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.
View Article and Find Full Text PDFBackground: 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.
View Article and Find Full Text PDFMicroRNA (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.
View Article and Find Full Text PDFMicroRNAs 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.
View Article and Find Full Text PDFIntroduction: 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.
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.
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