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1.
PLoS Pathog ; 20(7): e1012344, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38976714

RESUMO

AAV-mediated gene therapy typically requires a high dose of viral transduction, risking acute immune responses and patient safety, part of which is due to limited understanding of the host-viral interactions, especially post-transduction viral genome processing. Here, through a genome-wide CRISPR screen, we identified SMCHD1 (Structural Maintenance of Chromosomes Hinge Domain 1), an epigenetic modifier, as a critical broad-spectrum restricting host factor for post-entry AAV transgene expression. SMCHD1 knock-down by RNAi and CRISPRi or knock-out by CRISPR all resulted in significantly enhanced transgene expression across multiple viral serotypes, as well as for both single-strand and self-complementary AAV genome types. Mechanistically, upon viral transduction, SMCHD1 effectively repressed AAV transcription by the formation of an LRIF1-HP1-containing protein complex and directly binding with the AAV genome to maintain a heterochromatin-like state. SMCHD1-KO or LRIF1-KD could disrupt such a complex and thus result in AAV transcriptional activation. Together, our results highlight the host factor-induced chromatin remodeling as a critical inhibitory mechanism for AAV transduction and may shed light on further improvement in AAV-based gene therapy.


Assuntos
Proteínas Cromossômicas não Histona , Dependovirus , Transdução Genética , Dependovirus/genética , Humanos , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Sistemas CRISPR-Cas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Células HEK293 , Genoma Viral , Terapia Genética/métodos
2.
BMC Genomics ; 25(1): 167, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347478

RESUMO

The most widely practiced strategy for constructing the deep learning (DL) prediction model for drug resistance of Mycobacterium tuberculosis (MTB) involves the adoption of ready-made and state-of-the-art architectures usually proposed for non-biological problems. However, the ultimate goal is to construct a customized model for predicting the drug resistance of MTB and eventually for the biological phenotypes based on genotypes. Here, we constructed a DL training framework to standardize and modularize each step during the training process using the latest tensorflow 2 API. A systematic and comprehensive evaluation of each module in the three currently representative models, including Convolutional Neural Network, Denoising Autoencoder, and Wide & Deep, which were adopted by CNNGWP, DeepAMR, and WDNN, respectively, was performed in this framework regarding module contributions in order to assemble a novel model with proper dedicated modules. Based on the whole-genome level mutations, a de novo learning method was developed to overcome the intrinsic limitations of previous models that rely on known drug resistance-associated loci. A customized DL model with the multilayer perceptron architecture was constructed and achieved a competitive performance (the mean sensitivity and specificity were 0.90 and 0.87, respectively) compared to previous ones. The new model developed was applied in an end-to-end user-friendly graphical tool named TB-DROP (TuBerculosis Drug Resistance Optimal Prediction: https://github.com/nottwy/TB-DROP ), in which users only provide sequencing data and TB-DROP will complete analysis within several minutes for one sample. Our study contributes to both a new strategy of model construction and clinical application of deep learning-based drug-resistance prediction methods.


Assuntos
Aprendizado Profundo , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Humanos , Mycobacterium tuberculosis/genética , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Tuberculose/microbiologia , Mutação , Testes de Sensibilidade Microbiana , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
3.
BMC Bioinformatics ; 24(1): 463, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38062357

RESUMO

Single-cell sequencing has shed light on previously inaccessible biological questions from different fields of research, including organism development, immune function, and disease progression. The number of single-cell-based studies increased dramatically over the past decade. Several new methods and tools have been continuously developed, making it extremely tricky to navigate this research landscape and develop an up-to-date workflow to analyze single-cell sequencing data, particularly for researchers seeking to enter this field without computational experience. Moreover, choosing appropriate tools and optimal parameters to meet the demands of researchers represents a major challenge in processing single-cell sequencing data. However, a specific resource for easy access to detailed information on single-cell sequencing methods and data processing pipelines is still lacking. In the present study, an online resource called SingleScan was developed to curate all up-to-date single-cell transcriptome/genome analyzing tools and pipelines. All the available tools were categorized according to their main tasks, and several typical workflows for single-cell data analysis were summarized. In addition, spatial transcriptomics, which is a breakthrough molecular analysis method that enables researchers to measure all gene activity in tissue samples and map the site of activity, was included along with a portion of single-cell and spatial analysis solutions. For each processing step, the available tools and specific parameters used in published articles are provided and how these parameters affect the results is shown in the resource. All information used in the resource was manually extracted from related literature. An interactive website was designed for data retrieval, visualization, and download. By analyzing the included tools and literature, users can gain insights into the trends of single-cell studies and easily grasp the specific usage of a specific tool. SingleScan will facilitate the analysis of single-cell sequencing data and promote the development of new tools to meet the growing and diverse needs of the research community. The SingleScan database is publicly accessible via the website at http://cailab.labshare.cn/SingleScan .


