微小RNA与肿瘤

近年来微小RNA（miRNA）逐渐成为肿瘤研究的热点。越来越多的研究表明,miRNA已涉及到肿瘤的发生和发展,miRNA的表达与肿瘤的病理进程具有相关性,大约有数百个miRNA在肿瘤中异常表达,miRNA在不同肿瘤中具有时空特异性的表达谱。     

微小RNA与人类肿瘤

微小RNA（microRNA,miRNA）是一类对基因具有调控功能的内源性非编码小分子RNA。目前认为miRNA在多种生物学过程中起着至关重要的作用,包括细胞增殖、分化、凋亡等。近年研究表明miRNA表达异常能导致疾病甚至肿瘤的发生,有类似于抑癌基因或癌基因的功能。因此,对miRNA的进一步研究为肿瘤的诊断和治疗开辟了新的路径。     

微小RNA与人类肿瘤

微小RNA(microRNA,miRNA)是一类对基因具有调控功能的内源性非编码小分子RNA.目前认为miRNA在多种生物学过程中起着至关重要的作用,包括细胞增殖、分化、凋亡等.近年研究表明miRNA表达异常能导致疾病甚至肿瘤的发生,有类似于抑癌基因或癌基因的功能.因此,对miRNA的进一步研究为肿瘤的诊断和治疗开辟了...     

微小RNA与肿瘤耐药

微小RNA(miRNA)对靶基因的异常调控可能参与肿瘤耐药机制,是肿瘤耐药性分子遗传学研究的重要进展及补充.研究表明,miRNA可能是肿瘤耐药网络性调控的重要组成部分,而且对多基因表达进行调控的能力使其具有高效性.因此,有望成为重要的肿瘤耐药相关分子标记物及治疗靶点.     

微小RNA miR-155在肿瘤中的研究

微小RNA miR-155在多种人体肿瘤中异常表达,与肿瘤的发生、发展及预后密切相关,被认为是癌性微小RNA(oncomiR).研究发现miR-155可通过抑制其靶基因如SHIP1、C/EBPβ、SOCS1、TP53INP1等促进肿瘤的增殖、侵袭及转移.检测miR-155的表达可对早期诊断恶性肿瘤提供重要依据,抑制其表达将成为肿瘤治疗的新方向.     

微小RNA与肿瘤

微小RNA(miRNA)是一类小分子的非编码调控的单链RNA,它参与有机体的生长、发育等多种生理过程.近年来研究表明肿瘤组织具有不同的miRNA表达,异常表达的miRNA影响了肿瘤细胞的发生、进展、分化、转移和复发.miRNA的不同表达不仅有助于肿瘤组织的诊断,而且可以指导预后.针对miRNA为靶点的动物学研究也发现,干扰某种miRNA表达可以减小肿瘤体积,抑制腹膜转移而发挥治疗作用.     

微小RNA与肿瘤相关性

微小RNA(miRNA)在动植物体内形成RNA沉默复合体,介导目的基因mRNA的切割与翻译抑制,产生转录后基因沉默效应,调控基因的表达,从而调节生物发育、细胞分化与凋亡,参与肿瘤、复杂遗传病的发生及其他生命过程。近年来,在有关miRNA和肿瘤发生研究领域取得了一系列进展。     

微小RNA与肿瘤相关性

微小RNA（miRNA）在动植物体内形成RNA沉默复合体,介导目的基因mRNA的切割与翻译抑制,产生转录后基因沉默效应,调控基因的表达,从而调节生物发育、细胞分化与凋亡,参与肿瘤、复杂遗传病的发生及其他生命过程。近年来,在有关miRNA和肿瘤发生研究领域取得了一系列进展。     

微小RNA:肿瘤耐药治疗新靶点

肿瘤的多药耐药(multidrug resistance,MDR)是临床化疗失败的主要原因之一,但其耐药性机制至今尚未完全阐明.最近研究表明,微小RNA(miRNA) 对多基因表达的调控具有高效性和特异性,对靶基因的异常调控可能构成肿瘤耐药机制,是肿瘤耐药复杂性调控的重要构成部分.因此,对微小RNA与肿瘤耐药性研究具有现实意义.本文对近年来微小RNA与各种肿瘤耐药的关系及微小RNA作为肿瘤治疗潜在靶点的研究进展作一综述.     

