Oncolytic viruses (OVs) are a new class of targeted anticancer drugs with unique mechanisms of action. Oncolytic virotherapy has evolved from the use of in vitro-passaged strains (first generation) to genetically engineered viruses with increased selectivity (second generation) and, ultimately, to recombinant OVs expressing a transgene (third generation).The aim of the review was to analyze and summarize data on the current state of clinical research on OVs.A PubMed search identified 182 articles from 1997 to 2024 with 154 studies reporting data on 4,850 patients. We found that adenovirus (n = 44) is the most common OV in clinical trials with more than two-thirds (n = 108) using modified or recombinant viral backbones, and granulocyte-macrophage colony-stimulating factor (GM-CSF; n = 40) was the most common transgene. The most common tumors targeted were melanoma (n = 1,997) and gastrointestinal (GI; n = 916) cancers with the most common monotherapy received by intratumoral (n = 3,003) or intravenous (n = 1,318) delivery routes. The most common combination included chemotherapy (n = 54).Treatment-related adverse events included low-grade constitutional symptoms and local injection site reactions. Measurements of virus shedding were frequently performed, but many studies were limited to blood and tumor tissue analysis, using only polymerase chain reaction (PCR). Although most studies reported antiviral antibody titers (n = 101), only a few reported virus-specific T-cell responses (n = 23). Objective responses were recorded in 458 (9.4%) patients and disease control was achieved in 1,141 (23.5%) patients, although standard reporting criteria were used in only 60.4% of cases.These data provide an insight into the current state of clinical research on OVs and highlight potential areas requiring further investigation to better define the role of OVs in cancer treatment.

Hepatocellular carcinoma (HCC) is a prevalent form of primary liver cancer, ranking among the most common and lethal forms of oncological diseases. Transarterial chemoembolization (TACE) is one of the standard treatments for unresectable HCC, in which one of the key points is the embolization of tumor arteries, resulting in hypoxia that activates the HIF-1α signaling pathway. According to numerous literary data, bortezomib (BTZ) is capable of blocking the biological effects of HIF-1α. Based on the analyzed data, it can be assumed that the combination of bortezomib and TACE may lead to a synergistic effect, increasing the effectiveness of therapy and improving the prognosis for patients with unresectable HCC. In our work, we attempted to improve the antitumor efficacy of doxorubicin by combining it with an HIF-1α inhibitor in a model of hepatocellular carcinoma. During this study, it was established that the most effective suppression of tumor growth occurred in group 3, in animals with reduced blood flow and the administration of doxorubicin. The mean volume of tumor nodules was 395.33±95.70 mm3 (p<0.05), which was 2.1 times smaller than the mean volume in the control group, which was 830.56±144.86 mm3. In Group 2, in animals with reduced blood flow and the use of a combination of doxorubicin and bortezomib, the mean tumor node volume was 761.48 ± 117.95 mm³, which did not differ statistically from the volume of tumor nodes in the control group. Our findings indicate that a reduction in hepatic vascular blood flow in conjunction with doxorubicin exerts a pronounced inhibitory impact on the proliferation of intrahepatic tumor nodes. However, the introduction of bortezomib to this regimen does not result in the inhibition of tumor growth. Nevertheless, our results provide a rationale for a more comprehensive investigation of the mechanisms underlying the antitumor response or the reasons for its absence, as well as alternative candidates for HCC therapy. Keywords: liver cancer, hepatocellular carcinoma, bortezomib, HIF-1α, TACE, HepG2.

ОЦЕНКА ГЕМАТОЛОГИЧЕСКИХ И БИОХИМИЧЕСКИХ ПОКАЗАТЕЛЕЙ КРОВИ МЫШЕЙ ПРИ МНОГОКРАТНОМ ВВЕДЕНИИ 2-(1,1-ДИМЕТИЛ-1H-БЕНЗО[E]ИНДОЛИН-2-ИЛ)-5,6,7-ТРИХЛОР-1,3-ТРОПОЛОНА1 Головинов И.В., 1 Гончарова А.С., 1 Кузнецова Н.С., 1 Галина А.В., 1 Росторгуев Э.Е., 1 Ходакова Д.В., 1 Шульга А.А., 2 Гусаков Е.А., 3 Саяпин Ю

