Purpose of the study . Assessment of the level of certain cytokines in the saliva of patients with primary locally advanced cancer of the oral mucosa in addition to surgical treatment with intraoperative PDT (IPDT). Patients and methods. Patients with primary locally advanced cancer of the oral mucosa T3-4aN0-2M0 were divided into 2 groups: the main group (30 patients) underwent radical tumor removal supplemented with IPDT and the control group (30 patients) without addition. IPDT was performed using Latus-T (farah) and a chlorin E6 photosensitizer. Cytokine levels were determined in unstimulated whole saliva the day before, on the 3rd and on the 7th day after the operation by the ELISA multiplex analysis method. Results. A similar dynamic of the cytokine profile of patients of both groups was shown: on the 3rd day after surgery, the levels of G-CSF, IL-6, MIP-1β increased, and GM-CSF and IFN-γ decreased compared with baseline values. On the 7th day, the dynamics of G-CSF, GM-CSF, IL-6 persisted, while IL-8, IL-10, IL-12 changed to the opposite. Intergroup differences were revealed in the level of IL-1β - on day 3, an increase in the main group and a decrease in the control group. The level of IL-7 on day 7 decreased sharply in the control group and increased statistically significantly in patients receiving IPDT. The main group showed a 4.8-fold increase in IL-8 on day 3 and its 3.6-fold drop on day 7 with the opposite dynamics in the control group. The TNF-α level increased only in the main group on day 7, and in the control group it decreased by 3 and recovered on day 7. On day 3, the MCP-1 level increased in the main group and decreased in the control group. The level of IL-17 in the main group increased on the 3rd day with a further decrease below the baseline, and in the control group it decreased on the 3rd day, followed by a recovery on the 7th. An increase in IL-5 and IL-13 levels on day 3 was noted only in the control group, however, the level of IL-5 in both study periods in the main group was lower than in the control group. Conclusion. IPDT in patients with primary locally advanced oral cancer causes changes in the cytokine composition of saliva during the first week after surgery, some of which can be associated with an elongation of the relapse-free period in such patients.

Epidemiological data indicate high rates of morbidity and mortality of oral mucosal cancer worldwide. At the same time, even visual accessibility does not allow detecting oral cancer in the early stages. The purpose of the study. Assessment of the involvement of cytokines in the development and progression of oral cancer. Materials and methods. The search for publications was carried out in the databases of the RSCI, PubMed, Scopus 2019-2023 years for the following queries: cancer of the oral mucosa; potentially malignant diseases of the oral cavity; precancerous diseases of the oral cavity, inflammation and cancer, cytokines, saliva cytokines, serum cytokines. Results. It is now recognized that under the influence of inflammation, neoplastic and stromal cells interact and control tumor evolution by producing cytokines. Modern studies demonstrate the important role of cytokines such as TNF-α, IL-8, IL-6, IL-1β in the development and progression of oral cancer. A review of the conducted studies indicates that cytokines released by tumor cells of oral cancer, as well as the tumor microenvironment, contribute to cell proliferation, survival, and migration of tumor cells of this localization, although they activate immune cells, contributing to the modulation of the antitumor immune response. Hyperproduction of cytokines, registered at the local and systemic levels, appears to be a consequence of dysregulation of proliferative processes and at the same time one of the causes of tumor spread. Conclusion. Modern research demonstrates the important role of various cytokines in the development and progression of cancer of the oral mucosa. In this regard, therapeutic approaches that limit their growthstimulating activity should be considered.

