Role of miRNA-146?in proliferation and differentiation of mouse neural stem cells

Neural stem cells (NSCs) have been defined as neural cells with the potential to self-renew and eventually generate all cell types of the nervous system. NSCs serve as an ideal cell type for nervous system repair. In the present study, miR-146 overexpression and predicted target (notch 1) were used to study proliferation and differentiation of mouse NSCs. shRNA were used to demonstrate the function of Notch 1 in proliferation of mouse NSCs and luciferase reporter assay was used to assess and confirm the binding sequence of 3′-UTR between Notch 1 and miR-146. Results showed that miR-146 overexpression and knockdown of notch 1 inhibited proliferation of mouse NSCs under serum-free cultural conditions and promoted spontaneous differentiation of mouse NSCs under contained serum cultural conditions respectively. Mouse NSCs spontaneously underwent differentiation into neurogenic cells with contained serum medium. However, when miR-146 was overexpressed, differentiation efficiency of glial cells from NSCs was increased, suggesting that Notch1 promoted NSC proliferation and repressed spontaneous differentiation of NSC in serum-free medium. In conclusion, our results demonstrate that miR-146 promoted spontaneous differentiation of NSCs, and this mechanism was influenced by miR-146, as well as its target (notch 1) and downstream gene.     

血清miRNA-93、miRNA-223联合miRNA-324-3p可作为诊断PCOS的生物标记物

本研究拟基于最近的miRNA报道,结合前期关于肌肉生长抑素(myostatin, MSTN)的相关研究,探究多囊卵巢综合症(ploycystic ovary syndrome, PCOS)患者血清miRNA和生长抑素的表达及其相关临床病理特征。本研究选取160例在湘南学院附属医院妇科就诊的女性为研究对象,通过PCR、ELISA等方法比较PCOS患者血清miRNA和生长抑素的表达情况,并且分析其相关临床病理特征。结果显示,通过PCR的方法发现mi RNA-93、mi RNA-223在PCOS患者的血清中显著升高,而mi RNA-4522、mi RNA-6767-5p和mi RNA-324-3p则表达下降。本研究建立了3个miRNA的预测模型,并证实预测模型在筛选组和验证组中有很好的敏感性和特异性,可以有效区分PCOS患者和正常人群,但研究结果也发现,miRNA模型结合MSTN没有更好的诊断价值。     

Co-delivery of miRNA-15a and miRNA-16–1 using cationic PEGylated niosomes downregulates Bcl-2 and induces apoptosis in prostate cancer cells

Biotechnology Letters - Tumor suppressor miRNAs, miR-15a and miR-16–1, with high-specificity and oncogenic targeting of Bcl-2, can target tumor tissues. Disadvantages of the clinical...     

miRNA-1和miRNA-133过表达对L6细胞增殖与分化的影响

目的观察大鼠微小RNA-1（miR-1）、微小RNA-133（miR-133）过表达对L6成肌细胞增殖分化的影响。方法分别构建miR-1、miR-133的重组慢病毒载体,并进行测序鉴定,稳定转染L6细胞后,用RT-PCR Taqman探针的方法检测miR-1、miR-133的表达水平;细胞计数实验（CCK-8试剂盒）评价miR-1、miR-133过表达后对L6细胞增殖的影响。诱导稳定转染后L6成肌细胞进行分化,观察miR-1、miR-133过表达后对L6细胞分化的影响。以Western blot法检测miR-1、miR-133过表达后,α肌动蛋白（skeletalα-actin）表达水平的变化。采用Kruskal-Wallis H检验、重复测量和单因素方差分析进行比较。结果miR-1慢病毒载体经酶切和测序鉴定序列准确,转染48 h后L6细胞miR-1组（4.292±0.50）比control组（0.231±0.86）、miR-133组（0.205±0.48）比control组（3.564±0.45）表达均显著上调（P〈0.001）;细胞计数和细胞分化实验显示,培养120 h后,过表达miR-1的L6细胞α肌动蛋白（skeletalα-actin）比对照组（0.415±0.02）表达显著升（0.676±0.02,F=222.144,P〈0.001）,分化明显加快,但增殖无明显变化;而过表达miR-133的L6细胞增殖明显加快,α肌动蛋白表达呈下降趋势（0.363±0.02,F=2385.643,P〈0.001）,分化受到抑制。结论 miR-1、miR-133慢病毒表达载体稳定转染L6成肌细胞后高效表达miR-1和miR-133,miR-1可促进L6细胞分化,miR-133能促进L6细胞增殖但抑制其分化。     

