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1.
Brief Bioinform ; 25(4)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38877887

RESUMO

Neurodegenerative diseases, such as Alzheimer's disease, pose a significant global health challenge with their complex etiology and elusive biomarkers. In this study, we developed the Alzheimer's Identification Tool (AITeQ) using ribonucleic acid-sequencing (RNA-seq), a machine learning (ML) model based on an optimized ensemble algorithm for the identification of Alzheimer's from RNA-seq data. Analysis of RNA-seq data from several studies identified 87 differentially expressed genes. This was followed by a ML protocol involving feature selection, model training, performance evaluation, and hyperparameter tuning. The feature selection process undertaken in this study, employing a combination of four different methodologies, culminated in the identification of a compact yet impactful set of five genes. Twelve diverse ML models were trained and tested using these five genes (CNKSR1, EPHA2, CLSPN, OLFML3, and TARBP1). Performance metrics, including precision, recall, F1 score, accuracy, Matthew's correlation coefficient, and receiver operating characteristic area under the curve were assessed for the finally selected model. Overall, the ensemble model consisting of logistic regression, naive Bayes classifier, and support vector machine with optimized hyperparameters was identified as the best and was used to develop AITeQ. AITeQ is available at: https://github.com/ishtiaque-ahammad/AITeQ.


Assuntos
Doença de Alzheimer , Aprendizado de Máquina , Doença de Alzheimer/genética , Humanos , Algoritmos , Perfilação da Expressão Gênica/métodos , Transcriptoma , Biologia Computacional/métodos , RNA-Seq/métodos
2.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38739758

RESUMO

The complicated process of neuronal development is initiated early in life, with the genetic mechanisms governing this process yet to be fully elucidated. Single-cell RNA sequencing (scRNA-seq) is a potent instrument for pinpointing biomarkers that exhibit differential expression across various cell types and developmental stages. By employing scRNA-seq on human embryonic stem cells, we aim to identify differentially expressed genes (DEGs) crucial for early-stage neuronal development. Our focus extends beyond simply identifying DEGs. We strive to investigate the functional roles of these genes through enrichment analysis and construct gene regulatory networks to understand their interactions. Ultimately, this comprehensive approach aspires to illuminate the molecular mechanisms and transcriptional dynamics governing early human brain development. By uncovering potential links between these DEGs and intelligence, mental disorders, and neurodevelopmental disorders, we hope to shed light on human neurological health and disease. In this study, we have used scRNA-seq to identify DEGs involved in early-stage neuronal development in hESCs. The scRNA-seq data, collected on days 26 (D26) and 54 (D54), of the in vitro differentiation of hESCs to neurons were analyzed. Our analysis identified 539 DEGs between D26 and D54. Functional enrichment of those DEG biomarkers indicated that the up-regulated DEGs participated in neurogenesis, while the down-regulated DEGs were linked to synapse regulation. The Reactome pathway analysis revealed that down-regulated DEGs were involved in the interactions between proteins located in synapse pathways. We also discovered interactions between DEGs and miRNA, transcriptional factors (TFs) and DEGs, and between TF and miRNA. Our study identified 20 significant transcription factors, shedding light on early brain development genetics. The identified DEGs and gene regulatory networks are valuable resources for future research into human brain development and neurodevelopmental disorders.


Assuntos
Biomarcadores , Encéfalo , Redes Reguladoras de Genes , Células-Tronco Embrionárias Humanas , Análise de Célula Única , Humanos , Análise de Célula Única/métodos , Células-Tronco Embrionárias Humanas/metabolismo , Células-Tronco Embrionárias Humanas/citologia , Encéfalo/metabolismo , Encéfalo/embriologia , Encéfalo/citologia , Biomarcadores/metabolismo , Neurônios/metabolismo , Neurônios/citologia , Diferenciação Celular/genética , RNA-Seq , Neurogênese/genética , Regulação da Expressão Gênica no Desenvolvimento , Perfilação da Expressão Gênica , Análise de Sequência de RNA/métodos , Análise da Expressão Gênica de Célula Única
3.
Brief Bioinform ; 24(2)2023 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-36736372