Colorectal cancer remains in the leading positions in the structures of morbidity and mortality among both sexes. A large number of studies are aimed to reveal new biomarkers targeted at both early diagnosis and improving the effectiveness of drug therapy. Colorectal carcinoma (CC) is heterogeneous in its morphological, molecular and immunological aspects and is a heterogeneous disease. The existing molecular genetic classifications and biomarkers capable of predicting the effectiveness of therapy aren’t optimal enough. New prognostic markers would make it possible to identify a subgroup of patients with a high risk of tumor recurrence, for whom enhanced monitoring and diagnostic monitoring should be established, as well as the selection of highly effective methods in the treatment of colorectal cancer. It has been established that some immune cells in the tumor microenvironment are able to stimulate the development of disease progression. Cytokines and chemokines in the tumor microenvironment stimulate the development of metastases, and their serum levels reflect the current inflammatory response in the tumor tissue. The identification and analysis of immune markers involved in the processes of metastasis and the mechanisms of progression remains an important task of modern medicine. The purpose of the study was to analyze modern ideas about the importance of the immunological microenvironment in the progression of colorectal cancer. The effect of molecular heterogeneity of the tumor on the development of metastases, as well as on resistance to ongoing antitumor therapy. The review reflects the immunological characteristics of CC, including in the context of molecular biological subtypes. It describes the involvement of cells of the immune system (lymphocytes, macrophages) and their products (cytokines, chemokines) in the progression of colorectal cancer, including in the processes of neoangiogenesis, as well as the relationship of the T- and B-cell composition of the tumor microenvironment on the course of the disease. The review also shows the immunogenomic stratification of CC, which can be used to predict the response to immunotherapy for colorectal cancer.

ДИНАМИКА ЦИТОКИНОВОГО ПРОФИЛЯ КРОВИ БОЛЬНЫХ С МЕТАСТАТИЧЕСКИМ КОЛОРЕКТАЛЬНЫМ РАКОМ ПРИ ПРОВЕДЕНИИ анти-EGFR ТЕРАПИИКит О.И., Владимирова Л.Ю

Background. Among all the new methods and approaches, virotherapy with oncolytic viruses, both in combination with immunotherapy and without it, shows high efficiency in various phases of clinical trials and good tolerance by patients.Aim. To study the sensitivity of some immortalized cancer cell lines to the R-92 strain of human reovirus with cell characteristics at the ultrastructural level.Materials and methods. The study was carried out on cell lines of HeLa, A549, U87MG. Cells were planted in an amount of 15 thousand per well of a 96-well plate and after adhesion, the virus was inoculated by adding a medium containing virus particles in 4 tenfold dilutions (approximately 10 9 –106 particles per ml). Next, the cells were cultured for 24 h, after which the number of living cells in the wells was determined indirectly using the methyl tetrazolium test, which was carried out according to standard methods. To study the ultrastructure of infected cells, cells were seeded into a T25 flask and inoculated with the virus at the maximum concentration. After 24 h of cultivation, the cells were fixed in a 2.5 % glutaraldehyde solution in phosphate buffer for 1 h, after which they were washed three times in phosphate buffer and samples were processed for TEM according to standard methods.Results. Diluting the virus 1000 times led to a decrease in the cytostatic effect in all three cultures to a level practically no different from the control. HeLa turned out to be the most sensitive culture to reovirus. In the experiment, the number of living cells decreased to 60.4 ± 10.2 % compared to the control during incubation with the maximum number of viral particles and to 63.7 ± 16.2 % with a tenfold dilution of the virus. This indicator was significantly lower than in the other two studied cultures under these cultivation conditions (p <0.001).In addition, at the maximum virus concentration, the A549 culture was less sensitive than the U87MG culture (p <0.01). At lower concentrations of viral particles, the average viability of the studied cell lines did not differ significantly from each other. Analysis of electron diffraction patterns showed that the virus successfully replicates in the cytoplasm of the studied cultures, but is not released from the cell, which is apparently due to the short incubation period. TEM also showed cell damage characteristic of apoptosis or necroptosis, uniformly expressed in all studied cultures.Conclusion. Cell lines A549, HeLa and U87MG, according to the results of the methyl tetrazolium test, demonstrate different sensitivity to the human reovirus strain P-92. The TEM picture of cells from infected cultures showed signs of the development of apoptosis or necroptosis.