人miRNA-483与疾病最新研究进展

MicroRNA(miRNA)是一类内源基因编码的长度为22个左右核苷酸的单链非编码RNA,广泛存在于真核细胞中,通过作用于特异靶分子mRNA的3'-UTR,导致该m RNA直接降解或抑制其翻译过程,发挥转录后水平调控基因表达作用。人miRNA-483来源于类胰岛素生长因子2(Insulin-like growth factor 2,IGF2)的第2内含子,经加工为miR-483-3p和miR-483-5p两个成熟体形式。近几年的研究发现人miRNA-483是一种非常重要的miRNA分子,目前已通过实验验证了10余个靶基因,通过调控靶基因参与了肿瘤发生和心血管等疾病发病过程。本文对人miRNA-483参与多种肿瘤、心血管和青光眼等多种疾病过程最新的研究进展作一综述。     

miRNA-124靶标功能的生物信息学挖掘

以miRNA-124为例,将miRNA的靶标预测信息与芯片数据分析中下调的基因信息整合起来,从而筛选出miRNA-124的候选靶标,然后对这些靶标的功能进行了深入分析.研究结果表明miRNA-124的靶标可分为两类:直接靶标和间接靶标,间接靶标是通过直接靶标的调控起作用的.miRNA-124靶标的功能主要是蛋白结合作用.miRNA-124靶标的筛选和功能挖掘,为科学工作者选择和验证其它miRNAs靶标的功能打下了坚实的基础,同时此方法可以推广到其它miRNAs的功能研究中.     

Regulation of miRNA-21 by reactive oxygen species-activated ERK/NF-κB in arsenite-induced cell transformation

After acute exposure of cells to arsenic, reactive oxygen species mediate changes in cell behavior, including activation of proliferative signaling. For chronic exposure to arsenic, however, the function of reactive oxygen species in cell transformation remains poorly understood. Although microRNA-21 (miR-21) has been implicated in various aspects of carcinogenesis, its functions and molecular mechanisms in carcinogen-induced tumorigenesis are unclear. The purpose of this study was to determine if miR-21 is involved in arsenite-induced malignant transformation and to characterize the associated signaling pathways. During arsenite-induced transformation of human embryo lung fibroblast (HELF) cells, miR-21 was upregulated, and the extracellular signal-regulated kinase (ERK)/nuclear factor-κB (NF-κB) signal pathway was activated. Moreover, superoxide radical dismutase (a scavenger of superoxide) and catalase (a scavenger of hydroperoxides) blocked the arsenite-induced effects in HELF cells and mouse embryonic fibroblasts. Blockage of ERK by the inhibitor U0126 or inhibition of NF-κB p65 by siRNA or Bay 11-7082 prevented the increases in miR-21 and the decreases in Spry1, Pten, and Pdcd4, the target proteins of miR-21, induced by arsenite. As determined by a ChIP-qPCR assay, NF-κB p65 regulated miR-21 expression by binding directly to the promoter of miR-21. Further, anti-miR-21 downregulated miR-21 expression and prevented the arsenite-induced activation of ERK via the increase in Spry1, indicating that miR-21 has a feedback effect in regulating ERK activation. Overexpression of miR-21 with an miR-21 mimic and feedback activation of ERK and NF-κB via the decrease in Spry1 promoted the malignancy of HELF cells exposed to arsenite, but knockdown of miR-21 with anti-miR-21 and feedback blockage of ERK and NF-κB activation through an increase in Spry1 decreased anchorage-independent growth of arsenite-transformed cells. Thus, the transformation of HELF cells induced by chronic exposure to arsenite is mediated by increased miR-21 expression, which, in turn, is mediated by reactive oxygen species activation of the ERK/NF-κB pathway.     

