microRNA介导的基因工程病毒减毒株研究进展

为了安全有效地进行基因治疗,需要把转染的基因限制在特定组织中表达。应用miRNA调节病毒基因表达是一个新方法。在miRNA介导的转基因表达系统中,可以将与miRNA互补的靶序列串联插入病毒基因3’非编码区域,导致在miRNA高表达细胞中抑制病毒的表达。我们总结了miRNA介导的病毒减毒株的应用。     

微小RNA-21转染介导食管鳞癌细胞生物学行为及细胞放射敏感性的变化

目的 探讨微小RNA-21（miRNA-21）表达介导食管鳞癌细胞的生物学特性。方法 转染miRNA-21正义表达载体、miRNA-21空载体及miRNA-21抑制剂,通过Real-time PCR实验,以食管鳞状上皮癌TE-1正常细胞为对照组,检测转染结果。采用细胞计数试剂盒-8(CCK-8）对细胞增殖活性进行检测;采用流式细胞术检测细胞凋亡能力;通过Transwell小室和划痕实验观察TE-1细胞侵袭能力及迁移能力;通过集落形成实验观察TE-1细胞对放疗敏感性变化;采用SPSS 19.0统计学软件对所得数据进行分析。结果 Real-time PCR结果显示,转染miRNA-21抑制剂后,TE-1细胞中miRNA-21的表达水平明显降低（P<0.05）。相比正常细胞生长组,阳性对照组、阴性对照组转染miRNA-21抑制剂后,TE-1细胞增殖能力降低,细胞凋亡加快（P<0.05）。此外,实验抑制组中细胞侵袭和迁移能力下降。集落形成实验分析显示,抑制miRNA-21表达明显提高了TE-1细胞对放射的敏感性。结论 下调miRNA-21可降低食管鳞状上皮癌TE-1细胞的增殖、侵袭、迁移能力及放疗的敏感性,是未来治疗食管癌的潜在靶点。     

外泌体miRNA在心血管疾病中的研究进展

心血管疾病(cardiovascular diseases,CVD)是全球高发性疾病,其中冠心病(coronary heart disease,CHD)是世界范围内的主要死亡原因,在老年人群中死亡率和发病率不断上升[1],与微小RNA(microRNA,miRNA,miR)的调节密切相关[2]。研究报道,miRNA调节大量信号通路,可通过外泌体(exosome)实现细胞间传递,参与细胞间的信息交流[3].     

结肠癌化疗耐药相关miRNA表达谱的初步研究

目的:应用基因芯片技术筛选结肠癌耐药相关微小RNAs (miRNAs),探究miRNAs对化疗耐药的调控机制。方法:采用基因芯片技术分析结肠癌细胞系HCT8及其耐长春新碱细胞系HCT8/v中miRNAs的表达差异,对部分差异表达的miRNAs应用RT-qPCR进行验证,对表达差异显著的miRNAs进行靶基因预测,利用Gene Ontology (GO)和京都基因与基因组百科全书(KEGG)数据库对预测到的靶基因进行生物信息学分析。结果:筛选出342个差异表达miRNAs,其中190个表达上调,152个表达下调。RT-qPCR验证结果示miR-125-5p、miR-181c-5p和miR-153-3的表达情况和芯片检测结果一致;miR-130a-3p和miR-149-3p的表达与芯片检测结果不一致。GO分析结果显示,耐药相关基因主要富集的旁路是RNA聚合酶II调控区序列特异性DNA结合旁路,主要通过正向调节发挥作用,位置主要是在细胞内有界细胞器上。KEGG分析结果显示,耐药相关基因最为富集的是轴突导向通路、胰岛素信号通路及磷脂酶D信号通路。结论:miRNAs与结肠癌化疗耐药密切相关。对这些miRNAs的研究能使我们对结肠癌的化疗耐药机制有更深入的理解,并为逆转化疗耐药提供新的思路。     

