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  1. Article ; Online: OSCAA: A two-dimensional Gaussian mixture model for copy number variation association analysis.

    Yu, Xuanxuan / Luo, Xizhi / Cai, Guoshuai / Xiao, Feifei

    Genetic epidemiology

    2024  

    Abstract: Copy number variants (CNVs) are prevalent in the human genome and are found to have a profound effect on genomic organization and human diseases. Discovering disease-associated CNVs is critical for understanding the pathogenesis of diseases and aiding ... ...

    Abstract Copy number variants (CNVs) are prevalent in the human genome and are found to have a profound effect on genomic organization and human diseases. Discovering disease-associated CNVs is critical for understanding the pathogenesis of diseases and aiding their diagnosis and treatment. However, traditional methods for assessing the association between CNVs and disease risks adopt a two-stage strategy conducting quantitative CNV measurements first and then testing for association, which may lead to biased association estimation and low statistical power, serving as a major barrier in routine genome-wide assessment of such variation. In this article, we developed One-Stage CNV-disease Association Analysis (OSCAA), a flexible algorithm to discover disease-associated CNVs for both quantitative and qualitative traits. OSCAA employs a two-dimensional Gaussian mixture model that is built upon the PCs from copy number intensities, accounting for technical biases in CNV detection while simultaneously testing for their effect on outcome traits. In OSCAA, CNVs are identified and their associations with disease risk are evaluated simultaneously in a single step, taking into account the uncertainty of CNV identification in the statistical model. Our simulations demonstrated that OSCAA outperformed the existing one-stage method and traditional two-stage methods by yielding a more accurate estimate of the CNV-disease association, especially for short CNVs or CNVs with weak signals. In conclusion, OSCAA is a powerful and flexible approach for CNV association testing with high sensitivity and specificity, which can be easily applied to different traits and clinical risk predictions.
    Language English
    Publishing date 2024-03-27
    Publishing country United States
    Document type Journal Article
    ZDB-ID 605785-8
    ISSN 1098-2272 ; 0741-0395
    ISSN (online) 1098-2272
    ISSN 0741-0395
    DOI 10.1002/gepi.22558
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: A statistical learning method for simultaneous copy number estimation and subclone clustering with single-cell sequencing data.

    Qin, Fei / Cai, Guoshuai / Amos, Christopher I / Xiao, Feifei

    Genome research

    2024  Volume 34, Issue 1, Page(s) 85–93

    Abstract: The availability of single-cell sequencing (SCS) enables us to assess intra-tumor heterogeneity and identify cellular subclones without the confounding effect of mixed cells. Copy number aberrations (CNAs) have been commonly used to identify subclones in ...

    Abstract The availability of single-cell sequencing (SCS) enables us to assess intra-tumor heterogeneity and identify cellular subclones without the confounding effect of mixed cells. Copy number aberrations (CNAs) have been commonly used to identify subclones in SCS data using various clustering methods, as cells comprising a subpopulation are found to share a genetic profile. However, currently available methods may generate spurious results (e.g., falsely identified variants) in the procedure of CNA detection, thereby diminishing the accuracy of subclone identification within a large, complex cell population. In this study, we developed a subclone clustering method based on a fused lasso model, referred to as FLCNA, which can simultaneously detect CNAs in single-cell DNA sequencing (scDNA-seq) data. Spike-in simulations were conducted to evaluate the clustering and CNA detection performance of FLCNA, benchmarking it against existing copy number estimation methods (SCOPE, HMMcopy) in combination with commonly used clustering methods. Application of FLCNA to a scDNA-seq data set of breast cancer revealed different genomic variation patterns in neoadjuvant chemotherapy-treated samples and pretreated samples. We show that FLCNA is a practical and powerful method for subclone identification and CNA detection with scDNA-seq data.
    MeSH term(s) DNA Copy Number Variations ; Sequence Analysis, DNA/methods ; Base Sequence ; Cluster Analysis
    Language English
    Publishing date 2024-02-07
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1284872-4
    ISSN 1549-5469 ; 1088-9051 ; 1054-9803
    ISSN (online) 1549-5469
    ISSN 1088-9051 ; 1054-9803
    DOI 10.1101/gr.278098.123
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Corrigendum: A statistical learning method for simultaneous copy number estimation and subclone clustering with single-cell sequencing data.

