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  1. Article ; Online: Deep Pathway Analysis V2.0: A Pathway Analysis Framework Incorporating Multi-Dimensional Omics Data.

    Zhao, Yue / Shin, Dong-Guk

    IEEE/ACM transactions on computational biology and bioinformatics

    2021  Volume 18, Issue 1, Page(s) 373–385

    Abstract: Pathway analysis is essential in cancer research particularly when scientists attempt to derive interpretation from genome-wide high-throughput experimental data. If pathway information is organized into a network topology, its use in interpreting omics ... ...

    Abstract Pathway analysis is essential in cancer research particularly when scientists attempt to derive interpretation from genome-wide high-throughput experimental data. If pathway information is organized into a network topology, its use in interpreting omics data can become very powerful. In this paper, we propose a topology-based pathway analysis method, called DPA V2.0, which can combine multiple heterogeneous omics data types in its analysis. In this method, each pathway route is encoded as a Bayesian network which is initialized with a sequence of conditional probabilities specifically designed to encode directionality of regulatory relationships defined in the pathway. Unlike other topology-based pathway tools, DPA is capable of identifying pathway routes as representatives of perturbed regulatory signals. We demonstrate the effectiveness of our model by applying it to two well-established TCGA data sets, namely, breast cancer study (BRCA) and ovarian cancer study (OV). The analysis combines mRNA-seq, mutation, copy number variation, and phosphorylation data publicly available for both TCGA data sets. We performed survival analysis and patient subtype analysis and the analysis outcomes revealed the anticipated strengths of our model. We hope that the availability of our model encourages wet lab scientists to generate extra data sets to reap the benefits of using multiple data types in pathway analysis. The majority of pathways distinguished can be confirmed by biological literature. Moreover, the proportion of correctly indentified pathways is 10 percent higher than previous work where only mRNA-seq and mutation data is incorporated for breast cancer patients. Consequently, such an in-depth pathway analysis incorporating more diverse data can give rise to the accuracy of perturbed pathway detection.
    MeSH term(s) Algorithms ; Bayes Theorem ; Breast Neoplasms/genetics ; Breast Neoplasms/mortality ; Computational Biology/methods ; DNA Copy Number Variations/genetics ; Female ; Humans ; Mutation/genetics ; Ovarian Neoplasms/genetics ; Ovarian Neoplasms/mortality ; RNA-Seq ; Signal Transduction/genetics ; Survival Analysis ; Transcriptome/genetics
    Language English
    Publishing date 2021-02-03
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1557-9964
    ISSN (online) 1557-9964
    DOI 10.1109/TCBB.2019.2945959
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: vSPACE: Exploring Virtual Spatial Representation of Articular Chondrocytes at the Single-Cell Level.

    Zhang, Chenyu / Wang, Honglin / Hong, Seung-Hyun / Olmer, Merissa / Swahn, Hannah / Lotz, Martin K / Maye, Peter / Rowe, David / Shin, Dong-Guk

    bioRxiv : the preprint server for biology

    2024  

    Abstract: Single cell RNA sequencing technology has been dramatically changing how gene expression studies are performed. However, its use has been limited to identifying subtypes of cells by comparing cells' gene expression levels in an unbiased manner to produce ...

    Abstract Single cell RNA sequencing technology has been dramatically changing how gene expression studies are performed. However, its use has been limited to identifying subtypes of cells by comparing cells' gene expression levels in an unbiased manner to produce a 2D plot (e.g., UMAP/tSNE). We developed a new method of placing cells in 2D space. This system, called vSPACE, shows a virtual spatial representation of scRNAseq data obtained from human articular cartilage by emulating the concept of spatial transcriptomics technology, but virtually. This virtual 2D plot presentation of human articular cartage cells generates several zonal distribution patterns, in one or multiple genes at a time, reveling patterns that scientists can appreciate as imputed spatial distribution patterns along the zonal axis. The discovered patterns are explainable and remarkably consistent across all six healthy doners despite their respectively different clinical variables (age and sex), suggesting the confidence of the discovered patterns.
    Language English
    Publishing date 2024-02-10
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2024.02.07.577817
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: CGCom: a framework for inferring Cell-cell Communication based on Graph Neural Network.

    Wang, Honglin / Zhang, Chenyu / Hong, Seung-Hyun / Maye, Peter / Rowe, David / Shin, Dong-Guk

    bioRxiv : the preprint server for biology

    2023  

    Abstract: Cell-cell communication is crucial in maintaining cellular homeostasis, cell survival and various regulatory relationships among interacting cells. Thanks to recent advances of spatial transcriptomics technologies, we can now explore if and how cells' ... ...