Purpose of the study. The purpose of this research was to investigate the effect of in vivo hypoxic conditions on the proliferative potential of HepG2 liver cancer cells. Materials and methods. Human liver cancer cells of the HepG2 line have been cultured. The HepG2 cell suspension was injected subcutaneously into mice in an amount of 5 × 10 6 to obtain a xenograft. Tumor nodes that had reached the required size were divided into fragments and transplanted into the orthotopic site. Balb/c nude mice with implanted HepG2 liver cancer xenograft were used in this experiment. The mice with tumor implanted in the liver were divided into two groups, intact and hypoxic. Mice from the second group underwent liver blood flow reduction by occlusion of the portal triad for 20 minutes. Tumor nodes were extracted for histological and immunohistochemical staining for proliferation marker Ki-67 on the 4th day after the procedures. The proportion of positively stained cells was calculated, and the results were statistically analyzed using the Statistica 10.0 software. Results. Orthotopic models of liver cancer in Balb/c Nude mice were obtained. Histological and immunohistochemical studies were carried out. Histological analysis showed that hepatocellular carcinoma is characterized by an average degree of differentiation. In the tissues of these xenografts, by using immunohistochemical analysis for the proliferation marker Ki-67, it was possible to identify statistically significant differences between the two groups, i.e. intact and the one with reduction of blood flow. The proportion of immunopositive cells was 65 [65–70] % and 19 [15–25] %, respectively. Conclusion. A tendency to decreased proliferative activity of tumor cells after hepatic blood flow reduction, i.e. hypoxia exposure, was demonstrated. Our data indicate that the proliferative activity of tumor cells is directly related to the microenvironment, and to the hypoxic environment in particular. Further study of the effect of hypoxia on the processes of growth and development of malignant tumors may contribute to a deeper understanding of the biological features of tumors and their treatment.

The efficiency of combinations of cytostatics cisplatin and adriamycin with antioxidant sodium 3-(3'-tert-butyl-4-hydroxyphenyl)propyl thiosulfate (TS-13), and nitric oxide (NO) donor NaNO2 was evaluated on two drug-resistant strains of leukemia P388 with changed redox-status of cells. Simultaneous use of both NO donor and TS-13 in combinations with the cytostatics did not increase the efficiency of therapy. In addition, antioxidant activity of TS-13, NaNO2, and their combinations was studied by the method of luminol-dependent chemiluminescence on the model systems with the use of the homogenized cells of sensitive strain and two drug-resistant strains of leukemia P388. It was shown that TS-13 and NO donor produced opposite effects: TS-13 decreased, while NO donor increased the content of free radicals in the model system. Combinations of antioxidant TS-13 and NO donor should be used with consideration for the redox-status of tumor treated.

Purpose of the study. This work was to assess the engraftment and growth dynamics of breast cancer xenografts during orthotopic and subcutaneous injection using various types of biological material, as well as to develop an adequate model of breast cancer for further research.Materials and methods. We used a disaggregated fragment of a tumor obtained from the patient, a certified breast cancer cell line VT20 – human breast carcinoma; a primary human breast carcinoma cell line. Female immunodeficient mice of the Balb/c Nude line in the amount of 36 animals were used as recipient animals. The subcutaneous and orthotopic models of breast cancer were developed in this project. Tumor growth was observed for 28 days from the moment of injection and tumor nodes were measured 2 times a week until the end of the experiment. Results were assessed using medians and percentiles. The nonparametric Mann-Whitney test was used to assess the significance of differences.Results. The dynamics of the growth of tumor cells when injected into various sites was determined in the process of this work. The most successful in terms of a subcutaneous injection was the injection of tumor cells of the certified VT20 line. By the end of the experiment, the median tumor node of this group was 100.32 mm³. The analysis revealed tumor dynamics with orthotopic injection of tumor material, and the median volume of the tumor node in the group with the passport culture cell VT20 and the primary culture cell reached the same value – 149.22 and 148.25. mm³. It was found that both the cell line and the cell suspension were injected into tumor nodes that reached a significantly larger volume when injected orthotopically.Conclusion. We have obtained a tumor model of breast cancer using various methods of material implantation and with the possibility of further use in testing new pharmacological substances.

