Relevance. The search for new antitumor drugs and their selective delivery directly to the tumor site is an important task of modern oncology. For these purposes, currently, the use of various nanoparticles as carriers of medicinal substances is of great importance. The pathomorphological features of tumor cells under the action of salinomycin and nanodiamonds have not been studied enough. The aim of the work was to study the pathomorphological features of the tumor in mice with transplanted Lewis lung carcinoma, who were treated with the ionoform antibiotic salinomycin and a combination of salinomycin with nanodiamonds. Material and methods. 20 mice were divided into 4 groups. 1 – control group; 2 – mice received salinomycin; 3 – salinomycin and nanodiamonds; 4 – nanodiamonds. A morphometric study of histological and immunohistochemical tumor preparations stained for PCNA was carried out. Results. Salinomycin is established to have an antineoplastic action. The use of nanodiamonds did not significantly affect the morphofunctional characteristics of Lewis lung carcinoma and did not change the antitumor activity of salinomycin. Conclusion. Salinomycin has an antitumor effect and requires further research.

We studied the effectiveness of photodynamic therapy with the photosensitizer Photoran E6 on the model of rat sarcoma M-1 positive for mutant p53 gene. Experiments showed that Photoran E6 exhibits high antitumor activity in photodynamic therapy of solid tumor of the connective tissue. Photodynamic therapy carried out during the optimal period after injections of Photoran E6 with the determined parameters of laser exposure allows achieving the maximum inhibitory effect on sarcoma M-1: 100% cured animals. Immunohistochemical study revealed no live tumor cells with expression of the mutant p53 protein in areas of photodynamic exposure.

The purpose of the work was to study the ability of the NOS inhibitor T1023 to prevent late radiation injuries. Methods: the effects of T1023 (75 mg / kg, once i.p. 30 minutes before the irradiation) on the development of post-radiation pulmonitis and pneumofibrosis in rats with thoracic exposure to g-radiation at a dose of 12.5 Gy were studied histopathologically and morphometrically. The results of the studies showed that there wasn’t a significant objective effect of T1023 on the development of early radiation-induced lung injuries (9 weeks after irradiation). But it prevented late radiation induced lung injuaries (26 weeks after irradiation) – there were a significant lesser pathomorphological manifestations of post-radiation pulmonitis, proliferation of connective tissue and the development of fibrotic changes in the lung parenchyma. At this stage, the action of T1023 clearly contributed to the preservation of the normal histostructure of the lungs, reducing by 40% the content of compaction zones in the parenchyma. The ability of the NOS inhibitor T1023 to significantly limit the development of lungs late radiation reaction confirms the promise of further development of this compound as a means for prevention radiation therapy complications.

