Purpose of the study. The investigation is aimed to provide a systematic comparison of different contrasting methods for in vivo micro-CT diagnostic of orthotopic colorectal cancer models extracted by ortotopic implantation into the caecum of immunocompromised mice BALB/c Nude lines.Materials and methods. BALB/c Nude (N = 25) female mice were implanted by transplanted human colorectal cancer strain into the cecum. 20 days after the implantation mice were administered with iodine-based contrast agent Optiray by means of different administration method (intravenously, per os, intraperitoneally, per rectum) and micro-CT scans have been registered via Quantum GX2 tomograph. Measurement of tumor nodes was performed both by means of estimation from micro-CT images via RadiAnt DICOM Viewer software and by means of explicit measurements using calipers upon laparotomy and posthumously. At the last stage of the study, the animals were euthanized by cervical dislocation. The tumors were excised, measured with a caliper and placed in 10 % formalin for the standard histological analysis according to the standard methods.Results. The average volumes of tumor xenografts in animals with intravenous, oral, and intraperitoneal contrast administration measured at micro-CT were 53.7 ± 5.2 mm3, 52.7 ± 6.4 mm3 and 63.6 ± 5.6 mm3 respectively; measured at laparotomy – 43.0 ± 5.5 mm3, 44.5 ± 5.4 mm3 and 58.5 ± 5.5 mm3 respectively; measured post-mortem – 55.2 ± 6.6 mm3, 53.2 ± 8.8 mm3 and 65.9 ± 3.8 mm3 respectively. The average volumes of tumor xenografts isolated post-mortem in these groups were comparable with the values shown at micro-CT, but larger than the volumes measured at laparotomy.Conclusion. The results obtained demonstrated that intravenous, peroral and intraperitoneal administration techniques provide the best visualization of laboratory rodents pathological tissue upon in vivo micro-CT diagnostics and thus are preferred.

Purpose of the study. Evaluation of the antioxidant status and DNA damage in tissues of subcutaneous xenografts of non-small cell lung cancer and in peritumoral tissues created using the A549 and H1299 cell cultures.Materials and methods. The study included 35 intact male Balb/c Nude immunodeficient mice. Cell lines A549 and H1299 were used as transplantable tumor biomaterial. A CDX model was created in accordance with the protocol for supratentorial injections (Ozawa T., James C. D., 2010) adapted for this experiment. Growth rates were controlled and intracranial xenografts were visualized using a high-resolution micro-CT system. The activity of catalase and superoxide dismutase was determined with non-denaturing electrophoresis in 8 % and 12 % polyacrylamide gel. The concentrations of sulfhydryl groups were determined according to Ellman. The DNA damage in lymphocytes was determined by the comet assay.Results. The experiment resulted in the creation of models of brain tumors characterized by intracranial growth pattern in 100 %. The activity of catalase in the studied lysates of intracranial xenografts, peritumoral tissue and healthy tissues of tumor-bearing animals in all experimental groups increased statistically significantly relative to the healthy tissue of intact animals, and the greatest differences from the control were recorded in the group of animals with implanted H1299 culture at a concentration of 1 × 106 . Superoxide dismutase activity in the studied lysates of intracranial xenografts and peritumoral tissues statistically significantly increased compared to the control sample in all experimental groups. The highest increase in the SOD activity was observed in the tissues of intracranial xenografts with the highest tumor load, which amounted to 28.8 % and 32.9 % of the changes relative to the control sample. A statistically significant increase in the concentration of SH-groups relative to the control sample in tumor tissue lysates was revealed in all experimental groups, and the highest concentration (36.2 ± 0.47) was observed in the group of experimental animals with the highest tumor load. Percentage change in tail moment (DNA damage indicator) in groups O1, O2, O3 and O4 increased statistically significantly compared to the control sample by 55.8 %, 111.8 %, 97.3 % and 170 %, respectively.Conclusions. The observed increase in the activity of the antioxidant defense system, accumulation of oxidative modifications of proteins, and an increase in DNA double-strand breaks in the tissues of intracranial xenografts of non-small cell lung cancer in vivo suggest that the created models reflect processes similar to those in tumors of human non-small cell lung cancer.

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.

Purpose of the study. Was was the creation of a Patient Derived Xenograft (PDX) model of non‑small cell lung cancer in immunodeficient mice adapted to growth in immunodeficient mice.Materials and methods. The study was performed using the tumor material from 14 donors implanted subcutaneously to 132 immunodeficient Balb/c Nude mice. Xenografts were maintained until the third passage. PDXs in the third passage from 3 patients were used to assess the model sensitivity to cisplatin. A histological analysis and genetic tests for the presence of EGFR mutations were performed for donor tumors from 3 patients and the corresponding xenografts in the third passage.Results. We observed a noticeable PDX growth already on the 8th day after the tumor material implantation. Successful xenograft engraftment was noted in 21 of 42 mice (50 %), which were rather successful results. A comparative histological analysis of tumor material from 3 patients showed that the PDX models retained the original histotype. We also demonstrated the identity of the EGFR mutations in the established xenografts from 3 patients and the donor tumors, which proved the value of these PDX models for preclinical studies of substances with potential antitumor activity. The analysis of the xenograft sensitivity to cytostatic cisplatin showed a statistically significant decrease in the growth rate in the xenografts obtained from 2 out of 3 patients, in comparison with the control.Conclusions. The created PDX models can be recommended as test systems for preclinical studies of the effectiveness of new pharmacological substances with potential antitumor activity.

Purpose of the study. Was to analyze antitumor efficacy of the XAV 939 Wnt signaling pathway inhibitor and its combination with 5 fluorouracil in subcutaneous xenografts derived from patients with colorectal cancer.Materials and methods. Antitumor efficacy of the agents and their combination was studied in xenografts derived from patients with colorectal cancer and subcutaneously implanted in immunodeficient Balb/c Nude mice. All animals with tumors were divided into 4 groups (n = 5): group 1 received 5 fluorouracil 25 mg/kg, group 2 – XAV 939 25 mg/kg, group 3–5 fluorouracil and XAV 939 combination at the same dosages, group 4 was control. Criteria for the efficacy of the tested agents and their combination included tumor growth rate and tumor growth inhibition rate (TGI %).Results. The mean volumes of xenografts and tumor growth rate in the group receiving a combination of 5 fluorouracil and XAV 939 were 335.2 ± 40.7 mm3 , being lower than the averages of xenografts in controls – 609.3 ± 69.5 mm3 (p < 0.05). The mean volumes of xenografts in the group receiving 5 fluorouracil monotherapy were 601.9 ± 45.5 mm3 , in the group with the XAV 939 monotherapy – 527.9 ± 258.6 mm3 . The highest TGI (44.99 %) was registered in the group receiving a combination of 5 fluorouracil and XAV 939.Conclusion. The study revealed the ability of combined XAV 939 Wnt signaling pathway inhibitor and 5 fluorouracil to inhibit the growth of subcutaneous xenografts derived from patients with colorectal cancer.