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陈劼 《重庆医学》2015,(17):2389-2391
目的 通过Meta分析已报道文献中的微小RNA-21(microRNA-21,miR-21)对肺癌的诊断价值,探讨血液中的miR-21对肺癌的诊断价值.方法 检索中国知网、维普、万方、PubMed和Embsase等数据库,按照已定的纳入和排出标准筛选文献.采用Quadas量表评估纳入文献质量.通过Stata12和Meta-Disc软件合并纳入文献的诊断值并检测评估异质性和发表偏倚.结果 共检出994篇相关文献,通过筛选,7篇文献(含1 088例样本)纳入本次Meta分析.通过合并文献得出,miR-21对肺癌的诊断灵敏度、特异度、阳性似然比、和阴性似然分别为0.68(95%CI:0.55~0.79),0.82(95%CI:0.76~0.86),3.70(95%CI:2.60~5.25)和0.39(95%CI:0.27~0.58);综合诊断指标综合曲线下面积(SROC)和诊断比值比(DOR)分别为0.84(95%CI:0.80~0.87)和9.90 (95%CI:4.75~20.63).结论 目前研究证据表明,miR-21对肺癌具有较好诊断价值,可作为肺癌诊断的潜在指标.  相似文献   
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There is strong evidence to suggest that inflammatory responses link obesity and diseases, and the understanding of obesity-induced inflammatory mechanisms is central to the pathogenesis of diseases such asnonalcoholic fatty liver disease(NAFLD) and atherosclerosis that are modified by obesity. Based on this, anti-inflammatory treatments become a potential therapies for obesity-related diseases like NAFLD.A critical role of toll-like receptor (TLR) and its downstream molecules such as tumor necrosis factor receptor-associated factor 6(TRAF6) has been documented in inflammatory response induced by fatty acid. TLR pathway regulation provides a new insight to controlling the inflammatory response induced by fatty acid. Taken together, our study was aimed to understand the mechanism of fatty acid-mediated inflammation and look for an effective target which can prevent the inflammatory response induced by obesity. In this study, we used the saturated fatty acid palmitic acid (PA) to activate TLR4 signal pathway in human monocyte cells THP-1 that established an intracellular inflammatory model. Followed with activated TLR4, downstream molecular TRAF6 was upregulated and ultimately induced proinflammatory cytokine production. Based on this model, we also found that PA downregulated miR-194 expression with TLR4 activation. Moreover, our results showed that key signal molecular TRAF6 is a target of miR-194, overexpression of miR-194 directly decreased TRAF6 expression and attenuated the release of proinflammatory cytokine TNF-α in PA-activated monocyte THP-1. We conclude that miR-194 negatively regulates the TLR4 signal pathway which is activated by PA through directly negative TRAF6 expression.  相似文献   
15.
目的]探究急性缺血性脑卒中(AIS)患者血清微小RNA-590(miR-590)水平变化及与预后的关系。[方法]选取2019年2月—2020年10月接受静脉溶栓和动脉取栓治疗的176例AIS患者作为研究对象,根据治疗后90天的改良Rankin量表(mRS)评分将其分为预后良好组(n=123;mRS评分0~2分)、预后不良组(n=53;mRS评分3~6分)。用实时荧光定量PCR法检测AIS患者血清miR-590水平;用受试者工作特征(ROC)曲线评价miR-590预判AIS预后的价值;用Logistic回归分析AIS预后的风险因素。[结果]预后不良组的年龄、男性占比、糖尿病史占比、空腹血糖(FPG)、总胆固醇(TC)、美国国立卫生研究院卒中量表(NIHSS)评分和入院至溶栓时间(DNT)均高于预后良好组(P<0.05)。按1∶1进行倾向性评分匹配后,治疗前预后不良组的miR-590相对水平低于预后良好组,预后不良组和预后良好组的治疗后miR-590相对水平均高于治疗前,治疗后预后不良组的miR-590相对水平升高程度高于预后良好组,差异均有统计学意义(P<0.05)。治疗前miR-590预判AIS预后的ROC曲线下面积为0.793,高于miR-590差值(治疗前和治疗后血清miR-590相对水平的差值)(P<0.001)。Logistic回归分析结果显示FPG、TC、NIHSS评分和DNT是AIS预后的独立危险因素(P<0.05),治疗前血清miR-590水平是AIS预后的独立保护因素(P<0.001)。[结论]AIS患者静脉溶栓和动脉取栓治疗前血清miR-590水平低与AIS预后不良有关。  相似文献   
16.