    Qin, Fei / Cai, Guoshuai / Amos, Christopher I / Xiao, Feifei

    Genome research

    2024  Volume 34, Issue 3, Page(s) 514

    Language English
    Publishing date 2024-04-25
    Publishing country United States
    Document type Journal Article ; Published Erratum
    ZDB-ID 1284872-4
    ISSN 1549-5469 ; 1088-9051 ; 1054-9803
    ISSN (online) 1549-5469
    ISSN 1088-9051 ; 1054-9803
    DOI 10.1101/gr.279293.124
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: A statistical learning method for simultaneous copy number estimation and subclone clustering with single cell sequencing data.

    Qin, Fei / Cai, Guoshuai / Xiao, Feifei

    bioRxiv : the preprint server for biology

    2023  

    Abstract: The availability of single cell sequencing (SCS) enables us to assess intra-tumor heterogeneity and identify cellular subclones without the confounding effect of mixed cells. Copy number aberrations (CNAs) have been commonly used to identify subclones in ...

    Abstract The availability of single cell sequencing (SCS) enables us to assess intra-tumor heterogeneity and identify cellular subclones without the confounding effect of mixed cells. Copy number aberrations (CNAs) have been commonly used to identify subclones in SCS data using various clustering methods, since cells comprising a subpopulation are found to share genetic profile. However, currently available methods may generate spurious results (e.g., falsely identified CNAs) in the procedure of CNA detection, hence diminishing the accuracy of subclone identification from a large complex cell population. In this study, we developed a CNA detection method based on a fused lasso model, referred to as FLCNA, which can simultaneously identify subclones in single cell DNA sequencing (scDNA-seq) data. Spike-in simulations were conducted to evaluate the clustering and CNA detection performance of FLCNA benchmarking to existing copy number estimation methods (SCOPE, HMMcopy) in combination with the existing and commonly used clustering methods. Interestingly, application of FLCNA to a real scDNA-seq dataset of breast cancer revealed remarkably different genomic variation patterns in neoadjuvant chemotherapy treated samples and pre-treated samples. We show that FLCNA is a practical and powerful method in subclone identification and CNA detection with scDNA-seq data.
    Language English
    Publishing date 2023-04-20
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2023.04.18.537346
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: OSCAA: A Two-Dimensional Gaussian Mixture Model for Copy Number Variation Association Analysis.

    Yu, Xuanxuan / Luo, Xizhi / Cai, Guoshuai / Xiao, Feifei

    bioRxiv : the preprint server for biology

    2023  

    Abstract: Copy number variants (CNVs) are prevalent in the human genome which provide profound effect on genomic organization and human diseases. Discovering disease associated CNVs is critical for understanding the pathogenesis of diseases and aiding their ... ...

    Abstract Copy number variants (CNVs) are prevalent in the human genome which provide profound effect on genomic organization and human diseases. Discovering disease associated CNVs is critical for understanding the pathogenesis of diseases and aiding their diagnosis and treatment. However, traditional methods for assessing the association between CNVs and disease risks adopt a two-stage strategy conducting quantitative CNV measurements first and then testing for association, which may lead to biased association estimation and low statistical power, serving as a major barrier in routine genome wide assessment of such variation. In this article, we developed OSCAA, a flexible algorithm to discover disease associated CNVs for both quantitative and qualitative traits. OSCAA employs a two-dimensional Gaussian mixture model that is built upon the principal components from copy number intensities, accounting for technical biases in CNV detection while simultaneously testing for their effect on outcome traits. In OSCAA, CNVs are identified and their associations with disease risk are evaluated simultaneously in a single step, taking into account the uncertainty of CNV identification in the statistical model. Our simulations demonstrated that OSCAA outperformed the existing one-stage method and traditional two-stage methods by yielding a more accurate estimate of the CNV-disease association, especially for short CNVs or CNVs with weak signal. In conclusion, OSCAA is a powerful and flexible approach for CNV association testing with high sensitivity and specificity, which can be easily applied to different traits and clinical risk predictions.
    Language English
    Publishing date 2023-09-28
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2023.09.25.559392
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: The "Hand as Foot" teaching method in clinical staging of pharyngoesophageal diverticulum.

