Effect of high-dose benzo (a)pyrene on microRNAs expression in mice lung tissues

目的:研究长期高剂量苯并(a)芘[B(a)P]染毒对小鼠肺组织miRNAs表达谱的影响,探讨miRNAs在B(a)P健康损害过程中的作用.方法:40只1CR小鼠随机分为对照组和染毒组,每组20只,雌雄各半.经口灌胃给予小鼠50 mg/kg B (a)P,每周2次,持续8周,对照组同时给予等量的橄榄油,染毒结束后继续饲养8周.取肺脏组织,提取总RNA,采用SOliD高通量测序技术检测miRNAs表达谱,进行miRNAs差异表达分析,并用real time-PCR验证miRNAs表达,TargetScan,miRanda及picTar软件预测miRNAs可能调控的靶基因.结果:绝大部分miRNAs在肺组织的表达信号强度较低.与对照组相比,B(a)P染毒组小鼠肺组织中共有109个miRNAs发生差异表达,其中50个miRNAs表达上调,59个miRNAs表达下调.上调幅度最大的为7.43倍,下调幅度最大的为40.63倍.为验证测序的结果,取下调较为明显的miR-20b进行real time-PCR分析,结果显示与测序结果相一致,靶基因预测显示miR-20b可能调节与细胞增殖、周期、凋亡及肿瘤发生相关的蛋白.结论:长期高剂量B(a)P染毒可引起小鼠肺组织miRNAs表达产生特异性改变,差异表达miRNAs可能在B(a)P致机体健康损害过程中起着重要作用.     

胃癌miRNAs表达谱及胃癌组织miR-21表达临床意义探讨

目的:筛选胃癌miRNAs表达谱,探讨miR-21在胃癌组织中的表达情况及其临床病理意义.方法:收集手术切除新鲜胃癌标本共65例,包括胃癌组织及相应胃正常上皮组织,随机选取其中6例,应用miRNA芯片技术研究胃癌的miRNAs表达谱.采用实时定量PCR验证芯片结果并检测miR-21在65例胃癌组织标本及相应胃正常上皮组织的表达水平,探讨其表达与胃癌临床病理参数间的关系.结果:与胃正常上皮组织相比,胃癌组织中表达上调超过2倍的miRNAs有7个(miR-374b*、miRPlus-E1212、miR-338-5p、miR-297、miR-21、miR-135b和miR-18a),表达下调超过2倍的miRNAs有9个(miR-29b-2*、miR-1260、miRPlus-E1241、miR-S1-5p、miR-148a、miR-29c、miR-647、miR-196b×和ebv-miR-BART5).46例(70.8％)胃癌组织中miR-21表达水平明显高于胃正常上皮组织,且与肿瘤的分化程度(x2=6.257,P=0.012)、浸润深度(x =5.705,P=0.017)和有无淋巴结转移(x2=7.107,P=0.008)有关.结论:筛选出的差异表达miRNAs可能参与胃癌的发病;miR-21与胃癌生物学行为密切相关,可能成为胃癌诊断和治疗的潜在生物学指标.     

裸鼠荧光原位移植非小细胞肺癌模型转移相关microRNAs的研究

目的:筛选与非小细胞肺癌(NSCLC)转移相关的microRNAs,为研究其在转移过程中发挥的作用提供理论基础.方法:用荧光转染的人NSCLC细胞株H460皮下成瘸后原位移植于裸鼠左肺获取原发灶与转移灶组织标本.通过microRNA芯片检测和RT-PCR验证筛选与转移相关的差异microRNAs,并对其做生物信息学分析.结果:NSCLC有转移原发灶比无转移原发灶(A组)上调的microRNAs共17个,下调的7个;转移灶比转移原发灶(B组)上调的microRNAs共20个,下调的16个.A组中表达上调的有miR-10b和miR-144,下调的有miR-9、miR-31和miR-34b;B组中表达下调的有miR-25、miR-92a、miR-202和miR-326,它们可能受转录因子AP-1、p53、STATs和NF-cB等调控,作用于RARβ、RASSF1和E2F-1等靶基因,发挥调控细胞增殖周期、细胞发育过程、DNA和RNA代谢及信号传导通路的作用,促进肿瘤生长和转移.结论:在NSCLC有转移和无转移组织中microRNA的表达谱存在差异,它们通过多种途径对肿瘤细胞的增殖、黏附、迁移和漫润起调控作用.     

