MiR-204-5p overexpression abrogates Dacarbazine-induced senescence in melanoma cells in vivo.

Cancer cell drug resistance hinders significantly therapeutic modalities in oncology. Dacarbazine is chemotherapeutic agent traditionally used for melanoma treatment although it's effectiveness insufficient. In the present study we performed NGS-based transcriptomic profiling of B16 melanoma tumors after Dacarbazine treatment in vivo.

[Vasculogenic mimicry].

Anti-angiogenic drugs are used as an established approach of malignant neoplasms therapy. It has been established that the development of the phenomenon of vasculogenic mimicry - a specific variant of tumor neoangiogenesis, which is formed in highly aggressive solid tumors, is associated with a decrease in the effectiveness of antitumor therapy. This review highlights the mechanisms of development of vasculogenic mimicry in malignant neoplasms, which is one of the alternative options for tumor blood supply.

Novel somatic Missense Mutations in Exon 11 of the KIT Gene are Detected in Melanoma.

Objective: The aim of the present study was to analyze mutations of the mast/stem cell growth factor receptor Kit (KIT) gene in patients with melanoma from Eastern Siberia regions of the Russian Federation.

Methods: KIT gene mutations in exons 11 and 13 were analyzed by Sanger sequencing in 57 tumor samples obtained from patients with KIT-positive melanomas localized in preferable locations.

Result: Mutations were identified in 21% of patients.

miR 204-5p inhibits apoptosis in dacarbazine-treated melanoma cells.

Melanoma is one of the most aggressive types of malignant tumors, commonly affecting young individuals. The treatment of metastatic tumors remains obscure due to the resistance of tumor cells to drugs mediated by various mechanisms. The acquisition of a resistant phenotype is associated with both genetic and epigenetic alterations in cancer cells.

Effects of Obesity and Calorie Restriction on Cancer Development.

The risk of malignant tumor development is increasing in the world. Obesity is an established risk factor for various malignancies. There are many metabolic alterations associated with obesity which promote cancerogenesis.

Focal adhesion alterations in G0-positive melanoma cells.

Background: Melanoma is a highly heterogeneous malignant tumor that exhibits various forms of drug resistance. Recently, reversal transition of cancer cells to the G phase of the cell cycle under the influence of therapeutic drugs has been identified as an event associated with tumor dissemination. In the present study, we investigated the ability of chemotherapeutic agent dacarbazine to induce a transition of melanoma cells to the G phase as a mechanism of chemoresistance.

miR-204-5p in vivo inhibition cause diminished CD45RO cells rate in lungs of melanoma B16-bearing mice.

The treatment of melanoma remains a challenge, despite novel approaches recently becoming available for disseminated tumors. RNA targeting is being intensively studied in various types of disease. The aim of the present study was to explore whether the in vivo use of a microRNA (miR)-204-5p inhibitor affected melanoma progression, and whether its metastasis affects target organ remodeling.

Transcriptomic Profiling Revealed Plexin A2 Downregulation With Migration and Invasion Alteration in Dacarbazine-Treated Primary Melanoma Cells.

Melanoma is highly heterogeneous type of malignant neoplasm that is responsible for the majority of deaths among other types of skin cancer. In the present study, we screened a list of differentially expressed genes in two primary, drug-naïve melanoma cell lines derived from patients with melanoma following treatment of the cells with the chemotherapeutic agent dacarbazine. The aim was to determine the transcriptomic profiles and associated alterations in the cell phenotype.

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MicroRNAs epigenetically regulate physiological and pathological processes. Previously, we found that miR-204-5p is expressed at low levels in melanoma cells, and an increase in its level leads to a change in proliferation, migration, and invasion of these cancer cells. Now, using bioinformatics analysis, it has been shown that the target of miR-204-5p is FOXC1 transcription factor, which is implicated in carcinogenesis.

[The significance of C-KIT gene mutations in the diagnosis and prognosis of malignant tumors].

Mutations in the gene encoding type III receptor tyrosine kinase that regulates cellular processes, such as differentiation, survival, proliferation, migration, and apoptosis, are found in some neoplasms: gastrointestinal stromal tumor, mastocytosis, melanoma, breast carcinomas, myeloid leukemias, and a number of others. Tumors that exhibit these mutations are sensitive to therapy with tyrosine kinase inhibitors, which makes it necessary to correctly identify the mutation status by in order to apply a personalized approach to therapy. This literature review shows that the type and localization of the gene mutation are of crucial prognostic value and significance in choosing drugs for antitumor therapy, but traditional diagnostic methods fail to determine accurate mutation characteristics.

miR-155 overexpression is followed by downregulation of its target gene, NFE2L2, and altered pattern of VEGFA expression in the liver of melanoma B16-bearing mice at the premetastatic stage.

MicroRNAs are involved in the control of tumour progression and in metastatic cascade dynamics. However, the role of microRNAs in distant organ reorganization at the premetastatic stage is less clear, although the process of premetastatic niche formation is a crucial event according to modern concepts of tumour dissemination. The role of the present study was to investigate the expression levels of miR-155, miR-21, miR-205 and miR-let7b, as well as that of their target genes, in target organs of melanoma metastasis at the premetastatic stage.

MicroRNAs' control of cancer cell dormancy.

'Dormancy', in the context of carcinogenesis, is a biological phenomenon of decreased cancer cell proliferation and metabolism. In view of their ability to remain quiescent, cancer cells are able to avoid cell death induced by chemotherapeutic agents, and thereby give rise to tumor relapse at a later stage. Being a dynamic event, the dormant state is controlled by several epigenetic mechanisms, including the action of microRNAs.

