Uveal melanoma (UM) is a neuroectodermal tumor that results from malignant transformation of melanocytes in the eye uvea, including the iris, the ciliary body, and the choroid. UM accounts for 5% of all melanoma cases and is extremely aggressive with half of the UM patients developing metastases within the first 1-2 years after tumor development. Molecular mechanisms of UM carcinogenesis are poorly understood, but are known to differ from those of skin melanoma. Activating mutations of the GNAQ and GNA11 genes, which code for the large G protein subunits Gq and G11, respectively, are found in 90% of UM patients. The Gaq/PKC/MAPK signaling pathway is a main signaling cascade that leads to the transformation of melanocytes of the uveal tract, and major regulators of the cascade provide targets for the development of drugs. Metastatic UM (MUM) is most often associated with mutations of BAP1, EIF1AX, GNA11, GNAQ, and SF3B1. A combination of a commercial expression test panel of 15 genes and a mutation panel of 7 genes, supplemented with data on the size of the primary tumor, is highly efficient in predicting the risk of metastasis. The risk of metastasis determines the choice of therapy and the patient follow-up regimen. However, no systemic therapy for MUM has been developed to date. New drugs undergoing clinical trials are mostly targeted drugs designed to inhibit the protein products of mutant genes or immunotherapeutic agents designed to stimulate the immune response against specific antigens. In addition to these approaches, potential therapeutic targets of epigenetic regulation of UM development are considered in the review.

Screening for new antibiotics remains an important area of biology and medical science. Indispensable for this type of research is early identification of antibiotic mechanism of action. Preferentially, it should be studied quickly and cost-effectively, on the stage of primary screening. In this review we describe an application of reporter strains for rapid classification of antibiotics by its target, without prior purification of an active compound and determination of chemical structure.

Externally, vertebrates are bilaterally symmetrical; however, left-right asymmetry is observed in the structure of their internal organs and systems of organs (circulatory, digestive, and respiratory). In addition to the asymmetry of internal organs (visceral), there is also functional (i.e., asymmetrical functioning of organs on the left and right sides of the body) and behavioral asymmetry. The question of a possible association between different types of asymmetry is still open. The study of the mechanisms of such association, in addition to the fundamental interest, has important applications for biomedicine, primarily for the understanding of the brain functioning in health and disease and for the development of methods of treatment of certain mental diseases, such as schizophrenia and autism, for which the disturbance of left-right asymmetry of the brain was shown. To study the deep association between different types of asymmetry, it is necessary to obtain adequate animal models (primarily animals with inverted visceral organs, situs inversus totalis). There are two main possible approaches to obtaining such model organisms: mutagenesis followed by selection of mutant strains with mutations in the genes that affect the formation of the left-right visceral asymmetry and experimental obtaining of animals with inverted internal organs. This review focuses on the second approach. We describe the theoretical models for establishing left-right asymmetry and possible experimental approaches to obtaining animals with inverted internal organs.

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.

All three types of peroxisome proliferation activating rexeptiors (PPAR): α, β/δ and γ, are sensors of fat acids and their derivatives and carry out the transcription adjusting of genes of exchange of lipids, including circulation of cholesterol and sensitiveness of tissues to insulin. They possess antiinflammatory properties, control activity of cells of the immune system, endothelia and smooth musculature of vessels. Such combination of functions does PPAR an ideal target for a prophylaxis and treatment of atherosclerosis. Nevertheless, 20-years-old experience of the use of tiazolidinodiones--agonists of PPARγ, as antidiabetic facilities, did not bring to the decline of morbidity and death rate of patients with diabetes mellitus 2 types from cardiovascular complication. The only exception is pioglitazone, which significantly reduces the mortality rate of patients with T2DM remains effective in the prevention and treatment of atherosclerosis. Effective not enough in this plan and fibrates--agonists of PPARa. Possible reasons of it and nearest perspestives are examined in a review.

Some ribonucleases (RNases) produce selective toxic effect on the cancer cells. The mechanism of this antitumor activity remains largely unclear. The subject of this review is the RNases interaction with cellular components, resulting in the induction of apoptosis of tumor cells. Cell surface structures, which are potential acceptors of the exogenous RNase are discussed: acidic lipids and glycoproteins, heparansulfate-containing proteoglycans, actin, and RNA-associated proteins. Cell membranes of normal and malignant cells differ according to the composition of these components, which largely determines the selectivity of RNases for the latter. Different types of RNA are examined as intracellular targets of the RNases activity, evidence is presented demonstrating the possibility of exogenous RNases intervening in the process of RNA interference. The role of potassium channels, NF-kappaB-dependent.signaling pathway and various caspases in apoptosis induced by exogenous RNases is discussed. Evidence is also presented showing that the sensitivity of cells to exogenous RNases is linked to the expression of certain oncogenes, namely RAS, KIT, AML1-ETO. It is suggested that discovering the details of the mechanisms of RNases cytotoxic effect in malignant cells susceptible to their activity, will in the future serve as a foundation to developing new tools of targeted anticancer therapy.

