Vol 51, No 1 (2017)

Bronchial asthma is a chronic inflammatory disease of the airways that is characterized by episodes of shortness of breath, expiratory dyspnea, cough, wheezing, and pulmonary emphysema. At the present time, asthma is a global public health problem and affects about 5% of the worldwide population. Although a wide range of anti-inflammatory drugs is available, uncontrolled or poorly controlled asthma is still a problem, requiring the development of novel therapeutic approaches. Intense studies of the molecular mechanisms of asthma in transgenic animals performed since the 1990s implicated cytokines, such as IL-4, IL-5, and IL-13, and their receptors in the initiation and maintenance of asthma. These findings led to anticytokine therapy as a novel approach for bronchial asthma treatment. To date, many preclinical and clinical studies have been performed in this field especially with drugs based on humanized monoclonal antibodies, soluble receptors, peptide inhibitors, etc. The review summarizes the data from preclinical and clinical studies of anti-cytokine therapeutics in humans.

Glaucoma is a heterogeneous eye disease characterized by optic nerve atrophy and visual field defects. The disease damages the retinal ganglion cells (RGC) and their functional axons. Heat shock proteins 70 (HSP70) are molecular chaperons that could have a protective effect in the development of glaucoma. Polymorphisms of HSP70 may alter protein function or expression and are associated with the susceptibility to glaucoma. The purpose of this study was to investigate whether the HSPA1B 1267A/G (rs1061581) and HSPA1L 2437T/C (rs2227956) variants contribute to glaucoma susceptibility. Genomic DNA samples from 169 patients with glaucoma and 178 healthy controls were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Here we show that the presence of HSPA1B 1267GG genotype significantly increases the risk of glaucoma (OR = 3.16, 95% CI = 1.45–6.89, p = 0.003). The prevalence of HSPA1L 2437T/C genotypes in patients and controls did not differ significantly (p = 0.31, χ² = 2.32). However, large population based studies are required for further evaluation and confirmation of our finding.

A comparative analysis of oncogene mutations shows that variations in their frequency, spectrum, and hot-spot locations depends on the type of tumor and the ethnic origin of the population studied. The current version of the IARC TP53 Mutation Database lacks information about the frequency and spectrum of TP53 mutations in patients with DLBCL in Russia. The aim of this study was to assess the frequency and functional significance of TP53 mutations in patients with DLBCL in Novosibirsk. The TP53 coding sequence and the adjacent intron regions were analyzed by direct sequencing in the tumor material from 74 patients with DLBCL. Mutations of the TP53 coding sequence were found in 18 (24.3%) patients. These data are consistent with the frequency of TP53 mutations observed in other studies. The spectrum of nucleotide substitutions found in DLBCL specimens corresponded to that described in the IARC TP53 Mutation Database. According to bioinformatic data and to reported experiments in vitro, most of the mutations detected result in the production of functionally inactive p53. Our results show that DLBCL progression is accompanied by the functional selection for mutations in TP53 exons 5–8.

In vertebrates, evolutionarily conserved signaling intermediate in the Toll pathway (ECSIT) interacts with the TNF-receptor associated factor 6 (TRAF6) to regulate the processing of MEKK1, activate NF-κB, and also control BMP target genes. However, the role of ECSIT in invertebrates remains largely unexplored. We performed comparative investigations of the expression, gene structure, and phylogeny of ECSIT, Tolllike receptor (TLR), and Smad4 in the cephalochordate Branchiostoma belcheri. Phylogenetic analysis indicated that, in amphioxus, ECSIT, TLR, and Smad4 form independent clusters at the base of Chordate clusters. Interestingly, overall gene structures were comparable to those in vertebrate orthologs. Transcripts of AmphiECSIT were detectable at the mid-neural stage, and continued to be expressed in the epithelium of the pharyngeal region at later stages. In adult animals, strong expression was observed in the nerve cord, endostyle, epithelial cells of the gut and wheel organ, genital membrane of the testis, and coelom and lymphoid cavities, what is highly similar to AmphiTLR and AmphiSmad4 expression patterns during development and in adult organisms. Our data suggests that ECSIT is evolutionarily conserved. Its amphioxus ortholog functions during embryonic development and as part of the innate immune system and may be involved in TLR/BMP signaling.