ОЦЕНКА ТОКСИКОМЕТРИЧЕСКИХ ПОКАЗАТЕЛЕЙ ПРОИЗВОДНОГО БЕНЗИМИДАЗОЛА ДЛЯ ЛИНЕЙНЫХ МЫШЕЙ С57/BL6

СРАВНИТЕЛЬНАЯ ОЦЕНКА МЕТОДОВ СОЗДАНИЯ ОРТОТОПИЧЕСКОЙ МОДЕЛИ РАКА ПЕЧЕНИКечерюкова Т.М. 1 , Гурова С.В. 1 , Гончарова А

Glioblastoma (GBM) is the most malignant and the most common primary tumor of the central nervous system. During the last several years GBM has been classified and managed according to the World Health Organization (WHO) criteria which subdivide it into primary and secondary GBM. As it is suggested, GBM originates from glial cells and has a diffuse growth pattern, but its etiology and pathophysiology are poorly investigated up to date. Its rapid progression and anatomical location in the brain often limits the effectiveness of therapeutic interventions. Despite all scientific and technological advances, GBM remains an incurable disease with a median survival of approximately 18 months. Standard treatment options involving maximal safe resection of the tumor followed with radiotherapy and chemotherapy do not provide satisfactory Results.Better understanding of the molecular pathology of GBM and its associated signaling pathways has opened up possibilities for new treatments for newly diagnosed and relapsing tumors. A multitargeted therapeutic approach using compounds capable of inhibiting more than one specific molecular target is a promising alternative to conventional therapies.Currently, specialists study such innovative treatment options as small molecule inhibitors aimed at signaling pathway disruptions, immunotherapy, including checkpoint inhibitors, oncolytic vaccines, CAR T-cell therapy, and drug delivery systems. In terms of an innovative approach, the elaboration of targeted drug delivery systems is of particular interest, since this strategy looks the most promising due to its ability to increase the bioavailability and effectiveness of both standard and newly tested agents. This review discusses results of preclinical and clinical studies of innovative therapeutic approaches, their advantages and disadvantages. An interdisciplinary approach is expected to be able to combine the results of cutting-edge research in this area and to provide novel promising therapeutic strategies for patients with GBM.

The efficiency of 3 protocols of cryopreservation of tumor tissue obtained from patients with malignant formations of the gastrointestinal tract: esophagus, stomach, large intestine was evaluated. The experiment was performed on 90 Balb/c Nude mice. After 90 days from the moment of freezing of tumor nodes, the samples were thawed and implanted in animals, the number of surviving implants was noted and the beginning of growth of tumor nodes in animals was recorded. For cryopreservation of xenografts of human esophageal and colon cancer, it is possible to use protocols 2 and 3 tested by us, where the key feature is the slow freezing of samples. For the tumor material of the stomach, it is necessary to develop other methods of preservation, due to the low efficiency of the methods considered in the work.

We studied an effect of the portal triad blood flow reduction on liver enzymes, the organ status and survival of laboratory mice. The study included Balb/c mice divided into groups (n=6 for each group): group 1 - controls, blood and liver were collected; group 2 - liver blood flow reduction for 20 minutes, blood and liver were collected 2 hours after the procedure; group 3 - liver blood flow reduction for 20 minutes, blood and liver were collected 24 hours after the procedure; group 4 - liver blood flow reduction for 20 minutes, and the follow-up during the next 14 days to assess the survival. The blood flow was reduced by occlusion of the portal triad: the animals underwent laparotomy, then the portal triad was isolated and a needle with suture material was brought under it; weights were attached to the ends of the suture material, and the vessels were occluded due to the tension of the ligature. The levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in both groups with reduced blood flow were statistically significantly higher than in the control group (p<0.05), and also statistically significantly higher in the group with blood sampling 24 hours after reperfusion, compared to the group with blood sampling 2 hours after reperfusion (p<0.05). Histological examination showed signs of ischemic damage in tissues, and an increase in the number of vessels in liver samples of animals with blood flow reduction, compared to the control. The animal survival after the procedure was over 80%, which was satisfactory, but nevertheless indicated the need for such a number of animals that will allow statistical processing of the results even if some animals die. The results of the study demonstrated the model as an important tool for the study of ischemic and hypoxic-associated pathological liver states.

