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1.
Nat Commun ; 11(1): 4964, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009394

RESUMO

Thrombosis leads to platelet activation and subsequent degradation; therefore, replenishment of platelets from hematopoietic stem/progenitor cells (HSPCs) is needed to maintain the physiological level of circulating platelets. Platelet-derived microparticles (PMPs) are protein- and RNA-containing vesicles released from activated platelets. We hypothesized that factors carried by PMPs might influence the production of platelets from HSPCs, in a positive feedback fashion. Here we show that, during mouse acute liver injury, the density of megakaryocyte in the bone marrow increases following an increase in circulating PMPs, but without thrombopoietin (TPO) upregulation. In vitro, PMPs are internalized by HSPCs and drive them toward a megakaryocytic fate. Mechanistically, miR-1915-3p, a miRNA highly enriched in PMPs, is transported to target cells and suppresses the expression levels of Rho GTPase family member B, thereby inducing megakaryopoiesis. In addition, direct injection of PMPs into irradiated mice increases the number of megakaryocytes and platelets without affecting TPO levels. In conclusion, our data reveal that PMPs have a role in promoting megakaryocytic differentiation and platelet production.


Assuntos
Plaquetas/metabolismo , Diferenciação Celular , Micropartículas Derivadas de Células/metabolismo , Megacariócitos/citologia , MicroRNAs/metabolismo , Animais , Sequência de Bases , Linhagem Celular , Endocitose , Perfilação da Expressão Gênica , Humanos , Fígado/lesões , Fígado/patologia , Masculino , Megacariócitos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , MicroRNAs/genética , Poliploidia , Proteína rhoB de Ligação ao GTP/metabolismo
2.
Medicine (Baltimore) ; 99(35): e21996, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32871952

RESUMO

It is of significance to evaluate central lymph node status in patients with papillary thyroid carcinoma (PTC), because it can decrease postoperative complications resulting from unnecessary prophylactic central lymph node dissection (CLND). Due to the low sensitivity and specificity of neck ultrasonography in the evaluation of central lymph node metastasis (CLNM), it is urgently required to find alternative biomarkers to predict CLNM in PTC patients, which is the main purpose of this study.RNA-sequencing datasets and clinical data of 506 patients with thyroid carcinoma from the Cancer Genome Atlas (TCGA) database were downloaded and analyzed to identify differentially expressed miRNAs (DEMs), which can independently predict CLNM in PTC. A nomogram predictive of CLNM was developed based on clinical characteristics and the identified miRNAs. Receiver operating characteristics curves were drawn to evaluate the predictive performance of the nomogram. Bioinformatics analyses, including target genes identification, functional enrichment analysis, and protein-protein interaction network, were performed to explore the potential roles of the identified DEMs related to CLNM in PTC.A total of 316 PTC patients were included to identify DEMs. Two hundred thirty-seven (75%) PTC patients were randomly selected from the 316 patients as a training set, while the remaining 79 (25%) patients were regarded as a testing set for validation. Two DEMs, miRNA-146b-3p (HR: 1.327, 95% CI = 1.135-1.551, P = .000) and miRNA-363-3p (HR: 0.714, 95% CI = 0.528-0.966, P = .029), were significantly associated with CLNM. A risk score based on these 2 DEMs and calculating from multivariate logistic regression analysis, was significantly lower in N0 group over N1a group in both training (N0 vs N1a: 2.04 ±â€Š1.01 vs 2.73 ±â€Š0.61, P = .000) and testing (N0 vs N1a: 2.20 ±â€Š0.93 vs 2.79 ±â€Š0.68, P = .003) sets. The nomogram including risk score, age, and extrathyroidal extension (ETE) was constructed in the training set and was then validated in the testing set, which showed better prediction value than the other three predictors (risk score, age, and ETE) in terms of CLNM identification. Bioinformatics analyses revealed that 5 hub genes, SLC6A1, SYT1, COL19A1, RIMS2, and COL1A2, might involve in pathways including extracellular matrix organization, ion transmembrane transporter activity, axon guidance, and ABC transporters.On the basis of this study, the nomogram including risk score, age, and ETE showed good prediction of CLNM in PTC, which has a potential to facilitate individualized decision for surgical plans.


