Carcinogenesis - the process of turning a normal cell into a tumor cell under the influence of the mutations that accumulate in the cell. The cause of tumor cells is the accumulation of her mutation. The accumulation of cell mutations occurs as a result of the occurrence of genetic instability. The process of tumor development is divided into 3 main stages: initiation, promotion and progression. At the stage of initiation of cell receives the first mutational hit, which leads to disruption of its genetic stability. Most often, mutations are subjected to proto-oncogenes, genes-tumor suppressors, and genes governing DNA repair processes. At this stage there is an accumulation in the cell genetic damage that lead to an increase of the degree of malignancy. The next step in the transformation of cells in a tumor is promoted. This period has transformed as a result of mutations cells acquire a number of properties that help it to survive in the environment. They no longer respond to signals from the environment, acquire, auto- and paracrine stimulation signals of proliferation, the inhibition of apoptosis, genetic instability, changes in the morphology of the cells, the lack of replicative aging. Cells of tumour clone is constantly mutating under the pressure of selection by the immune system of the body. This leads to qualitative changes of the phenotype of tumor cells, the emergence is one of many tumor clones. This stage is called “tumor progression”. As a result of increasing tumor mass requires greater amount of nutrients. The stimulation of angiogenesis. By reducing the degree of affinity of the cells to the substrate and increase its mobility, there are secondary foci, metastases. The development of tumor process captures new areas in the body in Spite of the constant improvement of methods of therapy of tumors, the number of patients who achieve long-term remission is not great. So researchers are looking for ways for more complete and in-depth study of the pathogenesis of tumors, since this will facilitate the development of more effective approaches to therapy of tumors. This article briefly describes the main stages of tumor development.

Background. Flow cytometry (FC) algorithms of detection of minimal residual disease (MRD) are well standardized, and approximate to molecular biologic methods. However, besides informative leukemia-associated aberrant immunophenotype, which are selected taking into account a tumor phenotype at diagnostics stage, it is necessary to consider specificity of the provided taget therapy and its influence on a cell. Objective: to offer stable combinations of antigens to identify B-cell precursors in patients on therapy of blinatumomab. Materials and methods. Clinical observation of patient G. 4 years old with B-cell precursors acute lymphoblastic leukemia (ALL) (pre-pre-B immunosubtype), whom after 3 bloks of reinduction therapy, taking into account MRD-positive status, blinatumomab was appointed as a monotherapy. Tumor immunophenotype was characterized in details by FC protocol according to EuroFlow in debute and relapse of the disease. MRD monitoring was provided by 8-color FC taking into account personalized leukemia-associated aberrant immunophenotypes. Results. In patient with B-cell precursors ALL received blinatumomab, the strategy of MRD monitoring was changed. Due to the lack of CD19 expression, identification of B-cell precursors was based on expression of cyCD22 in combination with nuclear TdT and CD10. Conclusion. In case of blinatumomab’s appointment during B-cell precursors ALL therapy, it is necessary to change the strategy of B-cell precursors identification, due to the lack of CD19 expression. Detection of B-cell precursors should be provided by assessment of other pan-B lineage antigens. First of all, it is cyCD22 or cyCD79a in combination with nuclear TdT and CD10, within the limits of nucleated cells of the sample.

Objective is the investigation of messenger RNA quantitative expression profiles of potential target genes among disseminated gastric cancer cases. Materials and methods. Quantitative real-time polymerase chain reaction on paired tumor-normal samples. Results. The most frequently (25-41 % of cases) an increased level of messenger RNA in the tumor with respect to normal tissue was observed for the genes of TGF-ß (transforming growth factor ß), NRP-1 (neuropiline 1) and VEGF (vascular endothelial growth factor) family genes. For the first time a correlation between the expression levels of the three genes: NRP-1, TGF-ß and VEGFR-2, and the inverse correlation of the levels of VEGF and bFGF gene expression were found. Conclusion. The revealed correlation between the expression of TGF-ß, NRP-1 and VEGFR-2 genes is apparently due to the interaction of NRP-1 with the products of two other genes and may be associated with a high metastatic potential of the progressing tumor in disseminated gastric cancer. The observed inverse correlation of the VEGF-A and bFGF gene expression may indicate the stimulation of angiogenesis in the tumor with reduced activity of the VEGF pathway by activating the bFGF signaling pathway. The results obtained should be taken into account under targeted therapy.

