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1.
Mol Biol Rep ; 51(1): 339, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38393419

RESUMO

BACKGROUND: Age-related macular degeneration (AMD) is a prevalent source of visual impairment among the elderly population, and its incidence has risen in tandem with the increasing longevity of humans. Despite the progress made with anti-VEGF therapy, clinical outcomes have proven to be unsatisfactory. METHOD: We obtained differentially expressed genes (DEGs) of AMD patients and healthy controls from the GEO database. GO and KEGG analyses were used to enrich the DEGs. Weighted gene coexpression network analysis (WGCNA) was used to identify modules related to AMD. SVM, random forest, and least absolute shrinkage and selection operator (LASSO) were employed to screen hub genes. Gene set enrichment analysis (GSEA) was used to explore the pathways in which these hub genes were enriched. CIBERSORT was utilized to analyze the relationship between the hub genes and immune cell infiltration. Finally, Western blotting and RT‒PCR were used to explore the expression of hub genes in AMD mice. RESULTS: We screened 1084 DEGs in GSE29801, of which 496 genes were upregulated. These 1084 DEGs were introduced into the WGCNA, and 94 genes related to AMD were obtained. Seventy-nine overlapping genes were obtained by the Venn plot. These 79 genes were introduced into three machine-learning methods to screen the hub genes, and the genes identified by the three methods were TNC, FAP, SREBF1, and TGF-ß2. We verified their diagnostic function in the GSE29801 and GSE103060 datasets. Then, the hub gene co-enrichment pathways were obtained by GO and KEGG analyses. CIBERSORT analysis showed that these hub genes were associated with immune cell infiltration. Finally, we found increased expression of TNC, FAP, SREBF1, and TGF-ß2 mRNA and protein in the retinas of AMD mice. CONCLUSION: We found that four hub genes, namely, FAP, TGF-ß2, SREBF1, and TNC, have diagnostic significance in patients with AMD and are related to immune cell infiltration. Finally, we determined that the mRNA and protein expression of these hub genes was upregulated in the retinas of AMD mice.


Assuntos
Degeneração Macular , Fator de Crescimento Transformador beta2 , Humanos , Idoso , Animais , Camundongos , Fator de Crescimento Transformador beta2/genética , Degeneração Macular/genética , Retina , Western Blotting , RNA Mensageiro
2.
BMC Urol ; 24(1): 136, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956663

RESUMO

BACKGROUND: In recent years, Genome-Wide Association Studies (GWAS) has identified risk variants related to complex diseases, but most genetic variants have less impact on phenotypes. To solve the above problems, methods that can use variants with low genetic effects, such as genetic risk score (GRS), have been developed to predict disease risk. METHODS: As the GRS model with the most incredible prediction power for complex diseases has not been determined, our study used simulation data and prostate cancer data to explore the disease prediction power of three GRS models, including the simple count genetic risk score (SC-GRS), the direct logistic regression genetic risk score (DL-GRS), and the explained variance weighted GRS based on directed logistic regression (EVDL-GRS). RESULTS AND CONCLUSIONS: We used 26 SNPs to establish GRS models to predict the risk of biochemical recurrence (BCR) after radical prostatectomy. Combining clinical variables such as age at diagnosis, body mass index, prostate-specific antigen, Gleason score, pathologic T stage, and surgical margin and GRS models has better predictive power for BCR. The results of simulation data (statistical power = 0.707) and prostate cancer data (area under curve = 0.8462) show that DL-GRS has the best prediction performance. The rs455192 was the most relevant locus for BCR (p = 2.496 × 10-6) in our study.


Assuntos
Recidiva Local de Neoplasia , Prostatectomia , Neoplasias da Próstata , Neoplasias da Próstata/genética , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/sangue , Masculino , Humanos , Recidiva Local de Neoplasia/genética , Medição de Risco/métodos , Pessoa de Meia-Idade , Idoso , Polimorfismo de Nucleotídeo Único , Estudo de Associação Genômica Ampla , Valor Preditivo dos Testes , Estratificação de Risco Genético
3.
Int J Mol Sci ; 24(3)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36768307