РОЛЬ ЦИТОКИНОВ И ХЕМОКИНОВ В РАЗВИТИИ КОЛОРЕКТАЛЬНОГО РАКА Кит О.И. 1 , Владимирова Л.Ю. 1 , Сагакянц А.Б. 1 , Тишина А.В. 1 , Златник Е.Ю. 1 , Дженкова Е

The last decade is characterized by significant progress in the treatment of rectal cancer (reduction in the number of relapses to 5–6 % with the use of prolonged radiation therapy) before surgery. The greatest success has been achieved in the treatment of cancer of the lower ampulla of the rectum, when it is possible to develop a complete clinical response of the rectal tumor to chemoradiotherapy. Nevertheless, the requirement issues to improve the results of treatment of cancer of the upper and middle ampullar rectum with an increase in the survival of patients remain. Which makes it relevant to develop new methods, that increase the effectiveness of the treatment of rectal cancer. The method of modified chemoradiotherapy for cancer of the upper ampulla of the rectum was developed in our study. The method is as follows: at the first stage, one day before the start of radiation therapy, the patient undergoes superselective catheterization of the superior rectal artery through the radial or femoral artery, followed by regional administration of radiomodifying chemotherapy drugs: cisplatin 50 mg and fluorouracil 500 mg. In one day, patients begin to undergo a course of conformal remote large- fraction radiation therapy to the primary focus and metastasis pathways for 5 sessions with a single focal dose of 5 Gy to a total focal dose of 25 Gy using a low-energy linear accelerator. During the entire course of radiation therapy, fluorouracil 500 mg is administered daily intravenously for 30 minutes in 30 minutes before the session. Surgical intervention with the sampling of material for research is carried out 6–8 weeks after the radiation therapy is completed. To assess the effectiveness of the modified chemoradiotherapy, the stage of tumor regression was determined according to the RECIST scale, and the level of therapeutic pathomorphology of the tumor according to Dworak was determined during a morphological study of the rectal tumor removed during the operation. The developed method of modified chemoradiotherapy makes it possible to achieve regression of the rectal tumor in a short time, reduce the time and increase the effectiveness of treatment. The method of modified chemoradiotherapy is intended for patients with cancer of the upper and middle ampullar rectum T3-4N0-2M0, for whom radiation therapy is indicated as the first stage of treatment, after which resection of the rectum is performed in a standard volume.

УДК 616.24-006.66 ОСОБЕННОСТИ ПОПУЛЯЦИОННОГО СОСТАВА ИММУНОКОМПЕТЕНТНЫХ КЛЕТОК ПЕРИФЕРИЧЕСКОЙ КРОВИ У ПАЦИЕНТОВ С НЕМЕЛКОКЛЕТОЧНЫМ РАКОМ ЛЕГКОГО НА ФОНЕ ПРОВОДИМОЙ ИММУНОТЕРАПИИ С РАЗЛИЧНОЙ ЕЕ ЭФФЕКТИВНОСТЬЮСагакянц А

Purpose of the study. Was to reveal characteristics of the immunocompetent cells in colon cancer (CC) according to the disease stage, and to identify prognostic factors of cancer development.Materials and methods. The study included 50 patients with CC: stage I – 4 patients (8 %), II – 25 (50 %), III – 21 (42 %). All patients underwent standard surgical intervention at the initial stage, the obtained material was used for subsequent studies: a cell suspension was obtained from the tumor tissue, peritumoral zone (1–3 cm from the tumor), which was treated with an antibody panel (Becton Dickinson, USA) to identify the main subpopulations of leukocytes and lymphocytes.Results. The tumor tissues of patients with stages I + II showed a decrease in the relative number of DP, DN, NKT and CD19+, compared to peritumoral tissues, by 33 %, 42 %, 31 % and 82 % respectively. Tumor tissues of stage III patients demonstrated elevated relative numbers of CD3+, CD4+, NK by 57 %, 34 %, 48 %, and decreased DP, DN, NKT, CD19+ by 33 %, 74 %, 31 %, 59 %, compared to peritumoral tissues. DP, DN, NKT and CD19+ in the tumor decreased by 78 %, 74 %, 39 %, 60 %, respectively, and the relative number of lymphocytes increased by 138 %, compared to the tissues of the resection line. A comparative analysis of local immunological parameters in the tumor tissues of patients with СС revealed that the relative numbers of lymphocytes and CD19+ were 58 % and 87 % higher, and DP and DN were 33 % and 27 % lower in tumor tissues of stage III patients, compared to tumor tissues of stage I + II patients.Conclusion. Thus, the obtained features of the local population and subpopulation composition of immunocompetent cells in CC, depending on the stage of the tumor process, can be used to predict the clinical course of the disease.

