Daria Artemova

Lung cancer is the most common type of cancer worldwide. Tumors carrying a mutation in the STK11 gene are associated with severe prognosis and resistance to therapy. New treatments for pulmonary adenocarcinoma highlight the efficacy of High-LET neutron therapy, often combined with drug therapy. PCSK9, whose inhibitors are used to treat dyslipidemia, may also be a new target in lung cancer therapy. CRISPR-Cas9-mediated STK11 mutation was performed in murine LLC1 lung adenocarcinoma cells. Human A549 cells that naturally carry a homozygous loss-of-function mutation in the STK11 gene were also used. Cells were irradiated with protons, neutrons, and photons (2 Gy) and analyzed for survival, apoptosis, clonogenic survival assay, and evolocumab (PCSK9 inhibitor) sensitivity. In vivo xenograft (Nude) and syngeneic (C57BL/6) subcutaneous tumor models were neutron-irradiated (5 Gy). Tumor cell proliferation, microenvironment, and protein expression were assessed. High-LET irradiation confirmed the STK11-deficient lines radio resistance, which did not reduce under PCSK9 inhibitor treatment conditions in vitro. In animal models, the PCSK9 inhibitor decreased Ki67 index of tumor cells and infiltration of cancer-associated fibroblasts and macrophages in the combination therapy group. Particle therapy resistance serves as a crucial prognostic marker in the management of lung adenocarcinoma. Using cell lines and animal models, we successfully described this resistance phenotype and demonstrated the promising use of a PCSK9 inhibitor to enhance the efficacy of hadron radiotherapy against lung cancer.

The spleen is one of the key organs of the immune system that is involved in both innate and adaptive immunity. Splenectomy (SE) is surgery with many risks, including sepsis, thrombosis, and malignancy. In this regard, studies into the potential regeneration of the spleen and restoring its structure and functions are important. As in the past, heterotopic spleen transplantation regenerates the spleen structure after 30 days. This study assessed the impact of heterotopic spleen regeneration on tumor growth. We used two animal models. In the first, animals had SE. In the second, animals had SE and subcutaneous transplantation (ST) of spleen fragments. These animals, as well as intact animals, were transplanted under the skin with tumor cells to obtain a subcutaneous model of tumor growth. The results showed that while there was no significant effect on tumor growth at 15 days, there was a decrease in tumor cell proliferation rate. Spleen regeneration stimulated early occupancy of the tumor niche by macrophages, as well as influx of CD4+ T‐lymphocytes and B‐lymphocytes into the tumor, while infiltration of CD8+ T‐lymphocytes was suppressed. Thus, the effects of regenerating spleen on tumor growth that we have demonstrated require further investigation at longer follow‐up periods.

Relevance. Despite longstanding recognition of endometriosis, there’s an absence of effective treatment. Existing treatments carry significant risk, so research into cell therapy is gaining popularity. Macrophages are a promising agent. A previous study using an animal model demonstrated that introducing proinflammatory macrophages led to a significant reduction in endometriosis lesions. The aim of the study is to analyze the effect of macrophages with a proinflammatory phenotype introduced into an animal model on the proliferation and survival of cells in endometriosis lesions. Materials and Methods. A syngeneic model of endometriosis was obtained in female C57Bl/6 mice by intraperitoneal transplantation of uterine fragments from a donor mouse. RAW264.7 mouse macrophages were utilized as the cellular agent. The animals were then divided into groups: “Control” comprised mice that did not receive macrophage therapy; “Control of therapy” comprised mice that received unpolarized RAW264.7 macrophages; and “Therapy” comprised mice with endometriosis that were injected with RAW264.7 macrophages with a proinflammatory phenotype. Results and Discussion. Consequently, the administration of macrophages with a proinflammatory phenotype resulted in a significant decrease in the production of the proliferation marker protein Ki-67 and a significant increase in the production of effector caspase 3 in the cells of endometriosis lesions compared to the “Control” group. Concurrently, the level of production of the tumor suppressor protein p53, which is involved in the initiation of apoptosis in cells, was comparable to that in the“Control” group. This is in contrast to the group of animals that received unpolarized macrophages. Conclusion. We found that the anti-endometriosis activity of macrophages with a proinflammatory phenotype is associated with the fact that their introduction suppressed the proliferation of endometriosis cells and enhanced their apoptotic death through the activation of p53 and caspase 3.

