微小RNA与肿瘤耐药

微小RNA(miRNA)是近年来在真核生物中发现的、在转录后水平负调控基因表达的一类长约22个核苷酸的非编码小分子RNA.miRNA生物学效应广泛,与细胞生长、凋亡、新陈代谢和信号转导等密切相关.已报道miRNA在各种肿瘤中表达失常,可能发挥着癌基因和抑癌基因的双重作用,同时越来越多的研究表明miRNA在调节肿瘤细胞对抗肿瘤药物耐药方面发挥着重要作用.系统深入地研究miRNA在肿瘤耐药中的机制,将为发展基于miRNA逆转肿瘤耐药的治疗策略提供重要的依据.     

微小RNA与肿瘤耐药

微小RNA(miRNA)是近年来在真核生物中发现的、在转录后水平负调控基因表达的一类长约22个核苷酸的非编码小分子RNA.miRNA生物学效应广泛,与细胞生长、凋亡、新陈代谢和信号转导等密切相关.已报道miRNA在各种肿瘤中表达失常,可能发挥着癌基因和抑癌基因的双重作用,同时越来越多的研究表明miRNA在调节肿瘤细胞对抗肿瘤药物耐药方面发挥着重要作用.系统深入地研究miRNA在肿瘤耐药中的机制,将为发展基于miRNA逆转肿瘤耐药的治疗策略提供重要的依据.     

miR-21作用于PTEN与肿瘤耐药关系的研究进展

miRNA(microRNA)是一类非编码的微小RNA,其成熟体通过与靶mRNA 3' 端非编码区特异性结合,可在翻译和转录后水平调控靶基因的表达。有研究表明miRNA与细胞的发展、分化、凋亡和增殖有着密切的关系。miR-21(microRNA-21)作为miRNA的一个重要分子,在肿瘤的形成和耐药中发挥着重要作用。在众多耐药肿瘤细胞中,miR-21通过下调靶基因PTEN从而抑制肿瘤细胞的凋亡,增加肿瘤细胞的生长、转移和侵袭。本文就miR-21通过作于其靶基因PTEN与肿瘤耐药的关系作一综述。     

肿瘤相关微小RNA与凋亡

微小RNA(miRNA) 在转录后水平调控基因的表达.研究证实miRNA通过调控细胞的凋亡,在肿瘤的发生发展过程中发挥着重要的作用.肿瘤相关miRNA与凋亡的研究在未来的肿瘤诊疗中miRNA可能具有广阔的应用前景.     

微小RNA在肿瘤干细胞中的研究进展

肿瘤干细胞学说（tumorstemcells,TSCs）认为肿瘤组织中存在一小部分细胞具有干细胞特性,具有自我更新和多向分化的潜能,是肿瘤形成、发展、转移及复发的根本原因。最近的研究发现微小RNA（miRNA）在维持肿瘤干细胞生物学特性方面发挥着重要作用。探讨miRNA参与调控肿瘤干细胞特性的分子机制,具有重要的理论意义。     

miRNA在子宫内膜癌发病机制中的研究进展

微小RNA(miRNA)是一种重要的内源性非编码RNA,在动植物及病毒中广泛存在。miRNA与肿瘤的发生、发展和预后关系密切,并参与肿瘤细胞的增殖、分化及凋亡。许多miRNA在肿瘤的形成过程中发挥着原癌基因或抑癌基因的作用。子宫内膜癌为妇科三大恶性肿瘤之一,其发病率逐年上升。现就miRNA在子宫内膜癌发病机制方面的研究进展作一简要综述。     

微RNA在儿童B系淋巴细胞白血病、淋巴瘤中的研究进展

 【摘要】　微RNA（miRNA）是近年来发现的一类新的非编码小分子RNA，miRNA在淋巴造血系统肿瘤的发生、发展及预后中发挥着重要的调节作用。文章就miRNA的产生、作用机制及其在儿童B系淋巴细胞白血病、淋巴瘤中的研究进展进行综述。     

微RNA 221/222在乳腺癌中的研究进展

微RNA(miRNA)是细胞内源性长度为19~25个核苷酸的单链非编码小RNA分子,广泛存在于真核生物中,通过碱基互补配对的方式对多个靶基因表达起负调控作用,激活下游信号通路,影响肿瘤的发生、发展、侵袭、转移和耐药等生物学过程。其中,微RNA 221/222(miR-221/222)在乳腺癌细胞的增殖、侵袭、转移以及耐药等过程中发挥着重要作用。笔者就近年来miR-221/222在乳腺癌方面的研究进展做一综述。     

微RNA与肿瘤

微RNA(miRNA)是一类非编码的小RNA分子,通过直接抑制基因转录或蛋白质的表达而在器官发育,细胞增殖、分化和凋亡等多种生理过程中发挥关键作用.miRNA异常表达往往导致包括肿瘤在内的多种疾病.研究发现,miRNA在肿瘤发生发展、侵袭转移及肿瘤的诊治中起着重要作用.     

miRNA-148a与肿瘤

0 引言 当今,放化疗及生物靶向治疗已明显提高了肿瘤患者的生存期,但是肿瘤的复发、侵袭转移以及耐药等恶性行为仍是导致治疗失败与死亡的重要原因.microRNA(miRNA)是一类能调控基因表达的非编码蛋白RNA,通过调控mRNA表达和翻译的方式发挥作用.异常表达的miRNA广泛参与肿瘤的发生、发展、侵袭转移及耐药等演进过程.miRNA-148a作为miRNA中的一员,研究发现miRNA-148a在多种肿瘤中表达降低,主要发挥抑癌基因样作用,抑制并逆转肿瘤的恶性表型,其临床价值也越来越受到重视.     