微小RNA：肿瘤耐药治疗新靶点

肿瘤的多药耐药（multidrug resistance,MDR）是临床化疗失败的主要原因之一,但其耐药性机制至今尚未完全阐明。最近研究表明,微小RNA（miRNA）对多基因表达的调控具有高效性和特异性,对靶基因的异常调控可能构成肿瘤耐药机制,是肿瘤耐药复杂性调控的重要构成部分。因此,对微小RNA与肿瘤耐药性研究具有现实意义。本文对近年来微小RNA与各种肿瘤耐药的关系及微小RNA作为肿瘤治疗潜在靶点的研究进展作一综述。     

microRNA Profile Associated with Positive Lymph Node Metastasis in Early-Stage Cervical Cancer

Lymph node metastasis (LNM) is an important prognostic factor in cervical cancer (CC). In early stages, the risk of LNM is approximately 3.7 to 21.7%, and the 5-year overall survival decreases from 80% to 53% when metastatic disease is identified in the lymph nodes. Few reports have analyzed the relationship between miRNA expression and the presence of LNM. The aim of this study was to identify a subset of miRNAs related to LNM in early-stage CC patients. Formalin-fixed paraffin-embedded tissue blocks were collected from patients with early-stage CC treated by radical hysterectomy with lymphadenectomy. We analyzed samples from two groups of patients—one group with LNM and the other without LNM. Global miRNA expression was identified by microarray analysis, and cluster analysis was used to determine a subset of miRNAs associated with LNM. Microarray expression profiling identified a subset of 36 differentially expressed miRNAs in the two groups (fold change (FC) ≥ 1.5 and p < 0.01). We validated the expression of seven miRNAs; miR-487b, miR-29b-2-5p, and miR-195 were underexpressed, and miR-92b-5p, miR-483-5p, miR-4534, and miR-548ac were overexpressed according to the microarray experiments. This signature exhibited prognostic value for identifying early-stage CC patients with LNM. These findings may help detect LNM that cannot be observed in imaging studies.     

A basal‐enriched microRNA is required for prostate tumorigenesis in a Pten knockout mouse model

MicroRNAs (miRNAs) play important roles in prostate cancer development. However, it remains unclear how individual miRNAs contribute to the initiation and progression of prostate cancer. Here we show that a basal layer‐enriched miRNA is required for prostate tumorigenesis. We identify miR‐205 as the most highly expressed miRNA and enriched in the basal cells of the prostate. Although miR‐205 is not required for normal prostate development and homeostasis, genetic deletion of miR‐205 in a Pten null tumor model significantly compromises tumor progression and does not promote metastasis. In Pten null basal cells, loss of miR‐205 attenuates pAkt levels and promotes cellular senescence. Furthermore, although overexpression of miR‐205 in prostate cancer cells with luminal phenotypes inhibits cell growth in both human and mouse, miR‐205 has a minimal effect on the growth of a normal human prostate cell line. Taken together, we have provided genetic evidence for a requirement of miR‐205 in the progression of Pten null‐induced prostate cancer.     

miRNAs与鼻咽癌研究进展

0 引言 微小RNA(miRNAs)是一类长度为21～30nt的高度保守的、内源性非编码蛋白质的单链小RNA分子~([1]).随着对miRNAs研究的深入,发现miRNAs调节人类1/3的基因,不仅参与个体发育、器官形成和物质代谢等生理过程,还与病毒复制和肿瘤发生等密切相关.     