    Abstract Cell-cell communication is crucial in maintaining cellular homeostasis, cell survival and various regulatory relationships among interacting cells. Thanks to recent advances of spatial transcriptomics technologies, we can now explore if and how cells' proximal information available from spatial transcriptomics datasets can be used to infer cell-cell communication. Here we present a cell-cell communication inference framework, called CGCom, which uses a graph neural network (GNN) to learn communication patterns among interacting cells by combining single-cell spatial transcriptomic datasets with publicly available ligand-receptor information and the molecular regulatory information down-stream of the ligand-receptor signaling. To evaluate the performance of CGCom, we applied it to mouse embryo seqFISH datasets. Our results demonstrate that CGCom can not only accurately infer cell communication between individual cell pairs but also generalize its learning to predict communication between different cell types. We compared the performance of CGCom with two existing methods, CellChat and CellPhoneDB, and our comparative study revealed both common and unique communication patterns from the three approaches. Commonly found communication patterns include three sets of ligand-receptor communication relationships, one between surface ectoderm cells and spinal cord cells, one between gut tube cells and endothelium, and one between neural crest and endothelium, all of which have already been reported in the literature thus offering credibility of all three methods. However, we hypothesize that CGCom is superior in reducing false positives thanks to its use of cell proximal information and its learning between specific cell pairs rather than between cell types. CGCom is a GNN-based solution that can take advantage of spatially resolved single-cell transcriptomic data in predicting cell-cell communication with a higher accuracy.
    Language English
    Publishing date 2023-11-15
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2023.11.10.566642
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: rPAC: Route based pathway analysis for cohorts of gene expression data sets

    Joshi, Pujan / Basso, Brent / Wang, Honglin / Hong, Seung-Hyun / Giardina, Charles / Shin, Dong-Guk

    Methods. 2022 Feb., v. 198

    2022  

    Abstract: Pathway analysis is a popular method aiming to derive biological interpretation from high-throughput gene expression studies. However, existing methods focus mostly on identifying which pathway or pathways could have been perturbed, given differential ... ...

    Abstract Pathway analysis is a popular method aiming to derive biological interpretation from high-throughput gene expression studies. However, existing methods focus mostly on identifying which pathway or pathways could have been perturbed, given differential gene expression patterns. In this paper, we present a novel pathway analysis framework, namely rPAC, which decomposes each signaling pathway route into two parts, the upstream portion of a transcription factor (TF) block and the downstream portion from the TF block and generates a pathway route perturbation analysis scheme examining disturbance scores assigned to both parts together. This rPAC scoring is further applied to a cohort of gene expression data sets which produces two summary metrics, “Proportion of Significance” (PS) and “Average Route Score” (ARS), as quantitative measures discerning perturbed pathway routes within and/or between cohorts. To demonstrate rPAC’s scoring competency, we first used a large amount of simulated data and compared the method’s performance against those by conventional methods in terms of power curve. Next, we performed a case study involving three epithelial cancer data sets from The Cancer Genome Atlas (TCGA). The rPAC method revealed specific pathway routes as potential cancer type signatures. A deeper pathway analysis of sub-groups (i.e., age groups in COAD or cancer sub-types in BRCA) resulted in pathway routes that are known to be associated with the sub-groups. In addition, multiple previously uncharacterized pathways routes were identified, potentially suggesting that rPAC is better in deciphering etiology of a disease than conventional methods particularly in isolating routes and sections of perturbed pathways in a finer granularity.
    Keywords case studies ; epithelium ; etiology ; gene expression ; gene expression regulation ; genome ; transcription factors
    Language English
    Dates of publication 2022-02
    Size p. 76-87.
    Publishing place Elsevier Inc.
    Document type Article
    ZDB-ID 1066584-5
    ISSN 1095-9130 ; 1046-2023
    ISSN (online) 1095-9130
    ISSN 1046-2023
    DOI 10.1016/j.ymeth.2021.10.002
    Database NAL-Catalogue (AGRICOLA)

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  5. Article ; Online: TriPOINT: a software tool to prioritize important genes in pathways and their non-coding regulators.

    Thibodeau, Asa / Shin, Dong-Guk

    Bioinformatics (Oxford, England)

    2018  Volume 35, Issue 15, Page(s) 2686–2689

    Abstract: Summary: Current approaches for pathway analyses focus on representing gene expression levels on graph representations of pathways and conducting pathway enrichment among differentially expressed genes. However, gene expression levels by themselves do ... ...