Background. Epithelial-mesenchymal transition (EMT) is a factor related to metastatic potential of tumor cells. The most distinguishing feature of this transformation is expression of protein vimentin, which is not common for epithelial cells. Data of EMT level and clinical significance of the marker is ambiguous in prognosis of tumor different localization including ovarian cancer. Objective is characterization of EMT in ovarian cancer tissue based on quantitative analysis of co-expression level of epithelial cytokeratins and mesenchymal cells marker vimentin. Materials and methods. A quantitative assessment of co-expression level of cytokeratins and vimentin was performed by double immunofluorescence staining method (58 surgery specimens of ovarian cancer stage III), associated with flow cytometry. Results. Double immunofluorescence staining method, developed and used in the current study, was used for quantitative assessment of EMT level based on value of cytokeratin and vimentin co-expression in epithelial cells. Epithelial cells co-expressed these markers, were detected in 100 % tumor investigated with individual value differences from 10 to 86 %. Average co-expression level of cytokeratins and vimentin in subgroups with high and low level value related to median 42 % significantly varied and were 28,5 ± 7,5 and 56,3 ± 11,8 % (p = 0,02) respectively. Conclusions Serous ovarian cancer is molecular heterogeneous group with principal differences in level of EMT tumor phenotype between various patients. In half of the cases the disease is characterized by high metastatic potential of tumor cells. Co-expression of cyto-keratins and vimentin in all the tumors investigated is evidenced clinical significance of this molecular characteristic in ovarian cancer pathogenesis.

Background. In recent years, interest in hormonal treatment of ovarian cancer has revived and a number of fundamental questions associated with the expression in these tumors of different types of estrogen receptors (ER) - ERa and ERß - have arisen. Objective: to answer the questions, what is the frequency and level of expression of ERa and ERß in the tissue of ovarian cancer and is it possible co-expression of ERa and ERß in different and/or in the same tumor cells. Materials and methods. A comparative quantitative assessment of the frequency and level of expression of ERa and ERß in the tissue of ovarian cancer (a total of 20 samples) was carried out using the immunofluorescence method and flow cytometry, including the method of double fluorescent staining developed by the authors. Results. ERß expression was found in all ovarian cancer samples, but there are both ERa+ and ERa^- tumors. In most ERa+ tumors (69 % of cases), a low (<40 %) level of ERa expression was observed. Moreover, in the study of tumors with a high level of expression of both ERa and ERß, co-expression of the markers in the same cells of the examined tumors was revealed. Conclusions. In the ovarian cancer tissue, different types of ER - ERa and ERß - can be expressed in different tumor cells, as well as co-expressed both in different and in the same tumor cells.

Background. Epigenetic changes of TSG are supposed as the most fine and active genes regulation mechanism in particular breast cancer (BC) genes pathway development. The most valuable results are awaited for methylation role of genes located on the short arm of chromosome 3 with also MGMT gene (10q26) in BC pathogenesis because of their ambiguous data for methylation status in tumors. Objective: to illustrate the specific methylation role of the RASSF1A, SEMA3B, RARß2, RHOA, GPX1, USP4, DAG1, NKIRAS1 and MGMT genes promoter regions in BC pathogenesis. Materials and methods. Sample set of 174 BC patients consists of tumor and surrounding histologically normal tissue that were collected and clinically characterized in the N.N. Blokhin National Medical Research Center of Oncology. Two substantive methods were used to evaluate DNA methylation status. To analyse RASSF1A, SEMA3B, RARß2 and MGMT genes methylation we used polymerase chain reaction specific for the methylated allele. Whereas for analyses RHOA, GPX1, USP4, DAG1, NKIRAS1 promoter regions genes methylation status was used methyl sensitive restriction analyses with 2 methyl sensitive endonuclaeses HpaII and HhaI with subsequent polymerase chain reaction. Results. A statistically significant high frequency of RASSF1A, SEMA3B, RARß2, and MGMT genes methylation in epithelial breast tumors compared with histologically normal tissue from the same patients was shown. Significant correlation of RARß2 and MGMT genes methylation frequency considering the different clinical and morphological characteristics of the malignant process was revealed. The statistically significant relationship between methylation of RASSF1A, RARß2 and MGMT genes and patient survival is shown for the first time. Conclusion. The findings of epigenetic changes in the luminal BC supplement the “molecular picture” of this cancer and contribute to an understanding of its pathogenesis. The revealed features of investigated genes methylation can find clinical application for the development of modern approaches to prognosis, prevention and choice of tactics for treatment of BC in females of the Moscow region.

