[Novel Genes Associated with the Development of Carotid Paragangliomas].

Carotid paragangliomas (CPGLs) are rare neuroendocrine tumors of the head and neck. "Germline" and somatic mutations in a number of genes were shown to be associated with the development of CPGLs; however, molecular mechanisms of the tumor pathogenesis have not been fully understood. In the work, we have used whole exome sequencing data of 52 CPGLs obtained earlier. Using MutSigCV, the search for genes with high mutation rate was performed. Thirty four genes (MADCAM1, SARM1, ZFPM1, CTDSP2, DSPP, POTED, ANP32B, FRG2B, BAGE3, CCDC89, ACOT2, KRTAP10-1, ATXN1, GXYLT1, MUC2, AQP7, TMPRSS13, KRTAP4-3, PRR21, PSPH, PLBD1, ZNF595, IGSF3, PRR16, FAM157A, KCNJ12, HYDIN, IGFBP2, KIAA1671, DISC1, MUC6, XKR3, HRNR, and MUC4) potentially associated with the CPGL initiation and progression were revealed. The involvement of these genes in the pathogenesis of CPGLs was first shown, and possible mechanisms of their participation in that were discussed.

[CAX3 Gene is Involved in Flax Response to High Soil Acidity and Aluminum Exposure].

Understanding the molecular mechanisms of plant response to unfavorable conditions is necessary for the effective selection of tolerant genotypes. Earlier, using high-throughput transcriptome sequencing of flax plants after exposure to aluminum ions (Al^(3+)) and high soil acidity, we detected stress-induced alteration in the expression of several genes, including CAX3, which encodes Ca^(2+)/H^(+)-exchanger involved in calcium ion transport. Here we describe CAX3 mRNA levels in flax cultivars either tolerant (Hermes and TMP1919) or sensitive (Lira and Orshanskiy) to Al^(3+). Stress-induced increased expression of CAX3 was detected only in aluminum-tolerant flax cultivars. The product of CAX3 gene may participate in flax response to high soil acidity and high Al^(3+) concentration through Ca^(2+)-mediated intracellular regulation.

[Transcription Factor SAP30 Is Involved in the Activation of NETO2 Gene Expression in Clear Cell Renal Cell Carcinoma].

Clear cell renal cell carcinoma (ccRCC) is a common oncourological disease with a high mortality level. The incidence of this type of cancer is constantly increasing, while molecular mechanisms involved in the disease initiation and progression remain far from being fully understood. A problem of the search for novel markers is crucial for improvement of diagnosis and therapy of ccRCC. We have previously found that the disease is characterized by increased expression of the NETO2 gene. In the present study, we showed that isoform 1 (NM_018092.4) makes the main contribution to the upregulation of this gene. Using original CrossHub software, "The Cancer Genome Atlas" (TCGA) project data were analyzed to identify possible mechanisms of NETO2 gene activation in ccRCC. The absence of significant contribution of methylation to the increase of mRNA level of the gene was observed. At the same time, a number of genes encoding transcription factors, which could potentially regulate the expression of NETO2 in ccRCC, were identified. Three such genes (MYCBP, JMY, and SAP30) were selected for the further analysis of their mRNA levels in a set of ccRCC samples with quantitative PCR. We showed a significant increase in mRNA level of one of the examined genes, SAP30, and revealed its positive correlation with NETO2 gene expression. Thus, upregulation of NETO2 gene is first stipulated by the isoform 1 (NM_018092.4), and the probable mechanism of its activation is associated with the increased expression of SAP30 transcription factor.

[Suppression of NR0B2 gene in Clear Cell Renal Cell Carcinoma Is Associated with Hypermethylation of Its Promoter].

Clear cell renal cell carcinoma (ccRCC) is a common urologic malignancy. Understanding of the transcriptional regulation of oncogenes and tumor suppressor genes involved is critical for the development of the treatments for renal tumors. Using ccRCC subdivision of the TCGA dataset, we identified NR0B2 encoding orphan nuclear receptor as a tumor suppressor candidate in renal tissue. In independent cohort of primary renal tumors, quantitative PCR experiments confirmed significant suppression of NR0B2 mRNA in 86% of ccRCC samples studied. In 80% of these cases, we detected the hypermethylation of the NR0B2 pro-moter region. These results suggest that NR0B2 is a tumor suppressor gene in ccRCC, and that the hypermethylation of promoter region is the main mechanism of its downregulation.

[Overexpression of microRNAs miR-9, -98, and -199 Correlates with the Downregulation of HK2 Expression in Colorectal Cancer].

