外泌体miR-221在胃癌中的作用

外泌体是一种存在范围广泛、功能作用多样的膜性小囊泡,与肿瘤的发生发展紧密相关。外泌体miR-221为内源性非编码的RNA分子,在胃癌相关研究中极具价值。本综述主要介绍了外泌体的形成特点、功能作用以及外泌体miR-221与胃癌的相关作用机制和诊疗进程之间的联系,指出外泌体miR-221水平的高表达与胃癌的发生发展关系密切,提示其可作为潜在的生物标志物,为胃癌的早期诊断和治疗提供新的研究思路,以帮助临床解决胃癌这一难题。     

miR-221促进前列腺癌LNCaP细胞系神经内分泌样转化

目的:研究miR-221对于前列腺癌细胞的神经内分泌化改变的影响,探讨miR-221在前列腺癌的雄激素剥夺治疗中发挥的作用.方法:免疫组织化学研究雄激素依赖性前列腺癌与雄激素非依赖性前列腺癌中NSE表达的差异.在前列腺癌细胞LNCaP上,观察基因转染前后miR-221对于LNCaP细胞的形态学改变,以及通过qRT-PCR和Western-blot方法检测细胞中NSEmRNA水平以及NSE蛋白表达的变化.结果:①免疫组化显示AIPC标本的NSE水平明显高于ADPC标本(P<0.05);②形态学观察:转染miR-221的前列腺癌细胞神经内分泌化改变明显加速③转染miR-221的LNCaP细胞中NSE的mRNA以及蛋白水平均较转染anti-mir-221和miR-NC组明显升高.结论:miR-221对于前列腺癌的神经内分泌化进程有明显的促进作用.     

肿瘤干细胞及肝癌肿瘤干细胞

肿瘤干细胞理论认为只有存在于肿瘤中的少量干细胞性质的细胞群体对肿瘤发生和发展起着决定作用,肿瘤是由干细胞突变积累而形成的无限增殖的异常组织,这一理论的提出使人们对肿瘤发生机制的认识上升到了一个新的高度,也引起了研究者的广泛关注;肝癌是我国常见的恶性肿瘤之一,我国肝癌死亡率居世界之首,目前对肝癌的研究是我国恶性肿瘤防治的重点工作,现对当前肿瘤干细胞与肝癌肿瘤干细胞相关方面的最新研究进展作一概述。     

肿瘤干细胞标记物CD133与miR-429在大肠癌组织中的表达及其相关性研究

目的：检测CD133不同亚群大肠癌细胞HT-29的miR-429表达情况,探讨miR-429及CD133的表达与肿瘤的发生发展之间的关系。方法：采用荧光活化细胞分选法（FACS）分选出CD133不同亚群细胞,实时荧光定量PCR分别检测两组细胞miR-429的表达,合成miR-429寡核苷酸和阴性对照miRNA并分别转染CD133＋和CD133＋两个亚群细胞。再将细胞种植于非肥胖糖尿病／严重联合免疫缺陷（NOD／SCID）小鼠体内构建移植瘤模型,不同时间测量肿瘤体积和重量,RT—PCR及蛋白质印迹检测CD133＋和CD133＋两组肿瘤CD133mRNA和蛋白质表达。结果：血清检出CD133＋细胞为67．9％,miR-429的表达量是CD133＋细胞的（1．83±0．91）倍（P〈0．05）,CD133＋比例与miR-429表达呈负相关（r=0．591,P〈0．05）;miR-429＋／CD133＋组的移植瘤体积及重量与对照组比较有统计学差异（P〈0．05）,且miR-429＋/CD133＋组成瘤时间较对照组晚约2周,但miR-429＋/CD133＋组的移植瘤CD133表达量低,与阴性对照组比较无明显差异（P〉0．05）。结论：miR-429可能作为CD133的负性调控因子,具有抑制肿瘤生长的作用,但miR-429与CD133在肿瘤发生、发展过程中的作用机制有待进一步研究阐明。     

