Arsen Arakelyan

Mr. Arsen Arakelyan

Institute for Molecular Biology, Academy of sciences of the Republic of Armenia, Yerevan, 7 Hasratyan Str, 0014, Armenia
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Research Focus & Metrics

Academic Career Length

23Years (2004-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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3 March 2023 in Science
Verified
Journal Article
Closed access
YDYang Dong
Yang Dong
SDShengchang Duan
Shengchang Duan
QXQiuju Xia
Qiuju Xia
ZLZhen-Chang Liang
Zhen-Chang Liang
XDXiao Dong
Xiao Dong
WCWei Chen
Wei Chen
We elucidate grapevine evolution and domestication histories with 3525 cultivated and wild accessions worldwide. In the Pleistocene, harsh climate drove the separation of wild grape ecotypes caused by continuous habitat fragmentation. Then, domestication occurred concurrently about 11,000 years ago in Western Asia and the Caucasus to yield table and wine grapevines. The Western Asia domesticates dispersed into Europe with early farmers, introgressed with ancient wild western ecotypes, and subsequently diversified along human migration trails into muscat and unique western wine grape ancestries by the late Neolithic. Analyses of domestication traits also reveal new insights into selection for berry palatability, hermaphroditism, muscat flavor, and berry skin color. These data demonstrate the role of the grapevines in the early inception of agriculture across Eurasia.

1 January 2005 in Mediators of Inflammation
Verified
Journal Article
Open access
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AAArsen Arakelyan
Arsen Arakelyan
JPJ. Petrkova
J. Petrkova
ZHZ. Hermanova
Z. Hermanova
ABA. Boyajyan
A. Boyajyan
JLJ. Lukl
J. Lukl
MPM. Petrek
M. Petrek
Chemokine‐driven migration of inflammatory cells has been implicated in pathogenesis of atherosclerosis‐associated conditions such as ischemic stroke and myocardial infarction. In this study, a candidate chemokine, monocyte chemoattractant protein (MCP)‐1, was investigated in patients with both aforementioned manifestations of atheroslerotic inflammation. MCP‐1 levels in serum were determined by ELISA in 40 healthy, control subjects (C), 40 patients with ischemic stroke (IS), and in 64 patients with myocardial infarction (MI). Statistical analysis utilised Mann‐Whitney test, Fisher′s exact test, and Spearman′s rank correlation (P < .05). In comparison to control subjects (C; median/interquartile range: 239/126 pg/mL), MCP‐1 serum levels were increased in both investigated patient cohorts (IS: 384/370, P < .001; MI: 360/200, P < .002). There was a substantial variability of MCP‐1 serum levels, especially in the IS group. No relationship was observed between chemokine levels and atherosclerosis risk factors (hypertension, diabetes, smoking, and alcohol consumption), and MCP‐1 was also not related to age or gender. Elevation of MCP‐1 in circulation of patients with atherosclerosis‐associated complications implicates this CC chemokine ligand (CCL)2 in inflammatory processes, which contribute to pathogenesis of myocardial infarction and ischemic stroke. Further investigations, including patient stratification, are however necessary to evaluate if MCP‐1 can be utilised for clinical management of patients with these diseases.

29 April 2015 in PLOS ONE
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Journal Article
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LNLilit Nersisyan
Lilit Nersisyan
AAArsen Arakelyan
Arsen Arakelyan
Telomeres are the ends of eukaryotic chromosomes, consisting of consecutive short repeats that protect chromosome ends from degradation. Telomeres shorten with each cell division, leading to replicative cell senescence. Deregulation of telomere length homeostasis is associated with the development of various age-related diseases and cancers. A number of experimental techniques exist for telomere length measurement; however, until recently, the absence of tools for extracting telomere lengths from high-throughput sequencing data has significantly obscured the association of telomere length with molecular processes in normal and diseased conditions. We have developed Computel, a program in R for computing mean telomere length from whole-genome next-generation sequencing data. Computel is open source, and is freely available at https://github.com/lilit-nersisyan/computel. It utilizes a short-read alignment-based approach and integrates various popular tools for sequencing data analysis. We validated it with synthetic and experimental data, and compared its performance with the previously available software. The results have shown that Computel outperforms existing software in accuracy, independence of results from sequencing conditions, stability against inherent sequencing errors, and better ability to distinguish pure telomeric sequences from interstitial telomeric repeats. By providing a highly reliable methodology for determining telomere lengths from whole-genome sequencing data, Computel should help to elucidate the role of telomeres in cellular health and disease.

3 November 2017 in PLOS ONE
Verified
Journal Article
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AAArsen Arakelyan
Arsen Arakelyan
LNLilit Nersisyan
Lilit Nersisyan
DPDavid Poghosyan
David Poghosyan
LKLusine Khondkaryan
Lusine Khondkaryan
AHAnna Hakobyan
Anna Hakobyan
Hans BinderHans Binder
Hans Binder
Autoinflammatory and autoimmune disorders are characterized by aberrant changes in innate and adaptive immunity that may lead from an initial inflammatory state to an organ specific damage. These disorders possess heterogeneity in terms of affected organs and clinical phenotypes. However, despite the differences in etiology and phenotypic variations, they share genetic associations, treatment responses and clinical manifestations. The mechanisms involved in their initiation and development remain poorly understood, however the existence of some clear similarities between autoimmune and autoinflammatory disorders indicates variable degrees of interaction between immune-related mechanisms. Our study aims at contributing to a holistic, pathway-centered view on the inflammatory condition of autoimmune and autoinflammatory diseases. We have evaluated similarities and specificities of pathway activity changes in twelve autoimmune and autoinflammatory disorders by performing meta-analysis of publicly available gene expression datasets generated from peripheral blood mononuclear cells, using a bioinformatics pipeline that integrates Self Organizing Maps and Pathway Signal Flow algorithms along with KEGG pathway topologies. The results reveal that clinically divergent disease groups share common pathway perturbation profiles. We identified pathways, similarly perturbed in all the studied diseases, such as PI3K-Akt, Toll-like receptor, and NF-kappa B signaling, that serve as integrators of signals guiding immune cell polarization, migration, growth, survival and differentiation. Further, two clusters of diseases were identified based on specifically dysregulated pathways: one gathering mostly autoimmune and the other mainly autoinflammatory diseases. Cluster separation was driven not only by apparent involvement of pathways implicated in adaptive immunity in one case, and inflammation in the other, but also by processes not explicitly related to immune response, but rather representing various events related to the formation of specific pathophysiological environment. Thus, our data suggest that while all of the studied diseases are affected by activation of common inflammatory processes, disease-specific variations in their relative balance are also identified.