RESUMO

Super-enhancers (SEs) regulate gene expressions, which are critical for cell type-identity and tumorigenesis. Although genome wide H3K27ac profiling have revealed the presence of SE-associated genes in gastric cancer (GC), their roles remain unclear. In this study, ChIP-seq and HiChIP-seq experiments revealed mitogen-activated protein kinase 8 (MAP3K8) to be an SE-associated gene with chromosome interactions in Epstein-Barr virus-associated gastric carcinoma (EBVaGC) cells. CRISPRi mediated repression of the MAP3K8 SEs attenuated MAP3K8 expression and EBVaGC cell proliferation. The results were validated by treating EBVaGC cells with bromodomain and the extra-terminal motif (BET) inhibitor, OTX015. Further, functional analysis of MAP3K8 in EBVaGC revealed that silencing MAP3K8 could inhibit the cell proliferation, colony formation, and migration of EBVaGC cells. RNA-seq and pathway analysis indicated that knocking down MAP3K8 obstructed the notch signaling pathway and epithelial-mesenchymal transition (EMT) in EBVaGC cells. Further, analysis of the cancer genome atlas (TCGA) and GSE51575 databases exhibited augmented MAP3K8 expression in gastric cancer and it was found to be inversely correlated with the disease-free progression of GC. Moreover, Spearman's correlation revealed that MAP3K8 expression was positively correlated with the expressions of notch pathway and EMT related genes, such as, Notch1, Notch2, C-terminal binding protein 2 (CTBP2), alpha smooth muscle actin isotype 2 (ACTA2), transforming growth factor beta receptor 1 (TGFßR1), and snail family transcriptional repressors 1/2 (SNAI1/SNAI2) in GC. Taken together, we are the first to functionally interrogate the mechanism of SE-mediated regulation of MAP3K8 in EBVaGC cell lines.


Assuntos
Epigênese Genética , Infecções por Vírus Epstein-Barr , MAP Quinase Quinase Quinases , Neoplasias Gástricas , Humanos , Epigênese Genética/genética , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/patologia , Regulação Neoplásica da Expressão Gênica/genética , Herpesvirus Humano 4/genética , MAP Quinase Quinase Quinases/genética , Proteínas Proto-Oncogênicas/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Neoplasias Gástricas/virologia
4.
Int J Cancer ; 147(2): 505-518, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32064600

RESUMO

Although early detection and systemic therapies have improved the diagnosis and clinical cure rate of breast cancer, breast cancer remains the most frequently occurring malignant cancer in women due to a lack of sufficiently effective treatments. Thus, to develop potential targeted therapies and thus benefit more patients, it is helpful to understand how cancer cells work. ZIC family members have been shown to play important roles in neural development and carcinogenesis. In our study, we found that ZIC2 is downregulated in breast cancer tissues at both the mRNA and protein levels. Low expression of ZIC2 was correlated with poor outcome in breast cancer patients and serves as an independent prognostic marker. Furthermore, overexpression of ZIC2 repressed, whereas knockdown of ZIC2 promoted, cell proliferation and colony formation ability in vitro and tumor growth in vivo. Using ChIP-seq and RNA-seq analysis, we screened and identified STAT3 as a potential target for ZIC2. ZIC2 bound to the STAT3 promoter and repressed the promoter activities of STAT3. ZIC2 knockdown induced the expression of STAT3, increasing the level of phosphorylated STAT3. These results suggest that ZIC2 regulates the transcription of STAT3 by directly binding to the STAT3 promoter. Additionally, interfering STAT3 with siRNAs or inhibitors abrogated the oncogenic effects induced by decreased ZIC2. Taken together, our results indicate that ZIC2 serves as a useful prognostic marker in breast cancer and acts as a tumor suppressor by regulating STAT3, implying that STAT3 inhibitors might provide an alternative treatment option for breast cancer patients with ZIC2 downregulation.


Assuntos
Neoplasias da Mama/patologia , Regulação para Baixo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Sequenciamento de Cromatina por Imunoprecipitação , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Camundongos , Transplante de Neoplasias , Fosforilação , Prognóstico , Regiões Promotoras Genéticas , Análise de Sequência de RNA , Transdução de Sinais
5.
Bioorg Med Chem Lett ; 28(16): 2794-2796, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29079470

RESUMO

RNA regulation and maintenance are critical for proper cell function. Small molecules that specifically alter RNA sequence would be exceptionally useful as probes of RNA structure and function or as potential therapeutics. Here, we demonstrate a photochemical approach for altering the trinucleotide expanded repeat causative of myotonic muscular dystrophy type 1 (DM1), r(CUG)exp. The small molecule, 2H-4-Ru, binds to r(CUG)exp and converts guanosine residues to 8-oxo-7,8-dihydroguanosine upon photochemical irradiation. We demonstrate targeted modification upon irradiation in cell culture and in Drosophila larvae provided a diet containing 2H-4-Ru. Our results highlight a general chemical biology approach for altering RNA sequence in vivo by using small molecules and photochemistry. Furthermore, these studies show that addition of 8-oxo-G lesions into RNA 3' untranslated regions does not affect its steady state levels.