Assuntos
Metástase Linfática , MicroRNAs/metabolismo , Nomogramas , Câncer Papilífero da Tireoide/metabolismo , Mineração de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mapas de Interação de Proteínas , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/patologia
3.
Medicine (Baltimore) ; 99(35): e22045, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32871962

RESUMO

BACKGROUND: Previous studies have reported that microRNA-21 (mRNA-21) has an effect on the prognosis of pancreatic cancer. However, the conclusion is still unclear. Therefore, this study will try to explore the effect of high expression of mRNA-21 on the prognosis of pancreatic cancer. METHODS: Retrieved the database, including the China National Knowledge Infrastructure (CNKI), Chinese Biomedical literature Database (CBM), Chinese Scientific and Journal Database (VIP), Wan Fang database, PubMed, and EMBASE. Hazard ratios (HRs) and its 95% confidence intervals (CIs) to assess the prognostic effect of miRNA-21 on overall survival (OS) and disease-free survival (DFS). RevMan 5.3 and STATA 16.0 software were used to perform the meta-analysis. RESULTS: This study will comprehensively review and evaluate the available evidence of high expression of miRNA-21 on the prognosis of patients with pancreatic cancer. CONCLUSION: Our findings will show the effect of high expression of miRNA-21 on the prognosis of patients with pancreatic cancer. Such studies may find a new prognostic marker for patients with pancreatic cancer and help clinicians and health professionals make clinical decisions. ETHICS AND DISSEMINATION: The private information from individuals will not publish. This systematic review also will not involve endangering participant rights. Ethical approval is not available. The results may be published in a peer- reviewed journal or disseminated in relevant conferences. OSF REGISTRATION NUMBER: DOI 10.17605/OSF.IO/2A6KJ.


Assuntos
MicroRNAs/metabolismo , Neoplasias Pancreáticas/metabolismo , Humanos , Metanálise como Assunto , Neoplasias Pancreáticas/diagnóstico , Prognóstico , Revisões Sistemáticas como Assunto
4.
Medicine (Baltimore) ; 99(35): e22047, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32871963

RESUMO

BACKGROUND: We identified the hub genes and pathways dysregulated in acute myeloid leukemia and the potential molecular mechanisms involved. METHODS: We downloaded the GSE15061 gene expression dataset from the Gene Expression Omnibus database and used weighted gene co-expression network analysis to identify hub genes. Differential expression of the genes was evaluated using the limma package in R software. Subsequently, we built a protein-protein interaction network followed by functional enrichment analysis. Then, the prognostic significance of gene expression was explored in terms of overall survival. Finally, transcription factor-mRNA (ribonucleic acid) and microRNA-mRNA interaction analysis was also explored. RESULTS: We identified 100 differentially expressed hub genes. Functional enrichment analysis indicated that the genes were principally involved in immune system regulation, host defense, and negative regulation of apoptosis and myeloid cell differentiation. We identified 4 hub genes, the expression of which was significantly correlated with overall survival. Finally, 26 key regulators for hub genes and 38 microRNA-mRNA interactions were identified. CONCLUSION: We performed a comprehensive bioinformatics analysis of hub genes potentially involved in acute myeloid leukemia development. Further molecular biological experiments are required to confirm the roles played by these genes.


Assuntos
Leucemia Mieloide Aguda/metabolismo , Biologia Computacional , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , MicroRNAs/metabolismo , Mapas de Interação de Proteínas , Análise de Sobrevida , Fatores de Transcrição/metabolismo , Transcriptoma
5.
Yonsei Med J ; 61(9): 750-761, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32882759

RESUMO

PURPOSE: Gastric cancer (GC) is a malignant tumor with a high mortality rate. Drug resistance is a major obstacle to GC therapy. This study aimed to investigate the role and mechanism of exosomal circPRRX1 in doxorubicin resistance in GC. MATERIALS AND METHODS: HGC-27 and AGS cells were exposed to different doses of doxorubicin to construct doxorubicin-resistant cell lines. Levels of circPRRX1, miR-3064-5p, and nonreceptor tyrosine phosphatase 14 (PTPN14) were detected by quantitative real-time PCR or Western blot assay. Then, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide, transwell, and Western blot assays were used to explore the function of circPRRX1 in GC cells. Interactions among circPRRX1, miR-3064-5p, and PTPN14 were confirmed by dual-luciferase reporter assay. The in vivo function of circPRRX1 was analyzed in a xenograft tumor model. RESULTS: CircPRRX1 was highly expressed in doxorubicin-resistant GC cell lines. Knockdown of circPRRX1 reversed doxorubicin resistance in doxorubicin-resistant GC cells. Additionally, extracellular circPRRX1 was carried by exosomes to spread doxorubicin resistance. CircPRRX1 silencing reduced doxorubicin resistance by targeting miR-3064-5p or regulating PTPN14. In GC patients, high levels of circPRRX1 in serum exosomes were associated with poor responses to doxorubicin treatment. Moreover, depletion of circPRRX1 reduced doxorubicin resistance in vivo. CONCLUSION: CircPRRX1 strengthened doxorubicin resistance by modulating miR-3064-5p/PTPN14 signaling and might be a therapeutic target for GC patients.