目的探讨microRNA-144 (miR-144)对非小细胞肺癌(Non-small-cell lung cancer,NSCLC)细胞增殖以及预后的影响。方法通过癌症基因组图谱(The cancer genome atlas,TCGA)检测NSCLC患者组织中miR-144以及泛素样PHD和环指结构域包含1(Ubiquitin like PHD and ring finger domain 1,UHRF1)的表达预后以及两者表达的相关性。采用CCK-8、AO/EB以及γH2A检测不同表达miR-144对NSCLC细胞活性、细胞凋亡、增殖以及DNA损伤的影响,Western blot检测PCNA、Bax、Bcl-2及UHRF1的表达。荧光素酶报告证明miR-144以及UHRF1的靶向关系。结果在NSCLC患者组织中,miR-144表达水平较低,低表达miR-144 NSCLC患者生存时间明显低于高表达miR-144者。UHRF1在NSCLC患者组织中明显升高,且在不同年龄、性别、TNM分期和种族有显著差异。低表达UHRF1非小细胞肺癌患者生存率明显高于高表达UHRF1的NSCLC患者。过表达miR-144能够明显降低A549细胞活性,诱导A549细胞凋亡,增加γH2ax表达;抑制PCNA以及Bax蛋白表达,上调Bcl-2表达。荧光素酶报告证明UHRF1是miR-144的靶基因。同时,低表达miR-144能够使UHRF1表达增加,过表达miR-144能够抑制UHRF1的表达。结论过表达miR-144通过靶向UHRF1诱导A549细胞凋亡以及DNA损伤,参与NSCLC的病理生理过程,进而影响预后。  相似文献   
17.
Yin and Yang are two complementary forces that together describe the nature of real-world elements. Yin is the dark side; Yang is the light side. We describe microRNAs having both Yin and Yang characteristics because they can contribute to normal function (Yang) but also to autoimmunity, myeloproliferation, and cancer (Yin). We have been working on a number of microRNAs that have these dual characteristics and here we focus on two, miR-125b and miR-146a. We have concentrated on these two RNAs because we have very extensive knowledge of them, much of it from our laboratory, and also because they provide a strong contrast: the effects of overexpression of miR-125b are rapid, suggesting that it acts directly, whereas the effects of miR-146a are slow to develop, suggesting that they arise from chronic alterations in cellular behavior.  相似文献   
18.
Innate immunity plays a prominent role in the host defense against pathogens and must be precisely regulated. As vital orchestrators in cholesterol homeostasis, microRNA-33/33* have been widely investigated in cellular metabolism. However, their role in antiviral innate immunity is largely unknown. Here, we report that VSV stimulation decreased the expression of miR-33/33* through an IFNAR-dependent manner in macrophages. Overexpression of miR-33/33* resulted in impaired RIG-I signaling, enhancing viral load and lethality whereas attenuating type I interferon production both in vitro and in vivo. In addition, miR-33/33* specifically prevented the mitochondrial adaptor mitochondrial antiviral-signaling protein (MAVS) from forming activated aggregates by targeting adenosine monophosphate activated protein kinase (AMPK), subsequently impeding the mitophagy-mediated elimination of damaged mitochondria and disturbing mitochondrial homeostasis which is indispensable for efficient MAVS activation. Our findings establish miR-33/33* as negative modulators of the RNA virus-triggered innate immune response and identify a previously unknown regulatory mechanism linking mitochondrial homeostasis with antiviral signaling pathways.  相似文献   
19.
MicroRNAs (miRNAs) can function as tumor suppressors and might provide an efficient strategy for annihilating cancer. Specific miRNAs can be reintroduced into tumor cells to complement the loss of tumor suppression activities. The “miRNA replacement therapy” is based on the concept that the reintroduction of miRNAs depleted in cancer cells reactivates cellular pathways that lead to therapeutic responses. Here, we report the development of miRNA delivery formulation using synthesized miR-520e. This formulation proved to be effective either locally or systematically. MiR-520e accumulation becomes evident in tumor cells and then exerts anti-proliferative function. Meanwhile, intravenous delivery of formulated miR-520e does not induce any deregulation in cytokine levels and liver enzymes. Taken together, our results shed new lights on the concept that systematic delivery of synthetic mimics for tumor suppressor miR-520e and provide potential implications for miRNA therapy in clinic.  相似文献   
20.
目的探讨人白血病细胞中微小RNA(microRNA)-1271对CYLD蛋白表达的调控作用。方法 qRT-PCR检测microRNA-1271在不同的人白血病细胞系、临床初诊未治的几种类型原代白血病细胞、正常人外周血单个核细胞中的表达差异,利用 Targetscan 信息学预测软件预测 microRNA-1271靶向CYLD基因,构建携带靶基因野生型及突变型3’非翻译区(3’UTR)(缺失了整段预测的microRNA-1271结合序列)的双荧光素酶报告基因质粒,采用脂质体 Lipo-fectamine 3000包裹双荧光素酶重组质粒及 microRNA-1271模拟物(mimic)或阴性对照,共转染HEK293A细胞,应用双荧光素酶报告基因检测试剂盒测定荧光素酶活性。 FAM标记的microRNA-1271抑制物和阴性对照分别核转染至人白血病细胞系K562细胞,Western blot法检测CYLD蛋白水平的表达变化。结果 microRNA-1271在不同人白血病细胞系以及临床初诊未治的原代白血病细胞中的表达均明显高于正常人外周血单个核细胞,双荧光素酶报告基因实验验证CYLD是 microRNA-1271的潜在靶基因;K562细胞中转染microRNA-1271抑制物下调 microRNA-1271后, Western blot法检测结果显示CYLD蛋白水平明显上调。结论人白血病细胞中microRNA-1271的表达上调,下调microRNA-1271后可以促进靶基因CYLD蛋白的表达, microRNA-1271有可能成为白血病治疗的新靶点。  相似文献   
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