Assuntos
RNA/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Sequência de Bases , Células Cultivadas , Drosophila , Estrutura Molecular , Processos Fotoquímicos , RNA/química , RNA/metabolismo , Bibliotecas de Moléculas Pequenas/química
6.
Chembiochem ; 15(14): 2041-4, 2014 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-25115866

RESUMO

One challenge in chemical biology is to develop small molecules that control cellular protein content. The amount and identity of proteins are influenced by the RNAs that encode them; thus, protein content in a cell could be affected by targeting mRNA. However, RNA has been traditionally difficult to target with small molecules. In this report, we describe controlling the protein products of the mutated microtubule-associated protein tau (MAPT) mature mRNA with a small molecule. MAPT mutations in exon 10 are associated with inherited frontotemporal dementia and Parkinsonism linked to chromosome 17 (FTDP-17), an incurable disease that is directly caused by increased inclusion of exon 10 in MAPT mRNA. Recent studies have shown that mutations within a hairpin at the MAPT exon 10-intron junction decrease the thermodynamic stability of the RNA, increasing binding to U1 snRNP and thus exon 10 inclusion. Therefore, we designed small molecules that bind and stabilize a mutant MAPT by using Inforna, a computational approach based on information about RNA-small-molecule interactions. The optimal compound selectively bound the mutant MAPT hairpin and thermodynamically stabilized its folding, facilitating exon 10 exclusion.


Assuntos
Desenho de Fármacos , Éxons/efeitos dos fármacos , Precursores de RNA/genética , RNA Mensageiro/genética , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Proteínas tau/genética , Humanos , Mutação/efeitos dos fármacos , Transtornos Parkinsonianos/tratamento farmacológico , Transtornos Parkinsonianos/genética
7.
Nucleic Acids Res ; 40(7): e48, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22210888

RESUMO

The Differential Radial Capillary Action of Ligand Assay (DRaCALA) allows detection of protein interactions with low-molecular weight ligands based on separation of the protein-ligand complex by differential capillary action. Here, we present an application of DRaCALA to the study of nucleic acid-protein interactions using the Escherichia coli cyclic AMP receptor protein (CRP). CRP bound in DRaCALA specifically to (32)P-labeled oligonucleotides containing the consensus CRP binding site, but not to oligonucleotides with point mutations known to abrogate binding. Affinity and kinetic studies using DRaCALA yielded a dissociation constant and dissociation rate similar to previously reported values. Because DRaCALA is not subject to ligand size restrictions, whole plasmids with a single CRP-binding site were used as probes, yielding similar results. DNA can also function as an easily labeled carrier molecule for a conjugated ligand. Sequestration of biotinylated nucleic acids by streptavidin allowed nucleic acids to take the place of the protein as the immobile binding partner. Therefore, any molecular interactions involving nucleic acids can be tested. We demonstrate this principle utilizing a bacterial riboswitch that binds cyclic-di-guanosine monophosphate. DRaCALA is a flexible and complementary approach to other biochemical methods for rapid and accurate measurements of affinity and kinetics at near-equilibrium conditions.


Assuntos
Técnicas de Sonda Molecular , Ácidos Nucleicos/metabolismo , Sítios de Ligação , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , DNA/química , DNA/metabolismo , Sondas de DNA/química , Proteínas de Ligação a DNA/metabolismo , Proteínas de Escherichia coli/metabolismo , Cinética , Ligantes , Sondas de Oligonucleotídeos/química , Plasmídeos/genética , Receptores de AMP Cíclico/metabolismo , Riboswitch
8.
Chem Soc Rev ; 42(1): 305-41, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-23023210

