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1.
BJOG ; 2024 Aug 05.
Article de Anglais | MEDLINE | ID: mdl-39099410

RÉSUMÉ

OBJECTIVE: To analyse the global burden, trends and cross-country inequalities of female breast and gynaecologic cancers (FeBGCs). DESIGN: Population-Based Study. SETTING: Data sourced from the Global Burden of Disease Study 2019. POPULATION: Individuals diagnosed with FeBGCs. METHODS: Age-standardised mortality rates (ASMRs), age-standardised Disability-Adjusted Life Years (DALYs) rates (ASDRs) and their 95% uncertainty interval (UI) described the burden. Estimated annual percentage changes (EAPCs) and their confidence interval (CI) of age-standardised rates (ASRs) illustrated trends. Social inequalities were quantified using the Slope Index of Inequality (SII) and Concentration Index. MAIN OUTCOME MEASURES: The main outcome measures were the burden of FeBGCs and the trends in its inequalities over time. RESULTS: In 2019, the ASDRs per 100 000 females were as follows: breast cancer: 473.83 (95% UI: 437.30-510.51), cervical cancer: 210.64 (95% UI: 177.67-234.85), ovarian cancer: 124.68 (95% UI: 109.13-138.67) and uterine cancer: 210.64 (95% UI: 177.67-234.85). The trends per year from 1990 to 2019 were expressed as EAPCs of ASDRs and these: for Breast cancer: -0.51 (95% CI: -0.57 to -0.45); Cervical cancer: -0.95 (95% CI: -0.99 to -0.89); Ovarian cancer: -0.08 (95% CI: -0.12 to -0.04); and Uterine cancer: -0.84 (95% CI: -0.93 to -0.75). In the Social Inequalities Analysis (1990-2019) the SII changed from 689.26 to 607.08 for Breast, from -226.66 to -239.92 for cervical, from 222.45 to 228.83 for ovarian and from 74.61 to 103.58 for uterine cancer. The concentration index values ranged from 0.2 to 0.4. CONCLUSIONS: The burden of FeBGCs worldwide showed a downward trend from 1990 to 2019. Countries or regions with higher Socio-demographic Index (SDI) bear a higher DALYs burden of breast, ovarian and uterine cancers, while those with lower SDI bear a heavier burden of cervical cancer. These inequalities increased over time.

2.
Article de Anglais | MEDLINE | ID: mdl-39196711

RÉSUMÉ

Methamphetamine (METH) is a highly addictive psychostimulant that causes physical and psychological damage and immune system disorder, especially in the liver that contains a significant number of immune cells. Dopamine, a key neurotransmitter in METH addiction and immune regulation, plays a crucial role in this process. Here, we developed a chronic METH administration model and conducted single-cell RNA sequencing (scRNA-seq) to investigate the effect of METH on liver immune cells and involvement of dopamine receptor D1 (DRD1). Our findings reveal that chronic exposure to METH induces immune cell identity shifts from Ifitm3+Macrophage (Mac) and Ccl5+Mac to Cd14+Mac, and from Fyn+CD4+T effector (Teff), CD8+T, and natural killer T cells (NKT) to Fos+CD4+T and Rora+ group 2 innate lymphoid cells (ILC2), along with suppression of multiple functional immune pathways. DRD1 is implicated in regulating certain pathways and identity shifts among the hepatic immune cells. Our results provide valuable insights into development of targeted therapies to mitigate METH-induced immune impairment.

