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1.
Cancers (Basel) ; 15(10)2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37345178

RESUMO

AIM: EBV encodes at least 44 miRNAs involved in immune regulation and disease progression. Exosomes can be used as carriers of EBV-miRNA-BART intercellular transmission and affect the biological behavior of cells. We characterized exosomes and established a co-culture experiment of exosomes to explore the mechanism of miR-BART1-3p transmission through the exosome pathway and its influence on tumor cell proliferation and invasion. MATERIALS AND METHODS: Exosomes of EBV-positive and EBV-negative gastric cancer cells were characterized by transmission electron microscopy. NanoSight and Western blotting, and miRNA expression profiles in exosomes were sequenced with high throughput. Exosomes with high or low expression of miR-BART1-3p were co-cultured with AGS cells to study the effects on proliferation, invasion, and migration of gastric cancer cells. The target genes of EBV-miR-BART1-3p were screened and predicted by PITA, miRanda, RNAhybrid, virBase, and DIANA-TarBase v.8 databases, and the expression of the target genes after co-culture was detected by qPCR. RESULTS: The exosomes secreted by EBV-positive and negative gastric cancer cells range in diameter from 30 nm to 150 nm and express the exosomal signature proteins CD9 and CD63. Small RNA sequencing showed that exosomes expressed some human miRNAs, among which hsa-miR-23b-3p, hsa-miR-320a-3p, and hsa-miR-4521 were highly expressed in AGS-exo; hsa-miR-21-5p, hsa-miR-148a-3p, and hsa-miR-7-5p were highly expressed in SNU-719-exo. All EBV miRNAs were expressed in SNU-719 cells and their exosomes, among which EBV-miR-BART1-5p, EBV-miR-BART22, and EBV-miR-BART16 were the highest in SNU-719 cells; EBV-miR-BART1-5p, EBV-miR-BART10-3p, and EBV-miR-BART16 were the highest in SNU-719-exo. After miR-BART1-3p silencing in gastric cancer cells, the proliferation, healing, migration, and invasion of tumor cells were significantly improved. Laser confocal microscopy showed that exosomes could carry miRNA into recipient cells. After co-culture with miR-BART1-3p silenced exosomes, the proliferation, healing, migration, and invasion of gastric cancer cells were significantly improved. The target gene of miR-BART1-3p was FAM168A, MACC1, CPEB3, ANKRD28, and USP37 after screening by a targeted database. CPEB3 was not expressed in all exosome co-cultured cells, while ANKRD28, USP37, MACC1, and FAM168A were all expressed to varying degrees. USP37 and MACC1 were down-regulated after up-regulation of miR-BART1-3p, which may be the key target genes for miR-BART1-3p to regulate the proliferation of gastric cancer cells through exosomes. CONCLUSIONS: miR-BART1-3p can affect the growth of tumor cells through the exosome pathway. The proliferation, healing, migration, and invasion of gastric cancer cells were significantly improved after co-culture with exosomes of miR-BART1-3p silenced expression. USP37 and MACC1 may be potential target genes of miR-BART1-3p in regulating cell proliferation.

2.
Phys Rev E ; 105(6-1): 064139, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35854588

RESUMO

The latest advances of statistical physics have shown remarkable performance of machine learning in identifying phase transitions. In this paper, we apply domain adversarial neural network (DANN) based on transfer learning to studying nonequilibrium and equilibrium phase transition models, which are percolation model and directed percolation (DP) model, respectively. With the DANN, only a small fraction of input configurations (two-dimensional images) needs to be labeled, which is automatically chosen, to capture the critical point. To learn the DP model, the method is refined by an iterative procedure in determining the critical point, which is a prerequisite for the data collapse in calculating the critical exponent ν_{⊥}. We then apply the DANN to a two-dimensional site percolation with configurations filtered to include only the largest cluster which may contain the information related to the order parameter. The DANN learning of both models yields reliable results which are comparable to the ones from Monte Carlo simulations. Our study also shows that the DANN can achieve quite high accuracy at much lower cost, compared to the supervised learning.