RESUMO

For an organism to survive, it must be able to sense its environment and regulate physiological processes accordingly. Understanding how bacteria integrate signals from various environmental factors and quorum sensing autoinducers to regulate the metabolism of various nucleotide second messengers c-di-GMP, c-di-AMP, cGMP, cAMP and ppGpp, which control several key processes required for adaptation is key for efforts to develop agents to curb bacterial infections. In this review, we provide an update of nucleotide signaling in bacteria and show how these signals intersect or integrate to regulate the bacterial phenotype. The intracellular concentrations of nucleotide second messengers in bacteria are regulated by synthases and phosphodiesterases and a significant number of these metabolism enzymes had been biochemically characterized but it is only in the last few years that the effector proteins and RNA riboswitches, which regulate bacterial physiology upon binding to nucleotides, have been identified and characterized by biochemical and structural methods. C-di-GMP, in particular, has attracted immense interest because it is found in many bacteria and regulate both biofilm formation and virulence factors production. In this review, we discuss how the activities of various c-di-GMP effector proteins and riboswitches are modulated upon c-di-GMP binding. Using V. cholerae, E. coli and B. subtilis as models, we discuss how both environmental factors and quorum sensing autoinducers regulate the metabolism and/or processing of nucleotide second messengers. The chemical syntheses of the various nucleotide second messengers and the use of analogs thereof as antibiofilm or immune modulators are also discussed.


Assuntos
Monofosfato de Adenosina/fisiologia , Infecções Bacterianas/fisiopatologia , Fenômenos Fisiológicos Bacterianos , Guanosina Monofosfato/fisiologia , Percepção de Quorum , Transdução de Sinais , Bactérias/classificação , Bactérias/genética
9.
J Affect Disord ; 361: 91-96, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38857627

RESUMO

BACKGROUND: This study aims to explore the mediating and moderating effect of health-promoting lifestyles on the relationship between frailty and depressive symptoms to provide a practical reference for effectively promoting the mental health of older adults. METHODS: A cross-sectional survey of community-dwelling older adults (n = 3107) was conducted in three cities of Ningxia Province, China. Depressive symptoms, frailty, and health-promoting lifestyles were assessed through the 30-item Geriatric Depression Scale, frailty scale, and health-promoting Lifestyle profile-II, respectively. The Bootstrap methods PROCESS program is employed to test the mediation and moderation model. RESULTS: The findings indicated that health-promoting lifestyles are negatively related to depressive symptoms and frailty, while frailty is positively associated with depressive symptoms. Health-promoting lifestyles have mediated the relationship between frailty and depressive symptoms. Besides, the health-promoting lifestyles weakened the positive relationship between frailty and depression symptoms; there existed a moderating effect of health-promoting lifestyles on the relationship between frailty and depression symptoms among older adults. LIMITATIONS: Given the cross-sectional study, it is impossible to make causal inferences. CONCLUSIONS: A health-promoting lifestyle might be a protective factor for older adults' health in China. The mediating and moderating effect of a health-promoting lifestyle on the relationship between frailty and depression symptoms among older adults should be integrated to achieve maximum utility. Healthcare practitioners and medical service personnel are recommended to advance health education and publicity, encouraging healthy lifestyles among community-dwelling older adults with frailty to prevent depressive symptoms and promote healthy aging.

10.
Sci Rep ; 14(1): 342, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172162

RESUMO

Mitochondrial metabolism has been shown to play a key role in immune cell survival and function, but mitochondrial creatine kinase 2 (CKMT2) has been relatively little studied about tumor immunity. We aimed to explore the prognostic value of CKMT2 in 33 cancer types and investigate its potential immune function. We used a range of bioinformatics approaches to explore the potential carcinogenic role of CKMT2 in multiple cancers. CKMT2 was lowly expressed in 14 tumor tissues and highly expressed in 4 tumor tissues. Immunohistochemical assays showed overexpression of CKMT2 in colon cancer and rectal cancer. CKMT2 overexpression was positively correlated with the prognosis of lung adenocarcinoma and prostate cancer. CKMT2 overexpression is mainly enriched in the adaptive immune system and immune regulatory pathways of immunoglobulins. Seven cancers were positively correlated with low CKMT2 expression in tumor microenvironment analysis. Among the five cancers, low expression of CKMT2 resulted in better immunotherapy treatment outcomes. There was a strong correlation between CKMT2 and most immune-related genes in specific cancer types. CKMT2 plays an important role in tumorigenesis and cancer immunity and can be used as a prognostic biomarker and potential target for cancer immunotherapy.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias do Colo , Neoplasias Pulmonares , Neoplasias da Próstata , Masculino , Humanos , Prognóstico , Carcinogênese , Microambiente Tumoral/genética , Creatina Quinase Mitocondrial
11.
Nucleic Acids Res ; 39(19): 8559-71, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21742763