Glycolysis activation is one of the main features of energy metabolism in cancer cells that is associated with the increase in glycolytic enzyme synthesis, primarily, hexokinases (HKs), in many types of tumors. Conversely, in colorectal cancer (CRC) the decrease in the expression of HK2 gene, which encodes one of the key rate-limiting enzyme of glycolysis, was revealed, thus, the study of the mechanisms of its inhibition in CRC is of particular interest. To search for potential microRNAs, inhibiting the expression of HK2 in CRC, we have performed the analysis of data from "The Cancer Genome Atlas" (TCGA) and five microRNA-mRNA target interaction databases (TargetScan, DIANA microT, mirSVR (miRanda), PicTar, and miRTarBase) using original CrossHub software. Seven microRNAs containing binding site on mRNA HK2, which expression is negatively correlated with HK2 expression, were selected for further analysis. The expression levels of these microRNAs and mRNA HK2 were estimated by quantitative PCR on a set of CRC samples. It has been shown, that the expression of three microRNAs (miR-9-5p, -98-5p, and -199-5p) was increased and correlated negatively with mRNA level of HK2 gene. Thus, downregulation of HK2 gene may be caused by its negative regulation through microRNAs miR-9-5p, -98-5p, and -199-5p.

[Biomarkers of prostate cancer sensitivity to the Sendai virus].

Metastatic prostate cancer is often associated with either primary or intractable castration-resistant prostate cancer (CRPC), thus justifying the search for entirely new ways of treatment. Oncolytic viruses are able to selectively induce the death of tumor cells without affecting normal cells. A murine Sendai virus has potential to be used as an oncolytic agent. However, tumors vary in their sensitivity to different viruses, prompting us to attempt to identify corresponding biomarkers that reflect the interaction of cancer cells and the virus. Here, we show that the sensitivity of primary prostatic adenocarcinoma cell lines to Sendai virus strain (SeVM) vary substantially. Using quantitative PCR, we evaluated expression levels of genes that encode RIG-1-like and Toll-like receptors (TLRs) in cell lines and showed that the levels of mRNAs that encode TLR3 and TLR7 correlate with a degree of sensitivity of the cells to Sendai virus. The lines with lower levels of TLR3 and TLR7 expression are more sensitive to the virus.

[The role of microRNA in abiotic stress response in plants].

Regulation of gene expression via microRNA is the key mechanism of response to biotic and abiotic stresses in plants. There are a lot of experimental data on the biological function of microRNAs in response to different stresses in various plant species. This review contains up-to-date information on molecular mechanisms of microRNA action in plants in response to abiotic stresses, including drought, salinity, mineral nutrient deficiency or imbalance.

[Molecular genetic mechanisms of drug resistance in prostate cancer].

The major problem in prostate cancer treatment is the development of drug resistance and especially important, cross-resistance. The mechanisms of drug resistance, which are divided into ligand-dependent (requiring the presence of androgens in the cell) and independent (not requiring the presence of androgens) are reviewed. The mechanisms are mainly represented with mutations of the androgen receptor and expression of aberrant constitutively active splice variants, as well as up-regulation of genes involved in androgens synthesis.

[Downregulation of OGDHL expression is associated with promoter hypermethylation in colorectal cancer].

Cell metabolic reprogramming is one of the cancer hallmarks. Glycolysis activation, along with suppression of oxidative phosphorylation and, to a lower extent, the TCA cycle, occurs in the majority of malignant tumors. A bioinformatics search for the glucose metabolism genes that are differentially expressed in colorectal cancer (CC) was performed using the data of The Cancer Genome Atlas (TCGA) Project. OGDHL for an oxoglutarate dehydrogenase complex subunit, which is involved in the TCA cycle and is indirectly responsible for the induction of apoptosis, was identified as one of the most promising candidates. A quantitative PCR analysis showed, on average, an eightfold downregulation of OGDHL in 50% (15/30) of CC samples. Based on the TCGA data, promoter hypermethylation was assumed to be a major mechanism of OGDHL inactivation. Bisulfite sequencing identified the OGDHL promoter region (+327 ... +767 relative to the transcription start site) that is often methylated in CC samples with downregulated ODGHL expression (80%, 8/10) and is possibly crucial for gene inactivation. Thus, frequent and significant OGDHL downregulation due to hypermethylation of a specific promoter region was demonstrated for CC. The OGDHL promoter methylation pattern was assumed to provide a marker for differential diagnosis of CIMP+ (CpG island methylator phenotype) tumors, which display dense hypermethylation of the promoter region in many genes.

[Evaluation of Gene Expression of Hexokinases in Colorectal Cancer with the Use of Bioinformatics Methods].