Assuntos
Genoma , Software , Bases de Dados Factuais , Armazenamento e Recuperação da Informação , Transcriptoma
4.
BMC Genomics ; 24(1): 678, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37950200

RESUMO

BACKGROUND: High oncogene expression in cancer cells is a major cause of rapid tumor progression and drug resistance. Recent cancer genome research has shown that oncogenes as well as regulatory elements can be amplified in the form of extrachromosomal DNA (ecDNA) or subsequently integrated into chromosomes as homogeneously staining regions (HSRs). These genome-level variants lead to the overexpression of the corresponding oncogenes, resulting in poor prognosis. Most existing detection methods identify ecDNA using whole genome sequencing (WGS) data. However, these techniques usually detect many false positive regions owing to chromosomal DNA interference. RESULTS: In the present study, an algorithm called "ATACAmp" that can identify ecDNA/HSRs in tumor genomes using ATAC-seq data has been described. High chromatin accessibility, one of the characteristics of ecDNA, makes ATAC-seq naturally enriched in ecDNA and reduces chromosomal DNA interference. The algorithm was validated using ATAC-seq data from cell lines that have been experimentally determined to contain ecDNA regions. ATACAmp accurately identified the majority of validated ecDNA regions. AmpliconArchitect, the widely used ecDNA detecting tool, was used to detect ecDNA regions based on the WGS data of the same cell lines. Additionally, the Circle-finder software, another tool that utilizes ATAC-seq data, was assessed. The results showed that ATACAmp exhibited higher accuracy than AmpliconArchitect and Circle-finder. Moreover, ATACAmp supported the analysis of single-cell ATAC-seq data, which linked ecDNA to specific cells. CONCLUSIONS: ATACAmp, written in Python, is freely available on GitHub under the MIT license: https://github.com/chsmiss/ATAC-amp . Using ATAC-seq data, ATACAmp offers a novel analytical approach that is distinct from the conventional use of WGS data. Thus, this method has the potential to reduce the cost and technical complexity associated ecDNA analysis.


Assuntos
DNA de Forma B , Neoplasias , Humanos , Sequenciamento de Cromatina por Imunoprecipitação , Cromatina , DNA/genética , Oncogenes , Neoplasias/genética
5.
Nucleic Acids Res ; 48(D1): D797-D806, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31701131

RESUMO

Comprehensive genomic analyses of cancers have revealed substantial intrapatient molecular heterogeneities that may explain some instances of drug resistance and treatment failures. Examination of the clonal composition of an individual tumor and its evolution through disease progression and treatment may enable identification of precise therapeutic targets for drug design. Multi-region and single-cell sequencing are powerful tools that can be used to capture intratumor heterogeneity. Here, we present a database we've named CancerTracer (http://cailab.labshare.cn/cancertracer): a manually curated database designed to track and characterize the evolutionary trajectories of tumor growth in individual patients. We collected over 6000 tumor samples from 1548 patients corresponding to 45 different types of cancer. Patient-specific tumor phylogenetic trees were constructed based on somatic mutations or copy number alterations identified in multiple biopsies. Using the structured heterogeneity data, researchers can identify common driver events shared by all tumor regions, and the heterogeneous somatic events present in different regions of a tumor of interest. The database can also be used to investigate the phylogenetic relationships between primary and metastatic tumors. It is our hope that CancerTracer will significantly improve our understanding of the evolutionary histories of tumors, and may facilitate the identification of predictive biomarkers for personalized cancer therapies.