КОРРЕКЦИЯ ЛОКАЛЬНОГО ИММУНИТЕТА И СОСТАВА ТКАНЕВЫХ ЦИТОКИНОВ С ПОМОЩЬЮ ПРЕПАРАТА АНТИТЕЛ У БОЛЬНЫХ РАКОМ ОБОДОЧНОЙ КИШКИЗлатник Е.Ю. 1 , Симоненко Н.И. 2 , Дженкова Е.А. 1 , Шульгина О.Г. 1 , Максимов А.Ю. 1 , Маслов А

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.

ПАРАМЕТРЫ СИСТЕМНОГО КЛЕТОЧНОГО ИММУНИТЕТА У ПАЦИЕНТОВ С МЕЛАНОМОЙ КОЖИ НА ФОНЕ ПРОВОДИМОЙ ИММУНОТЕРАПИИ С РАЗЛИЧНОЙ ЕЕ ЭФФЕКТИВНОСТЬЮСагакянц А.Б. 1 , Теплякова

Purpose of the study. Was to reveal the antitumor effect of 2‑(6,8‑dimethyl‑5‑nitro‑4‑chloroquinoline‑2‑yl)‑5,6,7‑trichloro‑1,3‑tropolone in subcutaneous PDX models of human lung cancer.Material and methods. The studied tropolone was synthesized using a method of expanding the o‑quinone cycle. Assess to it’s toxic effects was given by the survival and changes in the health status of female Balb/c Nude mice. Antitumor tropolone effects were studied in subcutaneous patient‑derived xenograft (PDX) models of human squamous cell lung cancer in Balb/c Nude mice. The average volumes of tumor nodes and tumor growth inhibition (TGI %) rate were taken into account. Biochemical blood tests and histological analysis of the tumor material were performed in recipient mice.Results. An analysis of acute tropolone toxic effects did not reveal the lethal dose. The maximal TGI was observed on day 36 of the experiment in group 5 which have received 2.75 mg/g tropolone and accounted 73.5 % for females and 74.4 % for males. The average tumor volumes in females of this group were 431.3 ± 1,1 mm3 on day 33 of the experiment, in males – 428.9 ± 1,7 mm3 on day 30, and then the tumor volumes declined. The biochemical analysis of blood and histological examination of the tumor tissue of recipient mice reflect the severity of the antitumor effect on the dose of the studied tropolone.Conclusion. The research demonstrated the antitumor activity of 2‑(6,8‑dimethyl‑5‑nitro‑4‑chloroquinoline‑2‑yl)‑5,6,7‑trichloro‑1,3‑tropolone against subcutaneous PDX models of human NSCLC. The revealed tendencies can be used to search for effective modes of the compound application in clinical practice.

