RU2757676C1 - Method for stimulating hematogenous dissemination of carcinoma in experiment - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to medicine, namely to experimental oncology, and can be used to stimulate the oncological process by modifying the carcinogenesis of diabetes mellitus. The method for stimulating hematogenous dissemination of carcinoma in the experiment is that in female nonlinear rats at the age of 3.5-4 months diabetes mellitus (DM) is induced by a single intraperitoneal injection of alloxan at a dose of 150 mg/kg of body weight. After 1 week, against the background of a consistently high level of glucose in the blood, the rats are inoculated with Guerin's carcinoma by injecting tumor suspension under the skin of the right scapula in a volume of 0.5 ml and diluting in physiological solution 1:5.

EFFECT: invention can serve as a model for studying the role of diabetes mellitus in the pathogenesis of malignant growth, as well as for finding ways of drug treatment of this pathology; the method is economical and affordable.

1 cl, 4 dwg, 1 tbl

Description

The invention relates to medicine, namely to experimental oncology, and can be used to stimulate the oncological process by modifying the carcinogenesis of diabetes mellitus.

Diabetes mellitus (DM) and cancer are serious and widespread pathologies (see Wang M., Yang Y., Liao Z. Diabetes and cancer: Epidemiological and biological links. World journal of diabetes. 2020; 11 (6): 227 –238. DOI: 10.4239 / wjd.v11.i6.227). Diabetes mellitus is a group of endocrine diseases associated with impaired glucose metabolism in the body and, as a result, its accumulation.

Globally, the number of people with diabetes in 2014 was 422 million, while in 2035 the number of cases is predicted to increase to at least 592 million (see Khan RM, Chua ZJ, Tan JC, Yang Y., Liao Z., Zhao Y . From Pre-Diabetes to Diabetes: Diagnosis, Treatments and Translational Research. Medicina (Kaunas) 2019: 55). Meanwhile, most medical researchers also view cancer as a metabolic disease. The WHO estimates that the number of cancer patients in the world will increase from 14 million in 2012 to 22 million in 2032 (see Shi Y., Hu F.B. The global implications of diabetes and cancer. Lancet. 2014; 383: 1947-1948).

Diabetes mellitus is of two types: Type 1 (DM 1) - juvenile or insulin-dependent diabetes mellitus (IDDM), characterized by the inability of the pancreas to produce insulin due to the destruction of beta cells, is common at a young age; Type 2 (T2DM) is mature diabetes (non-IDDM) and occurs due to the inability of cells / tissues to properly respond to the action of insulin.

There is growing evidence that abnormal glucose homeostasis not only affects the prognosis of cancer, but is also an independent risk factor for the development of certain neoplasms: cancer of the liver, biliary tract, pancreas, stomach, colon, kidney, bladder, breast, and endometrium. (see Friberg E, Orsini N, Mantzoros CS, Wolk A. Diabetes mellitus and risk of endometrial cancer: A meta-analysis. Diabetologia. 2007; 50: 1365-1374; see Vigneri P., Frasca F., Sciacca L ., Pandini G., Vigneri R. Diabetes and cancer Endocr Relat Cancer 2009; 16: 1103-1123; see Lam EK, Batty GD, Huxley RR, Martiniuk AL, Barzi F, Lam TH, et al. Associations of diabetes mellitus with site-specific cancer mortality in the Asia-Pacific region Ann Oncol 2011; 22: 730-738; see Ben Q., Xu M., Ning X., Wang Y., Li Y. Diabetes mellitus and risk of pancreatic cancer: A meta-analysis of cohort studies. Eur J Cancer. 2011; 47: 1928-1937; see Ge Z., Ben Q., Qian J., Wang Y., L. i Y. Diabetes mellitus and risk of gastric cancer: A systematic review and meta-analysis of observational studies. Eur J Gastroenterol Hepatol. 2011; 23: 1127-1135; see Ren H.B., Yu T., Liu C., Li Y.Q. Diabetes mellitus and increased risk of biliary tract cancer: Systematic review and meta-analysis. Cancer Causes Control. 2011; 22: 837-847; see Jiang Y, Ben Q, Shen H, Lu W, Zhang Y, Zhu J. Diabetes mellitus and incidence and mortality of colorectal cancer: A systematic review and meta-analysis of cohort studies. Eur J Epidemiol. 2011; 26: 863-876; see Wang C., Wang X., Gong G., Ben Q., Qiu W., Chen Y. Increased risk of hepatocellular carcinoma in patients with diabetes mellitus: A systematic review and meta-analysis of cohort studies. Int J Cancer. 2012; 130: 1639-1648; see Pearson-Stuttard J., Zhou B., Kontis V., Bentham J., Gunter M.J., Ezzati M. Worldwide burden of cancer attributable to diabetes and high body-mass index: A comparative risk assessment. Lancet Diabetes Endocrinol. 2018; 6: 95-104).