Assuntos
Bases de Dados Factuais , Progressão da Doença , Neoplasias , Biomarcadores Tumorais/genética , Heterogeneidade Genética , Humanos , Mutação , Neoplasias/classificação , Neoplasias/genética , Neoplasias/patologia , Fenótipo , Filogenia
6.
Nucleic Acids Res ; 47(W1): W610-W613, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31066442

RESUMO

Quality control (QC) for lab-designed primers is crucial for the success of a polymerase chain reaction (PCR). Here, we present MFEprimer-3.0, a functional primer quality control program for checking non-specific amplicons, dimers, hairpins and other parameters. The new features of the current version include: (i) more sensitive binding site search using the updated k-mer algorithm that allows mismatches within the k-mer, except for the first base at the 3' end. The binding sites of each primer with a stable 3' end are listed in the output; (ii) new algorithms for rapidly identifying self-dimers, cross-dimers and hairpins; (iii) the command-line version, which has an added option of JSON output to enhance the versatility of MFEprimer by acting as a QC step in the 'primer design → quality control → redesign' pipeline; (iv) a function for checking whether the binding sites contain single nucleotide polymorphisms (SNPs), which will affect the consistency of binding efficiency among different samples. In summary, MFEprimer-3.0 is updated with the well-tested PCR primer QC program and it can be integrated into various PCR primer design applications as a QC module. The MFEprimer-3.0 server is freely accessible without any login requirement at: https://mfeprimer3.igenetech.com/ and https://www.mfeprimer.com/. The source code for the command-line version is available upon request.


Assuntos
Primers do DNA/normas , Reação em Cadeia da Polimerase/normas , Software , Algoritmos , Pareamento Incorreto de Bases , Sítios de Ligação , Primers do DNA/química , Genoma Humano , Humanos , Reação em Cadeia da Polimerase Multiplex/normas , Controle de Qualidade , Análise de Sequência
7.
BMC Genomics ; 21(1): 201, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32131721

RESUMO

BACKGROUND: The yak is a species of livestock which is crucial for local communities of the Qinghai-Tibet Plateau and adjacent regions and naturally owns one more thoracic vertebra than cattle. Recently, a sub-population of yak termed as the Jinchuan yak has been identified with over half its members own a thoracolumbar vertebral formula of T15L5 instead of the natural T14L5 arrangement. The novel T15L5 positioning is a preferred genetic trait leading to enhanced meat and milk production. Selective breeding of this trait would have great agricultural value and exploration of the molecular mechanisms underlying this trait would both accelerate this process and provide us insight into the development and regulation of somitogenesis. RESULTS: Here we investigated the genetic background of the Jinchuan yak through resequencing fifteen individuals, comprising five T15L5 individuals and ten T14L5 individuals with an average sequencing depth of > 10X, whose thoracolumbar vertebral formulae were confirmed by anatomical observation. Principal component analysis, linkage disequilibrium analysis, phylogenetic analysis, and selective sweep analysis were carried out to explore Jinchuan yak's genetic background. Three hundred and thirty candidate markers were identified as associated with the additional thoracic vertebrae and target sequencing was used to validate seven carefully selected markers in an additional 51 Jinchuan yaks. The accuracies of predicting 15 thoracic vertebrae and 20 thoracolumbar vertebrae with these 7 markers were 100.00 and 33.33% despite they both could only represent 20% of all possible genetic diversity. Two genes, PPP2R2B and TBLR1, were found to harbour the most candidate markers associated with the trait and likely contribute to the unique somitic number and identity according to their reported roles in the mechanism of somitogenesis. CONCLUSIONS: Our findings provide a clear depiction of the Jinchuan yak's genetic background and a solid foundation for marker-assistant selection. Further exploitation of this unique population and trait could be promoted with the aid of our genomic resource.