Цель исследования - изучение механизмов противоопухолевой активности ингибитора NOS Т1023 и оценка перспективности его дальнейшей разработки. Методика. В качестве опухолевой модели использована эпидермоидная КЛЛ, штамм которой получен из банка опухолевых материалов ФГБУ РОНЦ им. Н.Н. Блохина и поддерживался на самцах мышей C57BL6j. КЛЛ трансплантировали самцам мышей F1 (CBA´C57BL6j) путем подкожного введения 1,5×106 клеток карциномы в 0,1 мл суспензии на основе среды 199 в область латеральной поверхности правого бедра. Для сравнительной оценки противоопухолевой эффективности использовали ингибитор NOS под шифром Т1023, синтезированный в лаборатории радиационной фармакологии МРНЦ им. А.Ф. Цыба, и VEGF-ингибитор бевацизумаб (БВЗ). Животным первой опытной группы ежедневно, со 2 по 20 сутки вводили соединение Т1023 (60 мг/кг, в/б); второй опытной группы - трижды, на 2, 5 и 10 сут вводили БВЗ (12 мг/кг, в/б); третьей опытной группы - по этим схемам и в таких же дозах вводили и Т1023, и БВЗ (при комбинированном применении Т1023 вводили через 4 ч после введения БВЗ). Контрольным животным в качестве плацебо со 2 по 20 сутки вводили 0,9% раствор натрия хлорида (0,2 мл, в/б). Противоопухолевые эффекты оценивали, сравнивая размеры опухолевых узлов, длительность задержки роста и индекс торможения роста опухоли у контрольных и опытных животных. Гистологические методы исследования включали иммуноокрашивание на PCNA, CD31, пимонидазол и морфометрический анализ микроскопических изображений. Результаты сравнительных исследований показали, что соединение Т1023 и VEGF-ингибитор бевацизумаб (БВЗ) оказывают однонаправленное влияние на карциному легких Льюис (КЛЛ), сопровождающееся торможением роста и подавлением метастазирования неоплазии. Воздействие и Т1023, и БВЗ вызывало снижение содержания сосудов в перитуморальных зонах и в «горячих точках» ангиогенеза, усиливало гипоксию паренхимы КЛЛ и стимулировало апоптоз опухолевых клеток. При комбинированном применении Т1023 и БВЗ их антинеопластическая эффективность в отношении ингибирования ангиогенеза и девитализации опухолевых клеток соответствовала аддитивному действию. Заключение. Результаты позволяют предполагать, что основой противоопухолевой активности Т1023 является антиангиогенное действие и свидетельствуют о перспективности применения ингибиторов NOS в ангиостатической терапии солидных злокачественных новообразований в сочетании с имеющимися антинеоваскулярными средствами. The aim. Study of mechanisms of NOS inhibitor T1023 antitumor activity and estimation of its prospects for further development. Methods. Epidermoid Lewis lung carcinoma (LLC) from N.N. Blokhin NMRCO bank of tumor materials was used as a tumor model. Maintenance of tumor cell culture was provided by intramuscular injection of tumor cells suspension to C57BL6j mice every 14 days. Then LLC cells were transplanted to male F1 mice (CBA´C57BL6j) by subcutaneous injection of 1,5×106 cells in 0,1 ml of 199 medium into the lateral surface of the right hip. Comparative studies of antitumor efficacy were carried out using NOS inhibitor T1023, synthesized in the laboratory of radiation pharmacology of A.F. Tsyb MRRC, and VEGF inhibitor Bevacizumab (BVZ). Mice from the first experimental group were injected intraperitoneally (ip) with compound T1023 at dose 60 mg / kg from day 2 to 20; animals from the second experimental group were treated with BVZ at dose 12 mg / kg ip at days 2, 5 and 10; the third experimental group received T1023 in combination with BVZ according to these schemes and at the same doses (T1023 was administered 4 hours after administration of BVZ). Mice from the control group received 0,9% sodium chloride solution (0,2 ml, ip) as a placebo daily from 2 to 20 days. Antitumor effects were assessed by comparing the tumor size, duration of tumor growth delay and the index of tumor growth inhibition in control and experimental groups. Histological examination methods included immunostaining on PCNA, CD31, pimonidazole and morphometric analysis of microscopic images. Results. Comparative studies have shown that compound T1023 and VEGF inhibitor Bevacizumab (BVZ) have unidirectional effects on Lewis lung carcinoma (LLC), accompanied by growth inhibition and suppression of metastasis of neoplasia. The effect of both T1023 and BVZ caused a decrease in vascular content in the peritumoral zones and in the “hot spots” of angiogenesis, increased the hypoxia in the LLC parenchyma, and stimulated apoptosis of tumor cells. The combined use of T1023 and BVZ, caused the antineoplastic efficacy against inhibition of angiogenesis and devitalization of tumor cells which was estimated as additive effect. Conclusion. The results suggest that the basis of antitumor activity of T1023 is the anti-angiogenic effect and indicate the prospects of using NOS inhibitors in the angiostatic therapy of solid malignant neoplasms in combination with available anti-neovascular agents.

The results of a complex morphofunctional study with markers of proliferation (PCNA and Ki-67), angiogenesis (CD31 and CD34), and structural integrity of mesenchymal cells (vimentin) suggest that the pool of primordial follicles was well preserved in vitrified ovarian tissue and that viability of its cellular components can be rapidly restored during incubation at 37°C within 4 h after thawing.

Радиосенсибилизирующее действие мезенхимальных стволовых клеток человека при локальном воздействии -излучения на саркому М-1 крысСеванькаева Л.Е., Южаков В.В

The study of the functional morphology of rat sarcoma M-1 after photodynamic therapy using bacteriopurpurinimide disulfide derivative (disulfide-BPI) as a photosensitizer is described. The research methods included immunohistochemistry for PCNA and CD31, evaluation of mitotic activity and apoptosis of tumor cells, as well as computer analysis of microscopic images. Photoinduced antitumor effect was shown to be due to the destruction of sarcoma M-1 vascular bed, the rapid inhibition of proliferative activity and devitalization of tumor cells by apoptosis and necrosis. It is reasonable to suppose that in the early stages after photodynamic therapy destruction of the microvasculature and photocytostatic shock of tumor cells with subsequent development of necrosis are caused by direct influence of the light flux on sensitized cellular elements in parenchyma and stroma of tumors. The efficiency of photodynamic therapy with the novel photosensitizer is determined by the sequence of destructive and inflammatory changes in tumor parenchyma and surrounding tissues, as well as repopulation potential of tumor cells survived after treatment.