3.
Mol Ther Nucleic Acids ; 35(1): 102158, 2024 Mar 12.
Article de Anglais | MEDLINE | ID: mdl-38439912

RÉSUMÉ

Male infertility has emerged as a global issue, partly attributed to psychological stress. However, the cellular and molecular mechanisms underlying the adverse effects of psychological stress on male reproductive function remain elusive. We created a psychologically stressed model using terrified-sound and profiled the testes from stressed and control rats using single-cell RNA sequencing. Comparative and comprehensive transcriptome analyses of 11,744 testicular cells depicted the cellular landscape of spermatogenesis and revealed significant molecular alterations of spermatogenesis suffering from psychological stress. At the cellular level, stressed rats exhibited delayed spermatogenesis at the spermatogonia and pachytene phases, resulting in reduced sperm production. Additionally, psychological stress rewired cellular interactions among germ cells, negatively impacting reproductive development. Molecularly, we observed the down-regulation of anti-oxidation-related genes and up-regulation of genes promoting reactive oxygen species (ROS) generation in the stress group. These alterations led to elevated ROS levels in testes, affecting the expression of key regulators such as ATF2 and STAR, which caused reproductive damage through apoptosis or inhibition of testosterone synthesis. Overall, our study aimed to uncover the cellular and molecular mechanisms by which psychological stress disrupts spermatogenesis, offering insights into the mechanisms of psychological stress-induced male infertility in other species and promises in potential therapeutic targets.

4.
Brief Bioinform ; 24(6)2023 09 22.
Article de Anglais | MEDLINE | ID: mdl-37903416

RÉSUMÉ

The emergence of single-cell RNA sequencing (scRNA-seq) technology has revolutionized the identification of cell types and the study of cellular states at a single-cell level. Despite its significant potential, scRNA-seq data analysis is plagued by the issue of missing values. Many existing imputation methods rely on simplistic data distribution assumptions while ignoring the intrinsic gene expression distribution specific to cells. This work presents a novel deep-learning model, named scMultiGAN, for scRNA-seq imputation, which utilizes multiple collaborative generative adversarial networks (GAN). Unlike traditional GAN-based imputation methods that generate missing values based on random noises, scMultiGAN employs a two-stage training process and utilizes multiple GANs to achieve cell-specific imputation. Experimental results show the efficacy of scMultiGAN in imputation accuracy, cell clustering, differential gene expression analysis and trajectory analysis, significantly outperforming existing state-of-the-art techniques. Additionally, scMultiGAN is scalable to large scRNA-seq datasets and consistently performs well across sequencing platforms. The scMultiGAN code is freely available at https://github.com/Galaxy8172/scMultiGAN.


Sujet(s)
Analyse sur cellule unique , Transcriptome , Analyse sur cellule unique/méthodes , Analyse de regroupements , , Analyse de données , Analyse de séquence d'ARN , Analyse de profil d'expression de gènes
7.
Front Oncol ; 12: 933210, 2022.
Article de Anglais | MEDLINE | ID: mdl-35875102

RÉSUMÉ

Necroptosis is a programmed form of necrotic cell death in regulating cancer ontogenesis, progression, and tumor microenvironment (TME) and could drive tumor-infiltrating cells to release pro-inflammatory cytokines, incurring strong immune responses. Nowadays, there are few identified biomarkers applied in clinical immunotherapy, and it is increasingly recognized that high levels of tumor necroptosis could enhance the response to immunotherapy. However, comprehensive characterization of necroptosis associated with TME and immunotherapy in Hepatocellular carcinoma (HCC) remains unexplored. Here, we computationally characterized necroptosis landscape in HCC samples from TCGA and ICGA cohorts and stratified them into two necroptosis clusters (A or B) with significantly different characteristics in clinical prognosis, immune cell function, and TME-landscapes. Additionally, to further evaluate the necroptosis levels of each sample, we established a novel necroptosis-related gene score (NRGscore). We further investigated the TME, tumor mutational burden (TMB), clinical response to immunotherapy, and chemotherapeutic drug sensitivity of HCC subgroups stratified by the necroptosis landscapes. The NRGscore is robust and highly predictive of HCC clinical outcomes. Further analysis indicated that the high NRGscore group resembles the immune-inflamed phenotype while the low score group is analogous to the immune-exclusion or metabolism phenotype. Additionally, the high NRGscore group is more sensitive to immune checkpoint blockade-based immunotherapy, which was further validated using an external HCC cohort, metastatic melanoma cohort, and advanced urothelial cancer cohort. Besides, the NRGscore was demonstrated as a potential biomarker for chemotherapy, wherein the high NRGscore patients with more tumor stem cell composition could be more sensitive to Cisplatin, Doxorubicin, Paclitaxel-based chemotherapy, and Sorafenib therapy. Collectively, a comprehensive characterization of the necroptosis in HCC suggested its implications for predicting immune infiltration and response to immunotherapy of HCC, providing promising strategies for treatment.