    Abstract Summary: Current approaches for pathway analyses focus on representing gene expression levels on graph representations of pathways and conducting pathway enrichment among differentially expressed genes. However, gene expression levels by themselves do not reflect the overall picture as non-coding factors play an important role to regulate gene expression. To incorporate these non-coding factors into pathway analyses and to systematically prioritize genes in a pathway we introduce a new software: Triangulation of Perturbation Origins and Identification of Non-Coding Targets. Triangulation of Perturbation Origins and Identification of Non-Coding Targets is a pathway analysis tool, implemented in Java that identifies the significance of a gene under a condition (e.g. a disease phenotype) by studying graph representations of pathways, analyzing upstream and downstream gene interactions and integrating non-coding regions that may be regulating gene expression levels.
    Availability and implementation: The TriPOINT open source software is freely available at https://github.uconn.edu/ajt06004/TriPOINT under the GPL v3.0 license.
    Supplementary information: Supplementary data are available at Bioinformatics online.
    MeSH term(s) Gene Expression ; Software
    Language English
    Publishing date 2018-11-22
    Publishing country England
    Document type Journal Article
    ZDB-ID 1422668-6
    ISSN 1367-4811 ; 1367-4803
    ISSN (online) 1367-4811
    ISSN 1367-4803
    DOI 10.1093/bioinformatics/bty998
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Predicting the targets of IRF8 and NFATc1 during osteoclast differentiation using the machine learning method framework cTAP.

    Wang, Honglin / Joshi, Pujan / Hong, Seung-Hyun / Maye, Peter F / Rowe, David W / Shin, Dong-Guk

    BMC genomics

    2022  Volume 23, Issue 1, Page(s) 14

    Abstract: Background: Interferon regulatory factor-8 (IRF8) and nuclear factor-activated T cells c1 (NFATc1) are two transcription factors that have an important role in osteoclast differentiation. Thanks to ChIP-seq technology, scientists can now estimate ... ...

    Abstract Background: Interferon regulatory factor-8 (IRF8) and nuclear factor-activated T cells c1 (NFATc1) are two transcription factors that have an important role in osteoclast differentiation. Thanks to ChIP-seq technology, scientists can now estimate potential genome-wide target genes of IRF8 and NFATc1. However, finding target genes that are consistently up-regulated or down-regulated across different studies is hard because it requires analysis of a large number of high-throughput expression studies from a comparable context.
    Method: We have developed a machine learning based method, called, Cohort-based TF target prediction system (cTAP) to overcome this problem. This method assumes that the pathway involving the transcription factors of interest is featured with multiple "functional groups" of marker genes pertaining to the concerned biological process. It uses two notions, Gene-Present Sufficiently (GP) and Gene-Absent Insufficiently (GA), in addition to log2 fold changes of differentially expressed genes for the prediction. Target prediction is made by applying multiple machine-learning models, which learn the patterns of GP and GA from log2 fold changes and four types of Z scores from the normalized cohort's gene expression data. The learned patterns are then associated with the putative transcription factor targets to identify genes that consistently exhibit Up/Down gene regulation patterns within the cohort. We applied this method to 11 publicly available GEO data sets related to osteoclastgenesis.
    Result: Our experiment identified a small number of Up/Down IRF8 and NFATc1 target genes as relevant to osteoclast differentiation. The machine learning models using GP and GA produced NFATc1 and IRF8 target genes different than simply using a log2 fold change alone. Our literature survey revealed that all predicted target genes have known roles in bone remodeling, specifically related to the immune system and osteoclast formation and functions, suggesting confidence and validity in our method.
    Conclusion: cTAP was motivated by recognizing that biologists tend to use Z score values present in data sets for the analysis. However, using cTAP effectively presupposes assembling a sizable cohort of gene expression data sets within a comparable context. As public gene expression data repositories grow, the need to use cohort-based analysis method like cTAP will become increasingly important.
    MeSH term(s) Cell Differentiation ; Humans ; Interferon Regulatory Factors/genetics ; Interferon Regulatory Factors/metabolism ; Machine Learning ; NFATC Transcription Factors/genetics ; NFATC Transcription Factors/metabolism ; Osteoclasts/metabolism ; RANK Ligand/metabolism ; T-Lymphocytes/metabolism
    Chemical Substances Interferon Regulatory Factors ; NFATC Transcription Factors ; NFATC1 protein, human ; RANK Ligand ; interferon regulatory factor-8
    Language English
    Publishing date 2022-01-07
    Publishing country England
    Document type Journal Article
    ZDB-ID 2041499-7
    ISSN 1471-2164 ; 1471-2164
    ISSN (online) 1471-2164
    ISSN 1471-2164
    DOI 10.1186/s12864-021-08159-z
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: The chromatin accessibility landscape in the dental pulp of mouse molars and incisors.