    Xiao, Feifei / Tian, Chunmei / Zhu, Shuxia

    Asian journal of surgery

    2022  

    Language English
    Publishing date 2022-07-13
    Publishing country China
    Document type Letter
    ZDB-ID 1068461-x
    ISSN 0219-3108 ; 1015-9584
    ISSN (online) 0219-3108
    ISSN 1015-9584
    DOI 10.1016/j.asjsur.2022.06.190
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: The "Hand as Foot" teaching method in anatomy of the appendix.

    Zhang, Haojie / Xiao, Feifei / Yang, Zhenlin / Sun, Hongguang

    Asian journal of surgery

    2022  Volume 45, Issue 10, Page(s) 1956–1957

    MeSH term(s) Appendix/surgery ; Foot/anatomy & histology ; Hand ; Humans ; Lower Extremity ; Upper Extremity
    Language English
    Publishing date 2022-04-16
    Publishing country China
    Document type Letter
    ZDB-ID 1068461-x
    ISSN 0219-3108 ; 1015-9584
    ISSN (online) 0219-3108
    ISSN 1015-9584
    DOI 10.1016/j.asjsur.2022.04.029
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: The "Hand as Foot" teaching method in lymphatic drainage of the mammary gland.

    Zhang, Haojie / Xiao, Feifei / Yang, Zhenlin / Sun, Hongguang

    Asian journal of surgery

    2022  Volume 45, Issue 10, Page(s) 1866–1867

    MeSH term(s) Hand ; Humans ; Lower Extremity ; Lymph Nodes ; Lymphatic Metastasis ; Mammary Glands, Human ; Upper Extremity
    Language English
    Publishing date 2022-04-09
    Publishing country China
    Document type Letter
    ZDB-ID 1068461-x
    ISSN 0219-3108 ; 1015-9584
    ISSN (online) 0219-3108
    ISSN 1015-9584
    DOI 10.1016/j.asjsur.2022.03.111
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: BISC: accurate inference of transcriptional bursting kinetics from single-cell transcriptomic data.

    Luo, Xizhi / Qin, Fei / Xiao, Feifei / Cai, Guoshuai

    Briefings in bioinformatics

    2022  Volume 23, Issue 6

    Abstract: Gene expression in mammalian cells is inherently stochastic and mRNAs are synthesized in discrete bursts. Single-cell transcriptomics provides an unprecedented opportunity to explore the transcriptome-wide kinetics of transcriptional bursting. However, ... ...