MicroRNA-21: a novel therapeutic target in human cancer

Resistance to anticancer agents is the major clinical obstacle to the successful treatment of cancer, yet the mechanisms underlying drug resistance have not been fully characterized. MicroRNAs (miRNAs) are endogenous, small (19-25 nucleotides in length) noncoding RNAs, which function by base pairing with messenger RNAs, thereby regulating protein expression. Emerging evidence shows that alteration of miRNAs is involved in cancer initiation and progression. MiR-21 is a miRNA that is overexpressed in most tumor types, and acts as an oncogene by targeting many tumor suppressor genes related to proliferation, apoptosis, and invasion. In vivo and in vitro studies suggest that miR-21 may serve as a diagnostic and prognostic marker for human malignancies. More recently, studies have identified an important role for miR-21 in anticancer drug resistance. Here, we review the mechanisms underlying miR-21-mediated chemoresistance and the potential use of miR-21 as a novel molecular target for cancer chemotherapy.     

微小RNA与卵巢癌铂类耐药的研究进展

微小RNA(micmRNA,miBNA)是广泛存在于生物体内的一类非编码的小RNA,miRNA是细胞增殖、死亡、应激抗性和脂肪代谢的关键调节因素,体外实验已经证实miRNA在卵巢癌耐药中起重要作用.卵巢癌铂类耐药的产生与发展是十分复杂的过程,研究结果显示,miRNA的表达对卵巢癌细胞株的铂类药物敏感性有着重要作用,能够...     

miR-155-5p在肿瘤中的表达、功能以及调控作用

MicroRNA(miRNA)是一类小的、单链非编码RNA,作为与基因表达相关的调控因子参与生命过程中的一系列重要进程。目前,已有大量研究表明miRNA的表达失调可能是人类肿瘤产生和发展机制中的重要一环。多数情况下,miR-155-5p作为一种促肿瘤microRNA,可以通过作用于多个靶基因参与肿瘤的发展进程,但也有一些研究指出该miRNA也具有抑癌基因的功能。本文对miR-155-5p在各类型肿瘤中对癌细胞增殖、侵袭、迁移和耐药的影响,以及作为可能的潜在标志物在协助诊断方面的价值作一综述。     

循环miRNAs在肺癌诊断和治疗中的研究进展

肺癌是全世界男性和女性癌症死亡的第一原因。尽管近些年对癌症信号通路的了解和在新的治疗方法开发上有了新进展,但是肺癌的不良预后和高复发率依然存在。循环miRNAs在许多实体瘤（如肺癌）中,可作为稳定表达的非侵入性诊断标志物。一些miRNAs异常可能与肿瘤细胞常规化疗的耐药性有关,影响着肿瘤细胞的药物敏感性。这些miRNAs的调控,通过使用miRNAs类似物,可以调节关键基因网络和信号通路,通过抑制肿瘤细胞增殖来提高抗癌治疗的疗效,增加药物敏感性。因此,miRNAs疗法提供了新的抗肿瘤方法:更有效的个性化治疗、提高药物疗效、预测不同抗癌药物的反应。本综述的目的是为肺癌循环miRNA提供一个作为潜在诊断生物标志物、大规模临床筛选诊断的可行性评估以及miRNAS抗癌耐药机制对肺癌的治疗的概述。最后,miRNA分析的局限性和潜在性需要今后进一步探索。     

MicroRNAs

MicroRNAs (miRNAs) are small, noncoding RNAs with regulatory functions, which play an important role in many human diseases, including cancer. An emerging number of studies show that miRNAs can act either as oncogenes or as tumor suppressor genes or sometimes as both. Germline, somatic mutations and polymorphisms can contribute to cancer predisposition. miRNA expression levels have diagnostic and prognostic implications, and their roles as anticancer therapeutic agents is promising and currently under investigation.     

Microarray-based analysis: identification of hypoxia-regulated microRNAs in retinoblastoma cells

Hypoxia is an essential feature of retinoblastoma and contributes to poor prognosis and resistance to conventional therapy. MicroRNAs (miRNAs) are small non-coding RNAs involved in a wide variety of biological processes, including cell differentiation, proliferation, death and metabolism. However, the relationship between hypoxia and the expression of miRNAs in retinoblastoma is not well understood. In this study, we aimed to analyze the pattern of miRNA expression in a retinoblastoma cell line under hypoxic conditions and to identify the miRNAs regulated by hypoxia, as well as their possible functions. miRNA expression profiling in retinoblastoma cells (HXO-RB44) under normal and hypoxic conditions was assessed by microarray techniques. The differentially expressed miRNAs were subjected to bioinformatic analyses to predict and categorise the key miRNAs and their target genes. A quantitative real-time RT-PCR approach was used to validate their expression. A Cell Counting kit was used to evaluate the functional significance of miR-181b in RB cell proliferation. There were 46 miRNAs that changed expression more than 2-fold in response to hypoxia (34 up-regulated and 12 down-regulated). We identified a cluster of miRNAs that includes miR-181b, miR-125a-3p, miR-30c-2, miR-497 and miR-491-3p as hypoxia-regulated miRNAs (HRMs) in retinoblastoma cells, of which miR-181b was the most typically differentially expressed miRNA under hypoxic conditions. Functionally, these HRMs are involved in apoptosis, cell adhesion, cell proliferation and mRNA processing, all processes that associate closely with the hypoxia response of cancer cells. Additionally, we found that administration of miR-181b inhibitor can suppress proliferation of retinoblastoma cells. These findings provide the first evidence that miRNAs play an important role in the hypoxia response of retinoblastoma cells. MiR-181b, the most typically up-regulated miRNA may aid in future clinical intervention of retinoblastoma.