There is strong evidence for a link between cancer and diabetes. So, Zhou X.H. et al. (see Zhou XH, Qiao Q., Zethelius B., Pyörälä K., Söderberg S., Pajak A. Diabetes, prediabetes and cancer mortality. Diabetologia. 2010; 53: 1867-1876) studied 17 different populations and found that the mortality rate from cancer in them was: in people in a state of prediabetes - 1.12, in people with newly diagnosed diabetes - 1.28, in patients with a known diagnosis of diabetes - 1.57. Qi et al. in 2019 investigated the risk of 23 common types of cancer among patients with type 2 diabetes (T2DM) in a large sample (8485 people).

The standard cancer incidence rates for men and women were 1.34 and 1.62, respectively. Men with type 2 diabetes were found to have an increased risk of developing cancer of the prostate, blood, skin, thyroid gland, kidneys, liver, pancreas, lungs, colon, and stomach, and women with type 2 diabetes had an increased risk of cancer of the nasopharynx and liver. , esophagus, thyroid, lungs, pancreas, lymphomas / leukemias, uterus, colon, breast, cervix and stomach.

Diabetes mellitus is considered a risk factor for cancer of all sites in both women and men, while the excess risk of cancer in women is slightly higher than in men (see Ohkuma T., Peters SA, Woodward M. Sex differences in the association between diabetes and cancer: A systematic review and meta-analysis of 121 cohorts including 20 million individuals and one million events.Diabetologia. 2018; 61: 2140-2154).

Thus, epidemiological studies provide evidence that diabetes and prediabetes are associated with an increased risk of cancer. Suggestions are made about the possible mechanisms underlying this relationship. Many factors are thought to be responsible for the cause / link between diabetes and cancer.

However, conditions such as hyperinsulinemia, hyperglycemia, and inflammation are considered to be of primary importance for the development of cancer with the progression of diabetes; sex hormones can also play an important role in the progression of the malignant process against the background of diabetes (see Friberg E, Orsini N, Mantzoros CS, Wolk A. Diabetes mellitus and risk of endometrial cancer: A meta-analysis. Diabetologia. 2007; 50: 1365– 1374; see Buysschaert M., Sadikot S. Diabetes and cancer: a 2013 synopsis. Diabetes Metab Syndr. 2013; 7: 247-250; see Phua WW, Wong MX, Liao Z., Tan NS An aPPARent Functional Consequence in Skeletal Muscle Physiology via Peroxisome Proliferator-Activated Receptors Int J Mol Sci 2018: 19).

A Korean study reported an increase in cancer mortality in prediabetic patients with fasting blood glucose levels of 6.1-6.9 mmol / L (see Jee SH, Ohrr H., Sull JW, Yun JE, Ji M., Samet JM Fasting serum glucose level and cancer risk in Korean men and women. JAMA. 2005; 293: 194–202). It is assumed that hyperinsulinemia, directly or through insulin-like growth factor 1 (IGF1), is involved in carcinogenesis, contributing to the onset and progression of cancer.