卵巢浆液性囊腺癌化疗耐药和化疗敏感组织中的miRNAs差异表达谱检测及生物信息学分析

目的:寻找卵巢浆液性囊腺癌化疗耐药及化疗敏感组织中microRNA的差异表达,为研究上皮性卵巢癌化疗耐药产生的分子机制及逆转其化疗耐药提供理论基础和依据.方法:首先,应用microRNA表达谱基因芯片寻找卵巢浆液性囊腺癌化疗耐药及化疗敏感组织中差异表达的microRNAs;其次,选取部分差异表达的microRNAs应用RT-PCR实验检测技术在扩大的组织样本中进行验证;最后,运用生物信息学技术对符合要求的microRNAs进行相关生物信息学分析.结果:在microRNA表达谱基因芯片中筛选出与卵巢浆液性囊腺癌化疗耐药相关的miR-27a-3p、miR-141-3p、miR-200b-3p等17个表达上调的miRNAs和miR-93-3p、 miR-497-5p、miR-675-3p等15个表达下调的miRNAs.上调miRNAs预测的靶基因GO(BP模块)分析结果显示凋亡信号通路、Notch信号通路和凋亡过程,KEGG Pathway分析结果显示Wnt信号通路、PI3K-Akt信号通路和ErbB信号通路可能与化疗耐药存在相关性.下调miRNAs预测的靶基因GO(BP模块)分析结果显示负调控凋亡过程、Wnt信号通路生物学过程,KEGG Pathway分析结果显示PI3K-Akt信号通路、细胞循环可能与化疗耐药存在相关性.结论:MicroRNA表达谱基因芯片及生物信息学技术能为研究上皮性卵巢癌化疗耐药产生机制提供新的思路.miR-27a-3p、miR-141-3p、miR-200b-3p、miR-93-3p、miR--p、miR--p可能分别通过调控靶基因PRKCB、MAPK、PAK、PRKAA、CCNE、IGFR参与卵巢浆液性囊腺癌化疗耐药.     

PM2.5染毒HBE细胞前后差异表达的microRNAs及其生物信息学分析

目的：采用microRNA（miRNA）测序和生物信息学方法,分析大气细颗粒物（PM_2.5）染毒人支气管上皮HBE细胞前后差异表达的miRNAs,预测差异miRNAs的生物学功能和信号转导途径。方法：用50 μg/mL的PM_2.5混悬液染毒HBE细胞,以未染毒组作为对照组,处理24 h后提取总RNA样品,Small RNA样品预处理试剂盒构建文库,并利用illumina HiSeq^TM 2500/MiSeq测序平台进行高通量测序。以调整后P < 0.05的筛选标准得到差异miRNAs,使用miRanda和RNAhybrid两个软件共同预测差异miRNAs的靶基因并进行GO和KEGG功能富集分析,利用STRING数据库和Cytoscape软件对miRNAs和靶基因及靶基因之间的相互作用关系进行可视化分析。结果：高通量测序方法共检测到PM_2.5染毒前后的包含1 137个miRNAs的表达谱,27个为差异表达的miRNAs,其中7个上调,20个下调。GO和KEGG富集分析发现,这些差异miRNAs主要参与细胞代谢、酶活性调节等生物学过程,聚集于胞内如细胞质、细胞器等,涉及代谢途径、PI3K-Akt信号通路、Ras信号通路、MAPK信号通路等与细胞增殖、分化、凋亡及癌症发生等相关的重要信号通路。此外,通过构建相互作用网络图,鉴定了miR-371b-3p、miR-371a-5p、miR-27a-3p、miR-7-5p、miR-372-3p等相互作用数量前11位的核心miRNAs,以及3个核心靶基因（VEGFA、MAPK3、CCR5）。结论：PM_2.5染毒HBE细胞后引起了27个miRNAs的差异表达,涉及PI3K-Akt信号通路、Ras信号通路及MAPK信号通路等与癌症发生发展相关的重要信号通路,其中筛选了11个核心miRNAs和3个核心基因,为深入研究PM_2.5致癌毒理作用机制提供了实验依据。     