Purpose of the study . Was to evaluate overall survival of CC patients after D2 and D3 lymph node dissections and assess the frequency of postoperative complications and dynamics of postoperative recovery. Materials and methods . The study included 50 CC patients aged 39–84 years. Results. The comparative assessment of the overall survival, frequency of postoperative complications and dynamics of postoperative recovery was performed in patients divided into 2 groups depending on the lymph node dissection extent. Group 1 included 23 patients (46 %) with D2 lymph node dissection, group 2–27 patients (54 %) with D3 lymph node dissection. 8 (16 %) patients developed complications in the early postoperative period. Patients in group 1 had grade I (5 patients) and grade IIIb (1 patient) surgical complications, according to the Clavien-Dindo classification. 2 patients in group 2 developed grade III b complications. No significant differences were found between groups in peristalsis, gases and bowel movement, starting eating and drinking. A significant increase in the number of postoperative bed-days was observed in patients who underwent open surgery, compared with the group with laparoscopic access. No statistically significant difference was found in the overall survival in patients of the two groups (p = 0.918). Conclusion . The rates of postoperative complications that required repeated surgery were comparable between the groups with D2 and D3 lymph node dissections. D3 lymph node dissection did not affect the dynamics of postoperative recovery and the overall survival of patients.

ВЛИЯНИЕ СТЕРЕОТАКСИЧЕСКОЙ РАДИОХИРУРГИИ НА ЭКСПРЕССИЮ МИКРОРНК В ПЛАЗМЕ КРОВИ ПАЦИЕНТОВ С МЕТАСТАТИЧЕСКИМ ПОРАЖЕНИЕМ ГОЛОВНОГО МОЗГА НЕМЕЛКОКЛЕТОЧНЫМ РАКОМ ЛЕГКОГО Вошедский В.И. 1 , Дженкова Е.А. 1 , Сакун П.Г. 1 , Росторгуев Э.Е. 1 , Розенко Л.Я. 1 , Збраилова Е.С. 1 , Власов С.Г. 1 , Командиров М.А. 1 , Родионова О.Г. 1 , Карнаухова Е

Colorectal cancer (CRC) is a relevant issue of modern oncology and ranks the third place among most common malignancies. Every year, more than 1 million new cases of CRC are diagnosed worldwide, with approximately the same frequency of prevalence among the male and female population. Colon cancer (CC) amounts for more than half of all cases of CRC, and it’s incidence and mortality remain rather high. Surgery remains the main method of CRC treatment, and determining the extent of surgery and lymph node dissection remains an urgent problem. For the first time in Japan, a classification of groups of lymph nodes (l.n.) was proposed depending on the level of lymph outflow and location in relation to the main vessels. According to the numbering of l.n. groups by the Japanese Society for Cancer of the Colon and Rectum (JSCCR), all lymph nodes are numbered with three digits. As a rule, lymphogenic metastasis occurs in one direction, bilateral spread is possible if the tumor is located at the same distance from two feeding vessels. With tumors of the right-sided localization, all groups of l.n. located along the branches of the superior mesenteric artery are removed, and with tumors of the left half of the colon, all l.n. located along the trunk of the inferior mesenteric artery are removed. The presence of affected l.n. is important for assessing the prognosis and further determining the need for adjuvant therapy. Some literature data demonstrate good results of surgical interventions performed in accordance with the concept of embryonic planes and complete mesocolonic excision. D3 lymph node dissection is not performed in daily practice in some European countries and North America, unlike a number of Eastern countries. However, the level of vessel ligation remains the subject of scientific discussion. The purpose of this review was to analyze the available literature on the problem of choosing the level of lymph node dissection in CC surgery.