Assuntos
Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , MicroRNAs/genética , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Linhagem Celular Tumoral , Exossomos/genética , Exossomos/metabolismo , Exossomos/patologia , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio , Humanos , MicroRNAs/metabolismo , Proteínas Tirosina Fosfatases não Receptoras/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia
6.
Yonsei Med J ; 61(9): 780-788, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32882762

RESUMO

PURPOSE: This research was designed to investigate how miR-542-5p regulates the progression of hyperglycemia and hyperlipoidemia. MATERIALS AND METHODS: An in vivo model with diabetic db/db mice and an in vitro model with forskolin/dexamethasone (FSK/DEX)-induced primary hepatocytes and HepG2 cells were employed in the study. Bioinformatics analysis was conducted to identify the expression of candidate miRNAs in the liver tissues of diabetic and control mice. H&E staining revealed liver morphology in diabetic and control mice. Pyruvate tolerance tests, insulin tolerance tests, and intraperitoneal glucose tolerance test were utilized to assess insulin resistance. ELISA was conducted to evaluate blood glucose and insulin levels. Red oil O staining showed lipid deposition in liver tissues. Luciferase reporter assay was used to depict binding between miR-542-5p and forkhead box O1 (FOXO1). RESULTS: MiR-542-5p expression was under-expressed in the livers of db/db mice. Further in vitro experiments revealed that FSK/DEX, which mimics the effects of glucagon and glucocorticoids, induced cellular glucose production in HepG2 cells and in primary hepatocytes cells. Notably, these changes were reversed by miR-542-5p. We found that transcription factor FOXO1 is a target of miR-542-5p. Further in vivo study indicated that miR-542-5p overexpression decreases FOXO1 expression, thereby reversing increases in blood glucose, blood lipids, and glucose-related enzymes in diabetic db/db mice. In contrast, anti-miR-542-5p exerted an adverse influence on blood glucose and blood lipid metabolism, and its stimulatory effects were significantly inhibited by sh-FOXO1 in normal control mice. CONCLUSION: Collectively, our results indicated that miR-542-5p inhibits hyperglycemia and hyperlipoidemia by targeting FOXO1.


Assuntos
Diabetes Mellitus Tipo 2/genética , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Hiperglicemia/tratamento farmacológico , Hiperlipidemias/tratamento farmacológico , MicroRNAs/genética , Animais , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Regulação da Expressão Gênica , Glucose/metabolismo , Teste de Tolerância a Glucose , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Hiperglicemia/metabolismo , Hiperlipidemias/metabolismo , Resistência à Insulina , Metabolismo dos Lipídeos , Fígado/metabolismo , Camundongos , MicroRNAs/metabolismo , MicroRNAs/farmacologia
7.
BMC Bioinformatics ; 21(1): 401, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32912137

RESUMO

BACKGROUND: As an important non-coding RNA, microRNA (miRNA) plays a significant role in a series of life processes and is closely associated with a variety of Human diseases. Hence, identification of potential miRNA-disease associations can make great contributions to the research and treatment of Human diseases. However, to our knowledge, many existing computational methods only utilize the single type of known association information between miRNAs and diseases to predict their potential associations, without focusing on their interactions or associations with other types of molecules. RESULTS: In this paper, we propose a network embedding-based method for predicting miRNA-disease associations by preserving behavior and attribute information. Firstly, a heterogeneous network is constructed by integrating known associations among miRNA, protein and disease, and the network representation method Learning Graph Representations with Global Structural Information (GraRep) is implemented to learn the behavior information of miRNAs and diseases in the network. Then, the behavior information of miRNAs and diseases is combined with the attribute information of them to represent miRNA-disease association pairs. Finally, the prediction model is established based on the Random Forest algorithm. Under the five-fold cross validation, the proposed NEMPD model obtained average 85.41% prediction accuracy with 80.96% sensitivity at the AUC of 91.58%. Furthermore, the performance of NEMPD is also validated by the case studies. Among the top 50 predicted disease-related miRNAs, 48 (breast neoplasms), 47 (colon neoplasms), 47 (lung neoplasms) were confirmed by two other databases. CONCLUSIONS: The proposed NEMPD model has a good performance in predicting the potential associations between miRNAs and diseases, and has great potency in the field of miRNA-disease association prediction in the future.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias do Colo/diagnóstico , Biologia Computacional/métodos , Neoplasias Pulmonares/diagnóstico , MicroRNAs/metabolismo , Algoritmos , Área Sob a Curva , Neoplasias da Mama/genética , Neoplasias do Colo/genética , Feminino , Humanos , Neoplasias Pulmonares/genética , MicroRNAs/genética , Curva ROC
8.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 32(8): 938-942, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32912406