miR-20a通过靶向抑制PTEN诱导肝癌细胞放射抵抗

目的 探讨miR-20a在肝癌放射敏感性中的作用及机制。方法 荧光定量PCR检测肝癌细胞系和组织标本中miR-20a的表达;构建稳定过表达miR-20a肝癌细胞系,通过克隆实验探讨miR-20a对肝癌细胞放射敏感性影响;蛋白印记法检测Bcl-2、Caspase-3以及γ-H2AX的表达;生物信息学预测miR-20a下游调控的靶基因,双荧光素酶报告系统、荧光定量PCR及蛋白印记法进一步验证;在稳定过表达miR-20a的肝癌细胞系中转染pCDNA3.0-PTEN探讨细胞放射敏感性的变化,明确PTEN是否为miR-20a诱导肝癌放射抵抗的一个功能性靶基因。结果 miR-20a在肝癌细胞系和组织标本中表达上调(P<0.05);经过同等条件的放射处理后,与空白及对照组(WT组、LV-con组)相比,过表达miR-20a组(LV-miR-20a组)细胞存活分数升高,放射抵抗增强(P<0.05),Bcl-2表达上调,Caspase-3及γ-H2AX表达下调;过表达PTEN能够逆转miR-20a引起的放射抵抗。结论 miR-20a在肝癌细胞系及组织标本中表达上调;过表达miR-20a可以促进肝癌细胞放射抵抗,PTEN是miR-20a诱导肝癌放射抵抗的一个功能性靶基因,预示着miR-20a/PTEN位点可能是是肝癌临床放疗相关的有效分子靶点。     

PM2.5染毒HBE细胞前后差异表达的microRNAs及其生物信息学分析

目的：采用microRNA（miRNA）测序和生物信息学方法，分析大气细颗粒物（PM_2.5）染毒人支气管上皮HBE细胞前后差异表达的miRNAs，预测差异miRNAs的生物学功能和信号转导途径。方法：用50 μg/mL的PM_2.5混悬液染毒HBE细胞，以未染毒组作为对照组，处理24 h后提取总RNA样品，Small RNA样品预处理试剂盒构建文库，并利用illumina HiSeq^TM 2500/MiSeq测序平台进行高通量测序。以调整后P < 0.05的筛选标准得到差异miRNAs，使用miRanda和RNAhybrid两个软件共同预测差异miRNAs的靶基因并进行GO和KEGG功能富集分析，利用STRING数据库和Cytoscape软件对miRNAs和靶基因及靶基因之间的相互作用关系进行可视化分析。结果：高通量测序方法共检测到PM_2.5染毒前后的包含1 137个miRNAs的表达谱，27个为差异表达的miRNAs，其中7个上调，20个下调。GO和KEGG富集分析发现，这些差异miRNAs主要参与细胞代谢、酶活性调节等生物学过程，聚集于胞内如细胞质、细胞器等，涉及代谢途径、PI3K-Akt信号通路、Ras信号通路、MAPK信号通路等与细胞增殖、分化、凋亡及癌症发生等相关的重要信号通路。此外，通过构建相互作用网络图，鉴定了miR-371b-3p、miR-371a-5p、miR-27a-3p、miR-7-5p、miR-372-3p等相互作用数量前11位的核心miRNAs，以及3个核心靶基因（VEGFA、MAPK3、CCR5）。结论：PM_2.5染毒HBE细胞后引起了27个miRNAs的差异表达，涉及PI3K-Akt信号通路、Ras信号通路及MAPK信号通路等与癌症发生发展相关的重要信号通路，其中筛选了11个核心miRNAs和3个核心基因，为深入研究PM_2.5致癌毒理作用机制提供了实验依据。     

萎缩性骨不连中miRNAs的异常表达与其靶基因的初步预测

目的筛选研究萎缩性骨不连断段修复组织中异常表达的microRNAs（miRNAs）,并对其可能的功能性靶基因进行预测分析。方法以萎缩性骨不连患者断端瘢痕组织（AN,3例）与正常骨折愈合后内固定钢板取出时钢板周围的骨痂组织（B组,3例）作为研究对象,采用Exiqon miRCURY^TM LNA microRNA芯片（11．0版）进行筛选分析,比较A组组织中是否存在异常表达的miRNAs,并采用浏览计算机预测数据库等生物信息学的方法预测其可能的靶基因,探寻miRNAs可能参与的萎缩性骨不连相关病理生理过程。结果A组相对B组有9种miRNAs发生1．5倍以上表达上调（hsa—miR-149,hsa—miR-221,hsa—miR-628—3p,hsa-miR-54—5p,以及5种hsa—miRPlus）,9种miRNAs发生1．5倍以上表达下调（hsa—let-7b＊,hsa—miR-220b,hsa—miR-513a-3p,hsa—miR-551a,hsa—miR-576-5p,hsa—miR-1236,kshv—miR—K12—6—5p,以及2种hsa—miRPlus）。生物信息学分析发现,表达异常的miRNAs与多数成骨基因存在作用靶点。结论萎缩性骨不连的断端修复组织存在miRNAs的异常表达,其靶基因包括BMP家族在内的众多成骨性基因。数种miRNAs,特别是4种上调的miRNAs（hsa-miR-149＊、hsa-miR-221、hsa-miR-628—3p和hsa—miR-654—5p）有可能在调控骨折向不愈合发展中具有重要作用。     