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. To evaluate the number of cells with the CD45+/- phenotype expressing Toll-like receptors (TLRs) in tissues of the tumor, peritumoral area and resection line tissues in colon cancer (CC) with various tumor locations.Materials and methods. The study included 50 patients with CC. All patients underwent surgery as the primary treatment, and tissue material was collected from the patients. Expression of TLRs (2, 3, 4, 8, 9) on CD45+, CD45- cell populations was determined by flow cytometry in cell suspensions obtained from tissues of the tumor, peritumoral area (1–3 cm from the tumor) and resection line tissues (~10 cm from the tumor) with further calculation of the percentage of cells with the corresponding phenotype from the total number of cells.Results. An analysis of left-sided colon tumors showed lower percentage of CD45- cells expressing TLR4, 8, compared to rightsided tumors, by 38 % and 25 %. A comparative analysis of the number of CD45+ cells expressing TLR 2, 4 showed their decrease by 81 % and 87 %, respectively, compared with right-sided tumors. An assessment of the data in the perifocal zone of left-sided colon tumors, compared with right-sided ones, demonstrated a decrease in the percentage of cells with the CD45- phenotype that express TLR4, by 61 %. Resection line tissues in left-sided tumors, compared with right-sided ones, showed a statistically significant increase in the percentage of CD45- cells that express TLR 2, 4 by 205 % and 55 %, respectively. The number of CD45+ cells expressing TLR 4 decreased by 87 %. An assessment of the number of cells expressing TLRs 3 and 9 in the tumor, peritumoral area and resection line tissues did not reveal significant differences.Conclusions. Lower number of cells with CD45+ and CD45- phenotypes express TLRs 2, 4, 8 in left-sided colon tumors and their peritumoral tissues, compared to right-sided cancer.

Background: Colorectal cancer is now an urgent problem in oncology. Recently, specialists have been interested in a comparative analysis of differences in the clinical course of malignant tumors in the proximal and distal colon. The sections differ not only in their embryogenesis and sources of blood supply, but also in the clinical course and population and epidemiological characteristics. The issue of distinctive immunological characteristics of tumors of the colon depending on the location remains open.Objective: A comparative analysis of local subpopulations of immunocompetent cells and an assessment of number of cells with the CD45+/- phenotype expressing toll-like receptors (TLRs) depending on the tumor location on the right or left sides of the colon.Material and methods: The study included 50 patients with verified colon cancer. The majority of patients were females – 26 (52%), aged 67 ± 0.4 years, and 50% of patients with stage II disease. Depending on the tumor location (the right or left sides of the colon), the patients were divided into 2 groups of 25 people each. All patients underwent standard surgery at the initial stage. The obtained material was used for subsequent studies: a cell suspension was obtained from a tumor tissue fragment, the perifocal zone (1–3 cm from the tumor) which was processed using an antibody panel (Becton Dickinson, USA) to identify the main subpopulations of leukocytes and lymphocytes. Expression of TLRs (2, 3, 4, 8, 9) on CD45+, CD45- cell populations was also determined using the BD FACSCanto flow cytometer (Becton Dickinson, USA). Statistical processing of the results was performed using the STATISTICA 13.3 package (StatSoft Inc., USA).Results: A comparative analysis of immunological parameters, depending on the tumor location on the right or left sides of the colon, showed:Tissues of the right-sided tumors had a higher T-lymphocytic infiltration, compared to the left-sided tumors, while the latter showed a higher B-lymphocytic infiltration (p = 0.025).Peritumoral zone tissues of left-sided tumors demonstrated a decrease of lymphocytes levels (p = 0.027), NKT – (p = 0.035), NK – (p = 0.041) and В lymphocytes (p = 0.038), and a significant increase in CD8+- (p = 0.02) and DP cells (p = 0.0018).Left-sided tumors showed a percentage decrease of CD45- cells expressing TLR4 and TLR8, compared to right-sided tumors, by 38% (p = 0.038) and 25% (p = 0.043).There was a decrease in the number of CD45+ cells expressing TLR2 and TLR4 in left-sided tumors by 54% (p = 0.035) and 33% (p = 0.04) respectively, than in right-sided tumors.The percent of CD45- cells expressing TLR4 in the perifocal tissues of left-sided tumors decreased by 61% (p = 0.031) in comparison to the corresponding tissues in right-sided tumors.The numbers of CD45+ cells expressing TLR2 and TLR4 were 81% (p = 0.02) and 87% (p = 0.018) lower respectively in the peritumoral tissues of left-sided tumors, compared to the corresponding tissues in right-sided tumors.Conclusion: The revealed characteristics of the local subpopulations of immunocompetent cells and the numbers of CD45+/- cells expressing TLRs depending on the tumor location on the right or left sides of the colon can serve as a prognosis of the disease clinical course and the choice of further treatment tactics.