At present, epigenetic regulation is considered as a dynamic mechanism by means of which cells realize adaptive response to signals from both the inner medium and environment. DNA methylation, as bidirectional balance of the activity of histone-acetylation and -deacetylation (HDAC) enzymes, determines the conformation of chromatin thus playing the main role in "appropriate" gene expression. HDACs represent emerging therapeutic targets in the context of treating various forms of neurological and mental illness. A wide range of brain diseases are associated with imbalance between protein acetylation levels and tran- scriptional dysfunctions. Increasing evidence supports the notion that histone hypoacetylation and transcriptional dysfunction are involved in a large number of neurodegenerative conditions in vivo and in vitro. Histone deacetylase inhibitors (HDACIs) that affect the acetylation status of histones and other important cellular proteins--have been recognized as potentially useful therapeutic means for a broad range of human disorders. This review summarizes the current state of development of HDACIs based therapeutics and their application for the treatment of human brain neurodegenerative, ischemic, and cognitive pathologies. Treatment with various HDACIs can correct these deficiencies and has emerged as a promising new strategy for therapeutic intervention based on the experimental search and clinical testing of HDACIs representing compounds of various classes.

The use of immunodepressants in the medical practice provided tens of thousands of favourable outcomes of the liver, kidney or heart transplantation and significant success in the treatment of a number of autoimmune diseases. Calcineurine inhibitors (cyclosporine A and tacrolimus) provoke a number of adverse reactions. Among them nephrotoxicity is clinically most dangerous. Complex estimation of the immunological and biochemical indices in the treatment with calcineurine inhibitors is an important precondition for increasing the efficacy of immunodepressive therapy and decreasing the frequency and level of the adverse reactions.

It was thought that antibiotics should be produced by soil microorganisms to inhibit the growth of competitors in natural habitats. Yet it has been shown that antibiotics at subinhibitory concentrations may have a role as signalling molecules providing cell-to-cell communication in bacteria in the environment. Antibiotics modulate gene transcription and regulate gene expression in microbial populations. Subinhibitory concentrations of antibiotics may cause a number of phenotypic and genotypic changes in microorganisms. These transcription changes are dependent on the interaction of antibiotics with macromolecular receptors such as ribosome or RNA-polymerase. Antibiotic signalling and quorum-sensing system are important regulatory mechanisms in bacteria. It was demonstrated that antibiotics interfered with quorum-sensing system.

Cytokines CCL11 (eotaxin) and HMGB1 (alarmin1) are molecular markers of ageing and neurological, cardiovascular and immune diseases. Created in St. Petersburg Institute of Bioregulation and Gerontology short peptides are known to regulate gene expression and protein synthesis. They promote the mortality decrease and slowdown the development of pathology in the elderly. The article presents the proposed role of dipeptide vilon (Lys-Glu) and tetrapeptide epitalon (Ala-Glu-Asp-Gly) in CCL11 and HMGB1 genes regulation as activators of their expression. Geroprotective action of vilon and epitalon probably realizes in suppression of these genes.

The mechanisms of participation of multidrug-resistance proteins (MRPs) in sex difference pattern of drug efficiency and side effects have been analyzed. MRPs structure, their tissue and cellular localization, substrate specificity, and functions have been considered. Regulation of expression and activity of MRPs by endogenous metabolites, signal compounds, including sex hormones, as well as by drug agents have been represented. The role of nuclear receptors in the regulation of MRPs expression has been demonstrated. The data on sex differences in hepatic and renal MRPs expression and expression of nuclear receptors, participating in their induction, have been shown. The participation of MRPs in the formation of sex differences of drug pharmacokinetics has been discussed. Sex differences in representation and functional activity of MRPs in such excretory organs as liver and kidney was concluded would play the essential role in sex dependence of pharmacokinetics and efficiency of drug action.

Mechanisms of anti-cancer effects of polyphenols, found in fruits, vegetables, spices and representing parts of daily nutrition, have been considered. These compounds may be the basis for development of cancer preventive preparations. They can block carcinogenesis initiation by inactivation of exogenous or endogenous genotoxic molecules including reactive oxygen species. Another mechanism consists in inhibition of activity and synthesis of carcinogen-metabolizing enzymes. Plant polyphenols also induce expression of antioxidant and detoxification enzymes genes.