miRNAs在肝癌干细胞中的作用

MicroRNAs (miRNAs)是一类参与转录后调控的小分子RNA,它在调控细胞的增殖、分化及肿瘤的形成等多种生理及病理过程中发挥着重要的作用.肝癌干细胞是肝癌组织中具有自我更新能力和分化潜能的一个微群体,它能够启始肝癌的发生,并且与肝癌的抗药性及复发等密切相关.已经有研究表明miRNAs对肝癌干细胞的发生发展起着重要的调控作用,包括致癌和抑癌的作用,因此总结miRNAs在肝癌干细胞中作用,有助于更好理解肝癌干细胞的特性及肝癌肿瘤生物学.近年来,除了传统的分子生物学手段,组学和系统生物学研究策略的运用也为miRNAs在肝癌中的研究提供了新的思路.鉴于此,深入研究miRNAs在肝癌干细胞中的分子机制,将为靶向肝癌干细胞的临床治疗提供新的途径.     

miR-224在原发性肝癌患者血清中的表达及意义

目的：原发性肝癌（primary hepatocellular carcinoma,PHC）作为常见的恶性程度极高的肿瘤,严重威胁着人类的生命。miR-224是近年来发现的一个肿瘤相关miRNA分子,在肿瘤的发生及发展过程中发挥着重要的作用。本研究通过测定原发性肝癌患者血清中miR-224的表达水平,探讨血清miR．224与原发性肝癌预后的关系。方法：采用实时荧光定量RT-PCR（Real-timeRT．PCR）方法。分别检测40例原发性肝癌患者,20例慢性肝炎患者,20例慢性肝硬化患者及20例正常人的血清标本中miR-224的表达水平。分析血清miR-224的表达水平与AFP和MMP-9的相关性。结果：原发性肝癌患者血清miR-224的表达水平明显高于正常人、慢性肝炎和慢性肝硬化患者（P〈0．05）。皮尔森相关分析结果显示原发性肝癌患者血清miR-224的表达与AFP和MMP．9呈正相关。血清miR-224低表达组术后复发／转移率显著低于高表达组,术后生存率则高于高表达组（P〈0．01）。结论：miR-224在原发性肝癌患者的血清中呈高表达,其血清表达水平与原发性肝癌的临床预后密切相关。这提示我们,miR-224可能成为新的原发性肝癌检测标记物和潜在的原发性肝癌预后分子标志物。     

肿瘤干细胞标记物CD_(133)与miR-429在大肠癌组织中的表达及其相关性研究

目的:检测CD133不同亚群大肠癌细胞HT-29的miR-429表达情况,探讨miR-429及CD133的表达与肿瘤的发生发展之间的关系。方法:采用荧光活化细胞分选法(FACS)分选出CD133不同亚群细胞,实时荧光定量PCR分别检测两组细胞miR-429的表达,合成miR-429寡核苷酸和阴性对照miRNA并分别转染CD133+和CD133-两个亚群细胞。再将细胞种植于非肥胖糖尿病/严重联合免疫缺陷(NOD/SCID)小鼠体内构建移植瘤模型,不同时间测量肿瘤体积和重量,RT-PCR及蛋白质印迹检测CD133+和CD133-两组肿瘤CD133mRNA和蛋白质表达。结果:血清检出CD133+细胞为67.9%,miR-429的表达量是CD133+细胞的(1.83±0.91)倍(P0.05),CD133+比例与miR-429表达呈负相关(r=0.591,P0.05);miR-429+/CD133+组的移植瘤体积及重量与对照组比较有统计学差异(P0.05),且miR-429+/CD133+组成瘤时间较对照组晚约2周,但miR-429+/CD133+组的移植瘤CD133表达量低,与阴性对照组比较无明显差异(P0.05)。结论:miR-429可能作为CD133的负性调控因子,具有抑制肿瘤生长的作用,但miR-429与CD133在肿瘤发生、发展过程中的作用机制有待进一步研究阐明。     

