Correlation between Expression of KLF5 and ZEB1 Transcription Factor Genes in Pancreatic Cancer.

The mRNA content of the transcription factors KLF5 and ZEB1 was studied in pancreatic tumor tissues and in fetal and normal pancreas. Transcription of these factors was not high and similar in normal and fetal pancreatic tissues but greatly increased in the pancreatic ductal adenocarcinoma tissues. A significant positive correlation between the KLF5 and ZEB1 transcription levels in the pancreatic tumor tissues was observed.

PDX1: A Unique Pancreatic Master Regulator Constantly Changes Its Functions during Embryonic Development and Progression of Pancreatic Cancer.

Multifunctional activity of the PDX1 gene product is reviewed. The PDX1 protein is unique in that being expressed exclusively in the pancreas it exhibits various functional activities in this organ both during embryonic development and during induction and progression of pancreatic cancer. Hence, PDX1 belongs to the family of master regulators with multiple and often antagonistic functions.

Dependence of expression of regulatory master genes of embryonic development in pancreatic cancer cells on the intracellular concentration of the master regulator PDX1.

Exogenous expression of the gene encoding the pancreatic master regulator PDX1 in cell lines with different degrees of differentiation of pancreatic cancer cells is accompanied by changes in the expression of known master genes involved in cancer progression. In BxPC3PDX+ cells, as compared to BxPC3PDX-, we detected an increased expression of the following genes: NKX6.1 (2 times), NR5A2 (2.5 times), KLF5 (1.8 times), ZEB1 (3 times), and ONECUT1 (1.3 times), as well as a decreased expression of MUC1 and SLUG genes (3 and 2 times, respectively). In PANC1PDX+ cells, as compared to the control PANC1PDX- cells, we detected a decreased expression of ISL1 (2 times) and an increased expressed of KRT8 (2 times) and MUC1 (by 30%). In the high-grade cell lines (including the BxPC3 line studied), the total content of sites containing the marks of active enhancers was higher than that in the low-grade cell lines (PANC1).

[Pioneer Transcription Factors in Normal Development and in Carcinogenesis].

Pioneer transcription factors constitute a heterogeneous group of regulatory proteins of animals, which, unlike other transcription factors, are able to recognize and bind target DNA sequences within closed chromatin. This binding can change the local chromatin structure and facilitate binding of other proteins, thus establishing competence for gene expression. The ability to bind silent genes in the closed environment makes the pioneer factors very useful in the processes leading to cardinal alteration of cell phenotype, such as differentiation in embryonic development or cell reprogramming. These proteins can remain bound to target sequences during mitotic division, and due to this probably take part in the maintenance of cellular memory. Apparently, pioneer transcription factors are active participants in carcinogenesis and maintenance of tumor cell phenotype, although their role in these processes needs additional research. It is reasonable to suppose that a further study will help to shed more light on the genetic processes in embryonic development, increase the efficiency of cell reprogramming and also develop new approaches to diagnostics and therapy of cancer diseases.

[ADULT STEM CELLS AND CELLS OF MALIGNANT ORIGIN. PART II].

Recent data on adult stem cells are reviewed. According to the present dominant paradigm, it is most probable that cancer predisposition arises or cancer is initiated in these cells.

[ADULT STEM CELLS AND CELLS OF MALIGNANT ORIGIN. PART I].

Recent data on adult stem cells are reviewed. According to the present dominant paradigm, it is most probable that cancer predisposition arises or cancer is initiated in these cells.

[Master Transcription Regulators Specifying Cell-Lineage Fates in Development As Possible Therapeutic Targets in Oncology].

The transformation of normal precursors into cancer cells is an intricately regulated, multistep process. The master regulatory genes that play a crucial role in the process of organism development may also play a key role in carcinogenesis. From such a point of view, cancer is not simply a genetic disease that is due to a progressive accumulation of mutation--it is also a disorder of the developmental system of the tissue in which cancer emerges. Master regulators and their genes disturb stem cell differentiation upon mutation and thus may serve as targets for cancer therapy, in addition to the classic oncogenes and suppressors of tumor formation. This review is an attempt to give a modern concept of master genes and their functions in adult stem cells of the organism and in carcinogenesis, with pancreatic cancer as an example.