Assuntos
Locos de Características Quantitativas , Somitos/crescimento & desenvolvimento , Vértebras Torácicas/anatomia & histologia , Sequenciamento Completo do Genoma/veterinária , Animais , Cruzamento , Bovinos , Heterogeneidade Genética , Desequilíbrio de Ligação , Fenótipo , Filogenia , Tibet
8.
Mol Genet Genomics ; 295(3): 765-773, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31901979

RESUMO

Cervical cancer is a common gynecological malignancy with high incidence and mortality. Somatic copy number alterations (CNAs) play an important role in identifying tumor suppressor genes and oncogenes and are a useful diagnostic indicator for many cancer types. However, the genomic landscape of CNAs in cervical cancer has not yet been comprehensively characterized. In the present study, we collected 974 cervical cancer samples from different data sources. All samples were analyzed by genomic arrays to obtain high-resolution CNAs. Focal genomic regions with CNA events and potential cancer driver genes were identified by GISTIC2.0. Meanwhile, we constructed a comprehensive cervical cancer database by PHP and self-written Perl and R scripts. In total, 54 recurrent regions of amplification and deletion were detected. Frequently altered tumor suppressor genes were found in these regions, including PIK3CA, ERBB2, EP300 and FBXW7. CNA hotspots and related enriched functional categories were also identified. The incidence of chromothripsis in cervical cancer was estimated to be 6.06%, and the chromosome pulverization hotspot regions were detected. Based on the curated data, we developed CNAdbCC (http://cailab.labshare.cn/CNAdbCC/), a comprehensive database for copy number alterations in cervical cancer. We provide a user-friendly Web interface for data mining and visualization. It is the most comprehensive public database devoted exclusively to genomic alterations in cervical cancer. These results extend our molecular understanding of cervical cancer. The database will enable researchers to explore specific CNA patterns in this lethal cancer and facilitate the discovery of therapeutic candidates.


Assuntos
Biomarcadores Tumorais/genética , Variações do Número de Cópias de DNA , Genoma Humano , Estudo de Associação Genômica Ampla , Genômica/métodos , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Bases de Dados Genéticas , Feminino , Humanos
9.
BMC Genomics ; 19(1): 138, 2018 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-29433427

RESUMO

BACKGROUND: The integration of DNA methylation and copy number alteration data promises to provide valuable insight into the underlying molecular mechanisms responsible for cancer initiation and progression. However, the generation and processing of these datasets are costly and time-consuming if carried out separately. The Illumina Infinium HumanMethylation450 BeadChip, initially designed for the evaluation of DNA methylation levels, allows copy number variant calling using bioinformatics tools. RESULTS: A substantial amount of Infinium HumanMethylation450 data across various cancer types has been accumulated in recent years and is a valuable resource for large-scale data analysis. Here we present MethCNA, a comprehensive database for genomic and epigenomic data integration in human cancer. In the current release, MethCNA contains about 10,000 tumor samples representing 37 cancer types. All raw array data were collected from The Cancer Genome Atlas and NCBI Gene Expression Omnibus database and analyzed using a pipeline that integrated multiple computational resources and tools. The normalized copy number aberration data and DNA methylation alterations were obtained. We provide a user-friendly web-interface for data mining and visualization. CONCLUSIONS: The Illumina Infinium HumanMethylation450 BeadChip enables the interrogation and integration of both genomic and epigenomic data from exactly the same DNA specimen, and thus can aid in distinguishing driver from passenger mutations in cancer. We expect MethCNA will enable researchers to explore DNA methylation and copy number alteration patterns, identify key oncogenic drivers in cancer, and assist in the development of targeted therapies. MethCNA is publicly available online at http://cgma.scu.edu.cn/MethCNA .


Assuntos
Biologia Computacional/métodos , Bases de Dados Genéticas , Epigenômica/métodos , Genômica/métodos , Neoplasias/genética , Variações do Número de Cópias de DNA , Metilação de DNA , DNA de Neoplasias/genética , Perfilação da Expressão Gênica/métodos , Humanos , Internet , Neoplasias/classificação , Reprodutibilidade dos Testes
10.
Nucleic Acids Res ; 44(W1): W252-8, 2016 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-27185889