Methylation of promoter CpG islands and microRNA (miRNA) interactions with mRNAs of target genes are epigenetic mechanisms that play a crucial role in deregulation of gene expression and signaling pathways in tumors. Altered expression of six chromosome 3p genes (RARB(2), SEMA3B, RHOA, GPX1, NKIRAS1, and CHL1) and two miRNA genes (MIR-129-2 and MIR-9-1) was observed in primary clear cell renal cell carcinomas (ccRCCs, 31–48 samples) by RT-PCR and qPCR. Significant downregulation (p < 0.05, Fisher’s exact test) was observed for SEMA3B, NKIRAS1, and CHL1; and differential expression, for the other chromosome 3p and miRNA genes. Methylation-specific PCR with primers to RARB(2), SEMA3B, MIR-129-2, and MIR-9-1 showed that their methylation frequency was significantly (p < 0.05, Fisher’s exact test) elevated in the ccRCC samples. Significant correlations between promoter methylation and expression were confirmed for SEMA3B and observed for the first time for RARB(2), GPX1, and MIR-129-2 in ccRCC (Spearman’s correlation coefficient r_s ranging 0.31–0.60, p < 0.05). The MIR-129-2 and RARB(2) methylation frequencies significantly correlated with ccRCC progression. MIR-129-2 methylation correlated with upregulation of RARB(2), RHOA, NKIRAS1, and CHL1 (r_s ranging 0.35–0.53, p < 0.05). The findings implicate methylation in regulating RARB(2), SEMA3B, GPX1, and MIR-129-2 and indicate that miR-129-2 and methylation of its gene affect RARB(2), RHOA, NKIRAS1, and CHL1 expression.

The experimental study identified the antiviral activity of Bacillus pumilus RNase (binase) against the reovirus of serotype 1/strain Lang. For the first time, it has been found that 50 μg/mL of binase effectively reduced the hemagglutinin and cytocidal activity of reovirus in Vero cell line. The preincubation of the enzyme with reovirus before infection of the cells inhibited the viral replication. To determine the stagedependent effect of reovirus reproduction upon binase inhibition, the infected cells were treated with binase or RNase A at different phases of the infectious cycle. The treatment of virus-infected cells has revealed that both enzymes have a maximal antiviral effect on the reovirus propagation during early phases of the reovirus reproduction cycle, with binase being more effective than RNase A. It has been hypothesized that the combined action of the oncolytic reovirus and binase is promising for the elimination of tumor cells carrying mutated RAS gene.

Serotonin receptors 5-HT_1A and 5-HT₇ are involved in the development of various psychopathologies. Some data indicate that there is an interplay between 5-HT_1A 5-HT₇ receptors that could be implicated in the regulation of their function. This work analyzed the effects of chronic 5-HT₇ activation on the functional activity of 5-HT₇ and 5-HT_1A receptors, on the corresponding protein levels, and on the expression of genes encoding 5-HT₇ and 5-HT_1A receptors in the mouse brain. Chronic administration of the 5-HT₇ selective agonist LP44 (20.5 nmol, i.c.v., 14 days) produced considerable desensitization of both 5-HT₇ and 5-HT_1A receptors. In LP44-treated mice, the hypothermic responses mediated by both 5-HT₇ and 5-HT_1A receptors were attenuated. Moreover, the levels of 5-HT_1A receptor protein in the midbrain and the frontal cortex of LP44-treated mice were significantly decreased. However, the brain levels of 5-HT₇ receptor protein did not differ between LP44-treated and control mice. Chronic LP44 treatment did not alter the expression of the 5-HT₇ and 5-HT_1A receptor genes in all investigated brain structure. These data suggest that 5-HT₇ receptors participate in the posttranscriptional regulation of the 5-HT_1A receptors functioning.