miR-224 在原发性肝癌患者血清中的表达及意义

目的：原发性肝癌(primary hepatocellular carcinoma, PHC) 作为常见的恶性程度极高的肿瘤,严重威胁着人类的生命。miR-224 是近年来发现的一个肿瘤相关miRNA 分子,在肿瘤的发生及发展过程中发挥着重要的作用。本研究通过测定原发性肝癌患者血清中miR-224 的表达水平,探讨血清miR-224 与原发性肝癌预后的关系。方法：采用实时荧光定量RT-PCR (Real-timeRT-PCR)方法,分别检测40 例原发性肝癌患者,20例慢性肝炎患者,20 例慢性肝硬化患者及20 例正常人的血清标本中miR-224的表达水平。分析血清miR-224 的表达水平与AFP和MMP-9的相关性。结果：原发性肝癌患者血清miR-224 的表达水平明显高于正常人、慢性肝炎和慢性肝硬化患者(P<0.05)。皮尔森相关分析结果显示原发性肝癌患者血清miR-224 的表达与AFP 和MMP-9 呈正相关。血清miR-224 低表达组术后复发/转移率显著低于高表达组,术后生存率则高于高表达组(P<0.01)。结论：miR-224 在原发性肝癌患者的血清中呈高表达,其血清表达水平与原发性肝癌的临床预后密切相关。这提示我们,miR-224 可能成为新的原发性肝癌检测标记物和潜在的原发性肝癌预后分子标志物。     

肝细胞癌肝移植患者血清miR-221检测及其临床意义

目的:探讨肝癌患者肝移植手术前后血清中miR-221的表达变化及其临床意义.方法:选择2009年6月至2011年8月在我院行肝移植手术的42例肝癌患者、26例肝良性疾病患者和40例正常对照组人员为研究对象,采用实时荧光定量RT-PCR(Real-time RT-PCR)对比检测移植前后患者血清中miR-221的表达水平.根据肝移植术前患者血清miR-221表达水平的平均值作为划分标准,将36例患者分为高表达组和低表达组.分析miR-221的表达与移植术后肿瘤复发和转移的关系.结果:原发性肝癌患者血清miR-221表达水平明显高于正常对照组(P＜0.05).移植术后患者血清miR-221的表达显著降低(P＜0.01).术前血清miR-221水平与肝移植术后HCC转移/复发情况密切相关.高表达组肝移植患者术后肝癌转移/复发率明显高于低表达组患者(P＜0.05);术后6月内肝癌复发患者血清miR-221水平显著高于未复发者(P＜0.05).结论:血清miR-221表达水平与肝癌肝移植术后肿瘤复发和转移密切相关,有可能成为肝癌肝移植预后的评估指标.     

MiRNA-221/222 对肝癌的影响研究进展

MicroRNAs(mi RNAs)在人类肿瘤致瘤生长机制的作用在肝细胞肝癌(hepatocellular carcinoma,HCC)中已经通过基因增殖和功能性研究所证实。肝癌中异常表达的miRNAs与其他类型的肿瘤有密切关系,其中较为独特的是上调的miR-221/222。MiR-221/222是高度同源基因,在HCC中明显上调,被认为是致瘤基因。本文对miR-221/222的分子及生物机制进行综述,并对其作为新的HCC诊断及治疗工具的可能性做出探讨。     

Diversity of Gene Expression in Hepatocellular Carcinoma Cells

Understanding tumor diversity has been a long-lasting and challenging question for researchers in the field of cancer heterogeneity or tumor evolution. Studies have reported that compared to normal cells, there is a higher genetic diversity in tumor cells, while higher genetic diversity is associated with higher progression risks of tumor. We thus hypothesized that tumor diversity also holds true at the gene expression level. To test this hypothesis, we used t-test to compare the means of Simpson's diversity index for gene expression(SDIG) between tumor and non-tumor samples.We found that the mean SDIG in tumor tissues is significantly higher than that in the non-tumor or normal tissues(P 0.05) for most datasets. We also combined microarrays and next-generation sequencing data for validation. This cross-platform and cross-experimental validation greatly increased the reliability of our results.     

肝细胞癌中miR-92a的表达及其对HepG2细胞凋亡的影响

目的:探讨miR-92a与肝细胞癌的相关性,及其表达改变对肝细胞癌HepG2细胞凋亡的影响.方法:实时定量PCR检测肝细胞癌和癌旁正常组织中miR-92a的表达;将miR-92a的抑制物miR-92a inhibitor转染了肝细胞癌HepG2细胞,然后检测了转染后细胞的凋亡.结果:与癌旁正常组织相比,肝细胞癌组织中miR-92a的表达显著上调;转染后miR-92a inhibitor组的凋亡率显著增加.结论:miR-92a与肝细胞癌的发生相关,抑制其表达能够促进肝细胞癌细胞凋亡,在肝细胞癌中发挥癌基因的作用.     