miRNAs in lung cancer: A link to aging

Lung cancer is a leading cause of cancer deaths worldwide. Development of lung cancer is associated with exposure to carcinogens such as tobacco smoke and some environmental factors. The incidence of lung cancer increases with age, particularly after age 60. It was estimated that less than 2% of all lung cancer cases occurred in patients younger than 45; therefore, this type of tumor can be considered as an aging-related disease. MicroRNAs (miRNAs) are small non-coding RNA molecules capable of regulating expression of over 50% of protein-coding genes. miRNAs were shown to play an extremely important role in cell functioning, affecting all biological processes, as well as development of various diseases. Expression profiles of miRNAs are known to be altered in cancer, including lung cancer, and also exhibit changes during aging. These RNA molecules are stable in tissue sections and blood and reflect tumor origin, histotype, and stage, which make them candidate diagnostic and prognostic biomarkers. miRNA mimetics or inhibitors can be delivered into a cell, with possible therapeutic implications. Here, we review the results obtained during the last several years that demonstrate the aging-related regulation of miRNAs expression, in association with their role in lung cancer initiation, progression, and resistance to anticancer therapy, as well as the possibility to use miRNAs as predictive biomarkers for treatment response.     

Spontaneous periodontitis is associated with metabolic syndrome in rhesus monkeys

Objective

The present study was designed to investigate (1) whether the non-human primate would be an appropriate animal model for the study of spontaneous periodontitis and its association with metabolic syndrome (MetS), and (2) whether microRNAs (miRNAs) play roles in the co-development of metabolic disorders and periodontitis.

Design

Rhesus monkeys (aged 12–29 years) with or without MetS were analyzed for the prevalence of periodontitis. The potential mechanisms underlying the association between MetS and periodontitis were explored using miRNA profiling of the gingival tissues from the MetS monkey groups with or without periodontitis as well as the age-matched controls.

Results

Among the 57 rhesus monkeys examined, 18 were diagnosed with periodontitis according to the inclusion criteria, with an overall prevalence of 31.6%. Moreover, the prevalence of periodontitis was 8.3% in the control group, 18.2% in the at-risk group, and 44.1% in the MetS group. The C-reactive protein level was doubled in the MetS periodontitis group, compared to the non-periodontitis sub-groups. Most importantly, only 3 miRNAs were confirmed to be differentially expressed between the MetS periodontitis and non-periodontitis subgroups while other miRNAs showed similar expression profiles.

Conclusions

The results indicate that the monkey with MetS is an ideal model for studies of spontaneous periodontitis and its association with MetS. miRNA profiling using this unique model showed that miRNAs play roles in the co-development of MetS and periodontitis.     

miR-21 inhibitor suppresses proliferation and migration of nasopharyngeal carcinoma cells through down-regulation of BCL2 expression

This study is to investigate the expression of miR-21 in nasopharyngeal carcinoma (NPC) cells, and the effect of miR-21 in the biological behavior and expression of B-cell lymphoma 2 (BCL2) in NPC cells. Paired NPC and adjacent non-tumor tissues were obtained from 53 patients who underwent primary surgical resection of NPC tissues. Luciferase reporter assay was performed to test whether BCL2 is a direct target of miR-21. Methylthiazolyl blue tetrazolium assay and colony assay were used to evaluate the effect of miR-21 on NPC cell proliferation. Transwell and wound-healing assays were carried out to test the effect of low expression of miR-21 on cancer cell migration and invasion. QRT-PCR and Western blotting were used to measure the levels of mRNA and protein expression, respectively. Tumor tissues showed a positive correlation between the levels of miR-21 and BCL2 protein expression. Cells transfected with miR-21 inhibitor healed slower compared the control (P < 0.05). In addition, cell migration was notably inhibited by the down-regulation of miR-21 in vitro (P < 0.05). The reduction in miR-21 expression showed a remarkable effect on the biological behavior of NPC cell clone formation (P < 0.05). Low expression of miR-21 by transfection with miRNA expression plasmid led to a decrease in BCL2 expression, which was accompanied by reduced migration and proliferation of the cancer cells. Our results demonstrated that miR-21 inhibitor down-regulated BCL2 expression level, suggesting that BCL2 might be a target gene for the initiation and development of NPC cells.     

抗磷脂抗体和子痫前期的研究进展

抗磷脂抗体是一类能与磷脂或磷脂结合蛋白结合的自身免疫性抗体,与血栓形成、不良孕产史密切相关。抗磷脂抗体中高滴度阳性的患者易有子痫前期等不良妊娠结局。子痫前期发生于妊娠期,可导致全身多脏器的损伤,严重危及母儿生命和健康。子痫前期的发病机制目前还不是很清楚,研究提示抗磷脂抗体可能通过诱导氧化应激,促进血管内炎症等作用参与子痫前期的发病;对于抗磷脂抗体阳性的患者,早期发现和早期干预对获得良好的妊娠结局至关重要。