8.
Front Immunol ; 13: 890150, 2022.
Article de Anglais | MEDLINE | ID: mdl-35686121

RÉSUMÉ

As the most common type of renal cell carcinoma (RCC), the renal clear cell carcinoma (ccRCC) is highly malignant and insensitive to chemotherapy or radiotherapy. Although systemic immunotherapies have been successfully applied to ccRCC in recent years, screening for patients who can benefit most from these therapies is still essential and challenging due to immunological heterogeneity of ccRCC patients. To this end, we implemented a series of deep investigation on the expression and clinic data of ccRCC from The Cancer Genome Atlas (TCGA) International Consortium for Cancer Genomics (ICGC). We identified a total of 946 immune-related genes that were differentially expressed. Among them, five independent genes, including SHC1, WNT5A, NRP1, TGFA, and IL4R, were significantly associated with survival and used to construct the immune-related prognostic differential gene signature (IRPDGs). Then the ccRCC patients were categorized into high-risk and low-risk subgroups based on the median risk score of the IRPDGs. IRPDGs subgroups displays distinct genomic and immunological characteristics. Known immunotherapy-related genes show different mutation burden, wherein the mutation rate of VHL was higher than 40% in the two IRPDGs subgroups, and SETD2 and BAP1 mutations differed most between two groups with higher frequency in the high-risk subgroup. Moreover, IRPDGs subgroups had different abundance in tumor-infiltrating immune cells (TIICs) with distinct immunotherapy efficacy. Plasma cells, regulatory cells (Tregs), follicular helper T cells (Tfh), and M0 macrophages were enriched in the high-risk group with a higher tumor immune dysfunction and rejection (TIDE) score. In contrast, the low-risk group had abundant M1 macrophages, mast cell resting and dendritic cell resting infiltrates with lower TIDE score and benefited more from immune checkpoint inhibitors (ICI) treatment. Compared with other biomarkers, such as TIDE and tumor inflammatory signatures (TIS), IRPDGs demonstrated to be a better biomarker for assessing the prognosis of ccRCC and the efficacy of ICI treatment with the promise in screening precise patients for specific immunotherapies.


Sujet(s)
Néphrocarcinome , Tumeurs du rein , Marqueurs biologiques , Néphrocarcinome/diagnostic , Néphrocarcinome/génétique , Néphrocarcinome/thérapie , Humains , Immunothérapie , Tumeurs du rein/diagnostic , Tumeurs du rein/génétique , Tumeurs du rein/thérapie , Pronostic
11.
Brief Bioinform ; 23(1)2022 01 17.
Article de Anglais | MEDLINE | ID: mdl-34791021

RÉSUMÉ

The innovation of biotechnologies has allowed the accumulation of omics data at an alarming rate, thus introducing the era of 'big data'. Extracting inherent valuable knowledge from various omics data remains a daunting problem in bioinformatics. Better solutions often need some kind of more innovative methods for efficient handlings and effective results. Recent advancements in integrated analysis and computational modeling of multi-omics data helped address such needs in an increasingly harmonious manner. The development and application of machine learning have largely advanced our insights into biology and biomedicine and greatly promoted the development of therapeutic strategies, especially for precision medicine. Here, we propose a comprehensive survey and discussion on what happened, is happening and will happen when machine learning meets omics. Specifically, we describe how artificial intelligence can be applied to omics studies and review recent advancements at the interface between machine learning and the ever-widest range of omics including genomics, transcriptomics, proteomics, metabolomics, radiomics, as well as those at the single-cell resolution. We also discuss and provide a synthesis of ideas, new insights, current challenges and perspectives of machine learning in omics.