RESUMO

Chromothripsis is a recently observed phenomenon in cancer cells in which one or several chromosomes shatter into pieces with subsequent inaccurate reassembly and clonal propagation. This type of event generates a potentially vast number of mutations within a relatively short-time period, and has been considered as a new paradigm in cancer development. Despite recent advances, much work is still required to better understand the molecular mechanisms of this phenomenon, and thus an easy-to-use tool is in urgent need for automatically detecting and annotating chromothripsis. Here we present CTLPScanner, a web server for detection of chromothripsis-like pattern (CTLP) in genomic array data. The output interface presents intuitive graphical representations of detected chromosome pulverization region, as well as detailed results in table format. CTLPScanner also provides additional information for associated genes in chromothripsis region to help identify the potential candidates involved in tumorigenesis. To assist in performing meta-data analysis, we integrated over 50 000 pre-processed genomic arrays from The Cancer Genome Atlas and Gene Expression Omnibus into CTLPScanner. The server allows users to explore the presence of chromothripsis signatures from public data resources, without carrying out any local data processing. CTLPScanner is freely available at http://cgma.scu.edu.cn/CTLPScanner/.


Assuntos
Transformação Celular Neoplásica/genética , Cromossomos Humanos/química , Cromotripsia , Proteínas de Neoplasias/genética , Neoplasias/genética , Interface Usuário-Computador , Atlas como Assunto , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Mapeamento Cromossômico , Gráficos por Computador , Bases de Dados Genéticas , Humanos , Armazenamento e Recuperação da Informação , Internet , Taxa de Mutação , Proteínas de Neoplasias/metabolismo , Neoplasias/classificação , Neoplasias/patologia , Análise de Sequência com Séries de Oligonucleotídeos
11.
Bioinformatics ; 32(9): 1433-5, 2016 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-26722116

RESUMO

UNLABELLED: Chromothripsis is a single catastrophic event that can lead to massive genomic rearrangements confined to one or a few chromosomes. It provides an alternative paradigm in cancer development and changes the conventional view that cancer develops in a stepwise progression. The mechanisms underlying chromothripsis and their specific impact on tumorigenesis are still poorly understood, and further examination of a large number of identified chromothripsis samples is needed. Unfortunately, this data are difficult to access, as they are scattered across multiple publications, come in different formats and descriptions, or are hidden in figures and supplementary materials. To improve access to this data and promote meta-analysis, we developed ChromothripsisDB, a manually curated database containing a unified description of all published chromothripsis cases and relevant genomic aberrations. Currently, 423 chromothripsis samples representing 107 research articles are included in our database. ChromothripsisDB represents an extraordinary resource for mining the existing knowledge of chromothripsis, and will facilitate the identification of mechanisms involved in this phenomenon. AVAILABILITY AND IMPLEMENTATION: ChromothripsisDB is freely available at http://cgma.scu.edu.cn/ChromothripsisDB CONTACT: haoyang.cai@scu.edu.cn SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Aberrações Cromossômicas , Cromotripsia , Bases de Dados Factuais , Transformação Celular Neoplásica , Humanos
12.
Nucleic Acids Res ; 43(Database issue): D825-30, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25428357

RESUMO

Somatic copy number aberrations (CNA) represent a mutation type encountered in the majority of cancer genomes. Here, we present the 2014 edition of arrayMap (http://www.arraymap.org), a publicly accessible collection of pre-processed oncogenomic array data sets and CNA profiles, representing a vast range of human malignancies. Since the initial release, we have enhanced this resource both in content and especially with regard to data mining support. The 2014 release of arrayMap contains more than 64,000 genomic array data sets, representing about 250 tumor diagnoses. Data sets included in arrayMap have been assembled from public repositories as well as additional resources, and integrated by applying custom processing pipelines. Online tools have been upgraded for a more flexible array data visualization, including options for processing user provided, non-public data sets. Data integration has been improved by mapping to multiple editions of the human reference genome, with the majority of the data now being available for the UCSC hg18 as well as GRCh37 versions. The large amount of tumor CNA data in arrayMap can be freely downloaded by users to promote data mining projects, and to explore special events such as chromothripsis-like genome patterns.


