垂体生长激素腺瘤患者血清miR-212与SIRT1表达及与预后相关性

【摘要】 目的 探讨微小RNA-212（miR-212）、沉默信息调节因子1(SIRT1)在垂体生长激素（GH）腺瘤患者血清中的表达水平及与预后的关系。方法 纳入2016年1月~2019年8月空军军医大学第一附属西京医院收诊的58例垂体GH腺瘤患者设为观察组,选取同期于本院体检的62例健康者设为健康组;采用实时荧光定量PCR（qRT-PCR）法检测所有研究对象血清miR 212、SIRT1、缺氧诱导因子-1α（HIF-1α）、血管内皮生长因子（VEGF）表达水平;比较不同预后垂体GH腺瘤患者血清miR-212、SIRT1、HIF-1α、VEGF水平;采用Pearson法分析垂体GH腺瘤患者血清miR-212、SIRT1表达水平与HIF-1α、VEGF相关性及miR-212表达水平与SIRT1的关系;采用受试者特征工作曲线（ROC）评价血清miR-212、SIRT1对垂体GH腺瘤患者预后的诊断价值。结果 观察组患者血清miR-212表达水平明显低于健康组（t=7.434,P＜0.05）,血清SIRT1、HIF-1α、VEGF表达水平明显高于健康组（P＜0.05）;未缓解组垂体GH腺瘤患者血清miR-212表达水平明显低于缓解组（P＜0.05）,血清SIRT1、HIF-1α、VEGF表达水平明显高于缓解组（t=2.536、3.242、2.638,P＜0.05）;垂体GH腺瘤患者血清miR-212表达水平与HIF-1α、VEGF、SIRT1水平均呈负相关（P＜0.05）,血清SIRT1表达水平与HIF-1α、VEGF呈正相关（P＜0.05）;血清miR-212、SIRT1水平对垂体GH腺瘤患者不良预后评估的曲线下面积（AUC）为0.873、0.862,对应截断值分别为0.52、1.94,此时对应灵敏度分别为81.3%、75.0%,特异度分别为88.1%、85.7%;两者联合诊断垂体GH腺瘤的AUC为0.938,其灵敏度、特异度分别为93.8%、81.0%。结论 垂体GH腺瘤血清miR-212表达下调,SIRT1表达上调,两者可能与HIF-1α、VEGF相互作用,进而协同垂体GH腺瘤发生与发展,miR-212、SIRT1有望成为评估垂体GH腺瘤预后的参考指标,两者联合检测可有效提高垂体GH腺瘤预后价值。     

微小RNA let-7c慢病毒载体的构建及过表达研究

目的 构建微小RNA let-7c重组慢病毒载体,验证转染该载体系统后对肝癌细胞增殖的影响 方法 构建表达含494bp let-7c基因的重组慢病毒载体,检测let-7c及对照组病毒滴度分别为5.01×10E8 TU/m1、5.15×10E8TU/ml;转染HepG2细胞,以荧光定量聚合酶链反应(PCR)对let-7e表达水平进行检测;细胞计数试剂盒(CCK-8)试验评价let-7c过表达后对HepG2细胞增殖的影响.结果 构建的let-7c慢病毒载体经质粒酶切和测序鉴定正确;转染HepG2细胞72 h后,let-7c表达上调312倍;CCK-8法检测显示HepG2细胞增殖受到明显抑制(P＜0.01).结论 成功构建Iet-7c重组慢病毒载体并感染HepG2细胞后高效表达成熟let-7c,抑制了HepG2肝癌细胞的增殖.     

Predisposition to treatment response in major depressive episode: A peripheral blood gene coexpression network analysis