miR-221对于前列腺癌细胞的增殖及侵袭能力作用的研究

目的:研究miR-221不同时期前列腺癌细胞系中表达差异,探讨miR-221在雄激素非依赖前列腺癌的生长及侵袭能力中发挥的作用.方法:Northern检测雄激素依赖性与雄激素非依赖性前列腺癌细胞系中差异表达的miRNA.在不同前列腺癌细胞系中,通过CCK-8及流式细胞学检测基因转染前后miR-221对于前列腺癌细胞系的生长影响,以及通过侵袭实验检测细胞侵袭能力的变化.结果:①Northern显示LNCaP-AI细胞中miR-221水平明显高于LNCaP细胞;②miR-221促进LNCaP及LNCaP-AI细胞的增殖能力③下调miR-221会减弱LNCaP-AI细胞的侵袭能力.结论:miR-221促进不同时期前列腺癌细胞系的增殖,并增强LNCaP-AI的侵袭能力.     

Suppression of miR-221 inhibits glioma cells proliferation and invasion via targeting SEMA3B

Background

Gliomas are the most common primary tumors in the central nervous system. Due to complicated signaling pathways involved in glioma progression, effective targets for treatment and biomarkers for prognosis prediction are still scant.

Results

In this study we revealed that a new microRNA (miR), the miR-221, was highly expressed in the glioma cells, and suppression of miR-221 resulted in decreased cellular proliferation, migration, and invasion in glioma cells. Mechanistic experiments validated that miR-221 participates in regulating glioma cells proliferation and invasion via suppression of a direct target gene, the Semaphorin 3B (SEMA3B). The rescue experiment with miR-221 and SEMA3B both knockdown results in significant reversion of miR-221 induced phenotypes.

Conclusion

Taken together, our findings highlight an unappreciated role for miR-221 and SEMA3B in glioma.     

乳腺癌肿瘤干细胞的研究进展

干细胞(stem cell,SC)是一类具有自我更新、多向分化潜能的特殊细胞群体.而肿瘤干细胞(cancer stem cell,CSC)不仅具备了干细胞方面的特征,同时还有其自身特殊性.乳腺癌中肿瘤干细胞的发现为乳腺癌的治疗提供了创新性策略.近年来,有关乳腺癌肿瘤干细胞的筛选标记和方法以及信号转导通路方面的研究颇多,但其中也不乏争议.就乳腺癌干细胞研究的最新进展作一端述.     

MTA1 Overexpression Induces Cisplatin Resistance Innasopharyngeal Carcinoma by Promoting Cancer Stem Cells Properties

Themetastasis-associated gene 1 (MTA1) oncogene hasbeen suggested to be involved in the regulation of cancer progression. However, there is still no direct evidence that MTA1 regulates cisplatin (CDDP) resistance, as well as cancer stem cell properties. In this study, we found that MTA1 was enriched in CNE1/CDDP cells. Knock down of MTA1 in CNE1/CDDP cells reversed CSCs properties and CDDP resistance. However, ectopic expression of MTA1 in CNE1 cells induced CSCs phenotypes and CDDP insensitivity. Interestingly, ectopic overexpression of MTA1-induced CSCs properties and CDDP resistance were reversed in CNE1 cells after inhibition of PI3K/Akt by {"type":"entrez-nucleotide","attrs":{"text":"LY294002","term_id":"1257998346","term_text":"LY294002"}}LY294002. In addition, MTA1 expression and Akt activity in CNE1/CDDP cells was much higher than that in CNE1 cells. These results suggested that MTA1 may play a critical role in promoting CDDP resistance in NPC cells by regulatingcancer stem cell properties via thePI3K/Akt signaling pathway. Our findings suggested that MTA1 may be a potential target for overcoming CDDP resistance in NPC therapy.     