RESUMO

Liver cancer is the third leading cause of cancer-related death worldwide, and hepatocellular carcinoma (HCC) accounts for a relatively large proportion of all primary liver malignancies. Among the several known risk factors, hepatitis B virus (HBV) infection is one of the important causes of HCC. In this study, we demonstrated that the HBV-infected HCC patients could be robustly classified into three clinically relevant subgroups, i.e. Cluster1, Cluster2 and Cluster3, based on consistent differentially expressed mRNAs and proteins, which showed better generalization. The proposed three subgroups showed different molecular characteristics, immune microenvironment and prognostic survival characteristics. The Cluster1 subgroup had near-normal levels of metabolism-related proteins, low proliferation activity and good immune infiltration, which were associated with its good liver function, smaller tumor size, good prognosis, low alpha-fetoprotein (AFP) levels and lower clinical stage. In contrast, the Cluster3 subgroup had the lowest levels of metabolism-related proteins, which corresponded with its severe liver dysfunction. Also, high proliferation activity and poor immune microenvironment in Cluster3 subgroup were associated with its poor prognosis, larger tumor size, high AFP levels, high incidence of tumor thrombus and higher clinical stage. The characteristics of the Cluster2 subgroup were between the Cluster1 and Cluster3 groups. In addition, MCM2-7, RFC2-5, MSH2, MSH6, SMC2, SMC4, NCPAG and TOP2A proteins were significantly upregulated in the Cluster3 subgroup. Meanwhile, abnormally high phosphorylation levels of these proteins were associated with high levels of DNA repair, telomere maintenance and proliferative features. Therefore, these proteins could be identified as potential diagnostic and prognostic markers. In general, our research provided a novel analytical protocol and insights for the robust classification, treatment and prevention of HBV-infected HCC.


Assuntos
Carcinoma Hepatocelular , Hepatite B , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Vírus da Hepatite B/metabolismo , Neoplasias Hepáticas/patologia , alfa-Fetoproteínas/metabolismo , Hepatite B/complicações , Microambiente Tumoral
4.
Brief Bioinform ; 24(1)2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36472568

RESUMO

Accounting for cell type compositions has been very successful at analyzing high-throughput data from heterogeneous tissues. Differential gene expression analysis at cell type level is becoming increasingly popular, yielding biomarker discovery in a finer granularity within a particular cell type. Although several computational methods have been developed to identify cell type-specific differentially expressed genes (csDEG) from RNA-seq data, a systematic evaluation is yet to be performed. Here, we thoroughly benchmark six recently published methods: CellDMC, CARseq, TOAST, LRCDE, CeDAR and TCA, together with two classical methods, csSAM and DESeq2, for a comprehensive comparison. We aim to systematically evaluate the performance of popular csDEG detection methods and provide guidance to researchers. In simulation studies, we benchmark available methods under various scenarios of baseline expression levels, sample sizes, cell type compositions, expression level alterations, technical noises and biological dispersions. Real data analyses of three large datasets on inflammatory bowel disease, lung cancer and autism provide evaluation in both the gene level and the pathway level. We find that csDEG calling is strongly affected by effect size, baseline expression level and cell type compositions. Results imply that csDEG discovery is a challenging task itself, with room to improvements on handling low signal-to-noise ratio and low expression genes.


Assuntos
Perfilação da Expressão Gênica , Software , Perfilação da Expressão Gênica/métodos , RNA-Seq , Simulação por Computador , Razão Sinal-Ruído , Análise de Sequência de RNA/métodos
5.
Genomics ; 116(3): 110834, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38527595

RESUMO

The edgeR (Robust) is a popular approach for identifying differentially expressed genes (DEGs) from RNA-Seq profiles. However, it shows weak performance against gene-specific outliers and is unable to handle missing observations. To address these issues, we proposed a pre-processing approach of RNA-Seq count data by combining the iLOO-based outlier detection and random forest-based missing imputation approach for boosting the performance of edgeR (Robust). Both simulation and real RNA-Seq count data analysis results showed that the proposed edgeR (Robust) outperformed than the conventional edgeR (Robust). To investigate the effectiveness of identified DEGs for diagnosis, and therapies of ovarian cancer (OC), we selected top-ranked 12 DEGs (IL6, XCL1, CXCL8, C1QC, C1QB, SNAI2, TYROBP, COL1A2, SNAP25, NTS, CXCL2, and AGT) and suggested hub-DEGs guided top-ranked 10 candidate drug-molecules for the treatment against OC. Hence, our proposed procedure might be an effective computational tool for exploring potential DEGs from RNA-Seq profiles for diagnosis and therapies of any disease.