    Joshi, Pujan / Vijaykumar, Anushree / Enkhmandakh, Badam / Shin, Dong-Guk / Mina, Mina / Bayarsaihan, Dashzeveg

    Acta biochimica Polonica

    2022  Volume 69, Issue 1, Page(s) 131–138

    Abstract: The dental pulp is a promising source of progenitor cells for regenerative medicine. The natural function of dental pulp is to produce odontoblasts to generate reparative dentin. Stem cells within the pulp tissue originate from the migrating neural crest ...

    Abstract The dental pulp is a promising source of progenitor cells for regenerative medicine. The natural function of dental pulp is to produce odontoblasts to generate reparative dentin. Stem cells within the pulp tissue originate from the migrating neural crest cells and possess mesenchymal stem cell properties with the ability to differentiate into multiple lineages. To elucidate the transcriptional control mechanisms underlying cell fate determination, we compared the transcriptome and chromatin accessibility in primary dental pulp tissue derived from 5-6-day-old mice. Using RNA sequencing and assay for transposase-accessible chromatin using sequencing (ATAC-seq), we correlated gene expression with chromatin accessibility. We found that the majority of ATAC-seq peaks were concentrated at genes associated with development and cell differentiation. Most of these genes were highly expressed in the mouse dental pulp. Surprisingly, we uncovered a group of genes encoding master transcription factors that were not expressed in the dental pulp but retained open chromatin states. Within this group, we identified key developmental genes important for specification of the neural crest, adipocyte, neural, myoblast, osteoblast and hepatocyte lineages. Collectively, our results uncover a complex relationship between gene expression and the chromatin accessibility landscape in the mouse dental pulp.
    MeSH term(s) Adipocytes/metabolism ; Animals ; Cell Differentiation ; Chromatin/genetics ; Chromatin/metabolism ; Chromatin Immunoprecipitation Sequencing/methods ; Dental Pulp/metabolism ; Gene Expression ; Incisor/metabolism ; Mesenchymal Stem Cells/metabolism ; Mice ; Odontoblasts/metabolism ; Regenerative Medicine/methods ; Stem Cells/metabolism ; Transcription Factors/metabolism
    Chemical Substances Chromatin ; Transcription Factors
    Language English
    Publishing date 2022-02-28
    Publishing country Poland
    Document type Journal Article
    ZDB-ID 595762-x
    ISSN 1734-154X ; 0001-527X
    ISSN (online) 1734-154X
    ISSN 0001-527X
    DOI 10.18388/abp.2020_5771
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Single-cell transcriptomics defines Dot1L interacting partners and downstream target genes in the mouse molar dental pulp.

    Guzzo, Rosa / Enkhmandakh, Badam / Becker, Timothy / Joshi, Pujan / Robson, Paul / Vijaykumar, Anushree / Mina, Mina / Shin, Dong-Guk / Bayarsaihan, Dashzeveg

    The International journal of developmental biology

    2023  Volume 66, Issue 7-8-9, Page(s) 391–400

    Abstract: Although histone methyltransferases are implicated in many key developmental processes, the contribution of individual chromatin modifiers in dental tissues is not well understood. Using single-cell RNA sequencing, we examined the expression profiles of ... ...

    Abstract Although histone methyltransferases are implicated in many key developmental processes, the contribution of individual chromatin modifiers in dental tissues is not well understood. Using single-cell RNA sequencing, we examined the expression profiles of the disruptor of telomeric silencing 1-like (
    MeSH term(s) Animals ; Mice ; Methyltransferases/genetics ; Methyltransferases/metabolism ; Transcription Factors/genetics ; Transcriptome ; Dental Pulp/metabolism ; Endothelial Cells ; Nuclear Proteins/metabolism ; Osteogenesis ; Histone-Lysine N-Methyltransferase/genetics ; Histone-Lysine N-Methyltransferase/metabolism
    Chemical Substances Methyltransferases (EC 2.1.1.-) ; Transcription Factors ; Nuclear Proteins ; Dot1l protein, mouse (EC 2.1.1.-) ; Histone-Lysine N-Methyltransferase (EC 2.1.1.43)
    Language English
    Publishing date 2023-03-21
    Publishing country Spain
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1036070-0
    ISSN 1696-3547 ; 0214-6282
    ISSN (online) 1696-3547
    ISSN 0214-6282
    DOI 10.1387/ijdb.220141db
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: A Novel Epi-drug Therapy Based on the Suppression of BET Family Epigenetic Readers.