Purpose of the study . Creation of a transplantable orthotopic PDX model of gastric cancer in Balb/c Nude immunodeficient mice using implantation and injection. Materials and methods . Two methods, that are injection and implantation, were used to create an orthotopic PDX model of human gastric cancer. The first method involved injections of a suspension of a mechanically disaggregated patient's tumor after filtration into the gastric wall of Balb/c Nude mice. For the second method, small fragments (3 × 3 × 3 mm) of patients' tumors were implanted in the gastric wall of mice along the greater curvature with a dissection of the serous muscular layer. Results. Control laparotomy in Balb/c Nude immunodeficient mice showed a successful engraftment of the tumor material at the 1st and 3rd procedures when using the implantation method for the creation of a PDX model of gastric cancer. The injection method was ineffective, and no models were created. The histological type of the obtained PDX models was compared to the type of the donor tumor by histological examination (hematoxylin and eosin staining). The tumor grade remained stable and did not change during xenograft passage, which showed that the obtained model was identical to the histotype of the donor tumor. Conclusion. The presented implantation method for the model creation results in effective tumor engraftment. The developed model can be used to test the effectiveness of anticancer or antimetastatic drugs, for studying the functions of biomarkers, or in assessing the microenvironment of a gastric cancer.

Purpose of the study. Evaluation of the expression of immunohistochemical tumor markers Ki-67, b-catenin, Bcl-2, P53, connexin 32 and connexin 43 when using 2-(6,8-dimethyl-5-nitro-4-chloroquinoline-2-yl)-5,6,7-trichloro-1,3-tropolone in mice with xenographs of squamous cell lung cancer.Materials and methods. Subcutaneous PDX models of human squamous cell lung cancer were created in immunodeficient BALB/c Nude mice. A fragment of the patient’s tumor (3 × 3 × 3 mm) was implanted subcutaneously in the right thigh of a previously anesthetized mouse. 200 μl of 2-(6,8-dimethyl-5-nitro-4-chloroquinoline-2-yl)-5,6,7-trichloro-1,3-tropolone was administered orally using a probe in 12 doses once every 3 days. All animals were divided into groups depending on the tropolone doses: experimental groups 2–5 with doses of 0.0055, 0.055, 0.55 and 2.75 mg/g, respectively. The control group received 1 % starch gel which was tropolone carrier. The animals were euthanized 36 days after the start of the substance administration, and the tumor tissue was isolated and prepared for the IHC study according to the standard protocol. IHC reactions were performed using antibodies for Ki-67, b-catenin, Bcl-2, P53, connexin 32 and connexin 43.Results. Higher tropolone doses were associated with decreased expression of Ki-67, b-catenin, and the Bcl-2 protein, but increased expression of the P53 protein. The dosage of tropolone and expression of connexin 43 were directly proportional.Conclusion. Immunohistochemical analysis of expression of proteins in PDX models of human squamous cell lung cancer when using 2-(6,8-dimethyl-5-nitro-4-chloroquinoline-2-yl)-5,6,7-trichloro-1,3-tropolone showed the changes indicating its antitumor efficacy and suggesting a possible mechanism of action based on the activation of apoptosis.

МОДЕЛИ РАКА ПЕЧЕНИ IN VIVOГурова С.В. 1 , Кечерюкова Т.М. 1 , Гончарова А.С. 1 , Колесников Е.Н

-The visualization of microfluidic chips is considered to study the morphology of the microfluidic channel surface and estimate the quality of 3D-printing technology based on digital light processing. Visualization is performed by X-ray microtomography using different iodine-based contrast agents and by scanning electron microscopy. It is shown that X-ray microtomography visualization makes it possible to control the quality of device printing relative to the geometrical parameters of the models specified at the device prototyping stage, as well as to visualize a 3D model of microfluidic channels and surface morphology. The spatial resolution of scanning electron microscopy exceeds the print pixel size and makes it possible to clarify the presence of local defects caused by uneven solidification of the resin during sample washing.