BACKGROUND: On-treatment drug resistance is a major concern in brain tumor therapy, significantly reducing the efficacy of conventional chemotherapy. Three-dimensional (3D) cell models are a powerful tool in experimental oncology for assessing drug resistance mechanisms in tumor cells, including the role of extracellular matrix-activated signaling pathways. AIM: The work aimed to assess the effect of hyaluronic acid on doxorubicin resistance in 3D in vitro models of brain tumors. METHODS: 2D monolayer cultures were obtained from continuous cell lines of brain tumors in laboratory animals. The cell lines were derived from the unique collection of the A.P. Avtsyn Research Institute of Human Morphology of the B.V. Petrovsky Russian Research Center of Surgery. 3D spheroids were formed using ultra-low attachment plates with or without hyaluronic acid. The cytotoxicity of doxorubicin was assessed using the ССК-8 kit. Fluorimetry was used to measure doxorubicin efflux efficiency and CD44 production, whereas flow cytometry was used to assess the fraction of CD44+ cells. The expression of genes responsible for drug resistance was assessed using real-time polymerase chain reaction. RESULTS: The IC50 of doxorubicin in 2D models was as follows: 180 nM for oligodendroglioma 51/7, 280 nM for glioblastoma 14-60-4, 500 nM for astrocytoma 10-17-2, and 2750 nM for neurinoma RGGN2. The IC50 of doxorubicin determined for 2D models had no significant effect on the viability of cells in spheroids. However, a fourfold increase in its concentration induced a cytotoxic effect, the severity of which was determined by spheroid compaction. Hyaluronic acid increased doxorubicin resistance in 3D models of brain tumors in a dose-dependent manner. This effect was associated with CD44 receptor activation and enhanced drug efflux from cells, which were mediated by changes in the expression of ABC transporter genes (Abcb1, Abcg2, Abcc1) and DNA repair genes (Mgmt, Top2a). CONCLUSION: The findings clarify the role of hyaluronic acid and the CD44 receptor in drug resistance in brain tumors, facilitating the development of more relevant in vitro models. Furthermore, the findings have practical significance for developing drug resistance-overcoming strategies, such as targeted inhibition of ABC transporters or suppressed interactions between hyaluronic acid and its CD44 receptor.

In mammals, the liver and spleen are closely related to each other and form the so-called liver-spleen axis. The functioning of this axis is based on anatomical connection through portal circulation, as well as the commonality of many functions performed. The connection between the liver and spleen is most pronounced in the development of such pathologic conditions as fibrosis and cirrhosis. Some clinical and experimental studies found that removal of the spleen leads to a decrease in the severity of liver fibrosis. A positive effect of spleen removal has also been found in liver resection and liver transplantation. Different authors suggest several mechanisms of this effect. It is assumed that the spleen in the development of fibrosis becomes an additional source of cytokines damaging the liver. In addition, monocytes and other leukocytes that support inflammation may migrate from the spleen to the liver. Another mechanism may be a decrease in blood pressure levels in the hepatic portal vein after splenectomy. Despite the available evidence, the mechanisms of this effect remain poorly understood. This issue is relevant for biomedical research, as it may form the basis for the development of new ways to treat liver diseases and stimulate its regeneration.