IGF1 has potent mitogenic and antiapoptotic activity and plays a key role in triggering cancer (see Hu FB, Manson JE, Liu S., Hunter D., Colditz GA, Michels KB Prospective study of adult onset diabetes mellitus (type 2) and risk of colorectal cancer in women. J Natl Cancer Inst. 1999; 91: 542-547). Hyperinsulinemia occurs when the β cells of the pancreas begin to secrete more insulin to compensate for high glucose levels in the body (see Godsland IF Insulin resistance and hyperinsulinaemia in the development and progression of cancer. Clin Sci (Lond). 2009; 118: 315 –332).

In addition, hyperinsulinemia stimulates liver cells to synthesize IGF1. When insulin binds to the insulin receptor on the surface of target cells, IGF1 binds to its receptor (IGF-1R) to activate several metabolic and mitogenic signaling pathways that regulate the metabolism, proliferation, differentiation, migration, and apoptosis of cancer cells (see Poloz Y., Stambolic V. Obesity and cancer, a case for insulin signaling. Cell Death Dis. 2015; 6: e2037; see Liao Z., Tan ZW, Zhu P., Tan NS Cancer-associated fibroblasts in tumor microenvironment - Accomplices in tumor malignancy Cell Immunol. 2019; 343: 103729; see Dong R., Tan Y., Fan A., Liao Z., Liu H., Wei P. Molecular Dynamics of the Recruitment of Immunoreceptor Signaling Module DAP12 Homodimer to Lipid Raft Boundary Regulated by PIP2. J Phys Chem B. 2020; 124: 504-510). Consequently, patients with diabetes develop higher IGF1 levels, which makes them more susceptible to an increased risk of developing many types of cancer (see Price AJ, Allen NE, Appleby PN, Crowe FL, Travis RC, Tipper SJ, Overvad K., Grønbæk H., Tjønneland A., Johnsen NF, Rinaldi S., Kaaks R., Lukanova A., Boeing H., Aleksandrova K., Trichopoulou A., Trichopoulos D., Andarakis G., Palli D., Krogh V. Insulin -like growth factor-I concentration and risk of prostate cancer: results from the European Prospective Investigation into Cancer and Nutrition. Cancer Epidemiol Collins KK The diabetes-cancer link. Diabetes Spectr. 2014; 27: 276-280).

To investigate the effect of elevated insulin levels on HER2-mediated primary tumor growth and lung metastasis, a mouse model of HER2-mediated breast cancer developing in the presence of hyperinsulinemia was used. It was found that, against the background of initial hyperinsulinemia, insulin and IGF1 receptors had higher levels of phosphorylation, while the mass of breast tumors increased, indicating the stimulation of tumor growth through the insulin / IGF axis (see Ferguson RD, Gallagher EJ, Cohen D. , Tobin-Hess A., Alikhani N., Novosyadlyy R., Haddad N., Yakar S., LeRoith D. Hyperinsulinemia promotes metastasis to the lung in a mouse model of Her2-mediated breast cancer.Endocr Relat Cancer. 2013; 20 : 391-401).

Another epidemiological study assessed the correlation between hyperinsulinemia and increased cancer mortality in people with and without obesity. The study included 3060 obese participants (2303 with hyperinsulinemia) and 6718 non-obese participants 2057 with hyperinsulinemia). Overall cancer mortality was markedly higher in patients with hyperinsulinemia than without it (see Tsujimoto T., Kajio H., Sugiyama T. Association between hyperinsulinemia and increased risk of cancer death in nonobese and obese people: A population-based observational study . Int J Cancer. 2017; 141: 102-111).

Recently, more and more studies show that high blood glucose and insulin levels are associated with low circulating sex-binding globulin (DES) levels, which affects the maintenance of glucose homeostasis (see Le TN, Nestler JE, Strauss JF, Wickham EP Sex hormone-binding globulin and type 2 diabetes mellitus. Trends Endocrinol Metab. 2012; 23: 32-40).