Assuntos
Variações do Número de Cópias de DNA , Bases de Dados Genéticas , Neoplasias/genética , Análise de Sequência com Séries de Oligonucleotídeos , Mapeamento Cromossômico , Genoma , Humanos , Internet
13.
BMC Genomics ; 17(1): 799, 2016 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-27733115

RESUMO

BACKGROUND: DNA copy number profiles from microarray and sequencing experiments sometimes contain wave artefacts which may be introduced during sample preparation and cannot be removed completely by existing preprocessing methods. Besides, large derivative log ratio spread (DLRS) of the probes correlating with poor DNA quality is sometimes observed in genome screening experiments and may lead to unreliable copy number profiles. Depending on the extent of these artefacts and the resulting misidentification of copy number alterations/variations (CNA/CNV), it may be desirable to exclude such samples from analyses or to adapt the downstream data analysis strategy accordingly. RESULTS: Here, we propose a method to distinguish reliable genomic copy number profiles from those containing heavy wave artefacts and/or large DLRS. We define four features that adequately summarize the copy number profiles for reliability assessment, and train a classifier on a dataset of 1522 copy number profiles from various microarray platforms. The method can be applied to predict the reliability of copy number profiles irrespective of the underlying microarray platform and may be adapted for those sequencing platforms from which copy number estimates could be computed as a piecewise constant signal. Further details can be found at https://github.com/baudisgroup/CNARA . CONCLUSIONS: We have developed a method for the assessment of genomic copy number profiling data, and suggest to apply the method in addition to and after other state-of-the-art noise correction and quality control procedures. CNARA could be instrumental in improving the assessment of data used for genomic data mining experiments and support the reliable functional attribution of copy number aberrations especially in cancer research.


Assuntos
Biologia Computacional/métodos , Variações do Número de Cópias de DNA , Dosagem de Genes , Genômica/métodos , Algoritmos , Simulação por Computador , Reprodutibilidade dos Testes , Navegador
14.
Nucleic Acids Res ; 42(Database issue): D1055-62, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24225322

RESUMO

DNA copy number aberrations (CNAs) can be found in the majority of cancer genomes and are crucial for understanding the potential mechanisms underlying tumor initiation and progression. Since the first release in 2001, the Progenetix project (http://www.progenetix.org) has provided a reference resource dedicated to provide the most comprehensive collection of genome-wide CNA profiles. Reflecting the application of comparative genomic hybridization techniques to tens of thousands of cancer genomes, over the past 12 years our data curation efforts have resulted in a more than 60-fold increase in the number of cancer samples presented through Progenetix. In addition, new data exploration tools and visualization options have been added. In particular, the gene-specific CNA frequency analysis should facilitate the assignment of cancer genes to related cancer types. In addition, the new user file processing interface allows users to take advantage of the online tools, including various data representation options for proprietary data pre-publication. In this update article, we report recent improvements of the database in terms of content, user interface and online tools.


Assuntos
Variações do Número de Cópias de DNA , Bases de Dados de Ácidos Nucleicos , Neoplasias/genética , Animais , Frequência do Gene , Genoma Humano , Genômica , Humanos , Internet
15.
BMC Genomics ; 15: 82, 2014 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-24476156

RESUMO

BACKGROUND: Chromothripsis is a recently discovered phenomenon of genomic rearrangement, possibly arising during a single genome-shattering event. This could provide an alternative paradigm in cancer development, replacing the gradual accumulation of genomic changes with a "one-off" catastrophic event. However, the term has been used with varying operational definitions, with the minimal consensus being a large number of locally clustered copy number aberrations. The mechanisms underlying these chromothripsis-like patterns (CTLP) and their specific impact on tumorigenesis are still poorly understood. RESULTS: Here, we identified CTLP in 918 cancer samples, from a dataset of more than 22,000 oncogenomic arrays covering 132 cancer types. Fragmentation hotspots were found to be located on chromosome 8, 11, 12 and 17. Among the various cancer types, soft-tissue tumors exhibited particularly high CTLP frequencies. Genomic context analysis revealed that CTLP rearrangements frequently occurred in genomes that additionally harbored multiple copy number aberrations (CNAs). An investigation into the affected chromosomal regions showed a large proportion of arm-level pulverization and telomere related events, which would be compatible to a number of underlying mechanisms. We also report evidence that these genomic events may be correlated with patient age, stage and survival rate. CONCLUSIONS: Through a large-scale analysis of oncogenomic array data sets, this study characterized features associated with genomic aberrations patterns, compatible to the spectrum of "chromothripsis"-definitions as previously used. While quantifying clustered genomic copy number aberrations in cancer samples, our data indicates an underlying biological heterogeneity behind these chromothripsis-like patterns, beyond a well defined "chromthripsis" phenomenon.