Objective: to evaluate the prospects of the glycosides of indolocarbazole containing amino acid residues as potential antitumor compounds. Materials and methods. For 32 compounds by structural formulas using the methods of chemoinformatics, a number of molecular descriptors and the probability of manifestation of various types of biological activity were calculated, the cytotoxic activity was evaluated in vitro by methylthiazole tetrazolium (MTT) assay using five human tumor cell lines. Results. For the studied amino acid derivatives of glycosides of indolocarbazole, a high probability of antitumor activity with a low probability of cytotoxic activity in vitro is predicted by computer method. Low cytotoxic activity was confirmed in the MTT test on 5 cell lines. Computer methods were used to predict the mechanisms of possible antitumor activity and to calculate a number of molecular descriptors that are important for the qualification of substances as potential drugs. Conclusion. It is expedient to study the antitumor activity of amino-acid derivatives of glycosides of indolocarbazole in experiments on animals with transplanted tumors.

Background. Drugs of nitrosourea class are actively and successfully administered in oncology practice. However, at present, the search for new antitumor agents of this class is very urgent. Objective: to examine in vivo antitumor activity of ormustine, a new Russian drug from alkylnitrosourea class, against solid transplantable murine tumors: melanoma B16 and epidermoid Lewis lung carcinoma. Materials and methods. The assessment of antitumor activity of ormustine and a reference drug mustophoran (Les Labolatories Servier, France) was carried out in B6D2F1 mice. Ormustine was administered intravenously at a single dose of 50-135 mg/kg. Mustophoran was administered intravenously at a dose of 32 mg/kg twice (on days 2 and 9) and 3 times at a dose of 25 mg/kg (on days 2, 6 and 9). The follow-up period lasted till the death of animals. The antitumor effect of agents was assessed by the tumor growth inhibition and increase in life span of experimental mice compared to control animals. Results. It has been defined that the single intravenous dose of ormustine (125 mg/kg) is therapeutic for mice bearing melanoma B16 and epidermoid Lewis lung carcinoma. Conclusions. Ormustine possesses high antitumor effect against solid transplantable murine tumors. Ormustine is not inferior to mustophoran in the therapeutic effect against melanoma B16.

Background. Currently, the drugs, acting directly on tumor molecular or cellular targets, are actively designed. Target antitumor drug aimpila is atractyloside alpha-fetoprotein noncovalent complex. The development of this formulation is based on the ability of alpha-fe-toprotein, as a transport protein, to deliver cytotoxic agents into the cells that have alpha-fetoprotein receptors. Objective: to investigate the toxicity of aimpila in chronic experiment on rabbits. Materials and methods. The study was performed in male and female “Soviet chinchilla” rabbits. Final drug formulation (aimpila in gelatin capsules) was administrated per os at 1 and 10 therapeutic doses (0.05 and 0.5 mg/kg respectively) for 30 days with interval of 24 h. During the study dynamics of body weight, hematological parameters, blood biochemical parameters, electrocardiography and urinalysis were performed for all animals. Five animals in each group were sacrificed in days 1 and 30 post treatment, then their internal organs were subjected to histological evaluation. Results. The study demonstrates that the treatment with aimpila for 30 days in single therapeutic dose of 0.05 mg/kg had no effect on the clinical and laboratory parameters or the morphological structure of the internal organs of rabbits. Signs of hepato-, nephro-, cardio-and gastrointestinal toxicity were found in group of rabbits, treated with high dose of drug. The structural damages in liver were clinically supported with a significant increase of aspartate aminotransferase level in serum. Pathological changes in the kidneys were accompanied by a significant increase of urobilinogen and ketone bodies levels in the urine. Signs of cardio- and gastrointestinal toxicity were documented only by microscopic pathology observation. These abnormalities were reversible within 30 days. Conclusions. Aimpila formulation displayed dose-dependent and reversible toxicity and can be recommended to further investigation.

Background. Over the last years the studies have increased interest in screening antitumor and anti-angiogenic substances that block several mechanisms of angiogenesis activation in tumors. A great attention is paid to development of effective and low toxic drugs as inhibitors of angiogenesis which are derived from herbal raw material. The article is devoted to the results of standardization of the dosage form of dimeric macrocyclic tannin (DMT) obtained from Chamerion angustifolium (L.) Holub in N.N. Blokhin National Medical Research Center of Oncology, which has a great potential as an antiangiogenic agent. Objective: to determine quality criteria for standardization of the drug “DMT, lyophilisate for preparation of solution for injections 100 mg”. Materials and methods. The study used “DMT, lyophilisate for preparation of solution for injections 100 mg” and DMT substance. Methods: spectrophotometry, infrared spectroscopy, high performance liquid chromatography, potentiometry, polarimetry. Results. Quality criteria for lyophilized DMT dosage form were determined with the account of Russian State Pharmacopoeia (XIII edn.) requirements to the drugs for injections and methods for their evaluation were defined. Conclusions. Laboratory studies demonstrated that the determined quality criteria and the defined methods for their evaluation are feasible for adequate quality control of dosage form “DMT, lyophilisate for preparation of solution for injections 100 mg”.