miR-200a抑制YAP1基因表达对肺癌细胞增殖的影响

  目的   研究微小RNA-200a（miR-200a）对肺癌细胞增殖的影响,并探讨其分子机制。   方法   采用Real-time PCR检测15例非小细胞肺癌组织和对应癌旁组织、人肺癌细胞株（A549、NCI-H520、SK-MES-1）及人正常肺支气管上皮细胞株16HBE中miR-200a的表达水平。用CCK-8法检测miR-200a对A549肺癌细胞增殖活性的影响。通过生物信息学方法预测miR-200a可能的靶基因,双荧光素酶报告基因实验结合Real-time PCR和Western blot验证miR-200a对靶基因YAP1的调控作用。CCK-8法检测下调靶基因YAP1对A549肺癌细胞株增殖活性的影响。   结果   miR-200a在非小细胞肺癌组织和肺癌细胞系中表达明显降低（P < 0.01）。上调miR-200a表达后明显抑制A549肺癌细胞的增殖活力（P < 0.01）。双荧光素酶报告基因显示miR-200a可以直接作用于靶基因YAP1的3'-UTR区域抑制荧光素酶活性（P < 0.01）,Real-time PCR和Western blot检测显示上调miR-200a的表达能够明显下调A549肺癌细胞YAP1 mRNA和蛋白的表达水平（P < 0.01）。CCK-8法显示下调YAP1的表达能够明显抑制A549肺癌细胞的增殖活性（P < 0.01）。   结论   miR-200a通过靶向作用于YAP1基因来抑制肺癌细胞的增殖,从而在肺癌中发挥抑癌基因的功能。      

大规模平行测序技术筛选人肾细胞癌组织中差异表达microRNAs及其验证

目的:以大规模平行测序技术(massively parallel signature sequencing,MPSS)筛选人肾细胞癌(renal cell carcinoma,RCC)和癌旁组织中差异表达的microRNAs(miRNAs),并验证差异表达miRNAs之一的miR-660在人RCC中的表达。方法:MPSS检测10例RCC组织及相应癌旁组织中miRNAs的表达,筛选RCC组织中差异表达miRNAs。RT-PCR检测5例RCC与癌旁组织中miR-660的表达,qPCR检测40例RCC与癌旁组织中miR-660的表达。结果:MPSS结果显示,RCC组织中283个miRNAs表达下调,187个表达上调,其中miR-660在RCC组织中表达量是癌旁组织的17.5%。RT-PCR初步验证了此结果;qPCR验证结果显示,40例RCC组织中33例miR-660表达显著低于癌旁组织,RCC组织中miR-660平均表达量是癌旁的19.5%。结论:人RCC组织中283个miRNAs表达下调、187个上调。miR-660在RCC组织中低表达,有可能成为RCC诊断及治疗的新靶点。     

Differential expression of microRNAs in early-stage neoplastic transformation in the lungs of F344 rats chronically treated with the tobacco carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone

While numerous microRNAs (miRNAs) have been reported to alter their expression levels in human lung cancer tissues compared with normal tissues, the function of these miRNAs and their contribution to the long process of lung cancer development remains largely unknown. We applied a tobacco-specific carcinogen-induced cancer model to investigate the involvement of miRNAs in early lung cancer development, which could also provide information on potential, early biomarkers of lung cancers. Male F344 rats were first chronically treated with 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), a carcinogen present in tobacco products, for up to 20 weeks. The expression profiles of miRNAs in rat lungs were then determined. As measured by miRNA microarrays and confirmed by Northern blot and real-time polymerase chain reaction analyses, NNK treatment reduced the expression of a number of miRNAs, such as miR-101, miR-126*, miR-199 and miR-34. Significantly, these miRNAs overlap with previously published reports on altered miRNA expression in human lung cancer samples. These miRNAs might, therefore, represent early-response miRNAs that signify the molecular changes associated with pulmonary tumorigenesis. Moreover, we identified cytochrome P450 (CYP) 2A3, a critical enzyme in rat lungs that activates NNK to render it carcinogenic, as a potential target of miR-126*. NNK treatment in rats repressed miR-126* but induced CYP2A3 expression, a mechanism that may potentiate the oncogenic effects of NNK.     