Systemic mirnas as potential biomarkers for malignancy

MiRNAs are a class of short, endogenous, single‐stranded RNA molecules that play a role in the regulation of gene expression. They have been shown to modulate a number of cellular processes including cell differentiation, growth and apoptosis and as a result have been implicated in carcinogenesis. They are detectable in tumour tissue, and altered expression levels have been identified in various cancer types. Of interest, miRNAs have recently been detected and identified to be dysregulated in the circulation of patients with breast cancer. The fact that a minimally invasive test can distinguish the presence or absence of disease illustrates the immense potential these molecules hold as predictive markers. This review serves to identify those systemic miRNAs that are upregulated or downregulated in malignancy and how treatment impacts on their circulating levels. In addition, this review questions the source of these small molecules in the bloodstream and how they may possibly play a role in the future detection of cancer as either prognostic or predictive markers. © 147.     

microRNA与癌症发生相关性研究的现状

microRNAs简称miRNAs,是一类长约22核苷酸(nt)的非编码的单链RNA分子,由约70 nt的前体miRNA(pre-miRNA)经Dicer酶剪切而来.miRNA参与生命过程中一系列的重要进程,包括发育、造血、器官形成、凋亡和细胞增殖,甚至是癌症发生.目前人类基因组中已确认的miRNA约500个,其中至少有200多种miRNA序列与癌症发生有关.如miRNAs主要通过3种机制参与癌症发生:1)靶分子识别.以碱基互补的形式识别并结合靶分子,使其表达上升或下降,促进癌症的形成.miR-15a和miR-16-1特异性识别Bcl-2,直接与Bcl-2的3'UTR结合,使Bcl-2表达增加,抑制细胞凋亡或程序性细胞死亡通路,导致慢性淋巴性白血病等肿瘤发生.乳突状甲状腺癌患者组织中,与miR-221、miR-222结合的Kit的3'UTR端结合区域关键部位出现单核苷酸多态性(3169G→A),与miR-146a和miR-146b结合的外显子结合区域的关键部位出现单核苷酸多态性(2607G→C),从而导致Kit转录下降和Kit蛋白水平低下,促进乳突状甲状腺癌的形成.2)miRNAs突变或含有miRNAs染色体片断缺失.含有miR-15、miR-16基因片断缺失或者miR-15a和miR-16-1发生突变,与人慢性淋巴性白血病进展和预后有关,miR-17-92基因簇刺激肺癌细胞生长.3)癌基因或抑癌基因.肺癌组织中let-7 miRNA调控RAS癌基因的表达,成胶质细胞瘤中miR-21以微癌基因形式发挥作用,乳腺癌中miR-10b、miR-125b、miR-145和miR-21及miR-155分别以抑癌基因和癌基因的形式发挥作用.     

Clinical evaluation of microRNA expression profiling in non small cell lung cancer

Deregulation of miRNAs expression levels has been detected in many human tumor types, and recent studies have demonstrated the critical roles of miRNAs in cancer pathogenesis. Numerous recent studies have shown that miRNAs are rapidly released from tissues into the circulation in many pathological conditions. The high relative stability of miRNAs in biofluids such as plasma and serum, and the ability of miRNA expression profiles to accurately classify discrete tissue types and disease states have positioned miRNAs as promising non-invasive new tumor biomarkers. In this study, we used liquid bead array technology (Luminex) to profile the expression of 320 mature miRNAs in a pilot testing group of 19 matched fresh frozen cancerous and non-cancerous tissues from NSCLC patients. We further validated our results by RT-qPCR for differentially expressed miRNAs in an independent group of 40 matched fresh frozen tissues, 37 plasma samples from NSCLC patients and 28 healthy donors.     

微小RNA与肿瘤血管生成

 肿瘤细胞表达的相关微小RNA（miRNA）通过调控血管内皮生长因子（VEGF）的表达,影响肿瘤血管生成,而血管生成在肿瘤的生长发展等过程中起着十分重要的作用。因此深入研究miRNA的功能将为抑制肿瘤血管生成提供更有效的靶点,为肿瘤的临床诊治提供更可靠的依据。     

microRNA与肺癌

目前,我国肺癌的发病率及死亡率迅速增高,已跃居城市人口恶性肿瘤死亡原因的第一位。microRNA(miRNA)是一类新近发现的长约18-25个核苷酸的非编码小分子RNA,是哺乳动物基因组中最为丰富的调节基因之一,可能调控着至少1/3的人类编码蛋白基因[1-3]。