Glioblastoma (GBM) is a highly aggressive human neoplasm with poor prognosis due to its malignancy and therapy resistance. To evaluate the efficacy of antitumor therapy, cell models are used most widely, but they are not as relevant to human GBMs as tissue models of gliomas, closely corresponding to human GBMs in cell heterogeneity. In this work, we compared three different tissue strains of rat GBM 101.8 (induced by DMBA), GBM 11-9-2, and GBM 14-4-5 (induced by ENU). Materials and methods: We estimated different gene expressions by qPCR-RT and conducted Western blotting and histological and morphometric analysis of three different tissue strains of rat GBM. Results: GBM 101.8 was characterized by the shortest period of tumor growth and the greatest number of necroses and mitoses; overexpression of Abcb1, Sox2, Cdkn2a, Cyclin D, and Trp53; and downregulated expression of Vegfa, Pdgfra, and Pten; as well as a high level of HIF-1α protein content. GBM 11-9-2 and GBM 14-4-5 were relevant to low-grade gliomas and characterized by downregulated Mgmt expression; furthermore, a low content of CD133 protein was found in GBM 11-9-2. Conclusions: GBM 101.8 is a reliable model for further investigation due to its similarity to high-grade human GBMs, while GBM 11-9-2 and GBM 14-4-5 correspond to Grade 2–3 gliomas.

Endometriosis is a chronic inflammatory estrogen-dependent disease characterized by the growth of endometrial-like tissue outside the physiological region. Despite the fact that this disease is common, laparoscopic surgery is currently the gold standard in the treatment of endometriosis. In this regard, it is necessary to develop new effective methods of minimally invasive therapy for endometriosis. One of the promising areas in the treatment of endometriosis is cell therapy. Cellular therapy is a vast branch of therapeutic methods with various agents. Potential cell therapies for endometriosis may be based on the principle of targeting aspects of the pathogenesis of the disease: suppression of estrogen receptor activity, angiogenesis, fibrosis, and a decrease in the content of stem cells in endometriosis foci. In addition, immune cells such as NK cells and macrophages may be promising agents for cell therapy of endometriosis. Standing apart in the methods of cell therapy is the replacement therapy of endometriosis. Thus, many studies in the field of the pathogenesis of endometriosis can shed light not only on the causes of the disease and may contribute to the development of new methods for personalized cell therapy of endometriosis.

Background: Macrophages play a key role in liver regeneration. The fates of resident macrophages after 70% resection are poorly investigated. In this work, using the MARCO macrophage marker (abbreviated from macrophage receptor with collagenous structure), we studied the dynamics of mouse liver resident macrophages after 70% resection. Methods: In BALB/c male mice, a model of liver regeneration after 70% resection was reproduced. The dynamics of markers CD68, TIM4, and MARCO were studied immunohistochemically and by using a Western blot. Results: The number of MARCO- and CD68-positive macrophages in the regenerating liver increased 1 day and 3 days after resection, respectively. At the same time, the content of the MARCO protein increased in the sorted macrophages of the regenerating liver on the third day. Conclusions: The data indicate that the number of MARCO-positive macrophages in the regenerating liver increases due to the activation of MARCO synthesis in the liver macrophages. The increased expression of MARCO by macrophages can be regarded as a sign of their activation. In the present study, stimulation with LPS led to an increase in the expression of the Marco gene in both Kupffer cells and macrophages of bone marrow origin.

Endometriosis and cancer have much in common, notably their burgeoning of cells in hypoxic milieus, their invasiveness, and their capacity to trigger remodeling, vascularization, and innervation of other tissues. An important role in these processes is played by permissive microenvironments inhabited by a variety of stromal and immune cells, including macrophages. Remarkable phenotypical plasticity of macrophages makes them a promising therapeutic target; some key issues are the range of macrophage phenotypes characteristic of a particular pathology and the possible manners of its modulation. In both endometriosis and cancer, macrophages guard the lesions from immune surveillance while promoting pathological cell growth, invasion, and metastasis. This review article focuses on a comparative analysis of macrophage behaviors in endometriosis and cancer. We also highlight recent reports on the experimental modulation of macrophage phenotypes in preclinical models of endometriosis and cancer.