[Comparative analysis of activity of different promoters for NIS gene expression in melanoma cells].

Development of targeted drug delivery system is key problem of cancer gene therapy. To ensure specific delivery of these therapeutic compounds to the tumor it is preferable for therapeutic gene expression to occur predominantly in cancer cells. Therefore, when testing drug in vivo, it is necessary to study distribution of therapeutic gene expression products in different tissues of the organism. Sodium iodide symporter (NIS) is attractive reporter because its tissue level is easily quantitatively detected by noninvasive imaging methods. Different promoters are used to direct expression of therapeutic genes in tumor cells: strong nonspecific, moderate tissue-specific and tumor-specific. Tumor-specific promoters function in wide range of tumor cells, however they are relatively weak. Relationship between promoter and sodium iodide symporter activity is unclear to date. In this report we examined activity of different promoters in two melanoma cell lines, functional activity of NIS driven by these promoters, also we compared promoter strength and NIS activity. We demonstrated that in spite of strong differences in promoter activity functional activity of NIS directed by these promoters varies weakly. Relatively weak melanoma-specific promoter directs high NIS activity in melanoma cell, however weaker cancer-specific promoters drive high NIS activity only in certain melanoma cell line.

[Quantitative comparison of expression for genes linked in bicistronic vectors via ires or 2A-peptide of porcine teschovirus-1 sequence].

Simultaneous expression of multiple target genes is often required in biotechnology. Multicistronic vectors coding for several proteins are being actively developed for this purpose. In commercially available vectors different variants ofencephalomyocarditis virus internal ribosome entry site (IRES EMCV) are used most often. However, many researchers consider that utilization ofself-cleaving 2A peptides sequences within multi- and bicistronic vectors is more promising. In this work, we compared the efficiency of gene expression in cells transfected with bicistronic vectors based on IRES EMCV and 2A peptide sequence derived form porcine teschovirus-1 (P2A). Efficiency ofgene expression was determined in three mammalian cell lines by measurement of co-expression levels of genes coding for RFP and EGFP proteins linked by IRES or P2A sequence. Higher level oftransgene expression was exhibited by cells transfected with the vector containing the 2A peptide sequence.

[The evaluation of eosinophilogram of peripheral blood in children with eosinophilia].

The need in study and interpretation of eosinophilograms in children with allergic diseases is conditioned by higher rate of eosinophilia, large specter of morphologic and functional signs of eosinophils, dependence of indicators from character of clinical course of disease, presence of complications and schemes of treatment. The level of laboratory techniques applied in routine clinical practice to evaluate morphological and functional characteristics of eosinophils is not developed enough. The implementation of such modern high-tech techniques as computer morphometry, highly sensitive and highly specific modifications ELISA, which are applied to detect associated with eosinophilia cytokines, chemokines and growth factors make it possible to approach to this issue at the new qualitative level.

[The analysis and forecast of the demographic situation tendencies in the Republic of Udmurtiya].

The unfavorable demographic situation tendencies in the Republic of Udmurtiya are characterized by the decrease of population size and incidentally the regressive type of age structure is supported. The evolution of demographic processes (natality, mortality, life expectancy) affected the age gender structure of population of the republic. The reproduction of population and generations replacement decelerated in the region with low population density

Cellular and molecular phenotypes of proliferating stromal cells from human carcinomas.

BACKGROUND: Stromal cells are a functionally important component of human carcinomas. The aim of this study was to obtain and characterise primary cultures of stromal cells from human carcinomas and the corresponding surrounding normal tissue. METHODS: Primary stromal cell cultures from tumours of lung, oesophagus and pancreas were obtained using a mild tissue dissociation method and a medium for culturing mesenchymal cells. Immunofluorescence staining and western blotting were used to analyse the expression of differentiation markers and selected known oncoproteins in the cell cultures obtained. RESULTS: A panel of stromal primary cultures was prepared from different human tumours and from matched normal cancer-free tissues. The in vitro proliferative potential of tumour-associated fibroblasts was shown to be higher than that of matched normal stromal cells. A mutational analysis of the TP53 and KRAS2 genes in a number of stromal cultures did not reveal known mutations in most cells of the cultures studied. Western blot analysis showed that stromal cells of lung tumours were characterised by a statistically significantly lower expression level of the p16 protein as compared with that in normal lung stromal cells. An important finding of our study was that, according to immunofluorescence assay, a fraction of fibroblast-like vimentin-positive cells in some tumour and normal stromal cell cultures expressed an epithelial marker - cytokeratins. CONCLUSIONS: Proliferating stromal cells from the carcinomas studied proved to be genetically normal cells with altered expression profiles of some genes involved in carcinogenesis, as compared with normal stromal cells. Epithelial-mesenchymal transition may lead to the emergence of transdifferentiated fibroblast-like cells in tumour stroma and in the tumour-surrounding tissue.