3.
Front Immunol ; 13: 1055412, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36713370

RESUMO

Background: Medullary thyroid carcinoma (MTC), a thyroid C cell-derived malignancy, is poorly differentiated and more aggressive than papillary, follicular and oncocytic types of thyroid cancer. The current therapeutic options are limited, with a third of population suffering resistance. The differential gene expression pattern among thyroid cancer subtypes remains unclear. This study intended to explore the exclusive gene profile of MTC and construct a comprehensive regulatory network via integrated analysis, to uncover the potential key biomarkers. Methods: Multiple datasets of thyroid and other neuroendocrine tumors were obtained from GEO and TCGA databases. Differentially expressed genes (DEGs) specific in MTC were identified to construct a transcription factor (TF)-mRNA-miRNA network. The impact of the TF-mRNA-miRNA network on tumor immune characteristics and patient survival was further explored by single-sample GSEA (ssGSEA) and ESTIMATE algorithms, as well as univariate combined with multivariate analyses. RT-qPCR, cell viability and apoptosis assays were performed for in vitro validation. Results: We identified 81 genes upregulated and 22 downregulated in MTC but not in other types of thyroid tumor compared to the normal thyroid tissue. According to the L1000CDS2 database, potential targeting drugs were found to reverse the expressions of DEGs, with panobinostat (S1030) validated effective for tumor repression in MTC by in vitro experiments. The 103 DEGs exclusively seen in MTC were involved in signal release, muscle contraction, pathways of neurodegeneration diseases, neurotransmitter activity and related amino acid metabolism, and cAMP pathway. Based on the identified 15 hub genes, a TF-mRNA-miRNA linear network, as well as REST-cored coherent feed-forward loop networks, namely REST-KIF5C-miR-223 and REST-CDK5R2-miR-130a were constructed via online prediction and validation by public datasets and our cohort. Hub-gene, TF and miRNA scores in the TF-mRNA-miRNA network were related to immune score, immune cell infiltration and immunotherapeutic molecules in MTC as well as in neuroendocrine tumor of lung and neuroblastoma. Additionally, a high hub-gene score or a low miRNA score indicated good prognoses of neuroendocrine tumors. Conclusion: The present study uncovers underlying molecular mechanisms and potential immunotherapy-related targets for the pathogenesis and drug discovery of MTC.


Assuntos
Carcinoma Neuroendócrino , MicroRNAs , Neoplasias da Glândula Tireoide , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Fatores de Transcrição/genética , RNA Mensageiro/genética , Perfilação da Expressão Gênica , Carcinoma Neuroendócrino/tratamento farmacológico , Carcinoma Neuroendócrino/genética , Neoplasias da Glândula Tireoide/patologia
4.
J Colloid Interface Sci ; 325(2): 331-6, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18555263

RESUMO

Structure transition from aragonite to vaterite and calcite with the help of anionic surfactant sodium dodecyl benzene sulfonate (SDBS) was investigated, respectively, by a hydrothermal method. When the experimental temperature was controlled at 90 degrees C, aragonite of crystal calcium carbonate was transformed into vaterite with the assistance of SDBS. Pure vaterite was obtained as the concentration of SDBS reaches to 2.5 mM. When the experimental temperature was controlled at 120 and 150 degrees C, respectively, aragonite was transformed into calcite, and pure calcite was obtained as the concentrations of SDBS were equal to 1.0 and 2.5 mM, respectively. Possible formation mechanism of different CaCO(3) polymorphs was proposed based on the obtained experimental results.

5.
Inorg Chem ; 38(9): 1966-1970, 1999 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-11670973

RESUMO

Co(SCH(2)CH(2)NH(2))(3) has been capped on the facial amines through protection of the thiolates by coordination of two such complexes to a central Co(III) ion. The trinuclear species forming the framework is the complex ion [Co{Co(SCH(2)CH(2)NH(2))(3)}(2)](3+), 1, in meso and rac forms which have been chromatographically separated and identified. Hexaimine derivatives of 1, [Co{Co(SCH(2)CH(2)N=CH(2))(3)}(2)](3+), 2, have been synthesized in good yield by reaction with excess paraformaldehyde and base in CH(3)CN. The hexaimines have been reacted with NH(3) to yield dicapped aza species [Co{Co(SCH(2)CH(2)NHCH(2))(3)N}(2)](3+), 3, or reacted with nitromethane to yield the nitro-capped ions [Co{Co(SCH(2)CH(2)NHCH(2)C)(3)CNO(2)}(2)](3+), 4. The reactions are retentive; i.e., meso reactant yields meso product. All of the products have been characterized by (1)H NMR, (13)C NMR, and UV-vis spectroscopy. Electrochemical measurements (CV and dc coulometry) in CH(3)CN indicate that the central Co(III) ion in all of the species is reduced first, followed by the two terminal Co(III) centers. The formal potentials show that the Co(III) oxidation state is stabilized by the six thiolate bridging ligands in comparison to six thioether donor atoms, whereas capping has a destabilizing effect.

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