Semaphorin-5A downregulation is associated with enhanced migration and invasion of BRAF-positive melanoma cells under vemurafenib treatment in melanomas with heterogeneous BRAF status.

Tumor heterogeneity affects the efficacy of anticancer treatment as tumor subclones with distinct molecular patterns may be present within one tumor, leading to differing sensitivities to chemotherapeutic agents. In the present study, six melanoma tissue fragments were obtained from different parts of tumor of four patients and then the effect of vemurafenib treatment on biological characteristics and molecular processes of cell cultures was estimated by using MTT-test, apoptosis, migration and invasion assays, PCR real time. There was different BRAF status determined between cells derived from the central and peripheral regions of primary melanoma tumors.

Differences in microRNA expression between melanoma and healthy adjacent skin.

Background: The tumor microenvironment is composed of cancer-associated fibroblasts, tumor-associated macrophages, endothelial cells, immune cells, signaling molecules and extracellular matrix structures, which closelycommunicate with the tumor via multiple mechanisms. MicroRNAs are paracrine regulators that provide a direct interaction between the microenvironment and cancer cells. In the presentstudy, we aimed to identify the microRNA expression profile in melanoma compared with thatin healthy adjacent skin, with a further assessment of altered microRNA signaling pathways and target genes.

miR-204-5p and miR-3065-5p exert antitumor effects on melanoma cells.

MicroRNA (miR)-204-5p was previously identified to be downregulated in melanoma compared with melanocytic nevi. This observation prompted a functional study on miR-204-5p and the newly-identified miR-3065-5p, two miRNAs suggested to be tumor-suppressive oncomiRs. Application of miR-204-5p mimics or inhibitors resulted in a decrease or increase, respectively, in melanoma cell proliferation and colony formation.

Melanoma Screening Day in Krasnoyarsk Krai of the Russian Federation: Results from 2015-2016.

Objective: The Melanoma Screening Day Campaign started in the Russian Federation in 2006. In the present study, we analyzed the 2015-2016 survey questionnaire data acquired from screened individuals in the city of Krasnoyarsk in eastern Siberia, which has a population of one million, in order to understand the level of awareness regarding melanoma/ skin cancer prevention and early diagnosis. Methods: Individuals were enrolled in the screening campaign by mass media advertising.

MicroRNA in skin diseases.

MicroRNAs are essential regulators of various cellular processes such as cell growth, differentiation, apoptosis, and the immune response, acting as factors for translational repression and/or degradation of target messenger RNA. Currently, microRNAs are considered as promising biomarkers and therapeutic targets for different pathological conditions. Skin may serve as a convenient model for microRNA modulation studies due to the comparatively easy access to targets cells.

Antiproliferative and Pro-Apoptotic Effects of MiR-4286 Inhibition in Melanoma Cells.

Introduction: MicroRNAs are essential regulators of gene expression at the post-transcriptional level. Their expression is altered in cancer tissues, and evaluation of these alterations is considered a promising tool used to diagnose and identify prognostic markers.

Materials And Methods: The microRNA expression profiles of formalin-fixed, paraffin-embedded melanoma and melanocytic nevi samples were estimated with a microarray and subsequently validated by real-time PCR.

Genetic analysis of melanocortin 1 receptor red hair color variants in a Russian population of Eastern Siberia.

The melanocortin 1 receptor is a Gs protein-coupled receptor implicated in melanogenesis regulation. The receptor gene is highly polymorphic, which accounts for the association of several of its single-nucleotide polymorphisms (SNPs) with an increased risk of melanoma. The present study aimed to evaluate the distribution of melanocortin 1 receptor gene variants R151C, R160W, and D294H within the Russian population of Eastern Siberia and its association with melanoma development.

MICRORNAS AS ULTRAVIOLET IRRADIATION EFFECTS REGULATORS IN SKIN CELLS.

MicroRNAs belong to small non-coding RNA which regulate gene expression via mRNA degradation or translation inhibition. MicroRNAs are active modulators of gene expression in the skin caused by exogenous factors including ultraviolet irradiation. These effects are realized by targeting transcription factors and signaling systems components.

PROONCOGENIC EFFECTS OF INHIBITING THE microRNA miR-106A IN SKIN MELANOMA CELLS IN VITRO.

One of the regulators of gene expression at the post-transcriptional level are miRNAs. Due to its multifunctionality, these molecules are considered as potential targets for controlling the biological behavior of tumor cells. To date, several thousand types of microRNAs have been identified and their expression profiles have shown significant during malignant transformation of cells.

[ Bioluminescent assay to detect melanocortin-1 receptor (MC1R) polymorphisms (R160W, R151C, and D294H)].

Several polymorphisms in melanocortin-1 receptor (MC1R) gene are shown to have associations with melanoma risk. In particular, rs1805007, rs1805008, and rs1805009 mutations causing the corresponding R151C, R160W, and D294H changes and associated with the phenotype ("red-hair mutations") are connected with melanoma and non-melanoma skin cancer risks. The work describes the approach to detect these polymorphisms based on primer extension reaction with the following dual bioluminescent assay.

[Molecular and pathomorphological prognostic markers for melanoma: Current approaches and prospects].

The incidence of melanoma demonstrates a persistent increasing tendency, which justifies the need to study and identify new prognostic markers for the development and course of this disease. The given paper shows current approaches to melanoma staging, including those to applying pathomorphological prognostic criteria, and discusses prospects for using the results of genomic and epigenomic studies of the carcinoma in clinical practice.