Antidepressant efficacy is insufficient, unpredictable and poorly understood in major depressive episode (MDE). Gene expression studies allow for the identification of significantly dysregulated genes but can limit the exploration of biological pathways. In the present study, we proposed a gene coexpression analysis to investigate biological pathways associated with treatment response predisposition and their regulation by microRNAs (miRNAs) in peripheral blood samples of MDE and healthy control subjects. We used a discovery cohort that included 34 MDE patients that were given 12-week treatment with citalopram and 33 healthy controls. Two replication cohorts with similar design were also analyzed. Expression-based gene network was built to define clusters of highly correlated sets of genes, called modules. Association between each module’s first principal component of the expression data and clinical improvement was tested in the three cohorts. We conducted gene ontology analysis and miRNA prediction based on the module gene list. Nine of the 59 modules from the gene coexpression network were associated with clinical improvement. The association was partially replicated in other cohorts. Gene ontology analysis demonstrated that 4 modules were associated with cytokine production, acute inflammatory response or IL-8 functions. Finally, we found 414 miRNAs that may regulate one or several modules associated with clinical improvement. By contrast, only 12 miRNAs were predicted to specifically regulate modules unrelated to clinical improvement. Our gene coexpression analysis underlines the importance of inflammation-related pathways and the involvement of a large miRNA program as biological processes predisposing associated with antidepressant response.     

β－分泌酶与阿尔茨海默病

阿尔茨海默病（A D ）是最常见的一种痴呆症,主要临床特点为进行性认知功能下降,最终导致身体机能的下降甚至死亡,65岁以上的老年人群多发［1］。对于年轻家族性AD患者而言,AD的发生与多基因因素相关,而对于年老的散发性AD患者,其原因是多重性的,包括基因、环境和后天造成的基因改变等因素。尽管AD的病因不明,但患者脑内β－淀粉样蛋白（Aβ）的增多可能是导致此病的首要原因。Aβ主要是由β－淀粉样前体（APP ）在β－分泌酶（BACE1）的作用下使其在β位点发生裂解而产生,这一过程在AD的病理性神经纤维缠结和淀粉样斑块形成中发挥着重要作用［2］。AD患者中BACE1的表达和活性均有显著升高［3］,已成为诊断AD的一个重要生物指标［4］。而关于BACE1的了解目前还存在很多局限,现通过以下几个方面来讨论近年BACE1在AD中的有关研究进展。     

Helicobacter pylori-induced inflammation and epigenetic changes during gastric carcinogenesis

The sequence of events associated with the development of gastric cancer has been described as “the gastric precancerous cascade”. This cascade is a dynamic process that includes lesions, such as atrophic gastritis, intestinal metaplasia and dysplasia. According to this model, Helicobacter pylori (H. pylori) infection targets the normal gastric mucosa causing non-atrophic gastritis, an initiating lesion that can be cured by clearing H. pylori with antibiotics or that may then linger in the case of chronic infection and progress to atrophic gastritis. The presence of virulence factors in the infecting H. pylori drives the carcinogenesis process. Independent epidemiological and animal studies have confirmed the sequential progression of these precancerous lesions. Particularly long-term follow-up studies estimated a risk of 0.1% for atrophic gastritis/intestinal metaplasia and 6% in case of dysplasia for the long-term development of gastric cancer. With this in mind, a better understanding of the genetic and epigenetic changes associated with progression of the cascade is critical in determining the risk of gastric cancer associated with H. pylori infection. In this review, we will summarize some of the most relevant mechanisms and focus predominantly but not exclusively on the discussion of gene promoter methylation and miRNAs in this context.     

Kinetics of plasma microRNA-499 expression in acute myocardial infarction

Background

MicroRNA (miRNA) is reported to be present in human plasma and has been increasingly suggested as a biomarker for diseases. Our study aimed to investigate the kinetics of cardiac-specific microR-499 (miR-499) in acute myocardial infarction (AMI).

Methods

Circulating concentrations of cardiac enriched miR-499 were measured by quantitative PCR in 73 patients with acute coronary syndrome (ACS), including 53 with AMI and 20 with unstable angina (UA). Thirty healthy subjects were used as controls. Plasma samples in AMI group were obtained immediately after admission and at 12 h, 24 h, 3 d and 7 d after onset of symptoms. Plasma samples in UA and healthy control groups were collected immediately after admission. The severity and extent of coronary stenotic lesions were evaluated on the basis of coronary angiography using Gensini score.

Results

miR-499 expression levels were significantly higher in the 53 AMI patients than in the 20 UA patients and 30 healthy controls immediately after admission (P<0.01). A measurable increase in miR-499 levels was observed in AMI patients within 24 h of the last onset of chest pain and the levels returned to the baseline after 7 d. Plasma miR-499 levels in the patients with AMI were positively-correlated with cTnI (r=0.384, P<0.01) and CK-MB (r=0.402, P<0.01). In addition, miR-499 levels in AMI patients with two- and three-vessel coronary artery disease (CAD) were significantly higher than those in patients with single-vessel CAD (P<0.05). Gensini scores were used to evaluate the severity of coronary stenosis. miR-499 were positively correlated with Gensini scores (r=0.52, P<0.01). miR-499 levels at admission were significantly higher than that those 24 h after percutaneous coronary intervention (PCI) in AMI patients (P<0.01) and were negatively correlated with LVEF (r=0.36, P=0.008).

