人肝细胞肝癌和癌旁正常组织microRNA表达差异的分析

目的比较肝细胞肝癌和癌旁正常组织microRNA的表达差异,为研究肝癌的发病机理提供理论依据。方法用microRNA 微阵列芯片技术研究肝细胞肝癌细胞474种miRNAs表达谱,对比癌旁正常组织筛选差异表达miRNAs。结果获得213个差异表达（P<0.01）的miRNAs分子数据,与配对癌旁正常组织相比,其中上调表达的有116个,如miR-181,miR-21,let-7e等;下调表达的有97个,如miR-199,miR-451,miR-122等。结论miRNA可能成为肝癌的诊断工具,并对研究肝癌的致病机理提供新的理论依据。     

microRNA143表达对结肠癌组织中细胞增殖的影响及其作用机制

目的 探讨microRNA143(miR-143)表达对结肠肿瘤组织中细胞增殖和K-ras基因表达的影响.方法 采用Northern blot方法检测21例结肠癌组织和癌旁组织中miR-143的表达;构建miR-143的表达载体,将其转入人结肠癌细胞系SW480,用二苯基溴化四氮唑蓝(MTT)方法检测miR-143转染对细胞增殖的影响;通过逆转录聚合酶链反应(RT-PCR)和Western blot方法检测K-rasmRNA和蛋白的表达变化.结果 在21例结肠癌组织标本中,有17例(81.0%)癌组织的miR-143表达水平低于癌旁组织.基因转染的SW480细胞中,miR-143表达水平显著升高,细胞增殖被抑制,K-ras蛋白的表达水平下降约40.3%,而K-ras mRNA水平未受影响.结论 miR-143在结肠癌组织中的表达明显低于癌旁组织,转染细胞中高表达的miR-143能够抑制细胞增殖,下调K-ras蛋白的表达.     

miR-145通过下调OCT4基因抑制肺腺癌干细胞增殖

背景与目的 miR-145是通过miRNA芯片及qPCR验证筛选出的一种潜在肺癌"保护性"miRNA。本研究旨在探讨miR-145与肺癌干细胞之间的关系及分子机制。方法 miRNA芯片对肺腺癌患者瘤旁和正常组织进行表达谱分析;生物信息学软件预测miR-145潜在的靶基因;脂质体2000介导转染miR-145模拟物和阻遏物进入A549细胞株;实时定量PCR检测miR-145表达水平;Western blot检测OCT4蛋白水平;双荧光素酶报告基因验证miR-145是否作用于OCT4mRNA的3’UTR区预测靶位;细胞增殖实验检测miR-145对于A549细胞生长的作用;流式细胞术检测干细胞表型CD133+的表达。结果在肺腺癌组织中miR-145表达明显低于瘤旁正常组织;miRanda软件预测OCT4是miR-145潜在靶基因;与对照组相比,miR-145模拟物组和阻遏物组miR-145表达分别明显上调和下调;miR-145对A549细胞的生长有双向调节作用,过表达miR-145抑制细胞生长;过表达miR-145可明显降低OCT4蛋白水平及干细胞表型CD133百分比,而抑制miR-145表达则明显增加OCT4蛋白水平及CD133百分比。双荧光素酶报告基因检测证明miR-145可作用于OCT4mRNA的3’UTR区预测靶位。结论 miR-145可通过下调OCT4基因表达抑制A549肺腺癌细胞株中干细胞的增殖,是一种潜在的肺癌"保护性"miRNA。     

milk-145通过下调OCT4基因仰制肺腺癌干细胞增殖

背景与目的 miR-145是通过miRNA芯片及qPCR验证筛选出的一种潜在肺癌保护性miRNA。本研究旨在探讨miR-145与肺癌干细胞之间的关系及分子机制。方法 miRNA芯片对肺腺癌患者瘤旁和正常组织进行表达谱分析;生物信息学软件预测miR-145潜在的靶基因;脂质体2000介导转染miR-145模拟物和阻遏物进入A549细胞株;实时定量PCR检测miR-145表达水平;Western blot检测OCT4蛋白水平;双荧光素酶报告基因验证miR-145是否作用于OCT4mRNA的3'UTR区预测靶位;细胞增殖实验检测miR-145对于A549细胞生长的作用;流式细胞术检测干细胞表型CD133+的表达。结果在肺腺癌组织中miR-145表达明显低于瘤旁正常组织;miRanda软件预测OCT4是miR-145潜在靶基因;与对照组相比,miR-145模拟物组和阻遏物组miR-145表达分别明显上调和下调;miR-145对A549细胞的生长有双向调节作用,过表达miR-145抑制细胞生长;过表达miR-145可明显降低OCT4蛋白水平及干细胞表型CD133百分比,而抑制miR-145表达则明显增加OCT4蛋白水平...     