Background : In recent years, the method of photodynamic therapy (PDT) has been increasingly used in clinical oncology. Three non-toxic components play a key role in realization of the anti- tumor effect of PDT: a photosensitizer (PS), local irradiation of the tumor with light/laser of a certain wavelength corresponding to the sensitizer absorption peak, and oxygen. The highly reactive biological oxidants formed during photochemical reactions exert a destructive effect on cells and tumor vasculature with subsequent activation of the immune response. Efficiency of PDT is determined by the level of PS accumulation in tumors, as well as by its photophysical parameters and photochemical activity. To create a new PS, natural chlorophylls and their derivatives with intense absorption in the long-wave region of the spectrum are of particular interest. Aim : To study the efficacy and mechanism of PDT action (using a conjugate containing two molecules of dipropoxy-bacteriopurpurinimide with a cystamine residue as a PS) on the growth and functional morphology of transplanted solid connective tissue tumor. Materials and methods : The study was carried out in female white outbred rats with subcutaneously implanted sarcoma M-1. PS was injected to rats of the experimental group intraperitoneally. PDT was performed during the maximal index of tumor/ healthy tissue contrast after the administration of the PS. The criterion of PDT efficacy was a change in the tumor growth/regression coefficient. The research methods included immunohistochemistry for PCNA and CD31, evaluation of mitotic activity and apoptosis of tumor cells, as well as computer analysis of microscopic images. Results : After PDT with the new PS, a 16-fold decrease of growth coefficient of tumor nodes was registered. The photo-induced antitumor effect was shown to be due to destruction of sarcoma M-1 vascular bed, rapid inhibition of proliferative activity and devitalization of tumor cells. At early stages after PDT, destruction of the microvasculature and photo-cytostatic shock of tumor cells with subsequent development of necrosis appears to be caused by direct influence of the light flux on sensitized cellular elements in tumor parenchyma and stroma.  Conclusion : The final result of PDT is determined by the sequence of destructive and inflammatory changes in the tumor parenchyma and surrounding tissues, as well as by a proliferative potential of malignant cells surviving after treatment. The surviving tumor cells, which determine the recurrent growth of neoplasms after PDT, are still present, maybe due to an insufficient concentration of the sensitizer in certain weakly vascularized areas of sarcoma M-1.

Background: In recent years, the method of photodynamic therapy (PDT) has been increasingly used in clinical oncology. Three non-toxic components play a key role in realization of the anti- tumor effect of PDT: a photosensitizer (PS), local irradiation of the tumor with light/laser of a certain wavelength corresponding to the sensitizer absorption peak, and oxygen. The highly reactive biological oxidants formed during photochemical reactions exert a destructive effect on cells and tumor vasculature with subsequent activation of the immune response. Efficiency of PDT is determined by the level of PS accumulation in tumors, as well as by its photophysical parameters and photochemical activity. To create a new PS, natural chlorophylls and their derivatives with intense absorption in the long-wave region of the spectrum are of particular interest.Aim: To study the efficacy and mechanism of PDT action (using a conjugate containing two molecules of dipropoxy-bacteriopurpurinimide with a cystamine residue as a PS) on the growth and functional morphology of transplanted solid connective tissue tumor.Materials and methods: The study was carried out in female white outbred rats with subcutaneously implanted sarcoma M-1. PS was injected to rats of the experimental group intraperitoneally. PDT was performed during the maximal index of tumor/ healthy tissue contrast after the administration of the PS. The criterion of PDT efficacy was a change in the tumor growth/regression coefficient. The research methods included immunohistochemistry for PCNA and CD31, evaluation of mitotic activity and apoptosis of tumor cells, as well as computer analysis of microscopic images.Results: After PDT with the new PS, a 16-fold decrease of growth coefficient of tumor nodes was registered. The photo-induced antitumor effect was shown to be due to destruction of sarcoma M-1 vascular bed, rapid inhibition of proliferative activity and devitalization of tumor cells. At early stages after PDT, destruction of the microvasculature and photo-cytostatic shock of tumor cells with subsequent development of necrosis appears to be caused by direct influence of the light flux on sensitized cellular elements in tumor parenchyma and stroma. Conclusion: The final result of PDT is determined by the sequence of destructive and inflammatory changes in the tumor parenchyma and surrounding tissues, as well as by a proliferative potential of malignant cells surviving after treatment. The surviving tumor cells, which determine the recurrent growth of neoplasms after PDT, are still present, maybe due to an insufficient concentration of the sensitizer in certain weakly vascularized areas of sarcoma M-1.