    Shin, Dong-Guk / Bayarsaihan, Dashzeveg

    The Yale journal of biology and medicine

    2017  Volume 90, Issue 1, Page(s) 63–71

    Abstract: Recent progress in epigenetic research has made a profound influence on pharmacoepigenomics, one of the fastest growing disciplines promising to provide new epi-drugs for the treatment of a broad range of diseases. Histone acetylation is among the most ... ...

    Abstract Recent progress in epigenetic research has made a profound influence on pharmacoepigenomics, one of the fastest growing disciplines promising to provide new epi-drugs for the treatment of a broad range of diseases. Histone acetylation is among the most essential chromatin modifications underlying the dynamics of transcriptional activation. The acetylated genomic regions recruit the BET (bromodomain and extra-terminal) family of bromodomains (BRDs), thereby serving as a molecular scaffold in establishing RNA polymerase II specificity. Over the past several years, the BET epigenetic readers have become the main targets for drug therapy. The discovery of selective small-molecule compounds with capacity to inhibit BET proteins has paved a path for developing novel strategies against cancer, cardiovascular, skeletal, and inflammatory diseases. Therefore, further research into small chemicals impeding the regulatory activity of BRDs could offer therapeutic benefits for many health problems including tumor growth, heart disease, oral, and bone disorders.
    MeSH term(s) Acetylation ; Animals ; Epigenesis, Genetic/genetics ; Histones/metabolism ; Humans ; RNA Polymerase II/metabolism
    Chemical Substances Histones ; RNA Polymerase II (EC 2.7.7.-)
    Language English
    Publishing date 2017-03-29
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 200515-3
    ISSN 1551-4056 ; 0044-0086
    ISSN (online) 1551-4056
    ISSN 0044-0086
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Single-cell Transcriptome Landscape of DNA Methylome Regulators Associated with Orofacial Clefts in the Mouse Dental Pulp.

    Enkhmandakh, Badam / Joshi, Pujan / Robson, Paul / Vijaykumar, Anushree / Mina, Mina / Shin, Dong-Guk / Bayarsaihan, Dashzeveg

    The Cleft palate-craniofacial journal : official publication of the American Cleft Palate-Craniofacial Association

    2023  , Page(s) 10556656231172296

    Abstract: Objective: Significant evidence links epigenetic processes governing the dynamics of DNA methylation and demethylation to an increased risk of syndromic and nonsyndromic cleft lip and/or cleft palate (CL/P). Previously, we characterized mesenchymal stem/ ...

    Abstract Objective: Significant evidence links epigenetic processes governing the dynamics of DNA methylation and demethylation to an increased risk of syndromic and nonsyndromic cleft lip and/or cleft palate (CL/P). Previously, we characterized mesenchymal stem/stromal cells (MSCs) at different stages of osteogenic differentiation in the mouse incisor dental pulp. The main objective of this research was to characterize the transcriptional landscape of regulatory genes associated with DNA methylation and demethylation at a single-cell resolution.
    Design: We used single-cell RNA sequencing (scRNA-seq) data to characterize transcriptome in individual subpopulations of MSCs in the mouse incisor dental pulp.
    Settings: The biomedical research institution.
    Patients/participants: This study did not include patients.
    Interventions: This study collected and analyzed data on the single-cell RNA expssion in the mouse incisor dental pulp.
    Main outcome measure(s): Molecular regulators of DNA methylation/demethylation exhibit differential transcriptional landscape in different subpopulations of osteogenic progenitor cells.
    Results: scRNA-seq analysis revealed that genes encoding DNA methylation and demethylation enzymes (DNA methyltransferases and members of the ten-eleven translocation family of methylcytosine dioxygenases), methyl-DNA binding domain proteins, as well as transcription factors and chromatin remodeling proteins that cooperate with DNA methylation machinery are differentially expressed within distinct subpopulations of MSCs that undergo different stages of osteogenic differentiation.
    Conclusions: These findings suggest some mechanistic insights into a potential link between epigenetic alterations and multifactorial causes of CL/P phenotypes.
    Language English
    Publishing date 2023-05-09
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1069409-2
    ISSN 1545-1569 ; 0009-8701 ; 1055-6656
    ISSN (online) 1545-1569
    ISSN 0009-8701 ; 1055-6656
    DOI 10.1177/10556656231172296
    Database MEDical Literature Analysis and Retrieval System OnLINE

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