黄曲霉毒素B1诱导的恶性转化肝细胞miRNA表达谱的变化

目的：检测黄曲霉毒素B1（aflatoxin B1,AFB1）诱导的恶性转化肝L02细胞（L02T）的miRNA表达谱,寻找差异表达的miRNA。方法：以含有AFB1的培养液多次间歇性染毒L02细胞获得转化细胞L02T,通过miRNA芯片技术检测和分析对照L02和转化L02T细胞的miRNA表达谱;用实时荧光定量PCR方法对芯片结果加以验证;采用TargetScan软件预测miRNA可能调控的靶基因。结果：获得2组细胞856个miRNA的表达谱,在25个表达差异显著的miRNA中,15个表达上调,10个表达下调;用定量RT-PCR对芯片结果中表达差异的miR-320a、miR-638和miR-98进行验证,并对其中上调显著的miR-638进行生物信息学分析,预测到4个与肝癌相关的潜在靶基因。结论：在AFB1诱导的恶性转化肝L02细胞中筛查出25个表达差异显著的miRNA,差异表达的miRNA可能在细胞恶性转化过程中起重要作用。     

非小细胞肺癌顺铂化疗耐药相关微RNA的筛选及鉴定

 目的　探讨肿瘤细胞微RNA（miRNA）对化疗药物敏感性的作用。方法　通过miRNA芯片技术检测顺铂（DDP）耐药细胞株A549／DDP与非耐药细胞株A549的miRNA表达的差异,利用荧光定量聚合酶链反应（PCR）技术验证相应miRNA的表达情况,通过在细胞株中抑制或过表达目标miRNA,研究其对细胞化疗药物敏感性的影响。结果　A549／DDP细胞对DDP的耐药为A549细胞的18倍。A549／DDP细胞与A549细胞存在51个表达水平差异在4倍以上的miRNA,其中24个表达上调,27个表达下调。PCR进一步证实miR-376c、miR-31、miR-29a、miR-221在A549／DDP细胞中显著上调,miR-196a、miR-20a、miR-20b、miR-17、miR-451在A549／DDP细胞中显著下调。在提高A549／DDP细胞中miR-17的表达后,细胞对DDP的敏感度增加了11.7 %,提高miR-451的表达或者抑制miR-29a的表达后,对DDP的敏感度分别下降了15.5 %、12.9 %,抑制miR-376c、miR-31、miR-221或过表达miR-196a、miR-20a、miR-20b均不影响A549／DDP细胞对DDP的敏感度。结论　非小细胞肺癌DDP耐药细胞与非耐药细胞的miRNA表达谱有差异,miRNA参与肺癌化疗耐药,miR-17具有逆转非小细胞肺癌DDP耐药的潜力。     

宫颈癌及癌前病变组织中microRNAs的差异表达

目的 寻找与宫颈癌及宫颈癌前病变相关的microRNA。 方法 利用miRNA芯片,筛查宫颈 癌组织、宫颈上皮内瘤变及正常宫颈组织中差异表达的miRNA,并用实时定量RT-PCR在60份宫颈组 织标本中对4个miRNA进行验证。利用生物信息学对部分差异表达的miRNA的靶基因进行功能分析。 结果 与正常宫颈组织比较,宫颈癌及高级别宫颈病变（HSIL）中存差异表达的miRNAs,其中在宫 颈癌中下调最明显的是miR-218（下调倍数为0.175）,上调最明显的是miR-21（上调倍数为5.68）。 实时定量RT-PCR验证结果与miRNA芯片结果基本一致。功能分析显示预测的miR-218及miR-21的靶基 因与肿瘤的生长、侵袭转移有关。结论 宫颈癌及癌前病变中存在异常表达的miRNA,它们在宫颈癌 发生过程中可能起癌基因或抑癌基因的作用。     

微小RNA-181a、320a及其靶基因TGF-β1在食管鳞癌中的表达

目的：检测人食管鳞癌组织中miR-181a、320a及TGF-β1的表达情况,研究其在食管鳞癌发生中的作用。方法：收集食管鳞癌及癌旁正常组织各3例,抽取总RNA,利用miRNA芯片技术检测miRNA的表达;采用实时定量反转录一聚合酶链反应(qRT-PCR)方法验证miRNA芯片结果的可靠性。采用软件和数据库对差异表达miRNA调控的靶基因进行初步分析。收集食管鳞癌及对照正常组织各22例,采用实时定量反转录-聚合酶链反应(qRT-PCR)方法检测miR-181a、320a和TGF-β1mRNA。结果：miRNA芯片结果显示,共有22种miRNA在食管鳞癌中差异表达（p<0.05）,其中6种显著上调,16种显著下调;qRT-PCR证实miR-320a表达下降,miR-181a表达上升,差异均有统计学意义（P﹤0.05）,与芯片结果一致; TGF-β1mRNA在食管鳞癌中表达较对照正常组织稍升高,但差异无显著性。结论：miR-181a、miR-320a可能参与食管鳞癌的发生发展过程。     

