5,7,12,13-tetrahydro-6H-indole[2,3-a]pyrrolo[3,4-c]carbazole-6-il]pyridin-2-carboxamide (compound 8), which showed high antitumor activity on 4 solid tumors of mice with a duration of effect of 12 days or more. The most pronounced antitumor effect was obtained in compounds 4 and 8 in RSHM-5 and Ca-755, tumor growth inhibition was amounted, respectively: in RSHM-5 – 68–82 % and 80–72 %; for Ca-755 – 57–62 % and 86–68 % (p <0.05).Conclusion. For further research, we chose the compound (N-[5,7-dioxo-12-(β-D-xilopiranosil)-5,7,12,13-tetrahydro-6H-indole[2,3-a] pyrrolo[3,4-c]carbazol-6-il]pyridin-2-carboxamide).