Thus, the correlation between DES and the risk of developing diabetes mellitus was studied in 718 postmenopausal women (359 with newly diagnosed type 2 diabetes and 359 healthy women). It has been found that low levels of circulating DES is closely associated with the risk of diabetes. Moreover, the same result was obtained in an independent cohort study of 340 men - 170 with newly diagnosed type 2 diabetes and 170 controls (see Ding EL, Song Y., Manson JE, Hunter DJ, Lee CC, Rifai N., Buring JE, Gaziano JM, Liu S. Sex hormone-binding globulin and risk of type 2 diabetes in women and men. N Engl J Med. 2009; 361: 1152-1163).

Consequently, with an increase in glucose and insulin levels in the blood, the synthesis of DES decreases, which contributes to the synthesis of free estradiol and testosterone. High levels of free forms of sex hormones are associated with a higher risk of developing many types of cancer, such as breast, endometrial and prostate cancers (see Felix AS, Yang HP, Bell DW, Sherman ME Epidemiology of Endometrial Carcinoma: Etiologic Importance of Hormonal and Metabolic Influences. Adv Exp Med Biol. 2017; 943: 3-46). Studies have shown that both bioavailable estradiol and testosterone are elevated in women with diabetes (see Muka T., Nano J., Jaspers L., Meun C., Bramer WM, Hofman A., Dehghan A., Kavousi M. , Laven JS, Franco OH Associations of Steroid Sex Hormones and Sex Hormone-Binding Globulin With the Risk of Type 2 Diabetes in Women: A Population-Based Cohort Study and Meta-analysis. Diabetes. 2017; 66: 577-586), then how the total testosterone concentration in men with diabetes is lower than in men without diabetes (see Ding EL, Song Y., Malik VS, Liu S. Sex differences of endogenous sex hormones and risk of type 2 diabetes: a systematic review and meta- analysis. JAMA 2006; 295: 1288-1299).

Although the mechanism remains unclear, it is likely due to different affinities for DES (see Liu S., Sun Q. Sex differences, endogenous sex-hormone hormones, sex-hormone binding globulin, and exogenous disruptors in diabetes and related metabolic outcomes. J Diabetes. 2018; 10: 428–441; see Gambineri A., Pelusi C. Sex hormones, obesity and type 2 diabetes: is there a link? Endocr Connect. 2019; 8: R1 – R9). This is the main reason why diabetes may play an important role in protecting patients from prostate cancer.

The link between diabetes mellitus and oxidative stress is another issue that requires careful study. Increased oxidative damage in diabetes is thought to be responsible for DNA damage, mutational changes in oncogenes, and ultimately cancer (see Lee SC, Chan JC Evidence for DNA damage as a biological link between diabetes and cancer. Chin Med J (Engl) 2015; 128: 1543-1548).

The incidence of diabetes and cancer worldwide is increasing rapidly due to changes in lifestyle and an increase in life expectancy. Diabetes and cancer are global issues and international health experts or organizations should develop recommendations for the prevention, diagnosis and treatment of diabetes and cancer in order to reduce the social burden.

Since the internal heterogeneity of these two pathologies makes it difficult to conduct research and many questions remain unanswered: Do T1DM and T2DM affect cancer in the same way? In addition, how can one understand the main biological mechanisms of cancer development in the presence of diabetes? Experimental research is needed to answer these questions.

Guerin's carcinoma was isolated from the uterus of an outbred white rat in 1934 by P. Guerin and M. Guerin. Currently, histological structure is poorly differentiated cancer, rarely forming glandular structures. The tumor grafting rate ranges from 50% to 90%, averaging, according to EE Pogosyants, 75%. Spontaneous resorption is not observed. The average lifespan of rats is 30-40 days (see Larionov LF Chemotherapy of malignant tumors. M .: Medgiz, 1962). In the subcutaneous tissue, the tumor grows in the form of soft nodes bounded by a very thin connective tissue capsule. A characteristic feature of Guerin's carcinoma is the arrangement of cells in the form of small cells and short cords, separated by thin but well-defined layers of connective tissue. The formation of true ferruginous structures is not observed; in some areas, pseudo-ferruginous structures are found. Many pathological mitoses are recorded. Along with extensive fields of necrosis, numerous areas of necrobiosis are observed (pycnosis of nuclei, karyorrhexis, karyolysis, etc.). Guerin's carcinoma in its biological properties and morphology largely retained its epithelial character than such transplantable tumors of epithelial origin as the tumor of Ehrlich, Brown-Pierce, etc. . M .: Medgiz, 1960).