Conclusions

Cardiac-specific miRNA-499 levels were found to be linearly proportional to myocardial damage. MiRNA-499 might prove to be a new biomarker for AMI and a predictor of the risk of myocardial ischemia.     

MicroRNA Expression Analysis in Patients with Primary Myelofibrosis,Polycythemia vera and Essential Thrombocythemia

MicroRNAs (miRNA) are small non-coding RNA molecules that play critical roles in cell differentiation, proliferation and apoptosis and thus regulate haematopoietic stem cells and committed progenitor cells. We analyzed expressions of miRNAs associated with hematopoietic transformation of myeloid, erythroid and megakaryocytic progenitor cells during haematopoiesis (mir155, mir181a, mir221, mir222, mir223, mir451), in patients with primary myelofibrosis (PMF) (n = 22), polycythemia vera (PV) (n = 33), essential thrombocythemia (ET) (n = 49) and in healthy controls (n = 40) by quantitate/real time polymerase chain reaction. RT-PCR testing was negative for BCR–ABL1 fusion gene in all the patients. Mir155 was expressed in higher levels in all 3 disorders (p < 0.05). Mir221 was higher especially in ET and PMF group (p < 0.05). Mir222 expression was lower in PV patients (p < 0.05) and higher in ET and PMF patients compared to control group. Mir223 expression was higher in ET and PMF group than control group (p > 0.05). Mir451 levels were lower in all three groups compared to control group (p < 0.05). There was no difference in expression levels of mir181a between groups. JAK2V617F positivity, co-morbidities, drugs, and gender did not affect miRNA expressions. This study holds promise for the future application of these molecules for differential diagnosis and as therapeutic targets in Philadelphia chromosome negative myeloproliferative neoplasms.     

miRNA与食管癌

动植物中广泛存在着一大类小的非编码蛋白质的RNA,21-25个核苷酸长度,被命名为microRNA(miRNA). miRNA在物种进化中相当保守,其表达有组织特异性和时序特异性. 其功能为负调控基因表达,进而调节细胞的代谢,增殖,分化和凋亡等基本的生理过程. 因此,miRNA的改变必会导致一些严重的病理过程. 研究已证实miRNA在肿瘤的发生和发展起着癌基因或抑癌基因的作用,miRNA的表达谱可用于某些肿瘤的诊断、分期和判断预后,并且在肿瘤分类方面较mRNA有更大地优越性. 本文着重介绍miRNA的产生,作用机制,与肿瘤的关系,检测方法及其在食管癌的诊断、分期和生物治疗方面的潜在作用.     

The role of microRNA in periodontal tissue: A review of the literature

MicroRNAs (miRNAs) bind at the 3′UTR of their target mRNA to induce gene silencing. Through this mechanism, number of biological pathways implicated in developmental, physiological, and pathological processes, have been frequently found to involve miRNA functions. MiRNA functions in bone metabolism have also been reported, especially in association with receptor activator of nuclear factor kappa B ligand (RANKL)-induced osteoclastogenesis. Expression of RANKL has been related to several inflammatory mediators, and thus some miRNAs may be implicated in the regulatory mechanism of inflammatory-induced RANKL expression as shown in periodontal resident cells such as gingival fibroblasts or periodontal ligament cells. This review aims to review the current miRNA research relating periodontal tissue and its relevance in periodontal inflammation. In miRNA profiling studies of tissues isolated from individuals with periodontal disease, miR-223 has been consistently identified as a potential candidate miRNA to be further investigated in periodontitis-related processes. Although these studies point to an important role of miRNA-mediated epigenetic changes in tissue inflammation and alveolar bone loss, further investigation is still required to determine the function of miRNAs in the complex processes of periodontal tissue homeostasis and pathogenesis. Knowledge gained from future studies will be beneficial in developing alternative therapeutic approaches, especially ones that use miRNA delivery systems to treat periodontal disease.