哈萨克族食管癌组织中miR-143、miR-145和Survivin mRNA的表达及其临床病理意义

目的:检测新疆哈萨克族食管癌组织中miR-143、miR-145和Survivin mRNA的表达,探讨其在哈萨克族食管癌发生发展中的作用及临床意义。方法:采用实时荧光定量PCR方法检测47例哈萨克族食管癌及癌旁组织标本中miR-143、miR-145和Survivin mRNA的表达水平,分析它们与临床病理指标的关系。结果:miR-143、miR-145在哈萨克族食管癌组织中表达较癌旁组织降低(P均<0.01);Survivin mRNA在哈萨克族食管癌组织中表达较癌旁组织升高(P=0.000);miR-143的表达与肿瘤分化程度、淋巴结转移、临床分期相关(P=0.018、0.004、0.022);miR-145的表达与分化程度、淋巴结转移相关(P=0.007、0.039);Survivin mRNA的表达与淋巴结转移及临床分期相关(P=0.042、0.034)。miR-143的表达与miR-145呈正相关(r=0.662,P=0.000),与Survivin mRNA呈负相关(r=-0.313,P=0.002);结论:在哈萨克族食管癌中miR-143、miR-145低表达、Survivin mRNA高表达,miR-143/145基因簇、Survivin mRNA可能共同参与哈萨克族食管癌发生发展过程。     

Identification of aberrantly expressed miRNAs in rectal cancer

Disturbance of miRNA expression may play a key role in the initiation and progression of colorectal cancer (CRC). CRC should be viewed as a heterogeneous disease, but previous studies have only screened dysregulated miRNAs in CRC from a panel of 96, 145, 287 and 455 miRNAs, respectively. It is necessary to identify new aberrantly expressed miRNAs in rectal cancer. In this study tissue samples were derived from patients undergoing a surgical procedure to remove a portion of cancers. The expression profile of 904 miRNAs was analyzed using a miRCURY? LNA Array from 6-paired rectal cancers and normal tissues. The expression levels of 4 miRNAs were compared by real-time PCR between colon and rectal cancer, and also the expression levels of metastatic miRNAs in different stages of rectal cancer were analyzed. We found that 67 miRNA precursors are upregulated in rectal cancer (p<0.05) and 21 of those have never been reported in colorectal cancer (CRC); 39 miRNA precursors are downregulated (p<0.05) and 24 novel dysregulated miRNAs were identified in rectal cancer. miR-31, miR-126 and miR-143 are differentially expressed between colon cancer and rectal cancer. Here, we report an miRNA profile of rectal cancer, and we identified differential expression patterns of miRNAs between rectal and colon cancers. This novel information may suggest the potential roles of these miRNAs in the diagnosis of rectal cancer.     

Down Regulated Expression Levels of miR-27b and miR-451a as a Potential Biomarker for Triple Negative Breast Cancer Patients Undergoing TAC Chemotherapy

Background: Triple negative breast cancer (TNBC) is associated with poor prognosis, aggressive phenotype(s) of tumours, partial chemotherapy response, and lack of clinically proven therapies. MicroRNAs (miRNAs) can target and modulate key genes that are involved in TNBC chemotherapy. Deregulated miRNA expression is highly involved in anti-cancer drug resistance phenotype and thus, miRNAs tend to be promising candidates for prediction of chemotherapy response and recurrence. Aim: This study aimed to investigate the expression levels of selected miRNAs (miR-21, miR-27b, miR-34a, miR-182, miR-200c and miR-451a) in cancerous and normal adjacent tissues of TNBC patients and to correlate with the clinicopathological data. Methods: Forty-one (41) FFPE tissue block of histopathologically confirmed TNBC patients was collected. Total RNA from the cancerous and adjacent non-cancerous tissues were isolated, transcribed, and pre-amplified. The relative expression level of miRNAs in tumour and normal adjacent tissues of TNBC patients was analysed using qRT-PCR. Results: Out of six miRNAs studied, the relative expression of miR-27b and miR-451a were found to be significantly lower in cancerous as compared to normal adjacent tissues of TNBC patients. In addition, a significant down regulation of miR-451a was also observed in infiltrating ductal carcinoma subtype, stages I and II, in both grade II and III, premenopausal and postmenopausal as well as in those with positive axillary lymph node metastases. Conclusion: The results suggest the possible utilization of miR-27b and miR-451a expression levels as potential predictive risk markers for TNBC patients undergoing TAC chemotherapy.     