RESUMO

Obtaining homogeneous population of natively folded RNAs is a crippling problem encountered when preparing RNAs for structural or enzymatic studies. Most of the traditional methods that are employed to prepare large quantities of RNAs involve procedures that partially denature the RNA. Here, we present a simple strategy using 'click' chemistry to couple biotin to a 'caged' photocleavable (PC) guanosine monophosphate (GMP) in high yield. This biotin-PC GMP, accepted by T7 RNA polymerase, has been used to transcribe RNAs ranging in size from 27 to 527 nt. Furthermore we show, using an in-gel fluorescence assay, that natively prepared 160 and 175 kDa minimal group II intron ribozymes have enhanced catalytic activity over the same RNAs, purified via denaturing conditions and refolded. We conclude that large complex RNAs prepared by non-denaturing means form a homogeneous population and are catalytically more active than those prepared by denaturing methods and subsequent refolding; this facile approach for native RNA preparation should benefit synthesis of RNAs for biophysical and therapeutic applications.


Assuntos
Guanosina Monofosfato/química , RNA Catalítico/biossíntese , RNA/biossíntese , Avidina/química , Sequência de Bases , Biotinilação , Catálise , Cromatografia de Afinidade , Química Click , RNA Polimerases Dirigidas por DNA/metabolismo , Íntrons , Dados de Sequência Molecular , Processos Fotoquímicos , RNA/química , RNA/isolamento & purificação , RNA Catalítico/metabolismo , RNA Ribossômico/metabolismo , Transcrição Gênica , Proteínas Virais/metabolismo
12.
Cell Death Dis ; 14(7): 455, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37479694

RESUMO

Nasopharyngeal carcinoma (NPC) is a common malignant epithelial tumor of the head and neck that often exhibits local recurrence and distant metastasis. The molecular mechanisms are understudied, and effective therapeutic targets are still lacking. In our study, we found that the transcription factor ZIC2 was highly expressed in NPC. Although ZIC family members play important roles in neural development and carcinogenesis, the specific mechanism and clinical significance of ZIC2 in the tumorigenesis and immune regulation of NPC remain elusive. Here, we first reported that high expression of ZIC2 triggered the secretion of MCSF in NPC cells, induced M2 polarization of tumor-associated macrophages (TAMs), and affected the secretion of TAM-related cytokines. Mechanistically, ChIP-seq and RNA-seq analyses identified JUNB as a downstream target of ZIC2. Furthermore, ZIC2 was significantly enriched in the promoter site of JUNB and activated JUNB promoter activity, as shown by ChIP-qPCR and luciferase assays. In addition, JUNB and MCSF participated in ZIC2-induced M2 TAMs polarization. Thus, blocking JUNB and MCSF could reverse ZIC2-mediated M2 TAMs polarization. Moreover, Kaplan-Meier survival analyses indicated that high expression of ZIC2, JUNB, and CD163 was positively associated with a poor prognosis in NPC. Overexpression of ZIC2 induced tumor growth in vivo, with the increase of JUNB, MCSF secretion, and CD163. In summary, our study implies that ZIC2 induces M2 TAM polarization, at least in part through regulation of JUNB/MCSF and that ZIC2, JUNB, and CD163 can be utilized as prognostic markers for NPC and as therapeutic targets for cancer immunotherapy.


Assuntos
Carcinoma , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , Carcinogênese , Neoplasias Nasofaríngeas/genética , Macrófagos , Proteínas Nucleares , Fatores de Transcrição/genética
13.
Sci Rep ; 13(1): 22804, 2023 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-38129557

RESUMO

The goal of this study was to develop a ferroptosis-based molecular signature that can predict recurrence-free survival (RFS) in patients with prostate cancer (PCa). In this study, we obtained ferroptosis-related genes (FRGs) in FerrDb database and clinical transcriptome data in TCGA database and GEO database. Consensus cluster analysis was used to identify three molecular markers of ferroptosis in PCa with differential expression of 40 FRGs, including PD-L1 expression levels. We conducted a new ferroptosis-related signature for PCa RFS using four FRGs identified through univariate and multivariate Cox regression analyses. The signature was validated in the training, testing, and validation cohorts, and it demonstrated remarkable results in the area under the time-dependent receiver operating characteristic (ROC) curve of 0.757, 0.715, and 0.732, respectively. Additionally, we observed that younger patients, those with stage T III and stage T IV, stage N0, cluster 1, and cluster 2 PCa were more accurately predicted by the signature as independent predictors of RFS. DU-145 and RWPE-1 cells were successfully analyzed by qRT-PCR and Western blot for ASNS, GPT2, RRM2, and NFE2L2. In summary, we developed a novel ferroptosis-based signature for RFS in PC, utilizing four FRGs identified through univariate and multivariate Cox regression analyses. This signature was rigorously validated across training, testing, and validation cohorts, demonstrating exceptional performance as evidenced by its ROC curves. Notably, our findings indicate that this signature is particularly effective as an independent predictor of RFS in younger patients or those with stage T III and T IV, stage N0, and in clusters 1 and 2. Finally, we confirmed the expression of these four FRGs in DU-145 and RWPE-1 cell lines.