Assuntos
Genoma Humano , Neoplasias/genética , Fatores Etários , Algoritmos , Transformação Celular Neoplásica/genética , Aberrações Cromossômicas , Análise por Conglomerados , Hibridização Genômica Comparativa , Variações do Número de Cópias de DNA , Humanos , Estadiamento de Neoplasias , Neoplasias/mortalidade , Neoplasias/patologia , Polimorfismo de Nucleotídeo Único , Curva ROC
16.
Front Bioeng Biotechnol ; 12: 1437426, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39081334

RESUMO

Studies on odontogenesis are of great importance to treat dental abnormalities and tooth loss. However, the odontogenesis process was poorly studied in humans, especially at the early developmental stages. Here, we combined RNA sequencing (RNA-seq) with Laser-capture microdissection (LCM) to establish a spatiotemporal transcriptomic investigation for human deciduous tooth germs at the crucial developmental stage to offer new perspectives to understand tooth development and instruct tooth regeneration. Several hallmark events, including angiogenesis, ossification, axonogenesis, and extracellular matrix (ECM) organization, were identified during odontogenesis in human dental epithelium and mesenchyme from the cap stage to the early bell stage. ECM played an essential role in the shift of tooth-inductive capability. Species comparisons demonstrated these hallmark events both in humans and mice. This study reveals the hallmark events during odontogenesis, enriching the transcriptomic research on human tooth development at the early stage.

17.
Stem Cell Reports ; 19(3): 399-413, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38428414

RESUMO

Degenerative bone disorders have a significant impact on global health, and regeneration of articular cartilage remains a challenge. Existing cell therapies using mesenchymal stromal cells (MSCs) have shown limited efficacy, highlighting the necessity for alternative stem cell sources. Here, we have identified and characterized MSX1+ mesenchymal progenitor cells in the developing limb bud with remarkable osteochondral-regenerative and microenvironment-adaptive capabilities. Single-cell sequencing further revealed the presence of two major cell compositions within the MSX1+ cells, where a distinct PDGFRAlow subset retained the strongest osteochondral competency and could efficiently regenerate articular cartilage in vivo. Furthermore, a strategy was developed to generate MSX1+PDGFRAlow limb mesenchyme-like (LML) cells from human pluripotent stem cells that closely resembled their mouse counterparts, which were bipotential in vitro and could directly regenerate damaged cartilage in a mouse injury model. Together, our results indicated that MSX1+PDGFRAlow LML cells might be a prominent stem cell source for human cartilage regeneration.


Assuntos
Cartilagem Articular , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Humanos , Camundongos , Animais , Células-Tronco , Terapia Baseada em Transplante de Células e Tecidos , Mesoderma , Transplante de Células-Tronco Mesenquimais/métodos , Diferenciação Celular , Fator de Transcrição MSX1/genética
18.
Front Genet ; 14: 1246983, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38075691

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal lung disease that poses a significant challenge to medical professionals due to its increasing incidence and prevalence coupled with the limited understanding of its underlying molecular mechanisms. In this study, we employed a novel approach by integrating five expression datasets from bulk tissue with single-cell datasets; they underwent pseudotime trajectory analysis, switch gene selection, and cell communication analysis. Utilizing the prognostic information derived from the GSE47460 dataset, we identified 22 differentially expressed switch genes that were correlated with clinical indicators as important genes. Among these genes, we found that the midkine (MDK) gene has the potential to serve as a marker of Idiopathic pulmonary fibrosis because its cellular communicating genes are differentially expressed in the epithelial cells. We then utilized midkine and its cellular communication-related genes to calculate the midkine score. Machine learning models were further constructed through midkine and related genes to predict Idiopathic pulmonary fibrosis disease through the bulk gene expression datasets. The midkine score demonstrated a correlation with clinical indexes, and the machine learning model achieved an AUC of 0.94 and 0.86 in the Idiopathic pulmonary fibrosis classification task based on lung tissue samples and peripheral blood mononuclear cell samples, respectively. Our findings offer valuable insights into the pathogenesis of Idiopathic pulmonary fibrosis, providing new therapeutic directions and target genes for further investigation.