20 July 2017 in The Journal of Pathology
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Hans BinderHans Binder
Hans Binder
LHLydia Hopp
Lydia Hopp
MSMichal R Schweiger
Michal R Schweiger
SHSteve Hoffmann
Steve Hoffmann
FJFrank Jühling
Frank Jühling
MLMarkus Loeffler
Markus Loeffler
Colorectal cancer (CRC) arising in Lynch syndrome (LS) comprises tumours with constitutional mutations in DNA mismatch repair genes. There is still a lack of whole‐genome and transcriptome studies of LS‐CRC to address questions about similarities and differences in mutation and gene expression characteristics between LS‐CRC and sporadic CRC, about the molecular heterogeneity of LS‐CRC, and about specific mechanisms of LS‐CRC genesis linked to dysfunctional mismatch repair in LS colonic mucosa and the possible role of immune editing. Here, we provide a first molecular characterization of LS tumours and of matched tumour‐distant reference colonic mucosa based on whole‐genome DNA‐sequencing and RNA‐sequencing analyses. Our data support two subgroups of LS‐CRCs, G1 and G2, whereby G1 tumours show a higher number of somatic mutations, a higher amount of microsatellite slippage, and a different mutation spectrum. The gene expression phenotypes support this difference. Reference mucosa of G1 shows a strong immune response associated with the expression of HLA and immune checkpoint genes and the invasion of CD4+ T cells. Such an immune response is not observed in LS tumours, G2 reference and normal (non‐Lynch) mucosa, and sporadic CRC. We hypothesize that G1 tumours are edited for escape from a highly immunogenic microenvironment via loss of HLA presentation and T‐cell exhaustion. In contrast, G2 tumours seem to develop in a less immunogenic microenvironment where tumour‐promoting inflammation parallels tumourigenesis. Larger studies on non‐neoplastic mucosa tissue of mutation carriers are required to better understand the early phases of emerging tumours. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

30 April 2019 in Genome Medicine
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FLfor the German Cancer Aid consortium Molecular Mechanisms for Malignant Lymphoma
for the German Cancer Aid consortium Molecular Mechanisms for Malignant Lymphoma
HLHenry Loeffler-Wirth
Henry Loeffler-Wirth
MKMarkus Kreuz
Markus Kreuz
LHLydia Hopp
Lydia Hopp
AAArsen Arakelyan
Arsen Arakelyan
Hans BinderHans Binder
Hans Binder
Germinal center-derived B cell lymphomas are tumors of the lymphoid tissues representing one of the most heterogeneous malignancies. Here we characterize the variety of transcriptomic phenotypes of this disease based on 873 biopsy specimens collected in the German Cancer Aid MMML (Molecular Mechanisms in Malignant Lymphoma) consortium. They include diffuse large B cell lymphoma (DLBCL), follicular lymphoma (FL), Burkitt’s lymphoma, mixed FL/DLBCL lymphomas, primary mediastinal large B cell lymphoma, multiple myeloma, IRF4-rearranged large cell lymphoma, MYC-negative Burkitt-like lymphoma with chr. 11q aberration and mantle cell lymphoma. We apply self-organizing map (SOM) machine learning to microarray-derived expression data to generate a holistic view on the transcriptome landscape of lymphomas, to describe the multidimensional nature of gene regulation and to pursue a modular view on co-expression. Expression data were complemented by pathological, genetic and clinical characteristics. We present a transcriptome map of B cell lymphomas that allows visual comparison between the SOM portraits of different lymphoma strata and individual cases. It decomposes into one dozen modules of co-expressed genes related to different functional categories, to genetic defects and to the pathogenesis of lymphomas. On a molecular level, this disease rather forms a continuum of expression states than clearly separated phenotypes. We introduced the concept of combinatorial pattern types (PATs) that stratifies the lymphomas into nine PAT groups and, on a coarser level, into five prominent cancer hallmark types with proliferation, inflammation and stroma signatures. Inflammation signatures in combination with healthy B cell and tonsil characteristics associate with better overall survival rates, while proliferation in combination with inflammation and plasma cell characteristics worsens it. A phenotypic similarity tree is presented that reveals possible progression paths along the transcriptional dimensions. Our analysis provided a novel look on the transition range between FL and DLBCL, on DLBCL with poor prognosis showing expression patterns resembling that of Burkitt’s lymphoma and particularly on ‘double-hit’ MYC and BCL2 transformed lymphomas. The transcriptome map provides a tool that aggregates, refines and visualizes the data collected in the MMML study and interprets them in the light of previous knowledge to provide orientation and support in current and future studies on lymphomas and on other cancer entities.