RESUMO

OBJECTIVE: To analyze the relationship between the expression of microRNA-126 (miR-126) in peripheral blood lymphocytes with apoptosis and prognosis in patients with sepsis, and to explore its potential regulatory mechanism. METHODS: Thirty patients with general infection and 20 patients with sepsis admitted to the department of intensive care unit (ICU) of the First Affiliated Hospital of Bengbu Medical College from January to December 2019 were enrolled. Peripheral blood was taken to separate lymphocytes, and the expressions of miR-126 and caspase-3 were detected by reverse transcription-polymerase chain reaction (RT-PCR). At the same time, the liver and kidney function and other laboratory indexes were measured, and the sequential organ failure assessment (SOFA) and acute physiology and chronic health evaluation II (APACHE II) scores were calculated. The 28-day prognosis was observed. Pearson method was used to analyze the correlation between miR-126 and caspase-3, APACHE II score. Receiver operating characteristic (ROC) curve was used to analyze the predictive value of miR-126 on prognosis; at the same time, according to the best cut-off value of miR-126 in predicting prognosis, the patients were divided into two groups, and the 28-day Kaplan-Meier survival curve was drawn. RESULTS: The expression of miR-126 in peripheral blood lymphocytes of patients with sepsis was lower than that of patients with general infection [miR-126 mRNA (2-ΔΔCt): 1.239±0.134 vs. 1.599±0.110, P < 0.01], while the expression of caspase-3 and APACHE II score were significantly increased [caspase-3 mRNA (2-ΔΔCt): 1.172±0.132 vs. 0.901±0.143, APACHE II: 19.75±3.74 vs. 12.63±3.94, both P < 0.01]. Pearson correlation analysis showed that the expression of miR-126 was negatively correlated with the expression of caspase-3 (r = -0.678, P < 0.001) and APACHE II score (r = -0.581, P < 0.001). ROC curve analysis showed that the area under the ROC curve (AUC) for predicting the prognosis by miR-126 expression in peripheral blood lymphocytes was 0.823 (P < 0.001). When the best cut-off value was 1.395, the sensitivity was 75.0%, the specificity was 71.4%, the positive predictive value was 81.1%, the negative predictive value was 63.6%, the positive likelihood ratio was 2.622, and the negative likelihood ratio 0.350. In addition, the patients were divided into high miR-126 group (miR-126 > 1.395, n = 31) and low miR-126 group (miR-126 ≤ 1.395, n = 19) according to the best cut-off value of miR-126. Kaplan-Meier survival curve analysis showed that the 28-day cumulative survival rate of high miR-126 group was higher than that of low miR-126 group (Log-Rank: χ2 = 11.702, P = 0.001). CONCLUSIONS: miR-126 in peripheral blood lymphocytes of patients with sepsis may affect immune status by promoting apoptosis of lymphocytes, and its expression level can reflect the severity and prognosis of sepsis.


Assuntos
MicroRNAs/metabolismo , Sepse , Apoptose , Humanos , Linfócitos , Prognóstico
9.
BMC Bioinformatics ; 21(1): 396, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32894041

RESUMO

BACKGROUND: MicroRNAs are a class of important small noncoding RNAs, which have been reported to be involved in the processes of tumorigenesis and development by targeting a few genes. Existing studies show that the imbalance between cell proliferation and apoptosis is closely related to the initiation and development of cancers. However, the impact of miRNAs on this imbalance has not been studied systematically. RESULTS: In this study, we first construct a cell fate miRNA-gene regulatory network. Then, we propose a systematical method for calculating the global impact of miRNAs on cell fate genes based on the shortest path. Results on breast cancer and liver cancer datasets show that most of the cell fate genes are perturbed by the differentially expressed miRNAs. Most of the top-identified miRNAs are verified in the Human MicroRNA Disease Database (HMDD) and are related to breast and liver cancers. Function analysis shows that the top 20 miRNAs regulate multiple cell fate related function modules and interact tightly based on their functional similarity. Furthermore, more than half of them can promote sensitivity or induce resistance to some anti-cancer drugs. Besides, survival analysis demonstrates that the top-ranked miRNAs are significantly related to the overall survival time in the breast and liver cancers group. CONCLUSION: In sum, this study can help to systematically study the important role of miRNAs on proliferation and apoptosis and thereby uncover the key miRNAs during the process of tumorigenesis. Furthermore, the results of this study will contribute to the development of clinical therapy based miRNAs for cancers.


