Тоневицкий Александр Григорьевич

Comprehensive network of miRNA-induced intergenic interactions and a biological role of its core in cancer

2018 · ARTICLE · en

MicroRNAs (miRNAs) are a family of short noncoding RNAs that posttranscriptionally regulate gene expression and play an important role in multiple cellular processes. A significant percentage of miRNAs are intragenic, which is often functionally related to their host genes playing either antagonistic or synergistic roles. In this study, we constructed and analyzed the entire network of intergenic interactions induced by intragenic miRNAs. We further focused on the core of this network, which was defined as a union of nontrivial strongly connected components, i.e., sets of nodes (genes) mutually connected via directed paths. Both the entire network and its core possessed statistically significant non-random properties. Specifically, genes forming the core had high expression levels and low expression variance. Furthermore, the network core did not split into separate components corresponding to individual signalling or metabolic pathways, but integrated genes involved in key cellular processes, including DNA replication, transcription, protein homeostasis and cell metabolism. We suggest that the network core, consisting of genes mutually regulated by their intragenic miRNAs, could coordinate adjacent pathways or homeostatic control circuits, serving as a horizontal inter-circuit link. Notably, expression patterns of these genes had an efficient prognostic potential for breast and colorectal cancer patients.

Knockdown of L1CAM significantly reduces metastasis in a xenograft model of human melanoma: L1CAM is a potential target for anti-melanoma therapy

2018 · ARTICLE · en

Finding additional functional targets for combination therapy could improve the outcome for melanoma patients. In a spontaneous metastasis xenograft model of human melanoma a shRNA mediated knockdown of L1CAM more than sevenfold reduced the number of lung metastases after the induction of subcutaneous tumors for two human melanoma cell lines (MeWo, MV3). Whole genome expression arrays of the initially L1CAM high MeWo subcutaneous tumors revealed unchanged or downregulated genes involved in epithelial to mesenchymal transition (EMT) except an upregulation of Jagged 1, indicating a compensatory change in Notch signaling especially as Jagged 1 expression showed an increase in MeWo L1CAM metastases and Jagged 1 was expressed in metastases of the initially L1CAM low MV3 cells as well. Expression of 17 genes showed concordant regulation for L1CAM knockdown tumors of both cell lines. The changes in gene expression indicated changes in the EMT network of the melanoma cells and an increase in p53/p21 and p38 activity contributing to the reduced metastatic potential of the L1CAM knockdowns. Taken together, these data make L1CAM a highly interesting therapeutic target to prevent further metastatic spread in melanoma patients.

Selectin-independent adhesion during ovarian cancer metastasis

2017 · ARTICLE · en

Purpose: Ovarian cancer (OvCa) progression mainly takes place by intraperitoneal spread. Adhesion of tumor cells to the mesothelial cells which form the inner surface of the peritoneum is a crucial step in this process. Cancer cells use in principle different molecules of the leukocyte adhesion cascade to facilitate adhesion. This cascade is initiated by selectin-ligand interactions followed by integrin - extracellular matrix protein interactions. Here we address the question whether all tumor cells pre- dominantly employ selectin-dependent leukocyte-like adhesion cascade (SDAC) or whether they use integrin mediated adhesion for OvCa progression as well. Methods: A comparative transcriptomic analysis of the human OvCa cell lines OVCAR8 and SKOV3 was performed. Intraperitoneal xenograft model of OVCAR8 cells was used to determine whether there is a correlation between SDAC gene expression and the metastatic potential of the control cells and the cells overexpressing c-Fos. Transcriptomic analysis of OVCAR8 and SKOV3 samples was performed using microarrays. Results: One-third of the protein-coding genes involved in SDAC exhibited lower expression levels in OVCAR8 than in SKOV3 cells. In contrast to SKOV3 cells, c-Fos overexpression in OVCAR8 cells did not significantly influence the expression of SDAC genes. Intraperitoneal xenograft model of OVCAR8 cells unexpectedly demonstrated that the aggressiveness of OVCAR8 tumors was not depended on the c-Fos expression level and was comparable to that of SKOV3 control tumors. Gene expression analysis of tu- mors suggests that SKOV3-derived tumor progression was mainly depended on SDAC. Progression of OVCAR8 tumors relied on other cell adhesion molecules that do not interact with selectins. Conclusions: High expression of c-Fos in ovarian cancer cells is not always associated with reduced metastatic potential. Low expression level of SDAC genes may not ensure low OvCa metastatic potential hence alternative adhesion mechanisms involving laminin-integrin interactions exist as well.

The Transcriptome of Type I Murine Astrocytes under Interferon-Gamma Exposure and Remyelination Stimulus

2017 · ARTICLE · en

Astrocytes are considered to be an important contributor to central nervous system (CNS) disorders, particularly multiple sclerosis. The transcriptome of these cells is greatly affected by cytokines released by lymphocytes, penetrating the blood–brain barrier—in particular, the classical pro-inflammatory cytokine interferon-gamma (IFNγ). We report here the transcriptomal profiling of astrocytes treated using IFNγ and benztropine, a putative remyelinization agent. Our findings indicate that the expression of genes involved in antigen processing and presentation in astrocytes are significantly upregulated upon IFNγ exposure, emphasizing the critical role of this cytokine in the redirection of immune response towards self-antigens. Data reported herein support previous observations that the IFNγ-induced JAK-STAT signaling pathway may be regarded as a valuable target for pharmaceutical interventions.