    Abstract Gene expression in mammalian cells is inherently stochastic and mRNAs are synthesized in discrete bursts. Single-cell transcriptomics provides an unprecedented opportunity to explore the transcriptome-wide kinetics of transcriptional bursting. However, current analysis methods provide limited accuracy in bursting inference due to substantial noise inherent to single-cell transcriptomic data. In this study, we developed BISC, a Bayesian method for inferring bursting parameters from single cell transcriptomic data. Based on a beta-gamma-Poisson model, BISC modeled the mean-variance dependency to achieve accurate estimation of bursting parameters from noisy data. Evaluation based on both simulation and real intron sequential RNA fluorescence in situ hybridization data showed improved accuracy and reliability of BISC over existing methods, especially for genes with low expression values. Further application of BISC found bursting frequency but not bursting size was strongly associated with gene expression regulation. Moreover, our analysis provided new mechanistic insights into the functional role of enhancer and superenhancer by modulating both bursting frequency and size. BISC also formulated a downstream framework to identify differential bursting (in frequency and size separately) genes in samples under different conditions. Applying to multiple datasets (a mouse embryonic cell and fibroblast dataset, a human immune cell dataset and a human pancreatic cell dataset), BISC identified known cell-type signature genes that were missed by differential expression analysis, providing additional insights in understanding the cell-specific stochastic gene transcription. Applying to datasets of human lung and colon cancers, BISC successfully detected tumor signature genes based on alterations in bursting kinetics, which illustrates its value in understanding disease development regarding transcriptional bursting. Collectively, BISC provides a new tool for accurately inferring bursting kinetics and detecting differential bursting genes. This study also produced new insights in the role of transcriptional bursting in regulating gene expression, cell identity and tumor progression.
    MeSH term(s) Animals ; Humans ; Mice ; Transcriptome ; In Situ Hybridization, Fluorescence ; Reproducibility of Results ; Bayes Theorem ; Kinetics ; Neoplasms ; Transcription, Genetic ; Mammals/genetics
    Language English
    Publishing date 2022-11-03
    Publishing country England
    Document type Journal Article
    ZDB-ID 2068142-2
    ISSN 1477-4054 ; 1467-5463
    ISSN (online) 1477-4054
    ISSN 1467-5463
    DOI 10.1093/bib/bbac464
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: SCANNER: a web platform for annotation, visualization and sharing of single cell RNA-seq data.

    Cai, Guoshuai / Yu, Xuanxuan / Youn, Choonhan / Zhou, Jun / Xiao, Feifei

    Database : the journal of biological databases and curation

    2022  Volume 2022

    Abstract: In recent years, efficient scRNA-seq methods have been developed, enabling the transcriptome profiling of single cells massively in parallel. Meanwhile, its high dimensionality and complexity bring challenges to the data analysis and require extensive ... ...

    Abstract In recent years, efficient scRNA-seq methods have been developed, enabling the transcriptome profiling of single cells massively in parallel. Meanwhile, its high dimensionality and complexity bring challenges to the data analysis and require extensive collaborations between biologists and bioinformaticians and/or biostatisticians. The communication between these two units demands a platform for easy data sharing and exploration. Here we developed Single-Cell Transcriptomics Annotated Viewer (SCANNER), as a public web resource for the scientific community, for sharing and analyzing scRNA-seq data in a collaborative manner. It is easy-to-use without requiring special software or extensive coding skills. Moreover, it equipped a real-time database for secure data management and enables an efficient investigation of the activation of gene sets on a single-cell basis. Currently, SCANNER hosts a database of 19 types of cancers and COVID-19, as well as healthy samples from lungs of smokers and non-smokers, human brain cells and peripheral blood mononuclear cells (PBMC). The database will be frequently updated with datasets from new studies. Using SCANNER, we identified a larger proportion of cancer-associated fibroblasts cells and more active fibroblast growth-related genes in melanoma tissues in female patients compared to male patients. Moreover, we found ACE2 is mainly expressed in lung pneumocytes, secretory cells and ciliated cells and differentially expressed in lungs of smokers and never smokers.
    MeSH term(s) COVID-19 ; Female ; Gene Expression Profiling ; Humans ; Leukocytes, Mononuclear ; Male ; RNA-Seq ; SARS-CoV-2 ; Sequence Analysis, RNA ; Single-Cell Analysis ; Software
    Language English
    Publishing date 2022-02-08
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2496706-3
    ISSN 1758-0463 ; 1758-0463
    ISSN (online) 1758-0463
    ISSN 1758-0463
    DOI 10.1093/database/baab086
    Database MEDical Literature Analysis and Retrieval System OnLINE

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