Here we present a brief review of the reports concerning proteome modifications under the influence of salicylic acid, which is one of the major mediators of both local and systemic immunity. We describe also the results of our own studies of the salicylate-induced changes in proteomes of pea leaves and roots. Fifteen salicylate-inducible proteins, which were previously unknown, have been identified. Unlike the roots, leaves accumulated some chloroplast proteins and enzymes capable of degrading the pathogen cell walls. In the roots, salicylic acid increased the content of enzymes, improving the resistance of plant cells themselves, and promoted the disappearance of reductase of oxophytodienic acid. The latter could lead to inhibition of jasmonic acid synthesis and stimulation of local immunity. High (apoptotic) concentration of salicylic acid intensified synthesis of root proteins involved in the formation of heteroprotein complexes, which play an important role in the functioning of the signaling system, DNA synthesis and repair, and protein synthesis, refolding, and proteolysis.

Nuclear receptors are transcription factors that are essential in embryonic development, cellular differentiation, metabolism. Ligand-regulated nuclear PXR receptor responds to diverse arrays of chemically distinct ligands, xenobiotics, drugs and regulates expression of the genes involved in xenobiotic and drug metabolism. The structural basis of the receptor provides interaction with a variety of ligands which are agonists or antagonists. Nuclear receptors researches are important for design of metabolism regulating drugs and in drug interaction studies.

A putative way of the protective action of cytokinins on the photosynthetic processes in crops experiencing various stress factors is considered. Various cytokinins are characterized. Pathways of the multiple effects of cytokinin preparations mediating the protection of the photosynthetic machinery from stress are described. Cytokinins interact with receptor proteins, and then the signal is transduced to primary cellular targets (primary response genes). These genes, which possess receptor domains, induce synthesis of the corresponding mRNAs and photosynthesis-related proteins of chlorophyll-protein complexes, the electron-transport chain, and carbon metabolism, primarily, the key enzyme ribulose bisphosphate carboxylase/oxygenase. The protective action of cytokinins under stress conditions preserves the structure and function of the photosynthetic apparatus. The application of cytokinins to improving crop yields is discussed.

This review is devoted to genomic instability in the offspring of parents that were irradiated or treated with chemical mutagens. The evidence is presented, showing high frequency of cancer diseases and instability of the genome of somatic and germline cells in the offspring of radiation-exposed animals. Possible epigenetic mechanisms of these effects are considered, as well as their significance as components of genetic factors of radiation risk for humans.

Bacteria are capable to sense an increase of cell density population and to reply quickly and coordinately by the induction of special sets of genes. This type of the regulation was named Quorum Sensing (QS); it is based on the effect of low-molecular-weight signaling molecules of different nature (autoinducers) which accumulate in the culture at high density of bacterial population and interact with receptor regulatory proteins. QS systems are the global regulators of bacterial genes expression and play a key role in the control of many metabolic processes in cell including the regulation of virulence of bacteria. Here we review the molecular mechanisms of QS systems functioning in bacteria belonging to different taxonomic groups and discuss the potential of QS regulation as a new drug target for the treatment of bacterial infections. At present this approach is accounted as a new alternative strategy of antimicrobial therapy directed on the development of drugs inhibiting QS regulation and active just against pathogenicity of bacteria (antipathogenic drugs). Such a strategy allows to avoid a wide dissemination of resistant forms of pathogenic bacteria and the formation of biofilms increasing in many times the resistance of bacteria to drug preparations.

Exposure to high concentrations of environmental NaCl exerts two stress effects on living cells, increasing the osmotic pressure and the concentration of inorganic ions. Salt stress dramatically suppresses the photosynthetic activity in cells of phototrophic organisms, such as cyanobacteria. During salt adaptation, cyanobacterial cells accumulate osmoprotectors, export excessive Na+ with the help of Na+/H+ antiporters, and actively absorb K+ with the help of K+-transporting systems. These physiological processes are accompanied by induction or suppression of several genes involved in salt adaptation. The review considers the main mechanisms responsible for the resistance of cyanobacterial cells to salt and hyperosmotic stresses. Special emphasis is placed on recent achievements in studying the genetic control of salt resistance and regulation of gene expression during adaptation of cyanobacteria to salt and hyperosmotic stresses.

We considered the biological effects of some chemical compounds, that stimulate cell differentiation, on the cells of tumor lines. Induced changes were analyzed in the expression of several transcriptional factors involved in the regulation of cell proliferation and apoptosis. Based on the generalized information about differentiating, apoptogenic, and antiproliferative effects of chemical inducers of differentiation, a conclusion was drawn that they affect the sensitivity of differentiated cells to the lytic action of natural killer cells.