Assuntos
Ferroptose , Neoplasias da Próstata , Masculino , Humanos , Ferroptose/genética , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/genética , Biomarcadores , Western Blotting , Linhagem Celular
14.
EBioMedicine ; 98: 104870, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37967508

RESUMO

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a malignant head and neck cancer with a high incidence in Southern China and Southeast Asia. Patients with remote metastasis and recurrent NPC have poor prognosis. Thus, a better understanding of NPC pathogenesis may identify novel therapies to address the unmet clinical needs. METHODS: H3K27ac ChIP-seq and HiChIP was applied to understand the enhancer landscapes and the chromosome interactions. Whole genome sequencing was conducted to analyze the relationship between genomic variations and epigenetic dysregulation. CRISPRi and JQ1 treatment were used to evaluate the transcriptional regulation of SOX2 SEs. Colony formation assay, survival analysis and in vivo subcutaneous patient-derived xenograft assays were applied to explore the function and clinical relevance of SOX2 in NPC. FINDINGS: We globally mapped the enhancer landscapes and generated NPC enhancer connectomes, linking NPC specific enhancers and SEs. We found five overlapped genes, including SOX2, among super-enhancer regulated genes, survival related genes and NPC essential genes. The mRNA expression of SOX2 was repressed when applying CRISPRi targeting different SOX2 SEs or JQ1 treatment. Next, we identified a genetic variation (Chr3:181422197, G > A) in SOX2 SE which is correlated with higher expression of SOX2 and poor survival. In addition, SOX2 was highly expressed in NPC and is correlated with short survival in patients with NPC. Knock-down of SOX2 suppressed tumor growth in vitro and in vivo. INTERPRETATION: Our study demonstrated the super-enhancer landscape with chromosome interactions and identified super-enhancer driven SOX2 promotes tumorigenesis, suggesting that SOX2 is a potential therapeutic target for patients with NPC. FUNDING: A full list of funding bodies that contributed to this study can be found in the Acknowledgements section.


Assuntos
Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patologia , Recidiva Local de Neoplasia/genética , Análise de Sobrevida , Cromatina/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proliferação de Células , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo
15.
J Biomol NMR ; 52(2): 103-14, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22124680

RESUMO

Characterization of the structure and dynamics of nucleic acids by NMR benefits significantly from position specifically labeled nucleotides. Here an E. coli strain deficient in the transketolase gene (tktA) and grown on glucose that is labeled at different carbon sites is shown to facilitate cost-effective and large scale production of useful nucleotides. These nucleotides are site specifically labeled in C1' and C5' with minimal scrambling within the ribose ring. To demonstrate the utility of this labeling approach, the new site-specific labeled and the uniformly labeled nucleotides were used to synthesize a 36-nt RNA containing the catalytically essential domain 5 (D5) of the brown algae group II intron self-splicing ribozyme. The D5 RNA was used in binding and relaxation studies probed by NMR spectroscopy. Key nucleotides in the D5 RNA that are implicated in binding Mg(2+) ions are well resolved. As a result, spectra obtained using selectively labeled nucleotides have higher signal-to-noise ratio compared to those obtained using uniformly labeled nucleotides. Thus, compared to the uniformly (13)C/(15)N-labeled nucleotides, these specifically labeled nucleotides eliminate the extensive (13)C-(13)C coupling within the nitrogenous base and ribose ring, give rise to less crowded and more resolved NMR spectra, and accurate relaxation rates without the need for constant-time or band-selective decoupled NMR experiments. These position selective labeled nucleotides should, therefore, find wide use in NMR analysis of biologically interesting RNA molecules.