Sujet(s)
Intelligence artificielle , Apprentissage machine , Biologie informatique/méthodes , Génomique/méthodes , Protéomique/méthodes
12.
Am J Hum Genet ; 107(3): 461-472, 2020 09 03.
Article de Anglais | MEDLINE | ID: mdl-32781045

RÉSUMÉ

RNA sequencing (RNA-seq) is a powerful technology for studying human transcriptome variation. We introduce PAIRADISE (Paired Replicate Analysis of Allelic Differential Splicing Events), a method for detecting allele-specific alternative splicing (ASAS) from RNA-seq data. Unlike conventional approaches that detect ASAS events one sample at a time, PAIRADISE aggregates ASAS signals across multiple individuals in a population. By treating the two alleles of an individual as paired, and multiple individuals sharing a heterozygous SNP as replicates, we formulate ASAS detection using PAIRADISE as a statistical problem for identifying differential alternative splicing from RNA-seq data with paired replicates. PAIRADISE outperforms alternative statistical models in simulation studies. Applying PAIRADISE to replicate RNA-seq data of a single individual and to population-scale RNA-seq data across many individuals, we detect ASAS events associated with genome-wide association study (GWAS) signals of complex traits or diseases. Additionally, PAIRADISE ASAS analysis detects the effects of rare variants on alternative splicing. PAIRADISE provides a useful computational tool for elucidating the genetic variation and phenotypic association of alternative splicing in populations.


Sujet(s)
Épissage alternatif/génétique , Prédisposition génétique à une maladie , Hérédité multifactorielle/génétique , Transcriptome/génétique , Allèles , Femelle , Analyse de profil d'expression de gènes , Génétique des populations/méthodes , Étude d'association pangénomique , Séquençage nucléotidique à haut débit , Humains , Mâle , Modèles statistiques , RNA-Seq ,
13.
Nucleic Acids Res ; 48(15): e85, 2020 09 04.
Article de Anglais | MEDLINE | ID: mdl-32588900

RÉSUMÉ

Single-cell RNA-sequencing (scRNA-seq) enables the characterization of transcriptomic profiles at the single-cell resolution with increasingly high throughput. However, it suffers from many sources of technical noises, including insufficient mRNA molecules that lead to excess false zero values, termed dropouts. Computational approaches have been proposed to recover the biologically meaningful expression by borrowing information from similar cells in the observed dataset. However, these methods suffer from oversmoothing and removal of natural cell-to-cell stochasticity in gene expression. Here, we propose the generative adversarial networks (GANs) for scRNA-seq imputation (scIGANs), which uses generated cells rather than observed cells to avoid these limitations and balances the performance between major and rare cell populations. Evaluations based on a variety of simulated and real scRNA-seq datasets show that scIGANs is effective for dropout imputation and enhances various downstream analysis. ScIGANs is robust to small datasets that have very few genes with low expression and/or cell-to-cell variance. ScIGANs works equally well on datasets from different scRNA-seq protocols and is scalable to datasets with over 100 000 cells. We demonstrated in many ways with compelling evidence that scIGANs is not only an application of GANs in omics data but also represents a competing imputation method for the scRNA-seq data.


Sujet(s)
RNA-Seq/méthodes , Analyse sur cellule unique/méthodes , Logiciel , Transcriptome/génétique , Biologie informatique , ARN/génétique , ARN messager/génétique , /méthodes
14.
Gene ; 715: 144012, 2019 Oct 05.
Article de Anglais | MEDLINE | ID: mdl-31357021

RÉSUMÉ

Long noncoding RNAs (lncRNAs) have been shown to play an important role in tumor biogenesis and prognosis. The glioma is a grade classified cancer, however, we still lack the knowledge on their function during glioma progression. While previous studies have shown how lncRNAs regulate protein-coding gene epigenetically, it is still unclear how lncRNAs are regulated epigenetically. In this study, we firstly analyzed the RNA-seq data systematically across grades II, IV, and IV of glioma samples. We identified 60 lncRNAs that are significantly differentially expressed over disease progression (DElncRNA), including well-known PVT1, HOTAIR, H19 and rarely studied CARD8-AS, MIR4435-2HG. Secondly, by integrating HM450K methylation microarray data, we demonstrated that some of the lncRNAs are epigenetically regulated by methylation. Thirdly, we developed a DESeq2-GSEA-ceRNA-survival analysis strategy to investigate their functions. Particularly, MIR4435-2HG is highly expressed in high-grade glioma and may have an impact on EMT and TNFα signaling pathway by functioning as a miRNA sponge of miR-125a-5p and miR-125b-5p to increase the expression of CD44. Our results revealed the dynamic expression of lncRNAs in glioma progression and their epigenetic regulation mechanism.