Assuntos
Apoptose/genética , Proliferação de Células/genética , MicroRNAs/metabolismo , Biomarcadores/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Bases de Dados Genéticas , Feminino , Redes Reguladoras de Genes , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , MicroRNAs/genética , RNA Mensageiro/metabolismo , Análise de Sobrevida
10.
DNA Cell Biol ; 39(10): 1779-1788, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32865424

RESUMO

Today, mesenchymal stem cells (MSCs) are candidates for various autoimmune disease treatments due to immunomodulatory activity in these cells. Much research has recently been done to improve the immunomodulatory activity of MSCs. Genetic variation is one of these methods. microRNAs (miRNAs) are small noncoding RNAs that control most of the cell's biological activities. Recent studies have shown that miRNAs play a significant role in the regulation of MSC immunomodulatory activity. Pomegranate is a fruit that has antioxidant, anti-inflammatory, and anticancer properties and has been used for many years for therapeutic purposes. The objective of this research is to evaluate the immunoregulatory-related miRNAs level of adipose-derived MSCs (Ad-MSCs) obtained from adipose tissue in the presence or lack of pomegranate (Punica granatum) extract (PGE). Our results showed that miRNA-23 and miRNA-126 were upregulated by PGE treatment in MSCs, and in contrast, miRNA-21 and miRNA-155 were downregulated by PGE treatment in MSCs. In addition this research shows that PGE can downregulate the expression of PI3K\AKT1\NF-[Formula: see text]B in Ad-MSCs. Our bioinformatics data have shown that the target of these four miRNAs and the signaling pathways, in which these targets are involved, can play an important role in regulating the immunomodulation function of stem cells. In conclusion, PGE can inhibit the expression of PI3K\AKT1\NF-[Formula: see text]B genes involved in inflammatory pathways via miRNA-23 and miRNA-126 overexpression or miRNA-21 and miRNA-155 downregulation that plays a role in the pathways of immune modulation in Ad-MSCs. These results may provide insight into the mechanism underlying the regulation of the immunomodulatory activity of Ad-MSCs by PGE.


Assuntos
Anti-Inflamatórios/farmacologia , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Extratos Vegetais/farmacologia , Células Cultivadas , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , MicroRNAs/genética , NF-kappa B/genética , Fosfatidilinositol 3-Quinases/genética , Romã (Fruta)/química , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
11.
DNA Cell Biol ; 39(10): 1895-1906, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32882141

RESUMO

Acute aortic dissection (AD) is one of the most severe and highly mortality vascular disease. Its actual prevalence may be seriously underestimated. We studied different expression genes to understand gene profile change between acute AD and nondiseased individuals, and then discover potential biomarkers and therapeutic targets of acute AD. In our study, acute AD differentially expressed mRNAs and miRNAs were identified through bioinformatics analysis on Gene Expression Omnibus data sets GSE52093, GSE98770, and GSE92427. Then, comprehensive target prediction and network analysis methods were used to evaluate protein-protein interaction networks and to identify Gene Ontology terms for differentially expressed mRNAs. Differentially expressed mRNAs-miRNAs involved in acute AD were assessed as well. Finally, the quantitative real-time PCR and in vitro experiment was used to validate the results. We found Integral Membrane Protein 2C (ITM2C) was low expressed and miR-107-5p was highly expressed in acute AD tissues. Meanwhile, overexpression miR-107-5p promoted the cell proliferation and inhibited the cell apoptosis in RASMC cells. miR-107-5p inhibited the progression of acute AD through targeted ITM2C.


Assuntos
Aneurisma Dissecante/genética , MicroRNAs/genética , Aneurisma Dissecante/metabolismo , Aneurisma Dissecante/patologia , Animais , Apoptose , Biomarcadores/metabolismo , Proliferação de Células , Células Cultivadas , Redes Reguladoras de Genes , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , MicroRNAs/metabolismo , Miócitos de Músculo Liso/metabolismo , Mapas de Interação de Proteínas , Ratos , Transcriptoma
12.
Life Sci ; 259: 118387, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32890603

RESUMO

Telomerase is a nucleoprotein reverse transcriptase that maintains the telomere, a protective structure at the ends of the chromosome, and is active in cancer cells, stem cells, and fetal cells. Telomerase immortalizes cancer cells and induces unlimited cell division by preventing telomere shortening. Immortalized cancer cells have unlimited proliferative potential due to telomerase activity that causes tumorigenesis and malignancy. Therefore, telomerase can be a lucrative anti-cancer target. The regulation of catalytic subunit of telomerase (TERT) determines the extent of telomerase activity. miRNAs, as an endogenous regulator of gene expression, can control telomerase activity by targeting TERT mRNA. miRNAs that have a decreasing effect on TERT translation mediate modulation of telomerase activity in cancer cells by binding to TERT mRNA and regulating TERT translation. In this review, we provide an update on miRNAs that influence telomerase activity by regulation of TERT translation.