骨髓来源的间充质干细胞分化能力的鉴定

本文研究了人骨髓来源的间充质干细胞(MSCs)的成骨及成脂分化的潜能.通过加入诱导成骨的诱导剂,人的MSCs出现成骨分化的机箱,通过碱性磷酸酶活性测定,茜素红染色及主要调控基因BMP2和Runx2的表达,确定了MSCs具有成骨分化的潜能.对于成脂分化,通过油红O染色,及主要标志基因PPARγ的表达确定其具有成脂分化的潜能.所以,从骨髓分离的到的MSCs纯度达到标准,并且具有成骨成脂分化的多向潜能,是一种理想的实验模型细胞.     

Hepatocellular Carcinoma Cells Deteriorate the Biophysical Properties of Dendritic Cells

Dendritic cells (DCs) are potent antigen-presenting cells and induce antigen-specific immune responses in the organism. The dysfunction of DCs has been implicated in tumor-bearing host. In order to elucidate the effects of tumor microenvironment on the functions of DCs from interdisciplinary aspects, we characterized the biophysical properties of DCs co-cultured with hepatocellular carcinoma cells (HCC). The results showed that the biophysical characteristics of immature and mature DCs were severely impaired by HCC compared with those under normal conditions, including the increased osmotic fragilities, decreased cell membrane fluidities, increased membrane viscoelastic properties, dysfunction and increased expression of cytoskeleton protein F-actin, as well as the deteriorated transendothelium migration. The impaired biophysical properties of DCs may be one of many aspects of the immune escape mechanisms of tumors. These results are clinically and instructionally significant with regard to how to enhance efficiency of the anti-tumor therapy based on DCs. Zhu Zeng and Weijuan Yao contributed equally to this work.     

过表达微小RNA miR-125b对人胚胎干细胞增殖的影响

目的:通过在人胚胎干细胞(hESC)中有效转染微小RNA miR-125b的真核表达载体,研究过表达miR-125b对hESC增殖的影响。方法:将在无饲养层上培养至第3 d,克隆融合达70%的hESC用Accutase酶消化为单细胞,然后用LipofectAMINE2000对hESC单细胞转染pHRS-1cla-miR125b-CMV-EGFP载体及其对照pHRS-1cla-CMV-EGFP载体,通过实时定量PCR对转染后细胞中成熟miR-125b的表达进行检测;进一步进行细胞计数和克隆计数,对miR-125b表达上调的hESC的增殖情况进行分析。结果:实时定量PCR检测结果表明,细胞转染后72 h,miR-125b的表达上调1.45倍,说明hESC转染成功;克隆计数及细胞计数结果显示过表达miR-125b的hESC增殖受到明显抑制(P<001)。结论:转染miR-125b真核表达载体的hESC能够上调成熟miR-125b的表达,hESC中miR-125b的表达上调能明显抑制hESC的增殖。     

An Integrative Meta-analysis of MicroRNAs in Hepatocellular Carcinoma

We aimed to shed new light on the roles of microRNAs （miRNAs） in liver cancer using an integrative in silico bioinformatics analysis. A new protocol for target prediction and functional analysis is presented and applied to the 26 highly differentially deregulated miRNAs in hepatocellular carcinoma. This framework comprises： （1） the overlap of prediction results by four out of five target prediction tools, including TargetScan, PicTar, miRanda, DIANA-microT and miRDB （combining machine-learning, alignment, interaction energy and statistical tests in order to minimize false positives）, （2） evidence from previous microarray analysis on the expression of these targets, （3） gene ontology （GO） and pathway enrichment analysis of the miRNA targets and their pathways and （4） linking these results to oncogenesis and cancer hallmarks. This yielded new insights into the roles of miRNAs in cancer hallmarks. Here we presented several key targets and hundreds of new targets that are significantly enriched in many new cancer-related hallmarks. In addition, we also revealed some known and new oncogenic pathways for liver cancer. These included the famous MAPK, TGFβ and cell cycle pathways. New insights were also provided into Wnt signaling, prostate cancer, axon guidance and oocyte meiosis pathways. These signaling and developmental pathways crosstalk to regulate stem cell transformation and implicate a role of miRNAs in hepatic stem cell deregulation and cancer development. By analyzing their complete interactome, we proposed new categorization for some of these miRNAs as either tumor-suppressors or oncomiRs with dual roles. Therefore some of these miRNAs may be addressed as therapeutic targets or used as therapeutic agents. Such dual roles thus expand the view of miRNAs as active maintainers of cellular homeostasis.