19.
Med Oncol ; 40(2): 78, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36635412

RESUMO

Cervical cancer is a heterogeneous malignancy mainly caused by human papillomavirus (HPV). While a few studies have revealed heterogeneity of cervical cancer in chromosome levels, the correlation between genetic heterogeneity and HPV integration in cervical cancer remains unknown. Here, we applied multi-region whole-exome sequencing and HPV integration analysis to explore intratumor heterogeneity in cervical cancer. We sequenced 20 tumor regions and 5 adjacent normal tissues from 5 cervical cancer patients, analysis based on somatic mutations and somatic copy number alterations (SCNAs) levels were performed. Variable heterogeneity was observed between the five patients with different tumor stages and HPV infection statuses. We found HPV integration has a positive effect on somatic mutation burden, but the relation to SCNAs remains unclear. Frequently mutated genes in cervical cancer were identified as trunk events, such as FBXW7, PIK3CA, FAT1 in somatic mutations and TP63, MECOM, PIK3CA, TBL1XR1 in SCNAs. New potential driver genes in cervical cancer were summarized including POU2F2, TCF7 and UBE2A. The SCNAs level has potential relation with tumor stage, and Signature 3 related to homologous recombination deficiency may be the appropriate biomarker in advanced cervical cancer. Mutation signature analysis also revealed a potential pattern that APOBEC-associated signature occurs in early stage and signatures associated with DNA damage repair arise at the later stage of cervical cancer evolution. In a conclusion, our study provides insights into the potential relationship between HPV infection and tumor heterogeneity. Those results enhanced our understanding of tumorigenesis and progression in cervical cancer.


Assuntos
Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Classe I de Fosfatidilinositol 3-Quinases/genética , Evolução Clonal/genética , Variações do Número de Cópias de DNA , Mutação , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/virologia
20.
Theranostics ; 13(4): 1443-1453, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36923532

RESUMO

Background: Chromothripsis caused massive, clustered genomic rearrangements is prevalent in cancer and is considered a new paradigm for tumorigenesis and progression. In this study, we investigated the association among chromothripsis, anti-tumor immune responses, and responsiveness to immune checkpoint blockade (ICB). Methods: Quantification of immune cell infiltration and functional enrichment of immune-related signaling pathways were performed in the discovery set (n = 9403) and the validation set (n = 1140). we investigated the association between chromothripsis and anti-tumor immune responses. In the immunotherapy cohort, copy number alteration-based chromothripsis scores (CPSs) were introduced to assess the extent of chromothripsis to evaluate its association with responsiveness to ICB. Results: In the discovery set and the validation set, the ratios of CD8+ T cells to Tregs, TAMs, and MDSCs were significantly lower in tumors with chromothripsis (P = 1.5 × 10-13, P = 5.4 × 10-8, and P = 1.2 × 10-4, respectively, TCGA; P = 1.0 × 10-13, P = 3.6 × 10-15, and P = 3.3 × 10-3, respectively, PCAWG). The relevant pathways underlying the antitumor immune effect were significantly enriched in tumors without chromothripsis. Chromothripsis can be used as an independent predictor, and patients with low-CPSs experienced longer overall survival (OS) after immunotherapy [HR, 1.90; 95% confidence interval, 1.10-3.28; P = 0.019]. Conclusions: Our findings highlight the reduced cytotoxic immune infiltration in tumors with chromothripsis and enhanced immunosuppression in the tumor microenvironment. Chromothripsis can thus be used as a potential indicator to help identify patients who will respond to ICB, which could complement established biomarkers.


Assuntos
Antineoplásicos , Cromotripsia , Neoplasias , Humanos , Linfócitos T CD8-Positivos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/genética , Imunoterapia , Microambiente Tumoral
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