Inhibition of benzo[a]pyrene-induced mutagenesis by (-)-epigallocatechin gallate in the lung of rpsL transgenic mice

Epigallocatechin gallate (EGCG) is a major water-soluble component of green tea. The antimutagenic activity of EGCG against benzo[a]pyrene (B[a]P)-induced mutations was assessed by using transgenic mice carrying the rpsL gene as a monitor of mutations. Seven-week-old male mice were given drinking water containing EGCG for 3 weeks. On day 7, mice were treated with a single i.p. injection of B[a]P (500 mg/kg body wt). Two weeks after the injection, the mutations in the rpsL gene were analyzed. B[a]P treatment resulted in an approximately 4-fold increase of mutation frequency at the rpsL gene in the lung. An approximately 60% reduction in the B[a]P-induced mutations in the lung was observed when mice were given EGCG at concentrations >0.005%. B[a]P-induced mutations mainly occurred at G:C basepairs in the several specific nucleotide sequences of the rpsL gene. These were AGG, CGG, CGT, TGG, TGC and GGT: all of them contained a guanine residue. Mutations seen similarly in the human Ki-ras codon 12 or p53 codons 157, 248, and 273 of lung tumor were also found in the rpsL gene, and the mutations were suppressed by the EGCG treatment. In conclusion, the antimutagenic effects of EGCG for B[a]P-induced mutagenesis in vivo suggest that drinking green tea may reduce the tumor-initiating potency of B[a]P in the lung.     

Plasma Circulating Mirnas Profiling for Identification of Potential Breast Cancer Early Detection Biomarkers

Objective: This study aimed to characterize the miRNA expression profiles from plasma samples of our local breast cancer patients in comparison to healthy control by using miRNA PCR Array. Methods: In this study, plasma miRNA profiles from eight early-stage breast cancer patients and nine age-matched (± 2 years) healthy controls were characterized by miRNA array-based approach, followed by differential gene expression analysis, Independent T-test and construction of Receiver Operating Characteristic (ROC) curve to determine the capability of the assays to discriminate between breast cancer and the healthy control. Results: Based on the 372-miRNAs microarray profiling, a set of 40 differential miRNAs was extracted regarding to the fold change value at 2 and above. We further sub grouped 40 miRNAs of breast cancer patients that were significantly expressed at 2-fold change and higher. In this set, we discovered that 24 miRNAs were significantly upregulated and 16 miRNAs were significantly downregulated in breast cancer patients, as compared to the miRNA expression of healthy subjects. ROC curve analysis revealed that seven miRNAs (miR-125b-5p, miR-142-3p, miR-145-5p, miR-193a-5p, miR-27b-3p, miR-22-5p and miR-423-5p) had area under curve (AUC) value > 0.7 (AUC p-value < 0.05). Overlapping findings from differential gene expression analysis, ROC analysis, and Independent T-Test resulted in three miRNAs (miR-27b-3p, miR-22-5p, miR-145-5p). Cohen’s effect size for these three miRNAs was large with d value are more than 0.95. Conclusion: miR-27b-3p, miR-22-5p, miR-145-5p could be potential biomarkers to distinguish breast cancer patients from healthy controls. A validation study for these three miRNAs in an external set of samples is ongoing.     

人肺腺癌吉非替尼耐药细胞株中微小RNA的表达谱

目的:分析人肺腺癌吉非替尼耐药细胞株PC9/AB2与亲本细胞株PC9中微小RNA(microRNA,miRNA)表达谱的差异.方法:应用Agilent human miRNA芯片分别检测PC9/AB2细胞与PC9细胞miRNA的表达谱,随后采用Agilent Feature Extraction软件分析并筛选差异表达的miRNA,应用生物信息软件预测筛选出的差异表达miRNA的潜在靶基因.应用实时荧光定量-PCR(real-time fluorogenic quantitative-PCR,RFQ-PCR)验证芯片检测结果.结果:与PC9细胞比较,PC9/AB2细胞中有36个miRNA表达上调＞2倍,有24个miRNA表达下调＞2倍.RFQ-PCR验证了芯片的结果.软件预测发现,16个miRNA有潜在靶基因,其中11个miRNA的靶基因＞100个.结论:筛选获得的差异表达miRNA可能通过调控其靶基因而参与人肺腺癌细胞对吉非替尼的耐药.     