Receptor Mincle promotes skin allergies and is capable of recognizing cholesterol sulfate

2017 · ARTICLE · en

Sterile (noninfected) inflammation underlies the pathogenesis of many widespread diseases, such as allergies and autoimmune diseases. The evolutionarily conserved innate immune system is considered to play a key role in tissue injury recognition and the subsequent development of sterile inflammation; however, the underlying molecular mechanisms are not yet completely under- stood. Here, we show that cholesterol sulfate, a molecule present in relatively high concentrations in the epithelial layer of barrier tis- sues, is selectively recognized by Mincle (Clec4e), a C-type lectin re- ceptor of the innate immune system that is strongly up-regulated in response to skin damage. Mincle activation by cholesterol sulfate causes the secretion of a range of proinflammatory mediators, and s.c. injection of cholesterol sulfate results in a Mincle-mediated in- duction of a severe local inflammatory response. In addition, our study reveals a role of Mincle as a driving component in the path- ogenesis of allergic skin inflammation. In a well-established model of allergic contact dermatitis, the absence of Mincle leads to a sig- nificant suppression of the magnitude of the skin inflammatory re- sponse as assessed by changes in ear thickness, myeloid cell infiltration, and cytokine and chemokine secretion. Taken together, our results provide a deeper understanding of the fundamental mechanisms underlying sterile inflammation.

miRNA-mediated expression switch of cell adhesion genes driven by microcirculation in chip

2017 · ARTICLE · en

Panel of 6 microRNAs for minimally invasive diagnosis of prostate cancer

2017 · ARTICLE · en

INTRODUCTION AND OBJECTIVES: Routine screening of prostate cancer (PC) based on serum prostate-specific antigen detection and digital rectal examination has modest positive and negative predictive value. The aim of represented study was to identify a panel of plasma microRNAs (miRNAs) for minimally invasive diagnosis of PC. METHODS: During 2014-2015, 245 patients participated in the cross-sectional study. The Group 1 consisted of 188 patients with histologically confirmed PC. The Group 2 consisted of 57 patients including healthy individuals and patients with benign prostatic hyperplasia, urinary system diseases or anomalies, bladder or renal cancer. Plasma miRNAs profiles was studied with aid of GeneChip’ miRNA 4.0 Arrays (Affymetrix, USA) comprising probe set for 2,578 human mature miRNAs. All miRNAs with the 3rd quartile of Bi-weight Average Signal (log2) less than 1,49 were excluded from the analysis just as miRNAs with signal correlating with hemoglobin level as hemolysis sign (p-value RESULTS: Diagnostic significance was demonstrated even for pairs of miRNAs. In particular best pair consisting of hsa-miR155-5p and hsa-miR-619-5p allowed achieving 80.7% sensitivity at 69.2% specificity (AUC 0.817). Triplets of miRNAs showed better accuracy, e.g. for triplet hsa-miR-155-5p, hsa-miR-619-5p, and hsamiR-6777-5p sensitivity was 78.9% while specificity was 80.8% (AUC 0.850). The best triplet hsa-miR-6085, hsa-miR-6511b-5p, and hsa-miR-6886-5p allowed achieving 81.3% sensitivity at 80.8% specificity (AUC 0.860). For diagnostic panel consisting of all 6 miRNAs sensitivity reached 83.7% at specificity 84.6% (AUC 0.913). CONCLUSIONS: These results show high diagnostic potential of the panel of 6 circulating miRNAs (hsa-miR-155-5p, hsa-miR-619-5p, hsa-miR-6777-5p, hsa-miR-6085, hsa-miR-6511b-5p, and hsa-miR6886-5p) for minimally invasive diagnosis of prostate cancer which may improve the diagnostic accuracy of modern PC screening.

Tumour-like Druggable Gene Expression Pattern of CaCo2 Cells in Microfluidic Chip

2016 · ARTICLE · en

Modeling the metastatic cascade by in vitro microfluidic platforms

2015 · ARTICLE · en

miRNome of inflammatory breast cancer

2014 · ARTICLE · en

Background Inflammatory breast cancer (IBC) is an extremely malignant form of breast cancer which can be easily misdiagnosed. Conclusive prognostic IBC molecular biomarkers which are also providing the perspectives for targeted therapy are lacking so far. The aim of this study was to reveal the IBC-specific miRNA expression profile and to evaluate its association with clinicopathological parameters. Methods miRNA expression profiles of 13 IBC and 17 non-IBC patients were characterized using comprehensive Affymetrix GeneChip miRNA 3.0 microarray platform. Bioinformatic analysis was used to reveal IBC-specific miRNAs, deregulated pathways and potential miRNA targets. Results 31 differentially expressed miRNAs characterize IBC and mRNAs regulated by them and their associated pathways can functionally be attributed to IBC progression. In addition, a minimal predictive set of 4 miRNAs characteristic for the IBC phenotype and associated with the TP53 mutational status in breast cancer patients was identified. Conclusions We have characterized the complete miRNome of inflammatory breast cancer and found differentially expressed miRNAs which reliably classify the patients to IBC and non-IBC groups. We found that the mRNAs and pathways likely regulated by these miRNAs are highly relevant to cancer progression. Furthermore a minimal IBC-related predictive set of 4 miRNAs associated with the TP53 mutational status and survival for breast cancer patients was identified.