Background. Current work is devoted to the study in vivo of concentration and selectivity of accumulation of infrared photosensitizer (PS) hydroxyaluminium tetra-3-phenylthiophthalocyanine in liposomal form in intramuscularly and subcutaneously transplanted mice tumor models in comparison to normal tissues. Objective: to study the level and selectivity of accumulation of hydroxyaluminium tetra-3-phenylthiophthalocyanine liposomal form on mice tumor models in order to optimize the transplantation approach and the starting of photodynamic treatment. Materials and methods. A range of transplantable mice tumors was used in the study: solid carcinoma Ehrlich (ELD) and solid sarcoma S-37, epidermoid Lewis lung carcinoma (LLC) and colon adenocarcinoma (AKATOL). For the assessment of concentration of PS in tissues was evaluated by fluorescence spectroscopy in vivo. Results. The optimum transplantation approaches were shown to be as follows. Solid carcinoma Ehrlich (ELD) provided the highest accumulation of PS when transplanted intramuscularly. Five hours after administration concentration of PS in tumor achieves more than 7 mg/kg, with selectivity in comparison to normal tissue 3 : 1. The maximum concentration of PS in sarcoma S-37 was observed with subcutaneous transplantation, achieving at 5 h after administration the value of 5.4 mg/kg with selectivity of accumulation 4.3: 1. Both LLC and AKATOL showed optimum results with intramuscular transplantation. Maximum concentration of PS in LLC was observed 5 h after administration, achieving 7.5 mg/kg with selectivity exceeding 4. Concentration of photosensitizer in AKATOL 7h post administration achieved 6.8 mg/kg with selectivity about 2. Conclusions. Liposomal form of PS with intravenous administration selectively accumulates in tumors. The obtained experimental data allows to recommend the method of listed tumors models transplantation for the studies of PS.

Introduction. One of the modern approaches to development of antitumor drugs is based on oriented search of specific tumor cells molecular targets inhibitors. The application of such therapeutic agents will improve selectivity of action and decrease side effects of antineoplastic therapy. Novel antitumor multitargeted drug anthrafuran (LCTA-2034), obtained in Gause Institute of new antibiotics, represents a derivative of anthra[2,3-b]furan-3-carboxamide. Compound exhibits pronounced antitumor activity in vivo. Objective. The objective of the present study was to investigate the toxicity of LCTA-2034. Materials and methods. Toxicological study was performed in male outbred rats. The drug was administrated intraperitoneally at the total doses of MTD and LD₅₀ (14 x 3 mg/kg or 14 x 4.5 mg/kg with 24-h interval). Dynamics of body weight, hematological parameters, blood biochemical parameters, electrocardiography and urinalysis were performed for all animals. 5 animals in each group were sacrificed 1 and 30 days post treatment. The mass coefficients of heart, kidneys, liver, spleen and thymus were calculated. The internal organs were subjected to histological evaluation. Results. The results of the study demonstrate that the intraperitoneal injections of LCTA-2034 don't produce any changes in examined clinical-laboratory parameters. The treatment with LCTA-2034 in total dose of MTD had no effect on morphological structure of the internal organs of rats. The reversible structural damages in liver, kidneys and small intestine were found in group of rats, treated with high dose of the drug. Signs of cardiotoxicity were documented by microscopic pathology observation on day 30 post treatment in individual animals. Conclusion. Dose dependence and reversibility of toxic effects of LCTA-2034 allows us to recommend it to further advance.

Background. The addition of active metabolites (in particular, amino acids) to the molecule affects the physicochemical and prodrug properties of derivatives of indolocarbazoles. Using computed chemoinformatics, probability antitumor activity of amino-acid derivatives of glycosides of indolocarbazol (AADGI) is predicted with low probability of their cytotoxic activity in vitro. Based on these data, a study of these compounds in vivo is conducted. Objective: the assessment of AADGI as potential antitumor medications. Materials and methods. Research antitumor activity of AADGI was done using murine tumor models - cervical cancer CC-5. Investigated compounds were injected to mice СВА abdominally 5-times daily with interval of 24 h. Observation of animals were continued till their death. Antitumor effect of compounds was assessed by criteria of tumor growth inhibition and increase in life expectancy of mice comparing to control animals. Results. The optimal dose for these series of compounds was titrated and this dose is 100 mg/kg. Antitumor activity of AADGI was assessed on CC-5. Conclusions. Based on data received we suggest an extended study in vivo of antitumor qualities of selected 5 leader AADGI.