Sujet(s)
Méthylation de l'ADN , ADN tumoral , Épigenèse génétique , Régulation de l'expression des gènes tumoraux , Gliome , microARN , ARN long non codant , ARN tumoral , ADN tumoral/génétique , ADN tumoral/métabolisme , Analyse de profil d'expression de gènes , Gliome/génétique , Gliome/métabolisme , Gliome/anatomopathologie , Humains , microARN/biosynthèse , microARN/génétique , Protéines tumorales/biosynthèse , Protéines tumorales/génétique , ARN long non codant/biosynthèse , ARN long non codant/génétique , ARN tumoral/biosynthèse , ARN tumoral/génétique
15.
Front Genet ; 9: 410, 2018.
Article de Anglais | MEDLINE | ID: mdl-30319691

RÉSUMÉ

Alzheimer's disease (AD) is the most common cause of dementia. Although genome-wide association study (GWAS) have reported hundreds of single-nucleotide polymorphisms (SNPs) and genes linked to AD, the mechanisms about how these SNPs modulate the development of AD remain largely unknown. In this study, we performed GWAS for three traits in cerebrospinal fluid (CSF) and one clinical trait in the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort. Our analysis identified five most significant AD related SNPs (FDR < 0.05) within or proximal to APOE, APOC1, and TOMM40. One of the SNPs was co-inherited with APOE allele 4, which is the most important genetic risk factor for AD. Three of the five SNPs were located in promoter or enhancer regions, and transcription factor (TF) binding affinity calculations showed dramatic changes (| Log2FC| > 2) of three TFs (PLAG1, RREB1, and ZBTB33) for two motifs containing SNPs rs2075650 and rs157580. In addition, our GWAS showed that both rs2075650 and rs157580 were significantly associated with the poliovirus receptor-related 2 (PVRL2) gene (FDR < 0.25), which is involved in spreading of herpes simplex virus (HSV). The altered regulation of PVRL2 may increase the susceptibility AD patients to HSV and other virus infections of the brain. Our work suggests that AD is a type of immune disorder driven by viral or microbial infections of the brain during aging.

16.
Genome Biol ; 19(1): 133, 2018 09 14.
Article de Anglais | MEDLINE | ID: mdl-30217220

RÉSUMÉ

BACKGROUND: Understanding the embryonic stem cell (ESC) fate decision between self-renewal and proper differentiation is important for developmental biology and regenerative medicine. Attention has focused on mechanisms involving histone modifications, alternative pre-messenger RNA splicing, and cell-cycle progression. However, their intricate interrelations and joint contributions to ESC fate decision remain unclear. RESULTS: We analyze the transcriptomes and epigenomes of human ESC and five types of differentiated cells. We identify thousands of alternatively spliced exons and reveal their development and lineage-dependent characterizations. Several histone modifications show dynamic changes in alternatively spliced exons and three are strongly associated with 52.8% of alternative splicing events upon hESC differentiation. The histone modification-associated alternatively spliced genes predominantly function in G2/M phases and ATM/ATR-mediated DNA damage response pathway for cell differentiation, whereas other alternatively spliced genes are enriched in the G1 phase and pathways for self-renewal. These results imply a potential epigenetic mechanism by which some histone modifications contribute to ESC fate decision through the regulation of alternative splicing in specific pathways and cell-cycle genes. Supported by experimental validations and extended datasets from Roadmap/ENCODE projects, we exemplify this mechanism by a cell-cycle-related transcription factor, PBX1, which regulates the pluripotency regulatory network by binding to NANOG. We suggest that the isoform switch from PBX1a to PBX1b links H3K36me3 to hESC fate determination through the PSIP1/SRSF1 adaptor, which results in the exon skipping of PBX1. CONCLUSION: We reveal the mechanism by which alternative splicing links histone modifications to stem cell fate decision.