Assuntos
MicroRNAs/metabolismo , Neoplasias/enzimologia , Telomerase/metabolismo , Animais , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/metabolismo
13.
Medicine (Baltimore) ; 99(36): e21653, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32898999

RESUMO

The expression profile and specific roles of microRNAs (miRNAs) in regulation of atrophic bone nonunion are not fully understood. Here, we present evidence that miRNAs are involved in regulation of several osteogenic genes and may contribute to the development of atrophic bone nonunion.The miRNA expression profile of repairing tissues in atrophic bone nonunion patients (group A) and in callus tissues from patients with healed fractures (group B) were quantitatively measured. microRNA microarrays were used to identify differentially expressed miRNAs, and the bioinformatics methods were used to predict the potential target genes. Quantitative real-time polymerase chain reaction (qRT-PCR), western blot, and dual-luciferase reporter assay were performed in human bone marrow stromal cells (hBMSCs) to validate the microarray results.Nine miRNAs in group A were up-regulated 1.5 times compared to group B, while the other 9 miRNAs in group A were down-regulated 1.5 times. Several target regions of these miRNAs were identified in the osteogenic genes, as well as in the other genes in their families or related regulatory factors. Four miRNAs (hsa-miR-149, hsa-miR-221, hsa-miR-628-3p, and hsa-miR-654-5p) could play important roles in regulating bone nonunion development. hBMSCs transfected with these miRNAs significantly decreased mRNA levels of alkaline phosphatase, liver/bone/kidney (ALPL), platelet derived growth factor subunit A (PDGFA), and bone morphogenetic protein 2 (BMP2). Lower protein expression levels were observed using western blotting, confirming that ALPL, PDGFA, and BMP2 were directly targeted by hsa-miR-149, hsa-miR-221, and hsa-miR-654-5p, respectively.In summary, hsa-miR-149, hsa-miR-221, and hsa-miR-654-5p may play important biological roles by repressing osteogenic target genes ALPL, PDGFA, and BMP2, and, therefore, contributing to progression of atrophic bone nonunion.


Assuntos
Osso e Ossos/metabolismo , Fraturas do Fêmur/genética , Fraturas do Úmero/genética , MicroRNAs/metabolismo , Fraturas da Tíbia/genética , Adulto , Criança , Feminino , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Masculino , Regulação para Cima
14.
Nat Commun ; 11(1): 4551, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917870

RESUMO

Circular RNAs (circRNAs) have recently gained substantial attention in the cancer research field where most, including the putative oncogene ciRS-7 (CDR1as), have been proposed to function as competitive endogenous RNAs (ceRNAs) by sponging specific microRNAs. Here, we report the first spatially resolved cellular expression patterns of ciRS-7 in colon cancer and show that ciRS-7 is completely absent in the cancer cells, but highly expressed in stromal cells within the tumor microenvironment. Additionally, our data suggest that this generally apply to classical oncogene-driven adenocarcinomas, but not to other cancers, including malignant melanoma. Moreover, we find that correlations between circRNA and mRNA expression, which are commonly interpreted as evidence of a ceRNA function, can be explained by different cancer-to-stromal cell ratios among the studied tumor specimens. Together, these results have wide implications for future circRNA studies and highlight the importance of spatially resolving expression patterns of circRNAs proposed to function as ceRNAs.


Assuntos
Neoplasias do Colo/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , RNA Circular/metabolismo , RNA Longo não Codificante/metabolismo , Microambiente Tumoral/genética , Idoso , Neoplasias do Colo/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oncogenes/genética , Estudos Prospectivos , RNA Circular/genética , RNA Longo não Codificante/genética , Análise Espacial
15.
Nat Commun ; 11(1): 4798, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32968066

RESUMO

Myeloid cells are known mediators of hypertension, but their role in initiating renin-induced hypertension has not been studied. Vitamin D deficiency causes pro-inflammatory macrophage infiltration in metabolic tissues and is linked to renin-mediated hypertension. We tested the hypothesis that impaired vitamin D signaling in macrophages causes hypertension using conditional knockout of the myeloid vitamin D receptor in mice (KODMAC). These mice develop renin-dependent hypertension due to macrophage infiltration of the vasculature and direct activation of renal juxtaglomerular (JG) cell renin production. Induction of endoplasmic reticulum stress in knockout macrophages increases miR-106b-5p secretion, which stimulates JG cell renin production via repression of transcription factors E2f1 and Pde3b. Moreover, in wild-type recipient mice of KODMAC/miR106b-/- bone marrow, knockout of miR-106b-5p prevents the hypertension and JG cell renin production induced by KODMAC macrophages, suggesting myeloid-specific, miR-106b-5p-dependent effects. These findings confirm macrophage miR-106b-5p secretion from impaired vitamin D receptor signaling causes inflammation-induced hypertension.