Enhancer element potentially involved in human survivin gene promoter regulation in lung cancer cell lines.

We have revealed evolutionarily conserved regions in a 4500-bp DNA sequence 5'-adjacent to the survivin (BIRC5) gene. In the transcribed region of the BIRC5 gene we have detected and characterized in detail a 3'-fragment of the CpG island that stimulated in enhancer-like way the gene promoter activity in normal cells and in a number of cancer, in particular lung cancer, cell lines. When added to the initial 1498-bp survivin promoter region, a transcribed DNA fragment of a CpG island approximately twofold enhanced the promoter activity in cancer cells and in normal lung fibroblasts. The observed effect did not depend upon the orientation of the fragment and distances between the fragment and the transcription initiation site. In the case of a heterologous SV40 virus promoter, the effect was less pronounced. In addition to earlier reports, the results provide new information on the BIRC5 gene expression regulation and also demonstrate that this gene exon sequences can play a significant role in BIRC5 gene expression regulation. The data provide another possibility to increase survivin promoter activity without changing its cancer specificity for application in cancer (in particular, lung cancer) gene therapy.

Identification of some human genes oppositely regulated during esophageal squamous cell carcinoma formation and human embryonic esophagus development.

Here we directly compared gene expression profiles in human esophageal squamous cell carcinomas and in human fetal esophagus development. We used the suppression subtractive hybridization technique to subtract cDNAs prepared from tumor and normal human esophageal samples. cDNA sequencing and reverse transcription polymerase chain reaction (RT-PCR) analysis of RNAs from human tumor and the normal esophagus revealed 10 differentially transcribed genes: CSTA, CRNN, CEACAM1, MAL, EMP1, ECRG2, and SPRR downregulated, and PLAUR, SFRP4, and secreted protein that is acidic and rich in cysteine upregulated in tumor tissue as compared with surrounding normal tissue. In turn, genes up- and downregulated in tumor tissue were down- and upregulated, respectively, during development from the fetal to adult esophagus. Thus, we demonstrated that, as reported for other tumors, gene transcriptional activation and/or suppression events in esophageal tumor progression were opposite to those observed during development from the fetal to adult esophagus. This tumor 'embryonization' supports the idea that stem or progenitor cells are implicated in esophageal cancer emergence.

[Core promoters as an example of the evolution of views on molecular mechanisms of vital activity under the impact of whole-genome information].

DNA sequences of a large number of animal genomes, combined with the information on new classes of regulatory elements traditionally viewed as intergenic, led to the revision of the concept of the genome as a linear sequence of genes with their promoters spaced by distinct intergenic regions. Instead, there emerged a conception of 'transcriptional landscape' characterized by the practical absence of boundaries between what was commonly considered genes. The concept of the core promoter, the main transcriptional cis-acting element, was also dramatically changed. The knowledge of the mechanisms of functioning of this central element of the cellular transcription system underlies the understanding of metazoan transcription in general. The review attempts to summarize the data on core promoters obtained in the last 7-10 years and to trace the evolution of the conception of them. This evolution led finally to the understanding that core promoters are active participants of the transcription regulation process rather than just passive scaffold for assembling preinitiation transcription complexes.

[Functional analysis of the HERV-K LTR residing in the KIAA1245/NBPF subfamily].