Assuntos
Biomarcadores Tumorais , Neoplasias Ovarianas , RNA-Seq , Humanos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/terapia , Feminino , Biomarcadores Tumorais/genética , Software , Transcriptoma , Perfilação da Expressão Gênica
6.
Genes Chromosomes Cancer ; 63(8): e23256, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39193983

RESUMO

Papillary thyroid carcinoma (PTC), the most common malignancy of follicular cell derivation, is generally associated with good prognosis. Nevertheless, it is important to identify patients with aggressive PTCs and unfavorable outcome. Molecular markers such as BRAFV600E mutation and TERT promoter mutations have been proposed for risk stratification. While TERT promoter mutations have been frequently associated with aggressive PTCs, the association of BRAFV600E mutation with increased recurrence and mortality is less clear and has been controversially discussed. The aim of the present study was to analyze whether differentially expressed genes can predict BRAFV600E mutations as well as TERT promoter mutations in PTCs. RNA sequencing identified a large number of differentially expressed genes between BRAFV600E and BRAFwildtype PTCs. Of those, AHNAK2, DCSTAMP, and FN1 could be confirmed in a larger cohort (n = 91) to be significantly upregulated in BRAFV600E mutant PTCs using quantitative RT-PCR. Moreover, individual PTC expression values of DCSTAMP and FN1 were able to predict the BRAFV600E mutation status with high sensitivity and specificity. The expression of TERT was detected in all PTCs harboring TERT promoter mutations and in 19% of PTCs without TERT promoter mutations. Tumors with both TERT expression and TERT promoter mutations were particularly associated with aggressive clinicopathological features and a shorter recurrence-free survival. Altogether, it will be interesting to explore the biological function of AHNAK2, DCSTAMP, and FN1 in PTC in more detail. The analysis of their expression patterns could allow the characterization of PTC subtypes and thus enabling a more individualized surgical and medical treatment.


Assuntos
Mutação , Recidiva Local de Neoplasia , Telomerase , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Telomerase/genética , Feminino , Masculino , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/patologia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Pessoa de Meia-Idade , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Adulto , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas de Membrana/genética , Idoso , Transcriptoma , Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Regiões Promotoras Genéticas , Proteínas do Citoesqueleto , Fibronectinas
7.
J Infect Dis ; 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39194054

RESUMO

Chagas disease is a neglected tropical infection that affects millions of people. This study explores transcriptomic changes in T. cruzi-infected subjects before and after treatment. Using total RNA sequencing, gene transcription was analyzed in peripheral blood mononuclear cells from asymptomatic (n=19) and symptomatic (n=8) T. cruzi-infected individuals, and non-infected controls (n=15). Differential expression was compared across groups, and before/after treatment in infected subgroups. Untreated infection showed 12 upregulated and 206 downregulated genes in all T. cruzi-infected subjects, and 47 upregulated and 215 downregulated genes in the symptomatic group. Few differentially expressed genes were found after treatment and between the different infected groups. Gene set enrichment analysis highlighted immune-related pathways activated during infection, with therapy normalizing immune function. Changes in the kynurenine/tryptophan ratio, increased pre-treatment, suggested chronic immune fatigue, which was restored post-treatment. These differentially expressed genes offer insights for potential biomarkers and pathways associated with disease progression and treatment response.