Assuntos
Hipertensão Renal/metabolismo , Hipertensão/metabolismo , Macrófagos/metabolismo , MicroRNAs/metabolismo , Nefrite/metabolismo , Renina/metabolismo , Animais , Medula Óssea , Transplante de Medula Óssea , Modelos Animais de Doenças , Fator de Transcrição E2F1/metabolismo , Estresse do Retículo Endoplasmático , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Mieloides , Receptores de Calcitriol , Vitamina D
16.
Nat Commun ; 11(1): 4825, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32973178

RESUMO

Short regulatory RNA molecules underpin gene expression and govern cellular state and physiology. To establish an alternative layer of control over these processes, we generated chimeric regulatory RNAs that interact reversibly and light-dependently with the light-oxygen-voltage photoreceptor PAL. By harnessing this interaction, the function of micro RNAs (miRs) and short hairpin (sh) RNAs in mammalian cells can be regulated in a spatiotemporally precise manner. The underlying strategy is generic and can be adapted to near-arbitrary target sequences. Owing to full genetic encodability, it establishes optoribogenetic control of cell state and physiology. The method stands to facilitate the non-invasive, reversible and spatiotemporally resolved study of regulatory RNAs and protein function in cellular and organismal environments.


Assuntos
Expressão Gênica , Células Fotorreceptoras/metabolismo , RNA/metabolismo , Animais , Células HEK293 , Humanos , MicroRNAs/metabolismo , RNA/genética , RNA Interferente Pequeno
17.
Int J Mol Sci ; 21(19)2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32993015

RESUMO

The outbreak of a novel coronavirus SARS-CoV-2 responsible for the COVID-19 pandemic has caused a worldwide public health emergency. Due to the constantly evolving nature of the coronaviruses, SARS-CoV-2-mediated alterations on post-transcriptional gene regulations across human tissues remain elusive. In this study, we analyzed publicly available genomic datasets to systematically dissect the crosstalk and dysregulation of the human post-transcriptional regulatory networks governed by RNA-binding proteins (RBPs) and micro-RNAs (miRs) due to SARS-CoV-2 infection. We uncovered that 13 out of 29 SARS-CoV-2-encoded proteins directly interacted with 51 human RBPs, of which the majority of them were abundantly expressed in gonadal tissues and immune cells. We further performed a functional analysis of differentially expressed genes in mock-treated versus SARS-CoV-2-infected lung cells that revealed enrichment for the immune response, cytokine-mediated signaling, and metabolism-associated genes. This study also characterized the alternative splicing events in SARS-CoV-2-infected cells compared to the control, demonstrating that skipped exons and mutually exclusive exons were the most abundant events that potentially contributed to differential outcomes in response to the viral infection. A motif enrichment analysis on the RNA genomic sequence of SARS-CoV-2 clearly revealed the enrichment for RBPs such as SRSFs, PCBPs, ELAVs, and HNRNPs, suggesting the sponging of RBPs by the SARS-CoV-2 genome. A similar analysis to study the interactions of miRs with SARS-CoV-2 revealed functionally important miRs that were highly expressed in immune cells, suggesting that these interactions may contribute to the progression of the viral infection and modulate the host immune response across other human tissues. Given the need to understand the interactions of SARS-CoV-2 with key post-transcriptional regulators in the human genome, this study provided a systematic computational analysis to dissect the role of dysregulated post-transcriptional regulatory networks controlled by RBPs and miRs across tissue types during a SARS-CoV-2 infection.


Assuntos
Betacoronavirus/genética , Betacoronavirus/metabolismo , Infecções por Coronavirus/virologia , Redes Reguladoras de Genes , MicroRNAs/genética , Pneumonia Viral/virologia , Processamento Pós-Transcricional do RNA , Proteínas de Ligação a RNA/metabolismo , Regulação da Expressão Gênica , Genoma Viral , Humanos , MicroRNAs/metabolismo , Pandemias , Mapas de Interação de Proteínas , Proteínas de Ligação a RNA/genética
18.
Yonsei Med J ; 61(8): 660-669, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32734729

RESUMO

PURPOSE: Neonatal hypoxic ischemic encephalopathy (HIE) is an essential factor underlying neonatal death and disability. This study sought to explore the role of miR-146b-5p in regulating neonatal HIE. MATERIALS AND METHODS: In vitro and in vivo HIE models were established in PC12 cells and 10-day neonatal Sprague Dawley rats, respectively. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to assess miR-146b-5p expression and inflammatory factors [interleukin (IL)-6 and tumor necrosis factor (TNF)-α] in brain lesions and PC12 cells, while enzyme-linked immunosorbent assay was employed to detect the expression of oxidative stress factors (SOD and GSH-Px). Gain- and loss-assays of miR-146b-5p were conducted to verify its role in modulating the viability and apoptosis of PC12 cells under oxygen-glucose deprivation (OGD) treatment. Expression of TLR4, IRAK1, TRAF6, TAK1, and NF-κB were examined by qRT-PCR and/or Western blot. Dual luciferase activity assay was conducted to identify relationships between miR-146b-5p and IRAK1. RESULTS: In the HIE models, significant oxidative stress and inflammatory responses emerged upon upregulation of TLR4/IRAK1/TRAF6/TAK1/NF-κB signaling. Overexpression of miR-146b-5p greatly inhibited OGD-induced PC12 cell injury, inflammatory responses, and oxidative stress. Inhibiting miR-146b-5p, however, had the opposite effects. IRAK1 was found to be a target of miR-146b-5p, and miR-146b-5p overexpression suppressed the activation of IRAK1/TRAF6/TAK1/NF-κB signaling. CONCLUSION: This study demonstrated that miR-146b-5p overexpression alleviates HIE-induced neuron injury by inhibiting the IRAK1/TRAF6/TAK1/NF-κB pathway.