One of the factors that alter the development of a malignant tumor is chronic neurogenic pain. It has been established that the reproduction of chronic neurogenic pain in male white outbred rats creates conditions for inoculation of M1 sarcoma in the lung, which is impossible when tumor cells are injected into the subclavian vein in intact animals (see Patent for invention RU 2676 641 C1, publ. 09.01. , Bulletin No. 1). Chronic neurogenic pain modifies the growth of transplantable melanoma B16 / F10 in C57BL / 6 mice (see Patent for invention RU 2 650 587 C1, publ. 04.16.2018, bull. No. 2), and also cancels genetically determined inhibition of malignant growth in mice of the C57BL / 6-PlautmI.IBug-ThisPlau6FDhu / GFDhu strain (see Patent for invention RU 2 718 671 C1, publ. 13.04.2020, bull. No. 1).

Diabetes mellitus is a modifying agent of a different type than chronic pain, directly affecting the endocrine regulation of the body and is increasingly being identified as a pathology accompanying the oncological process. For a number of cancers, diabetes is considered a risk factor.

Known work "Morphological changes in the liver in rats with transplanted liver cancer and alloxan diabetes with intravenous administration of gold nanorods" authors Dikht N.I., Bucharovskaya A.V., Maslyakova G.N., Terentyuk G.S., Pakhomiy S. WITH. et al. (see https://science-education.ru/ru/article/view?id=27728) in which morphological changes in the liver were assessed by intravenous administration of gold nanorods in laboratory animals with transplanted liver cancer against the background of alloxan diabetes. However, the aim of this work was not to study the effect of DM on tumor growth in the liver, but to obtain data on the absence of the damaging effect of gold nanorods, which made it possible to recommend them for use in experimental oncology and diabetology.

The technical result of the present invention is the development of a method for stimulating hematogenous dissemination of carcinoma by modifying carcinogenesis by diabetes mellitus

The technical result is achieved by the fact that in female nonlinear rats at the age of 3.5-4 months, diabetes mellitus is induced by a single intraperitoneal injection of alloxan at a dose of 150 mg / kg of body weight; introduction of tumor suspension under the skin of the right scapula in a volume of 0.5 ml and dilution in physiological solution 1: 5.

Here are the pictures for a better understanding of the method.

Figure 1. Generalization of the malignant process of Guerin's carcinoma. Metastatic lesion of the parietal and visceral peritoneum.

Figure 2. Ovarian tissue preparation. A. - blood supply with the release of tumor cells (× 100); B. - germination of strands of tumor cells (× 100); V. - follicle-like growth of tumor cells of Guerin's carcinoma (× 100); G. - total tumor lesion of the ovaries (× 40). Env. hematoxylin-eosin.

Figure 3. Kidney tissue preparation. A., V. - blood filling and hemorrhage in the parenchyma with the release of tumor cells (× 100); B. - germination of strands of tumor cells; V. and G. - completely destroyed renal structures due to total tumor growth of Guerin's carcinoma (× 40). Env. hematoxylin-eosin.

Figure 4. Preparation of peritoneal tissue. A. - blood filling of the peritoneum (× 100); B. - areas of hemorrhage (× 100); C. - germination of tumor cells into the peritoneal tissue (× 100); G. - total tumor lesion of the peritoneum (× 40). Env. hematoxylin-eosin.

The invention "A method for stimulating hematogenous dissemination of carcinoma in experiment" is new, since it is unknown in the field of experimental research in oncology.