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 efficiency of the antitumor immune response triggered by dendritic cell (DC)-based vaccines depends predominantly on the efficiency of delivering tumor antigen-coding nucleic acids into DCs. Mannosylated liposomes were used to deliver tumor total RNA into DCs both ex vivo and in vivo, and the cytotoxic T-lymphocyte (CTL) antitumor response was assayed. The liposomes contained the mannosylated lipid conjugate 3-[6-(α-D-mannopyranosyloxy)hexyl]amino-4-{6-[rac-2,3-di(tetradecyloxy)prop-1-yl oxycarbonylamino]hexyl}aminocyclobut-3-en-1,2-dione), the polycationic lipid 2X3 (1,26-bis(cholest-5-en-3β-yloxycarbonylamino)-7,11,16,20-tetraazahexacosane tetrahydrochloride), and the zwitterionic lipid DOPE (1,2-dioleoyl-sn-glycero-3-phosphoethanolamine) at a molar ratio of 1: 3: 6 and were used as a transfection agent. Total RNA isolated from B16-F10 mouse melanoma cells served as a source of tumor antigens. Systemic administration of mannosylated liposomes–tumor RNA complexes into circulation of melanoma- bearing mice induced an efficient CTL response, which reduced the melanoma cell index in vitro with the same efficiency (by a factor of 2.8) as CTLs activated via an inoculation of DCs loaded with complexes of the same composition ex vivo. Complexes of tumor RNA with control liposomes, which lacked the mannosylated lipid conjugate, or DCs transfected with these complexes ex vivo were less efficient and reduced the melanoma cell count by a factor of only 1.6–1.8.

In both prokaryotes and eukaryotes, the survival at temperatures considerably exceeding the optimum is supported by intense synthesis of the so-called heat shock proteins (HSPs), which act to overcome the adverse effects of heat stress. Among mycoplasmas (class Mollicutes), which have significantly reduced genomes, only some members of the Acholeplasmataceae family possess small HSPs of the α-crystallin type. Overproduction of a recombinant HSP IbpA (Hsp20) from the free-living mycoplasma Acholeplasma laidlawii was shown to increase the resistance of Escherichia coli to short-term heat shock. It has been long assumed that IbpA prevents protein aggregation and precipitation thereby increasing viability of E. coli cells. Several potential target proteins interacting with IbpA under heat stress were identified, including biosynthetic enzymes, enzymes of energy metabolism, and components of the protein synthesis machinery. Statistical analysis of physicochemical properties indicated that IbpA interaction partners significantly differ in molecular weight, charge, and isoelectric point from other members of the E. coli proteome. Upon shortterm exposure to increased temperature, IbpA was found to preferentially interact with high-molecularweight proteins having a pI of about 5.1, significantly lower than the typical values of E. coli proteins.

Na,K-ATPase maintains sodium and potassium homeostasis. It is the only known receptor for cardiotonic steroids such as ouabain. Binding of ouabain to Na,K-ATPase leads to the activation of Src kinase and the subsequent initiation of intracellular signaling pathways, including the induction of apoptosis. Changes in Na,K-ATPase activity is one of the earliest responses to hypoxia and is most critical for cell survival. However, it is not known how the hypoxia affects the functioning of Na,K-ATPase as a receptor. We have shown that, under the conditions of hypoxia and ischemia, ouabain is less toxic for murine fibroblast cells (SC-1 cell line) and ouabain does not cause an increase in the level of reactive oxygen species, which is typically observed at 20% pO₂. Under hypoxia, the treatment of cells with ouabain also does not lead to the activation of Na,K-ATPase-associated Src kinase. Thus, at low oxygen content, the receptor function of Na,K-ATPase is altered, and cells become less sensitive to cardiotonic steroids. The decrease in sensitivity to cardiotonic steroids, which is evident at hypoxic conditions, should be taken into account in clinical practice. At the same time, in the presence of ouabain the cells are less sensitive to hypoxia, which indicates that cardiotonic steroids can be protective in acute ischemia.

Dikkoppf-1 (DKK1) is an antagonist of the canonical Wnt signaling pathway. The importance of DKK1 as a diagnostic and therapeutic agent in a wide range of diseases along with its significance in a variety of biological processes accentuate the necessity to decipher its 3D structure that would pave the way towards the development of relevant selective inhibitors. A DKK1 structure model predicted by the Robetta server with structural refinements including a 10 ns molecular dynamics run was subjected to functional and docking analyses. We hypothesize that the N-terminal region of the DKK1 molecule could be functionally important for both canonical and noncanonical Wnt pathways. Moreover, it seems that DKK1 could be involved in interactions with the Frizzled receptors, leading to the activation of the Planar Cell Polarity (PCP) pathway (activation of Jun N-terminal kinase (JNK) Pathway) and Wnt/Ca²⁺ pathway (activation of CamKII).