Assuntos
Escherichia coli/genética , Marcação por Isótopo/métodos , Ressonância Magnética Nuclear Biomolecular/métodos , Nucleotídeos/biossíntese , RNA/metabolismo , Transcetolase/genética , Biomassa , Isótopos de Carbono , Escherichia coli/enzimologia , Escherichia coli/metabolismo , Glucose/química , Glucose/metabolismo , Mutação , Isótopos de Nitrogênio , Nucleotídeos/química , Phaeophyceae/genética , RNA/química , Auto-Splicing de RNA Ribossômico/química , Auto-Splicing de RNA Ribossômico/metabolismo , Transcetolase/metabolismo
16.
J Am Chem Soc ; 133(13): 4856-64, 2011 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-21384923

RESUMO

Recently, there has been an explosion of research activities in the cyclic dinucleotides field. Cyclic dinucleotides, such as c-di-GMP and c-di-AMP, have been shown to regulate bacterial virulence and biofilm formation. c-di-GMP can exist in different aggregate forms, and it has been demonstrated that the polymorphism of c-di-GMP is influenced by the nature of cation that is present in solution. In previous work, polymorphism of c-di-GMP could only be demonstrated at hundreds of micromolar concentrations of the dinucleotide, and it has been a matter of debate if polymorphism of c-di-GMP exists under in vivo conditions. In this Article, we demonstrate that c-di-GMP can form G-quadruplexes at low micromolar concentrations when aromatic molecules such as thiazole orange template the quadruplex formation. We then use this property of aromatic molecule-induced G-quadruplex formation of c-di-GMP to design a thiazole orange-based fluorescent detection of this important signaling molecule. We determine, using this thiazole orange assay on a crude bacterial cell lysate, that WspR D70E (a constitutively activated diguanylate cyclase) is functional in vivo when overexpressed in E. Coli . The intracellular concentration of c-di-GMP in an E. Coli cell that is overexpressed with WspR D70E is very high and can reach 2.92 mM.


Assuntos
Benzotiazóis/química , Biofilmes , GMP Cíclico/análogos & derivados , Fluorescência , Quadruplex G , Quinolinas/química , GMP Cíclico/análise , GMP Cíclico/síntese química , GMP Cíclico/química , Escherichia coli/química , Escherichia coli/citologia , Escherichia coli/metabolismo , Conformação Molecular
17.
ACS Biomater Sci Eng ; 7(3): 1031-1045, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33591713

RESUMO

This work introduces a thermally stable zwitterionic structure able to withstand steam sterilization as a general antifouling medical device interface. The sulfobetaine methacrylate (SBMA) monomer and its polymer form are among the most widely used zwitterionic materials. They are easy to synthesize and have good antifouling properties. However, they partially lose their properties after steam sterilization, a common procedure used to sterilize biomedical interfaces. In this study, ultrahigh-performance liquid chromatography/mass spectrometry (UHPLC-MS) was used to analyze and discuss the molecular structure of SBMA before and after a steam sterilization procedure, and a strategy to address the thermal stability issue proposed, using sulfobetaine methacrylamide (SBAA) instead of SBMA. Interestingly, it was found that the chemical structure of SBAA material can withstand the medical sterilization process at 121 °C while maintaining good antifouling properties, tested with proteins (fibrinogen), bacteria (Escherichia coli), and whole blood. On the other hand, SBMA gels failed at maintaining their excellent antifouling properties after sterilization. This study suggests that the SBAA structure can be used to replace SBMA in the bioinert interface of sterilizable medical devices, such as rayon fiber membranes used for disease control.


Assuntos
Betaína , Metacrilatos , Betaína/análogos & derivados , Polímeros , Esterilização
18.
Front Cell Dev Biol ; 9: 682561, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34179011

RESUMO

Thyroid carcinoma (TC) is the most common endocrine malignancy, and papillary TC (PTC) is the most frequent subtype of TC, accounting for 85-90% of all the cases. Aberrant histone acetylation contributes to carcinogenesis by inducing the dysregulation of certain cancer-related genes. However, the histone acetylation landscape in PTC remains elusive. Here, we interrogated the epigenomes of PTC and benign thyroid nodule (BTN) tissues by applying H3K27ac chromatin immunoprecipitation followed by deep sequencing (ChIP-seq) along with RNA-sequencing. By comparing the epigenomic features between PTC and BTN, we detected changes in H3K27ac levels at active regulatory regions, identified PTC-specific super-enhancer-associated genes involving immune-response and cancer-related pathways, and uncovered several genes that associated with disease-free survival of PTC. In summary, our data provided a genome-wide landscape of histone modification in PTC and demonstrated the role of enhancers in transcriptional regulations associated with prognosis of PTC.

