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1.
Artigo em Inglês | MEDLINE | ID: mdl-38504574

RESUMO

BACKGROUND AND PURPOSE: Emodin, a compound derived from rhubarb and various traditional Chinese medicines, exhibits a range of pharmacological actions, including antiinflammatory, antiviral, and anticancer properties. Nevertheless, its pharmacological impact on bladder cancer (BLCA) and the underlying mechanism are still unclear. This research aimed to analyze the pharmacological mechanisms of Emodin against BLCA using network pharmacology analysis and experimental verification. METHODS: Initially, network pharmacology was employed to identify core targets and associated pathways affected by Emodin in bladder cancer. Subsequently, the expression of key targets in normal bladder tissues and BLCA tissues was assessed by searching the GEPIA and HPA databases. The binding energy between Emodin and key targets was predicted using molecular docking. Furthermore, in vitro experiments were carried out to confirm the predictions made with network pharmacology. RESULTS: Our analysis identified 148 common genes targeted by Emodin and BLCA, with the top ten target genes including TP53, HSP90AA1, EGFR, MYC, CASP3, CDK1, PTPN11, EGF, ESR1, and TNF. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses indicated a significant correlation between Emodin and the PI3KAKT pathway in the context of BLCA. Molecular docking investigations revealed a strong affinity between Emodin and critical target proteins. In vitro experiments demonstrated that Emodin inhibits T24 proliferation, migration, and invasion while inducing cell apoptosis. The findings also indicated that Emodin reduces both PI3K and AKT protein and mRNA expression, suggesting that Emodin may mitigate BLCA by modulating the PI3K-AKT signaling pathway. CONCLUSION: This study integrates network pharmacology with in vitro experimentation to elucidate the potential mechanisms underlying the action of Emodin against BLCA. The results of this research enhance our understanding of the pharmacological mechanisms by which Emodin may be employed in treating BLCA.

2.
Res Vet Sci ; 141: 164-173, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34749101

RESUMO

Mycoplasma gallisepticum (MG) is a major poultry pathogen that can induce Chronic Respiratory Disease (CRD) in chickens, causing serious economic losses in the poultry industry worldwide. Increasing evidence suggests that microRNAs (miRNAs) act as a vital role in resisting microbial pathogenesis and maintaining cellular mechanism. Our previous miRNAs sequencing data showed gga-miR-24-3p expression level was significantly increased in MG-infected chicken lungs. The aim of this study is to reveal the cellular mechanism behind the MG-HS infection. We found that gga-miR-24-3p was significantly upregulated and Ras-related protein-B (RAP1B) was downregulated in chicken fibroblast cells (DF-1) with MG infection. Dual luciferase reporting assay and rescue assay confirmed that RAP1B was the target gene of gga-miR-24-3p. Meanwhile, overexpressed gga-miR-24-3p increased the levels of tumor necrosis factor alpha (TNF-α) and interleukin-1ß (IL-1ß), and significantly inhibited cell proliferation as well as promoted MG-infected DF-1 cell apoptosis, whereas inhibition of gga-miR-24-3p had the opposite effect. More importantly, the results of overexpression and knockdown of target gene RAP1B demonstrated that the presence of RAP1B promoted cell proliferation and it saved the reduced or increased cell proliferation caused by overexpression or inhibition of gga-miR-24-3p. Furthermore, the overexpression of gga-miR-24-3p could significantly inhibit the expression of MG-HS adhesion protein. Taken together, these findings demonstrate that DF-1 cells can resist MG-HS infection through gga-miR-24-3p/RAP1B mediated decreased proliferation and increased apoptosis, which provides a new mechanism of resistance to MG infection in vitro.


Assuntos
Galinhas , MicroRNAs , Infecções por Mycoplasma/veterinária , Proteínas rap de Ligação ao GTP/genética , Animais , Apoptose , Linhagem Celular , Proliferação de Células , MicroRNAs/genética , Infecções por Mycoplasma/prevenção & controle , Mycoplasma gallisepticum
3.
J Biomol Struct Dyn ; 34(1): 223-35, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25645238