Long terminal repeats (LTRs) of human endogenous retrovihuses (HERs) might affect transcription regulation of neighboring genes. In our previous study, we showed that the solitary LTR residing in the KIAA1245/NBPF gene subfamily displayed high enhancer activity in a transformed embryonal carcinoma cell line Tera1. In this study, we performed a functional dissection of the LTR and studied its deletion series. Using transient transfection assay, we confirmed the ability of the LTR to drive the expression of the luciferase reporter gene in Teral cells. At the same time, in two other transformed cell lines tested, NGP and NT2/D1, the full-size LTR and its fragments showed no or low enhancer activity, thus demonstrating cell type specificity of the LTR enhancer activity. The functional dissection of the LTRrevealed a specific region within the U3 part appeared to be responsible for the enhancer properties. We showed that the identified enhancer was able to work in a highly cell type specific manner. The data obtained are in line with the hypothesis suggesting that KIAA1245/NBPF LTR may affect the regulation of the KIAA1245/NBPF subfamily genes transcription.

[Registry-based comparison of multiple sclerosis epidemiology trend data in 1999 and 2019: the case of Yaroslavl]. / Dinamika osnovnykh epidemiologicheskikh pokazatelei rasseyannogo skleroza po rezul'tatam sravneniya registrov patsientov 1999 i 2019 gg. v Yaroslavle.

OBJECTIVE: To compare the epidemiological indicators of multiple sclerosis (MS) in Yaroslavl when comparing the 1999 and 2019 registers to study the pathomorphism of the disease in this territory. MATERIAL AND METHODS: During the work, the data of the 1999 and 2019 registers were used, including the age of the debut, the date of diagnosis, the form of the disease, clinical characteristics, the treatment received and its duration. In 1999, 257 patients living in the city of Yaroslavl (155 women and 102 men) were included in the MS registry with a reliable diagnosis of MS according to Poser's criteria with confirmation according to neuroimaging data. In 2019, 479 people living in the territory of Yaroslavl (342 women and 137 men) were included in the register with a diagnosis of MS based on the criteria of MacDonald 2005, 2010, 2017. As of 01.01.19, 970 patients (530 women and 440 men) were included in the patient register of the Yaroslavl region. RESULTS AND CONCLUSION: Clinical and epidemiological review of Yaroslavl MS Registry data in 1999 and 2019 showed significant changes in disease pattern. The prevalence rate increased from 42.6 to 78.5 cases per 100,000 people. The morbidity rate rose from 1.58 to 3.28 cases per 100,000 people. The reasons for the increase are improvement in the diagnostic quality, new diagnostic criteria and the true growth of prevalence and morbidity. The use of disease modifying drugs (DMDs) has extended «the time to EDSS 3,0¼ by 4 years, «the time to EDSS 6,0¼ by 5-8 years.

[Expression of FTL and FTH genes encoding ferretin subunits in lung and renal carcinomas].

The level of ferritin in serum is known to be increased frequently in most human cancers. Ferritin consists of the heavy and light chains, encoded by FTL and FTH genes. The analysis of the EST database showed that the level of FTL and FTH mRNA is decreased in lung squamous cell carcinomas as compared to the normal tissues, no change in the mRNA level was observed in clear cell renal cell carcinoma. Using real-time PCR we estimated the mRNA level of these genes in primary tumors. It was shown significant and frequent decrease of FTL and FTH mRNA level in lung squamous cell carcinoma: on the average by 11 and 9 times in 83% (33/40) and 73% (11/15) of cases, respectively. In clear cell renal cell carcinoma the changes were not so marked both with respect to the level of decrease (on the average 6 and 3 times) and to its frequency (58 and 27%). In the present work it has been shown for the first time that the FTL mRNA is frequently down-regulated even at the early stages of lung squamous cell carcinoma in all studied samples. This fact permits to consider this gene as potential oncomarker of early diagnosis. The FTL mRNA content may be quantified by non-concurrent hybridization on expression DNA microarrays. The possible causes of a serum ferritin increase in lung cancer and renal cancer are discussed.

[Structure and functions of isoforms of polyfunctional tumoral suppressor PML].

Polyfunctional protein PML contributes significantly in vital activity of cell. 11 isoforms of PML differ from one another by C-terminal domain. In spite of intensive research into the protein, the role of the isoforms in cellular processes remains obscure. In addition, the literature contains various names of the isoforms. The goal of this work was to review the structure of the PML gene, variants of alternative splicing of mPNA, and domain organization of corresponding protein forms. The PML isoforms were classified and functional specificity of each PML isoform was characterized: contribution to gene transcription, contribution to cell apoptosis, cell growth, immune response, formation of nuclear bodies.