The novelty of the invention lies in the fact that Guerin's carcinoma transplanted against the background of diabetes mellitus in female rats develops more aggressively than in animals of the corresponding sex without diabetes, causing metastatic damage to the walls of the abdominal cavity and internal organs.

The invention "A method for stimulating hematogenous dissemination of carcinoma in an experiment" is industrially applicable, since it can be used in research institutions of an oncological profile to reproduce an experimental model of the progression of carcinoma against the background of diabetes mellitus.

"Method for stimulating hematogenous dissemination of carcinoma in experiment" is performed as follows:

All manipulations with animals are carried out in the box. Tools, dishes, hands are disinfected in the usual way. Female white non-linear rats weighing 180-220 g are injected intraperitoneally with alloxan at a dose of 150 mg / kg body weight. Then, within a week, their blood glucose is measured. A high serum glucose content, in the range of 15-30 nMol / L, indicates the development of diabetes mellitus. One week after the administration of alloxan, against the background of persistent hyperglycemia, rats are subcutaneously inoculated with 0.5 ml of a suspension of Guerin's tumor cells in saline at a dilution of 1: 5. To do this, observing all aseptic conditions, the assistant fixes the rat with its back up, having previously shaved off the hair and treated the skin with a 5% alcohol solution of iodine downward from the corner of the right scapula. The experimenter with a sterile gloved hand grasps the treated skin fold, pierces the skin with a syringe needle, advances the needle subcutaneously and injects a tumor suspension. Then he removes the needle and presses the injection site tightly with a cotton swab dipped in 70% alcohol with a small addition of iodine for 1 minute in order to exclude the outflow of the injected suspension.

3 days after inoculation, subcutaneous tumor growth begins to be visualized at the injection site of a suspension of Guerin's carcinoma cells.

Sexually mature female rats with subcutaneously inoculated Guerin's carcinoma in the same dose and volume as in animals of the main group, but without preliminary reproduction of the model of alloxan diabetes, served as control.

At the time of inoculation of Guerin's carcinoma in females of the main group (n = 8), the average blood glucose was 25.4 ± 1.2 mM / L, while in the control group (n = 8) - 5.2 ± 0.3 mM / l.

In the main group of rats, a subcutaneous tumor began to be detected within 3 days from the moment of inoculation of tumor cells, after 5 days - a subcutaneous tumor node was visualized in all animals.

After 1 week of tumor growth, the average volume of the subcutaneous node of Guerin's carcinoma was 1.1 cm ³ , after 10 days the size of the tumor increased 13.7 times, after 14 days - another 2.5 times (see Table 1).

In 50% of animals with the development of a tumor process against the background of diabetes on the 10th day of the experiment, ascites appeared. With the development of the tumor node from 10 to 14 days, necrosis formed over the tumor.

The first animal from the main group died 11 days after inoculation.

The average lifespan of rats with tumor growth of Guerin's carcinoma against the background of diabetes mellitus was 15.8 days, the maximum - 18 days (see Table 1).

Table 1

Influence of diabetes mellitus on subcutaneous growth of Guerin's carcinoma in sexually mature female rats

Criteria Alloxan Diabetes + Gehren Guerin tumor volume, cm ³ 7 days 1.1 ± 0.1 ^* 2.6 ± 0.25 10 days 16.0 ± 1.8 ^* 23.6 ± 2.5 14 days 39.3 ± 3.8 ^* 50.4 ± 5.2 ascites there is No death of the first / last rat in the group, days 11/18 15/28 average life expectancy, days 15.8 ± 1.2 ^* 26.5 ± 2.3

* - significant differences between the main group compared to the control group, p <0.05.

In the control group of rats, Guerin's carcinoma began to be visualized at the same time as in the control: in 25% after 3 days, in 100% after 5 days.

After 1 week, the average tumor volume was 2.1 cm ³ , after 10 days the volume increased 9.7 times, after 2 weeks - another 2.5 times (see Table 1).