RESUMO

A microRNA (miRNA) is a small non-coding RNA molecule, functioning in transcriptional and post-transcriptional regulation of gene expression. The human genome may encode over 1000 miRNAs. Albeit poorly characterized, miRNAs are widely deemed as important regulators of biological processes. Aberrant expression of miRNAs has been observed in many cancers and other disease states, indicating that they are deeply implicated with these diseases, particularly in carcinogenesis. Therefore, it is important for both basic research and miRNA-based therapy to discriminate the real pre-miRNAs from the false ones (such as hairpin sequences with similar stem-loops). Particularly, with the avalanche of RNA sequences generated in the post-genomic age, it is highly desired to develop computational sequence-based methods for effectively identifying the human pre-miRNAs. Here, we propose a predictor called "iMiRNA-PseDPC", in which the RNA sequences are formulated by a novel feature vector called "pseudo distance-pair composition" (PseDPC) with 10 types of structure statuses. Rigorous cross-validations on a much larger and more stringent newly constructed benchmark data-set showed that our approach has remarkably outperformed the existing ones in either prediction accuracy or efficiency, indicating the new predictor is quite promising or at least may become a complementary tool to the existing predictors in this area. For the convenience of most experimental scientists, a user-friendly web server for the new predictor has been established at http://bioinformatics.hitsz.edu.cn/iMiRNA-PseDPC/, by which users can easily get their desired results without the need to go through the mathematical details. It is anticipated that the new predictor may become a useful high throughput tool for genome analysis particularly in dealing with large-scale data.


Assuntos
MicroRNAs/química , Conformação de Ácido Nucleico , Análise de Sequência de RNA/métodos , Software , Algoritmos , Biologia Computacional , Genoma Humano , Genômica , Humanos , Internet , MicroRNAs/genética
4.
Mol Genet Genomics ; 291(1): 473-81, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26085220

RESUMO

With the rapid growth of RNA sequences generated in the postgenomic age, it is highly desired to develop a flexible method that can generate various kinds of vectors to represent these sequences by focusing on their different features. This is because nearly all the existing machine-learning methods, such as SVM (support vector machine) and KNN (k-nearest neighbor), can only handle vectors but not sequences. To meet the increasing demands and speed up the genome analyses, we have developed a new web server, called "representations of RNA sequences" (repRNA). Compared with the existing methods, repRNA is much more comprehensive, flexible and powerful, as reflected by the following facts: (1) it can generate 11 different modes of feature vectors for users to choose according to their investigation purposes; (2) it allows users to select the features from 22 built-in physicochemical properties and even those defined by users' own; (3) the resultant feature vectors and the secondary structures of the corresponding RNA sequences can be visualized. The repRNA web server is freely accessible to the public at http://bioinformatics.hitsz.edu.cn/repRNA/ .


Assuntos
RNA/genética , Análise de Sequência de RNA/métodos , Sequência de Bases , Biologia Computacional/métodos , Genoma/genética , Internet , Software , Máquina de Vetores de Suporte
5.
Nucleic Acids Res ; 43(W1): W65-71, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25958395

RESUMO

With the avalanche of biological sequences generated in the post-genomic age, one of the most challenging problems in computational biology is how to effectively formulate the sequence of a biological sample (such as DNA, RNA or protein) with a discrete model or a vector that can effectively reflect its sequence pattern information or capture its key features concerned. Although several web servers and stand-alone tools were developed to address this problem, all these tools, however, can only handle one type of samples. Furthermore, the number of their built-in properties is limited, and hence it is often difficult for users to formulate the biological sequences according to their desired features or properties. In this article, with a much larger number of built-in properties, we are to propose a much more flexible web server called Pse-in-One (http://bioinformatics.hitsz.edu.cn/Pse-in-One/), which can, through its 28 different modes, generate nearly all the possible feature vectors for DNA, RNA and protein sequences. Particularly, it can also generate those feature vectors with the properties defined by users themselves. These feature vectors can be easily combined with machine-learning algorithms to develop computational predictors and analysis methods for various tasks in bioinformatics and system biology. It is anticipated that the Pse-in-One web server will become a very useful tool in computational proteomics, genomics, as well as biological sequence analysis. Moreover, to maximize users' convenience, its stand-alone version can also be downloaded from http://bioinformatics.hitsz.edu.cn/Pse-in-One/download/, and directly run on Windows, Linux, Unix and Mac OS.


Assuntos
Análise de Sequência de DNA/métodos , Análise de Sequência de Proteína/métodos , Análise de Sequência de RNA/métodos , Software , Internet , Aprendizado de Máquina
6.
PLoS One ; 10(3): e0121501, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25821974

RESUMO

Containing about 22 nucleotides, a micro RNA (abbreviated miRNA) is a small non-coding RNA molecule, functioning in transcriptional and post-transcriptional regulation of gene expression. The human genome may encode over 1000 miRNAs. Albeit poorly characterized, miRNAs are widely deemed as important regulators of biological processes. Aberrant expression of miRNAs has been observed in many cancers and other disease states, indicating they are deeply implicated with these diseases, particularly in carcinogenesis. Therefore, it is important for both basic research and miRNA-based therapy to discriminate the real pre-miRNAs from the false ones (such as hairpin sequences with similar stem-loops). Particularly, with the avalanche of RNA sequences generated in the postgenomic age, it is highly desired to develop computational sequence-based methods in this regard. Here two new predictors, called "iMcRNA-PseSSC" and "iMcRNA-ExPseSSC", were proposed for identifying the human pre-microRNAs by incorporating the global or long-range structure-order information using a way quite similar to the pseudo amino acid composition approach. Rigorous cross-validations on a much larger and more stringent newly constructed benchmark dataset showed that the two new predictors (accessible at http://bioinformatics.hitsz.edu.cn/iMcRNA/) outperformed or were highly comparable with the best existing predictors in this area.