19.
Genome Med ; 13(1): 146, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34493320

RESUMO

BACKGROUND: Epstein-Barr virus (EBV)-associated gastric carcinomas (EBVaGCs) present unique molecular signatures, but the tumorigenesis of EBVaGCs and the role EBV plays during this process remain poorly understood. METHODS: We applied whole-exome sequencing, EBV genome sequencing, and whole-genome bisulfite sequencing to multiple samples (n = 123) derived from the same patients (n = 25), which covered saliva samples and different histological stages from morphologically normal epithelial tissues to dysplasia and EBVaGCs. We compared the genomic landscape between EBVaGCs and their precursor lesions and traced the clonal evolution for each patient. We also analyzed genome sequences of EBV from samples of different histological types. Finally, the key molecular events promoting the tumor evolution were demonstrated by MTT, IC50, and colony formation assay in vitro experiments and in vivo xenograft experiments. RESULTS: Our analysis revealed increasing mutational burden and EBV load from normal tissues and low-grade dysplasia (LD) to high-grade dysplasia (HD) and EBVaGCs, and oncogenic amplifications occurred late in EBVaGCs. Interestingly, within each patient, EBVaGCs and HDs were monoclonal and harbored single-strain-originated EBV, but saliva or normal tissues/LDs had different EBV strains from that in EBVaGCs. Compared with precursor lesions, tumor cells showed incremental methylation in promotor regions, whereas EBV presented consistent hypermethylation. Dominant alterations targeting the PI3K-Akt and Wnt pathways were found in EBV-infected cells. The combinational inhibition of these two pathways in EBV-positive tumor cells confirmed their synergistic function. CONCLUSIONS: We portrayed the (epi) genomic evolution process of EBVaGCs, revealed the extensive genomic diversity of EBV between tumors and normal tissue sites, and demonstrated the synergistic activation of the PI3K and Wnt pathways in EBVaGCs, offering a new potential treatment strategy for this disease.


Assuntos
Carcinoma/genética , Infecções por Vírus Epstein-Barr/genética , Genômica , Herpesvirus Humano 4/genética , Neoplasias Gástricas/genética , Animais , Linhagem Celular Tumoral , Metilação de DNA , Infecções por Vírus Epstein-Barr/patologia , Infecções por Vírus Epstein-Barr/virologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mutação , Oncogenes , Fosfatidilinositol 3-Quinases/genética , Filogenia , Neoplasias Gástricas/patologia , Sequenciamento Completo do Genoma
20.
Anal Chim Acta ; 1093: 142-149, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31735207

RESUMO

α-amanitin is the most toxic amanita in mushrooms with lethal dose to humans around 0.1 mg. Kg-1. Hence, early identification of the poison would improve survival rates and prevent lethal poisoning cases. In this study, molecularly imprinted photonic crystal (MIPC) sensor was prepared by combining molecular imprinting with photonic crystal templates and tested towards the detection of α-amanitin. In this process, synthesized moiety of α-amanitin was utilized as template, dispersed SiO2 colloidal photonic crystal as carrier, methacrylic acid (MAA) as functional monomer, and ethylene glycol dimethacrylate (EDGMA) as crosslinker. The adsorption behavior of MIPC towards α-amanitin in ethanol solution showed shifts in diffraction peaks of MIPC upon binding with α-amanitin molecules. The reflection peak wavelength varied linearly with α-amanitin concentration according to the correlation formula: λ = 15.417c+489.17 (R2 = 0.9985). The recognition process was accompanied by gradual color change in MIPC film. The prepared MIPC sensor possessed wide linear range (10-9-10-3 mg L-1), change in visual color, low detection limit (10-10 mg L-1), short response time (2 min), and good reusability. The MIPC film was then tested towards the detection of α-amanitin in real biological samples (mushroom, urine, and serum) and showed reasonable shift in diffraction peaks and color change upon soaking in solutions spiked with α-amanitin at 10-6 mg L-1 and 10-3 mg L-1, suggesting the suitability of the film for the rapid identification of α-amanitin in complex sample matrices. Overall, the proposed sensor looks promising for the rapid identification of α-amanitin in clinical analysis and food poisoning.


Assuntos
Alfa-Amanitina/análise , Colorimetria/métodos , Dióxido de Silício/química , Agaricales/química , Alfa-Amanitina/sangue , Alfa-Amanitina/urina , Feminino , Humanos , Limite de Detecção , Impressão Molecular/métodos , Ácidos Polimetacrílicos/química , Reprodutibilidade dos Testes
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