miRNA-125家族与肿瘤关系的研究进展

miRNA-125家族是由在进化上高度保守的miRNA-125a-3p、miRNA-125a-5p、miRNA125b-1、miRNA-125b-2组成,其表达紊乱与肿瘤的发生与发展密切相关。miRNA-125家族的下游靶点包括转录因子如STAT3、细胞因子(如IL-6,TGF-β)、相关蛋白(如抑癌蛋白p53、促凋亡蛋白Bak1、RNA结合蛋白Hu R)等。miR-125家族参与调控这些靶点进而影响肿瘤的发生发展。现主要总结了miRNA-125家族及其靶基因在抑制与促进肿瘤发生、发展方面的双重作用,并从增殖、凋亡、侵袭与转移和免疫反应等4个方面详细阐述了其作用机制。     

miRNA-105在胃癌组织中的表达情况

目的:分析胃癌组织与癌旁正常胃黏膜组织中miRNA的差异表达情况。方法:收集胃癌组织和其相应癌旁正常胃黏膜组织共33对,经抽提、纯化RNA后,反转录合成荧光分子Hy3的cDNA探针,将其与miRCURYTMLNA Array(v.16.0)(Exiqon公司)芯片进行杂交,应用Axon GenePix 4000B芯片扫描仪来扫描miRNA芯片的荧光强度,GenePix Pro 6.0软件(Axon)把图像转化为数字信号,以差异大于2倍的为标准来确定胃癌黏膜组织中差异表达的miRNA。再用实时荧光定量PCR方法验证芯片结果中表达异常增高的miR-105在33例胃癌组织中的表达情况。结果:miRNA表达谱芯片结果显示:胃癌组织共中有51种miRNA表达异常,其中miR-105、miR-548n、miR-214*、miR-4309等31种miRNA表达上调,miR-31、miR-1275、miR-26b*、miR-744等20种miRNA表达下调;实时荧光定量PCR证实与癌旁正常胃黏膜组织相比,胃癌组织中miR-105表达显著上调(P0.01)。结论:miR-105在胃癌组织的表达明显高于正常胃黏膜组织,可能与胃癌的发生、发展相关。我们的研究为胃癌的发病机制和诊断治疗提供了一个新的研究方向。     

Age-related decrease of miRNA-92a levels in human CD8+ T-cells correlates with a reduction of naïve T lymphocytes

MicroRNA (miR)-17-92a expression plays a crucial role in lymphocyte ontogeny. We therefore set out to determine miR-92a expression levels in peripheral blood lymphocytes from healthy subjects to ascertain any association between these levels and ageing. We found a positive correlation between the miR-92a expression level and the percentages of RO-CD8⁺CD27⁺ (P = 0.0046) and CD3⁺CD8⁺CD62L⁺ (P = 0.0011). This suggests that the majority of miR-92a of CD8⁺ T cells is derived from naïve cells, and the miR-92a expression level in CD8⁺ T cells declines progressively with age. These results indicate that the age-related attrition of naïve T cells is linked to a reduction of miR-92a in human T -lymphocytes. Therefore, we should careful attention when evaluating human miRNA levels in T lymphocytes to use normal control values.     