Assuntos
MicroRNAs/genética , Precursores de RNA/genética , Aminoácidos/genética , Sequência de Bases , Biologia Computacional/métodos , Genoma Humano/genética , Humanos , Conformação de Ácido Nucleico , Nucleotídeos/genética , Pequeno RNA não Traduzido/genética
7.
Mol Biosyst ; 11(4): 1194-204, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25715848

RESUMO

MicroRNA precursor identification is an important task in bioinformatics. Support Vector Machine (SVM) is one of the most effective machine learning methods used in this field. The performance of SVM-based methods depends on the vector representations of RNAs. However, the discriminative power of the existing feature vectors is limited, and many methods lack an interpretable model for analysis of characteristic sequence features. Prior studies have demonstrated that sequence or structure order effects were relevant for discrimination, but little work has explored how to use this kind of information for human pre-microRNA identification. In this study, in order to incorporate the structure-order information into the prediction, a method called "miRNA-dis" was proposed, in which the feature vector was constructed by the occurrence frequency of the "distance structure status pair" or just the "distance-pair". Rigorous cross-validations on a much larger and more stringent newly constructed benchmark dataset showed that the miRNA-dis outperformed some state-of-the-art predictors in this area. Remarkably, miRNA-dis trained with human data can correctly predict 87.02% of the 4022 pre-miRNAs from 11 different species ranging from animals, plants and viruses. miRNA-dis would be a useful high throughput tool for large-scale analysis of microRNA precursors. In addition, the learnt model can be easily analyzed in terms of discriminative features, and some interesting patterns were discovered, which could reflect the characteristics of microRNAs. A user-friendly web-server of miRNA-dis was constructed, which is freely accessible to the public at the web-site on http://bioinformatics.hitsz.edu.cn/miRNA-dis/.


Assuntos
Biologia Computacional/métodos , MicroRNAs/química , MicroRNAs/genética , Interface Usuário-Computador , Animais , Bases de Dados Genéticas , Humanos , Internet , RNA de Plantas , RNA Viral
8.
Bioinformatics ; 31(8): 1307-9, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25504848

RESUMO

UNLABELLED: In order to develop powerful computational predictors for identifying the biological features or attributes of DNAs, one of the most challenging problems is to find a suitable approach to effectively represent the DNA sequences. To facilitate the studies of DNAs and nucleotides, we developed a Python package called representations of DNAs (repDNA) for generating the widely used features reflecting the physicochemical properties and sequence-order effects of DNAs and nucleotides. There are three feature groups composed of 15 features. The first group calculates three nucleic acid composition features describing the local sequence information by means of kmers; the second group calculates six autocorrelation features describing the level of correlation between two oligonucleotides along a DNA sequence in terms of their specific physicochemical properties; the third group calculates six pseudo nucleotide composition features, which can be used to represent a DNA sequence with a discrete model or vector yet still keep considerable sequence-order information via the physicochemical properties of its constituent oligonucleotides. In addition, these features can be easily calculated based on both the built-in and user-defined properties via using repDNA. AVAILABILITY AND IMPLEMENTATION: The repDNA Python package is freely accessible to the public at http://bioinformatics.hitsz.edu.cn/repDNA/. CONTACT: bliu@insun.hit.edu.cn or kcchou@gordonlifescience.org SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Biologia Computacional/métodos , DNA/química , DNA/genética , Oligonucleotídeos/química , Análise de Sequência de DNA/métodos , Software , Máquina de Vetores de Suporte , Humanos , Oligonucleotídeos/genética
9.
ScientificWorldJournal ; 2014: 464093, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25133234

RESUMO

Identification of protein binding sites is critical for studying the function of the proteins. In this paper, we proposed a method for protein binding site prediction, which combined the order profile propensities and hidden Markov support vector machine (HM-SVM). This method employed the sequential labeling technique to the field of protein binding site prediction. The input features of HM-SVM include the profile-based propensities, the Position-Specific Score Matrix (PSSM), and Accessible Surface Area (ASA). When tested on different data sets, the proposed method showed promising results, and outperformed some closely relative methods by more than 10% in terms of AUC.


Assuntos
Proteínas/química , Análise de Sequência de Proteína/métodos , Máquina de Vetores de Suporte , Sítios de Ligação , Modelos Químicos , Proteínas/metabolismo
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