Assuntos
Hipóxia-Isquemia Encefálica/genética , Quinases Associadas a Receptores de Interleucina-1/metabolismo , MAP Quinase Quinase Quinases/metabolismo , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Fator 6 Associado a Receptor de TNF/metabolismo , Animais , Animais Recém-Nascidos , Apoptose/genética , Sequência de Bases , Modelos Animais de Doenças , Regulação para Baixo/genética , Glucose/deficiência , Inflamação/patologia , MicroRNAs/genética , Estresse Oxidativo , Oxigênio , Células PC12 , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
19.
Sheng Wu Gong Cheng Xue Bao ; 36(7): 1395-1404, 2020 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-32748597

RESUMO

By inserting microRNAs into the intron of EF1α promoter, we constructed a novel lentiviral vector knocking down PD-1 gene via microRNA and applied it to CAR-T cells. Lentiviral transduction efficiency and PD-1-silencing efficiency were detected by flow cytometry. PD-1 expression was detected by Western blotting. Relative expression of microRNA was measured by Q-PCR. Cytotoxicity of CAR-T cells based on this vector was tested by luciferase bioluminescence and flow cytometry. Compared with lentiviral vector with microRNA transcribed by U6 promotor, the transduction efficiency of lentiviral vector with microRNA which was inserted into the intron of EF1α promoter was more significant, and the knockdown rate of PD-1 was more than 90%, which was validated by flow cytometry and Western blotting. And the relative expression level of microRNA in Jurkat cells transduced with this novel lentiviral vector was shown by Q-PCR. Compared with normal CAR-T cells, CAR-T cells based on this vector showed stronger cytotoxicity against PD-L1 positive Raji cells. We successfully constructed a novel lentiviral vector that knocked down PD-1 via microRNA and verified the superiority of its transduction efficiency and knockdown efficiency of PD-1. CAR-T cells based on this vector can exert a more powerful cytotoxicity, thus providing theoretical support for the subsequent treatment of PD-L1 positive tumors.


Assuntos
Vetores Genéticos , Lentivirus , MicroRNAs , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Vetores Genéticos/genética , Humanos , Lentivirus/genética , MicroRNAs/metabolismo , Receptor de Morte Celular Programada 1 , Regiões Promotoras Genéticas/genética
20.
Mem Inst Oswaldo Cruz ; 115: e200238, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756740

RESUMO

BACKGROUND Paracoccidioides spp. causes paracoccidioidomycosis (PCM), an important and frequent systemic mycosis that occurs in Latin America. The infectious process begins with contact between the fungus and lung cells, and the molecular pattern of this interaction is currently poorly understood. MicroRNAs (miRNAs) are small non-coding RNAs that regulate the gene expression in many biological processes, including in the infections. OBJECTIVE This study aimed to analyse the expression of miRNAs in lung cells as response to infection by Paracoccidioides spp. METHODS A quantitative real-time polymerase chain reaction (RT-qPCR) based screening was employed to verify differentially expressed miRNAs in human lung cells infected with three different species; Paracoccidioides lutzii, Paracoccidioides americana, and Paracoccidioides brasiliensis. Furthermore, the in silico predictions of target genes and pathways for miRNAs were obtained. FINDINGS The results showed that miRNAs identified in the lung cells were different according to the species studied. However, based on the predicted targets, the potential signaling pathways regulated by miRNAs are common and related to adhesion, actin cytoskeleton rearrangement, apoptosis, and immune response mediated by T cells and TGF-ß. MAIN CONCLUSIONS In summary, this study showed the miRNAs pattern of epithelial cells in response to infection by Paracoccidioides species and the potential role of these molecules in the regulation of key pathogenesis mechanisms of PCM.


Assuntos
MicroRNAs , Paracoccidioides , Paracoccidioidomicose , Humanos , América Latina , Pulmão/citologia , MicroRNAs/metabolismo , Paracoccidioides/patogenicidade , Reação em Cadeia da Polimerase em Tempo Real
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