A comprehensive histological and morphofunctional analysis with the use of markers of proliferation (PCNA and Ki-67), angiogenesis (CD31 and CD34) and structural integrity of cells of mesenchymal origin (vimentin) shows good preservation of the pool of primordial follicles in vitrified ovarian tissue and the rapid recovery of the viability of its cellular components after thawing.

Immunohistochemical and morphometric analyses have demonstrated long-distance stimulatory effects of the natural volatile components of the urine of intact mice on the proliferationof splenic lymphocytes in mice exposed to a single total γ-irradiation in a dose of 1 Gy. These results are in line with the data on stimulation of the humoral immune response to thymusdependentantigen in irradiated mice exposed to urine specimens of intact animals.

The effectiveness of fractionated exposure to gamma- and neutron radiation in their separate and combined use on the growth and functional morphology of mutant p53 sarcoma M-1 in rats was studied. Investigation techniques included immunostaining of PCNA and mutant p53 expressing cells, determination of mitotic activity and apoptotic death of tumor cells, as well as computer analysis of microscopic images. The antitumor efficacy of different types of radiation is shown to be determined by different levels of apoptosis induction, reduced proliferation and cellularity. Neutron radiation of the impulse generator has a marked damaging effect on the vasculature and the development of tumor necrosis. Fractionated irradiation at equal daily doses led to the decrease in the relative effectiveness of radio-inactivation of tumor cells. After 9 fractions of irradiation, the calculated value of the RBE of fast neutrons normalized to the input dose of 1 Gy by the coefficient of tumor growth inhibition, a reduced proliferative activity of PCNA and induced apoptosis of tumor cells was 3.4, 3.7 and 3.1, respectively. In the mode of daily superfractionation with splitting the dose in two fractions, the effectiveness of the combined exposure corresponded to the additive effect of gamma- and neutron radiation with a tendency toward synergism. There are reasons to believe that high resistance of sarcoma M-1 to the ionizing radiation impact is due not only to a fraction of hypoxic cells, but also the mutant status of p53 gene.

We studied the effect of transplantation of human stem cells from various tissues on reparative processes in the brain of rats with closed craniocerebral injury. Combined treatment with standard drugs and systemic administration of xenogeneic stem cells had a neuroprotective effect. The morphology of neurons rapidly returned to normal after administration of fetal neural stem cells. Fetal mesenchymal stem cells produced a prolonged effect on proliferative activity of progenitor cells in the subventricular zone of neurogenesis. Adult mesenchymal stem cells had a strong effect on recovery of the vascular bed in ischemic regions.

Studies of the effects of vilon and epithalon on functional morphology of the thymus, spleen, and duodenum in intact rats and rats exposed to single whole-body γ-irradiation in a dose of 6 Gy showed that vilon stimulated proliferative activity of thymocytes and enhanced proliferative potential of stem cells in the intestine, thus stimulating the postradiation recovery of critical organs. Epithalon decelerated metabolic processes in the duodenal mucosa and suppressed hemopoiesis and lymphopoiesis in the spleen.

The study was concerned with growth of sarcoma M-1 and basic morphological characteristics of proliferative activity of cells of this strain as well as apoptosis of cells at different stages of tumor progression in rats before and after a single gamma irradiation at 30 Gy. At the parenchymal periphery which determines tumor growth, the PCNA index of proliferating cells was 76.5%; spontaneous cell death--0.28%. During post-irradiation period, the sarcoma PCNA index fell to 62.3% while the apoptotic index rose five-fold. These findings support the concept of radiation-induced apoptosis being a major pathogenetic factor responsible for effectiveness of radiotherapy of tumors. Indirect evidence on PCNA immunostaining suggested that synthesis of this cyclin is sensitive to the level of oxygen input in the cell, yet it offers sufficient resistance to gamma-radiation.