Sujet(s)
Épissage alternatif , Cellules souches embryonnaires/métabolisme , Code histone , Différenciation cellulaire , Division cellulaire , Cellules souches embryonnaires/cytologie , Exons , Phase G2 , Humains , Facteur de transcription-1 de la leucémie pré-B/génétique , Facteur de transcription-1 de la leucémie pré-B/métabolisme
17.
Methods Mol Biol ; 1754: 327-374, 2018.
Article de Anglais | MEDLINE | ID: mdl-29536452

RÉSUMÉ

Single-cell sequencing interrogates the sequence or chromatin information from individual cells with advanced next-generation sequencing technologies. It provides a higher resolution of cellular differences and a better understanding of the underlying genetic and epigenetic mechanisms of an individual cell in the context of its survival and adaptation to microenvironment. However, it is more challenging to perform single-cell sequencing and downstream data analysis, owing to the minimal amount of starting materials, sample loss, and contamination. In addition, due to the picogram level of the amount of nucleic acids used, heavy amplification is often needed during sample preparation of single-cell sequencing, resulting in the uneven coverage, noise, and inaccurate quantification of sequencing data. All these unique properties raise challenges in and thus high demands for computational methods that specifically fit single-cell sequencing data. We here comprehensively survey the current strategies and challenges for multiple single-cell sequencing, including single-cell transcriptome, genome, and epigenome, beginning with a brief introduction to multiple sequencing techniques for single cells.


Sujet(s)
Génomique/méthodes , Séquençage nucléotidique à haut débit/méthodes , Analyse de séquence d'ADN/méthodes , Analyse de séquence d'ARN/méthodes , Analyse sur cellule unique/méthodes , Séparation cellulaire/instrumentation , Séparation cellulaire/méthodes , Épigenèse génétique/génétique , Cytométrie en flux/instrumentation , Cytométrie en flux/méthodes , Génomique/instrumentation , Séquençage nucléotidique à haut débit/instrumentation , Humains , Microdissection au laser/instrumentation , Microdissection au laser/méthodes , Techniques d'analyse microfluidique/instrumentation , Techniques d'analyse microfluidique/méthodes , Polymorphisme de nucléotide simple/génétique , ARN/génétique , Analyse de séquence d'ADN/instrumentation , Analyse de séquence d'ARN/instrumentation , Analyse sur cellule unique/instrumentation , Transcriptome/génétique
18.
Nucleic Acids Res ; 45(21): 12100-12112, 2017 Dec 01.
Article de Anglais | MEDLINE | ID: mdl-29036709

RÉSUMÉ

Alternative splicing (AS) is a genetically and epigenetically regulated pre-mRNA processing to increase transcriptome and proteome diversity. Comprehensively decoding these regulatory mechanisms holds promise in getting deeper insights into a variety of biological contexts involving in AS, such as development and diseases. We assembled splicing (epi)genetic code, DeepCode, for human embryonic stem cell (hESC) differentiation by integrating heterogeneous features of genomic sequences, 16 histone modifications with a multi-label deep neural network. With the advantages of epigenetic features, DeepCode significantly improves the performance in predicting the splicing patterns and their changes during hESC differentiation. Meanwhile, DeepCode reveals the superiority of epigenomic features and their dominant roles in decoding AS patterns, highlighting the necessity of including the epigenetic properties when assembling a more comprehensive splicing code. Moreover, DeepCode allows the robust predictions across cell lineages and datasets. Especially, we identified a putative H3K36me3-regulated AS event leading to a nonsense-mediated mRNA decay of BARD1. Reduced BARD1 expression results in the attenuation of ATM/ATR signalling activities and further the hESC differentiation. These results suggest a novel candidate mechanism linking histone modifications to hESC fate decision. In addition, when trained in different contexts, DeepCode can be expanded to a variety of biological and biomedical fields.


Sujet(s)
Épissage alternatif , Cellules souches embryonnaires/métabolisme , Épigenèse génétique , Code histone , Apprentissage machine , , Différenciation cellulaire/génétique , Lignée cellulaire , Lignage cellulaire , Séquençage nucléotidique à haut débit , Humains , Analyse de séquence d'ARN , Protéines suppresseurs de tumeurs/génétique , Protéines suppresseurs de tumeurs/métabolisme , Ubiquitin-protein ligases/génétique , Ubiquitin-protein ligases/métabolisme
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