The first animal in the control group died after 15 days, the average lifespan of the rats was 26.5 days, the maximum - 28 days (see Table 1).

Consequently, the distinctive features of the tumor process of Guerin's carcinoma, developing against the background of induced diabetes mellitus, were: 1.6 times (p <0.05) shorter life expectancy of animals and a smaller volume of subcutaneous tumors: 7 days after inoculation - 2.4 times (p <0.05), after 10 days - 1.5 times (p <0.05), after 14 days - 1.5 times (p <0.05) (see Table 1).

Generalization of the malignant process of Guerin's carcinoma with metastatic lesions of the ovaries, kidneys, parietal and visceral peritoneum was established in 80% of the animals of the main group, withdrawn from the study in the pre-terminal state, with necropsy (see Figure 1).

Histological analysis revealed general signs of aggressive "behavior" of a subcutaneously grafted tumor, namely, metastatic lesions of internal organs and peritoneum with the formation of cords of tumor cells forming dense conglomerations, which led to a complete erasure of organ architectonics.

Attention was drawn to the significant blood filling of large and small blood vessels, in the lumens of which tumor cells were visualized (see Figure 1).

Visual control fabrics the ovary made it possible to establish complete tumor replacement of the parenchyma of the hormone-producing organ with the loss of the structure of the follicles from primordial to mature. At the same time, it was often possible to determine the false follicle-like structures formed by the tumor cells themselves, as an adaptation to the loss of the dominant function of the affected organ (see Figure 2).

The morphological study of the kidneys indicated the process of total tumor lesion of the organ. The high proliferative activity of carcinoma cells, confirmed by the presence of many figures of pathological mitosis in almost all fields of vision, was maintained by the necessary environmental conditions, namely, by the blood soaking of the kidney parenchyma.

This created a metabolic field with a high level of free radical processes that promote tumor progression. On the presented rat kidney preparations, significant blood vessels filling and hemorrhages in the parenchyma and connective tissue membrane were observed. The release of tumor cells, forming cords or separate fields with a dense arrangement of proliferating cells, completely destroyed renal structures due to the total growth of Guerin's carcinoma (see Figure 3).

The aggressive growth of Guerin's carcinoma grafted under the skin in female rats with an induced severe comorbid state in the form of diabetes demonstrated a complete loss of tissue protective barriers and the penetration of malignant cells not only into the parenchyma of various organs, but also into the peritoneum , as a single connective tissue defense system of the abdominal cavity.

On histological preparations of the peritoneum, extensive fields of blood filling were visualized in the immediate vicinity of the penetrating tumor cells. The scattered character of the penetration of single neoplastic cells gradually passed into the formation of cord structures, and then into actively proliferating pools of malignant cells, which aggregated and filled the entire space of the peritoneum (see Figure 4).

Thus, the reproduction of the model of alloxan diabetes in female nonlinear rats, preceding the inoculation of Guerin's adenocarcinoma, contributed to the generalization of the tumor process with hematogenous metastatic lesions of the internal organs, parietal and visceral peritoneum, the development of ascites, and a decrease in the life span of animals.

The technical and economic efficiency of the "Method for stimulating hematogenous dissemination of carcinoma in the experiment" is that alloxan diabetes provokes generalization of the tumor process in 100% of sexually mature female nonlinear rats, leading to the death of animals on average - after 16 days. The developed method can serve as a model for studying the role of diabetes mellitus in the pathogenesis of malignant growth, as well as for finding ways of drug treatment of this pathology. The method is economical and affordable.

Claims (1)

The method for stimulating hematogenous dissemination of carcinoma in the experiment is that in female nonlinear rats at the age of 3.5-4 months, diabetes mellitus is induced by a single intraperitoneal injection of alloxan at a dose of 150 mg / kg body weight, after 1 week against the background of a consistently high glucose level in Blood rats are inoculated with Guerin's carcinoma by injecting tumor suspension under the skin of the right scapula in a volume of 0.5 ml and diluting in physiological solution 1: 5.

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