8.
BMC Bioinformatics ; 25(1): 259, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39112940

RESUMO

BACKGROUND: Effective identification of differentially expressed genes (DEGs) has been challenging for single-cell RNA sequencing (scRNA-seq) profiles. Many existing algorithms have high false positive rates (FPRs) and often fail to identify weak biological signals. RESULTS: We present a novel method for identifying DEGs in scRNA-seq data called RankCompV3. It is based on the comparison of relative expression orderings (REOs) of gene pairs which are determined by comparing the expression levels of a pair of genes in a set of single-cell profiles. The numbers of genes with consistently higher or lower expression levels than the gene of interest are counted in two groups in comparison, respectively, and the result is tabulated in a 3 × 3 contingency table which is tested by McCullagh's method to determine if the gene is dysregulated. In both simulated and real scRNA-seq data, RankCompV3 tightly controlled the FPR and demonstrated high accuracy, outperforming 11 other common single-cell DEG detection algorithms. Analysis with either regular single-cell or synthetic pseudo-bulk profiles produced highly concordant DEGs with the ground-truth. In addition, RankCompV3 demonstrates higher sensitivity to weak biological signals than other methods. The algorithm was implemented using Julia and can be called in R. The source code is available at https://github.com/pathint/RankCompV3.jl . CONCLUSIONS: The REOs-based algorithm is a valuable tool for analyzing single-cell RNA profiles and identifying DEGs with high accuracy and sensitivity.


Assuntos
Algoritmos , Perfilação da Expressão Gênica , Análise de Sequência de RNA , Análise de Célula Única , Análise de Célula Única/métodos , Perfilação da Expressão Gênica/métodos , Análise de Sequência de RNA/métodos , Transcriptoma/genética , Humanos , Software
9.
J Cell Mol Med ; 28(16): e70010, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39183444

RESUMO

Colorectal cancer (COCA) has a poor prognosis, with growing evidence implicating basement membranes (BMs) in cancer progression. Our goal was to investigate the role and predictive significance of BMs in COCA patients. We obtained BMs-related genes from cutting-edge research and used TCGA and GTEx databases for mRNA expression and patient information. Cox regression and LASSO regression were used for prognostic gene selection and risk model construction. We compared prognosis using Kaplan-Meier analysis and examined drug sensitivity differences. The CMAP dataset identified potential small molecule drugs. In vitro tests involved suppressing a crucial gene to observe its impact on tumour metastasis. We developed a 12 BMs-based approach, finding it to be an independent prognostic factor. Functional analysis showed BMs concentrated in cancer-associated pathways, correlating with immune cell infiltration and immune checkpoint activation. High-risk individuals exhibited increased drug sensitivity. AGRN levels were linked to decreased progression-free survival (p < 0.001). AGRN knockdown suppressed tumour growth and metastasis. Our study offers new perspectives on BMs in COCA, concluding that AGRN is a dependable biomarker for patient survival and prognosis.


Assuntos
Membrana Basal , Biomarcadores Tumorais , Neoplasias Colorretais , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Membrana Basal/metabolismo , Membrana Basal/patologia , Biomarcadores Tumorais/genética , Prognóstico , Feminino , Estimativa de Kaplan-Meier , Masculino , Linhagem Celular Tumoral , Animais , Camundongos
10.
J Cell Mol Med ; 28(2): e18067, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38071502

RESUMO

We intend to evaluate the importance of N7 -methylguanosine (m7G) for the prognosis of breast cancer (BC). We gained 29 m7G-related genes from the published literature and among them, 16 m7G-related genes were found to have differential expression. Five differentially expressed genes (CYFIP1, EIF4E, EIF4E3, NCBP1 and WDR4) were linked to overall survival. This suggests that m7G-related genes might be prognostic or therapeutic targets for BC patients. We put the five genes to LASSO regression analysis to create a four-gene signature, including EIF4E, EIF4E3, WDR4 and NCBP1, that divides samples into two risky groups. Survival was drastically worsened in a high-risk group (p < 0.001). The signature's predictive capacity was demonstrated using ROC (10-year AUC 0.689; 10-year AUC 0.615; 3-year AUC 0.602). We found that immune status was significantly different between the two risk groups. In particular, NCBP1 also has a poor prognosis, with higher diagnostic value in ROC. NCBP1 also has different immune states according to its high or low expression. Meanwhile, knockdown of NCBP1 suppresses BC malignancy in vitro. Therefore, m7G RNA regulators are crucial participants in BC and four-gene mRNA levels are important predictors of prognosis. NCBP1 plays a critical target of m7G mechanism in BC.


Assuntos
Neoplasias da Mama , Guanosina , Feminino , Humanos , Biomarcadores , Neoplasias da Mama/genética , Fator de Iniciação 4E em Eucariotos , Proteínas de Ligação ao GTP , Guanosina/análogos & derivados , Complexo Proteico Nuclear de Ligação ao Cap/metabolismo , Prognóstico
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