One of the hallmarks of cancer is the change of energy metabolism, mainly activation of glycolysis that occurs even at early stages of tumorigenesis. The glycolysis activation can be caused by overexpression of hexokinases, primarily HK1 and HK2. Colorectal cancer, which takes the third place in the cancer morbidity and mortality rates worldwide, is believed to be accompanied with overexpression of HK2, which is .considered a marker of poor prognosis. With the use of the developed CrossHub tool, we performed the analysis of the Cancer Genome Atlas RNA-Sequencing data, which, on the contrary, revealed the prevalence of the down-regulation of HK2 gene and only slight expression alterations in HK1 gene. The Cancer Genome Atlas is the largest resource in the field of molecular oncology that accumulated genomic, transcriptomic and methylomic data for thousands of sample of more than 20 cancers. The transcriptome analysis data for colorectal cancer (283 tumor samples and 41 matched normal samples) were in accord with the results of further qPCR expression level evaluation. Up-regulation of HK1 and HK2 genes was observed only in a part of samples: 12% for HK1 and 30% for HK2. At the same time, the HK2 mRNA level decrease was shown in 50% of cases. Correlation analysis revealed the consistency in HK1 and HK2 expression alterations (Spearman's rank correlation coefficient r(s) = 0.43, p < 0.01), that could be explained by common deregulation mechanisms of these genes in colorectal tumors. The HK3 expression level was significantly increased in 60% of samples. Most likely, just hexokinase 3 contributes significantly to the activation of glycolysis in colorectal cancer.

[Problem of the choice of the probiotic dose in the physician practice].

Currently, there is ample evidence of the usefulness of probiotics for human health, but, despite this, progress in the scientific and medical recognition of the legal force (legalization) of probiotic agents remains extremely slow. Probiotic preparations are prescribed with the preventive and medical purpose, must be not only safe, but always effective, because these properties affect the economic component of medical activity. Clinical efficacy of probiotics is determined not only by the specifics of strains, but also the adequacy of daily and course dose that should not be underestimated. Recent studies prove the identity of the impacts on human health probiotic agents and functional food products containing probiotic strains in optimal concentrations. Definition of preventive and curative doses of probiotics in children in different age periods remains a challenge for pediatricians.

[Dynamics of contamination and persistence of Clostridium difficile in intestinal microbiota in newborn infants during antibiotic therapy and use of probiotic strain enterococcus faecium L3].

Ninety four infants were observed as inpatients. Thirty nine of them were mature neonates and 55 were premature infants with a very low body weight. The majority of the patients were treated with antibiotics. The mature infants were treated with penicillins, aminoglycosides, cephalosporins and the premature neonates were treated in addition with carbapenems, fluoroquinolones, glycopeptides. The mature infants were randomized into 2 groups: the control group (n=18) received the standard therapy and the main group (n=21) in addition received 1 ml of liquid probiotic Enterococcus faecium L3 (with a titer of 5x10(8) CFU/ml) 2 times a day for 10 days. The premature newborn infants were also randomized into 2 groups. The control group (n=26) received the standard therapy. The main group (n=29) additionally received 1 ml of liquid probiotic E.faecium L3 2 times a day for 10 days. The effectiveness of the therapy in the mature neonates was evaluated by the frequency of dyspeptic disorders and in the premature infants by the frequency of infectious complications and the episodes of food intolerance. The intestinal microbiota of the infants was investigated by the real-time PCR and bacteriological analyses of the feces: in the mature infants on admission to the hospital and 10 days after the treatment (periods 1-2), in the premature infants on admission to the hospital and then twice with an interval of 14 days (periods 1-2-3). It was shown that the use of the probiotic strain E.faecium L3 during the antibiotic therapy in the premature infants promoted significant reduction in the frequency of infectious complications. In the mature neonates the probiotic therapy reduced the risk of dyspeptic disorder. The studies showed reduction in persistence of Clostridium difficile in the intestinal microbiota of the newborn infants receiving the antibiotic therapy in combination with probiotic E.faecium L3, that was accompanied by preserving and growth of bifidobacteria and lactobacilli and reduction of the number of opportunistic microorganisms.

Reversible zinc-induced injuries to erythrocyte membrane nanostructure.

Zinc-induced injuries to red blood cell membrane nanostructures at different zinc concentrations were studied by atomic force microscopy. In order to distinguish the intrinsic characteristics of membrane nanostructures, the membrane surfaces were represented by three orders using 3D Fourier transform. Increasing the concentrations of zinc ions modified the pattern of induced injuries: their depths and diameters and their number on the membrane surface test area increased. The injuries and their distribution for each order of membrane surface were analyzed. Albumin restored membrane nanosurface.