血浆miRNA-1、miRNA-21对冠心病合并糖尿病患者PCI术后支架内再狭窄的影响

目的：观察血浆miRNA-1、miRNA-21在冠心病（CHD）与无冠脉病变患者中含量的差异,探讨其在CHD合并糖尿病（DM）患者的经皮冠状动脉介入治疗（PCI）后发生支架内再狭窄（ISR）与非支架内再狭窄（NISR）患者的含量差异及其对ISR的预测价值。方法：入选CHD支架置入术后患者（CHD组,n=187）、无冠脉病变患者（对照组,n=195）。根据指南,将对照组分为正常对照组（n=150）、单纯DM组（n=45）;将CHD组分为单纯CHD组（n=119）、CHD合并DM组（n=68）,又将CHD组分为ISR组（n=48）及NISR组（n=139）;再将ISR组分为单纯ISR组（n=26）和ISR合并DM组（n=22）。收集各组患者血浆,提取总miRNA,检测miRNA-1、miRNA-21含量并分析各组的含量差异。结果：与对照组比较,CHD组miRNA-1、miRNA-21含量均升高（P<0.05）;与NISR组比较,ISR组miRNA-1、miRNA-21含量均升高（P<0.05）。与单纯CHD组比较,CHD合并DM组ISR发生率明显升高;而且与单纯ISR组比较,ISR合并DM组miRNA-21含量升高（P<0.05）,而单纯ISR组与ISR合并DM组miRNA-1含量无明显差异（P<0.05）。Logistics分析表明,与CHD患者相关危险因素DM、miRNA-1、miRNA-21的OR值分别为2.132,3.066,1.924（P<0.05,P<0.01）;ISR患者相关危险因素DM、miRNA-21的OR值分别为3.091,5.654（P<0.05,P<0.01）;CHD合并DM患者PCI术后发生ISR相关危险因素miRNA-21的OR值为9.148（P<0.01）。ROC曲线评价表明,miRNA-1,miRNA-21与CHD患者发生ISR的AUC分别为0.854,0.857;miRNA 21与CHD合并DM患者发生ISR的AUC为0.783。结论：血浆miRNA-1、miRNA-21对诊断CHD患者支架置入术后ISR发生有重要临床意义,miRNA-21对诊断CHD合并DM患者支架置入术后ISR发生尤其有重要临床意义。     

miRNA-27 a在心血管疾病中的作用机制

心血管疾病作为常见的临床慢性疾病是导致死亡的主要原因.微小核苷酸(microRNAs,miRNAs)作为一类长度约为19～25 nt的内源性非编码RNA,在心血管疾病的发生和发展中起着重要作用.miRNA-27 a通过调控免疫、炎症反应以及多种病理生理过程,从而参与心血管疾病的发病过程.本文对miRNA-27 a在心血...     

miRNA-125b在膀胱癌中的表达和意义

目的:探讨膀胱癌组织中miR-125b的表达在膀胱癌发生发展中的作用及其临床意义。方法:采用应用茎环RT-PCR的方法检测66例膀胱尿路上皮癌组织标本的miR-125b的表达,另有16例正常膀胱黏膜组织作对照,并结合临床病理资料进行统计学分析。结果:miR-125b在膀胱癌组织中的表达显著高于非肿瘤的正常膀胱黏膜组织(p0.05),miR-125b的水平还与表达水平与膀胱癌的组织学分级、肿瘤转移、术后复发均明显相关性(P0.05)。结论:miR-125b在膀胱癌组织中表达量升高,且与组织学分级、肿瘤转移、术后复发相关,可能作为膀胱癌诊断和预后指标。     

miRNA-125在肝癌中表达变化的研究

目的:探讨微小RNA(miRNA)-125在正常人和肝癌患者血清,以及肝癌患者正常肝脏组织和肝癌组织中的表达.方法:应用荧光实时定量PCR方法检测miRNA-125,包括miRNA-125a、miRNA-125b在正常人和肝癌患者血清中的含量.同时收集并检测肝细胞癌患者术中取得的正常肝脏组织和癌症组织miRNA-125含量.结果:1)与正常人血清相比,miRNA-125在癌症患者血清中的含量没有明显变化.2)与正常肝脏组织相比,肝癌组织中miRNA-125含量明显下调,有统计学差异(P＜0.001).结论:MiRNA-125,包括miRNA-125a和miRNA-125b在肝癌组织中表达显著减少,但是在肝癌患者血清并没有明显变化.     