MIR-379-5p Expression in Endometrial Cancer and Its Correlation with ROR1 Expression

Objective: To asses miR-379-5p expression in endometrial cancer (EC) and its correlation with ROR1 expression and to investigate the relation between miR-379-5p and ROR1 expressions and the clinicopathological picture of EC. Methods: Fifty female of EC were joined to this study. The gene expression of miR-379-5p (by quantitative real time-PCR) and ROR1 (by quantitative real time-PCR and immunohistochemistry) were studied in EC and normal nearby endometrial tissue. Results: The gene expression of miR-379-5p was significantly downregulated while that of ROR1 was significantly upregulated in EC tissues compared to adjacent normal endometrial tissues. Furthermore, miR-379 and ROR1 expressions significantly associated with tumor stage (P< 0.045), grade (P< 0.001), myometrial invasion (P <0.001) and LN metastasis (P< 0.034). In addition, miR-3795p and ROR1 gene expression were negatively correlated (r = -0.746, P < 0.001). Conclusions: In EC, miR-379-5p can be used as a diagnostic marker, and ROR1 could be a potential target of miR-379-5p.     

Characterization of microRNA transcriptome in lung cancer by next-generation deep sequencing

Non-small cell lung cancer (NSCLC) is the leading cause of cancer death. Systematically characterizing miRNAs in NSCLC will help develop biomarkers for its diagnosis and subclassification, and identify therapeutic targets for the treatment. We used next-generation deep sequencing to comprehensively characterize miRNA profiles in eight lung tumor tissues consisting of two major types of NSCLC, squamous cell carcinoma (SCC) and adenocarcinoma (AC). We used quantitative PCR (qPCR) to verify the findings in 40 pairs of stage I NSCLC tissues and the paired normal tissues, and 60 NSCLC tissues of different types and stages. We also investigated the function of identified miRNAs in lung tumorigenesis. Deep sequencing identified 896 known miRNAs and 14 novel miRNAs, of which, 24 miRNAs displayed dysregulation with fold change ≥4.5 in either stage I ACs or SCCs or both relative to normal tissues. qPCR validation showed that 14 of 24 miRNAs exhibited consistent changes with deep sequencing data. Seven miRNAs displayed distinctive expressions between SCC and AC, from which, a panel of four miRNAs (miRs-944, 205-3p, 135a-5p, and 577) was identified that cold differentiate SCC from AC with 93.3% sensitivity and 86.7% specificity. Manipulation of miR-944 expression in NSCLC cells affected cell growth, proliferation, and invasion by targeting a tumor suppressor, SOCS4. Evaluating miR-944 in 52 formalin-fixed paraffin-embedded SCC tissues revealed that miR-944 expression was associated with lymph node metastasis. This study presents the earliest use of deep sequencing for profiling miRNAs in lung tumor specimens. The identified miRNA signatures may provide biomarkers for early detection, subclassification, and predicting metastasis, and potential therapeutic targets of NSCLC.     

Serum miRNA Panel in Egyptian Patients with Chronic Hepatitis C Related Hepatocellular Carcinoma

Background: Primary hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. MicroRNAs (miRNAs) have great HCC diagnostic potential and circulating miRNAs have been reported as promising biomarkers for various pathologic conditions. Aim: To explore the potential benefit of serum miR-126, miR-129, miR-155, miR-203 and miR-223 as non-invasive diagnostic markers of hepatitis C virus (HCV)-related HCC. Materials and Methods: The expression of miRNA was evaluated using real-time quantitative RT-PCR in 78 serum samples (30 treatment-naive chronic HCV, 25 post-HCV compensated cirrhosis and 23 treatment- naive HCC cases). Results: Comparing miRNA fold changes in the HCC group vs the non HCC groups, there was significant fold decrease in miR-126 (P= 0.034), miR-129 (P= 0.006), miR-155 (P= 0.011), miR-203 (<0.001) and miR-223 (P= 0.013). The highest AUC to differentiate HCC patients from non-HCC was 0.76 for miR-203. Conclusions: Among studied miRNAs, serum miR-203 has the highest potential as a non-invasive biomarker of HCC.