miRNA-181在肝癌中表达变化的研究

目的:观察微小RNA(miRNA)-181在正常人肝细胞L02、肝癌细胞株SMMC7221和Hep3B中的表达,以及在正常肝脏组织和肝癌组织中的表达,探讨其与肝癌发生发展的关系.方法:应用荧光实时定量PCR方法检测miRNA-181,包括miRNA-181a、miRNA-181b、miRNA-181c、miRNA-181d,在正常肝细胞和肝癌细胞的含量.同时收集并检测肝细胞癌患者术中取得的正常肝脏组织和癌症组织的含量.结果:MiRNA-181在肝癌细胞株中的表达明显高于正常人肝细胞(P＜0.05或P＜0.001).MiRNA-181在肝癌组织中表达明显高于正常肝脏组织(P＜0.05).结论:MiRNA-181在不同肝癌细胞株中表达不同,但都高于正常肝细胞,并且miRNA-181在肝癌组织中的表达高于正常肝脏组织.这说明miRNA-181与肝癌的发生发展有相关性,可能成为肝癌诊断和预后的一个指标.     

miRNA-492在肝癌中表达变化的研究

目的:通过观察miRNA-492在肝细胞株L02、肝胚细胞瘤HepT1细胞株和肝癌SMMC-7721细胞株中的表达差异,以及在正常肝脏组织、肝母细胞瘤组织和原发性肝癌组织中的含量差异,探讨其与不同类型肝脏肿瘤发生发展的关系.方法:应用Real time-PCR方法检测miRNA-492在正常L02肝细胞株和肝癌HepT1、SMMC-7721细胞株的含量.同时采集和检测原发性肝癌患者术中取得的正常肝脏组织和癌症组织,以及肝母细胞瘤患者瘤组织的含量.结果:1)与正常人L02肝细胞相比,miRNA-492在肝癌HepT1细胞株中的表达显著升高(P＜0.001),但在SMMC-7721细胞株中略升高,无统计学差异.2)与正常肝脏组织相比,miRNA-492在肝母细胞瘤的瘤组织中含量显著升高(P＜0.01),但原发性肝癌的癌组织略升高,无统计学差异.结论:miRNA-492在不同肝癌细胞株中表达不同,在肝胚细胞瘤中表达升高,且在肝母细胞瘤瘤组织中的表达高于正常肝脏组织.但原发性肝癌癌组织中变化不明显,这说明miRNA-492与某些类型肝癌,特别是肝母细胞瘤的发生发展有关.     

miRNA-200 家族在卵巢癌中作用的研究进展

MicroRNA(miRNA)是一类非编码小分子RNA,参与基因转录后水平调控,与肿瘤的形成、侵袭及转移、治疗及预后过程密切相关。研究发现,miRNA-200家族包括miR-141、miR-200a、miR-200b、miR-200c和miR-429在卵巢癌中的表达改变明显,且参与卵巢癌的发生、侵袭转移、卵巢癌细胞对紫杉醇的敏感性及复发过程,可能是用于卵巢癌的早期诊断、治疗、预后预测的指标。本文主要对miRNA-200家族在卵巢癌中的研究进展进行综述。     

miRNA-132增强人类免疫缺陷病毒1型复制

小分子RNA（miRNA）在CD4＋T细胞活化期间上调可能有助于人类免疫缺陷病毒1型（HIV-1）在静息期扰动后复制效率的提高。该研究发现,miRNA-132（miR-132）在CD4＋T细胞活化后高度上调,且能增强病毒在JurkatCD4＋T细胞系中的复制。