microRNA Expression Profile in Patients with Stage II Colorectal Cancer: A Turkish Referral Center Study

Background: There are increasing data about microRNAs (miRNA) in the literature, providing abundantevidence that they play important roles in pathogenesis and development of colorectal cancer. In this study, weaimed to investigate the miRNA expression profiles in surgically resected specimens of patients with recurrentand non-recurrent colorectal cancer. Materials and Methods: The study population included 40 patients withstage II colorectal cancer (20 patients with recurrent tumors, and 20 sex and age matched patients withoutrecurrence), who underwent curative colectomy between 2004 and 2011 without adjuvant therapy. Expression of16 miRNAs (miRNA-9, 21, 30d, 31, 106a, 127, 133a, 133b, 135b, 143, 145, 155, 182, 200a, 200c, 362) was verifiedby quantitative real-time polymerase chain reaction (qRT-PCR) in all resected colon cancer tissue samples andin corresponding normal colonic tissues. Data analyses were carried out using SPSS 15 software. Values werestatistically significantly changed in 40 cancer tissues when compared to the corresponding 40 normal colonictissues (p<0.001). MiR-30d, miR-133a, miR-143, miR-145 and miR-362 expression was statistically significantlydownregulated in 40 resected colorectal cancer tissue samples (p<0.001). When we compared subgroups,miRNA expression profiles of 20 recurrent cancer tissues were similar to all 40 cancer tissues. However in 20non-recurrent cancer tissues, miR-133a expression was not significantly downregulated, moreover miR-133bexpression was significantly upregulated (p<0.05). Conclusions: Our study revealed dysregulation of expressionof ten miRNAs in Turkish colon cancer patients. These miRNAs may be used as potential biomarkers for earlydetection, screening and surveillance of colorectal cancer, with functional effects on tumor cell behavior.     

MicroRNA expression signature in gastric cancer

Objective: To identify the miRNA specific signature as novel diagnostic and prognostic tools for gastric cancer. Methods: miRNAs expression profiling of 3 normal gastric tissues, 24 malignant tissues, gastric cancer cell SGC7901 and normal gastric cell GES-1 were detected using microarray technology. The hierarchical clustering algorithm of the Cluster software was used to analyse the miRNAs expression of all samples. The expression levels of miR-433 and miR-9 which were significantly down-regulated in gastric cancer tissues and SGC7901 cells by microarray technology were validated by quantitative Real-time PCR (qRT-PCR).Results: Differential expressions of 26 individual miRNAs between normal samples (including 3 normal gastric tissues and GES-1 cells) and carcinomas (including 24 malignant tissues and SGC7901 cells) were discovered,19 of them showing down-regulation and 7 up-regulation in carcinoma samples. Hierarchical clustering of the cancer samples by their miRNA expression accurately separated the carcinomas from normal samples and further their histotypes of carcinomas. The expression levels of miR-433 and miR-9 were significantly down-regulated in gastric cancer tissues and SGC7901cells Conclusion: The differential expression of miR-433 and miR-9 may be used as a novel diagnostic tool for gastric cancer.     

miRNA-451通过MRP靶向调控胃癌细胞对5-Fu耐药性的机制研究

目的 探讨miR-451通过下调耐药基因MRP表达，调控胃癌对5-Fu耐药的相关机制。方法 采用实时荧光定量PCR检测20对人胃癌组织及癌旁组织和胃癌细胞系中miR-451的相对表达量，根据患者对药物的反应进行分组并检测耐药组以及非耐药组miR-451的表达水平。构建plent-miR-451稳定过表达胃癌细胞系，通过荧光实时定量PCR检测胃癌细胞系miR-451过表达效率，CCK8法检测不同浓度5-Fu对细胞增殖活力的影响。生物信息学方法分析miR-451的靶基因，并通过荧光素酶实验验证。实时定量PCR以及Western blot检测miR-451对靶基因MRP mRNA和蛋白水平的影响。结果 miR-451在正常组织中表达量高于胃癌组织，在非耐药胃癌组织中高于耐药胃癌组织。过表达miR-451降低了胃癌细胞对5-Fu的耐受能力（P=0.0006）。生物信息学分析显示MRP为miR-451的靶基因，荧光素酶实验同时也证实MRP为miR-451的潜在靶基因。过表达miR-451可导致耐药基因MRP mRNA以及蛋白水平均显著降低（P=0.00069）。结论 过表达miR-451可下调耐药基因MRP表达，使肿瘤细胞对5-Fu耐药性降低。     

miR-93-5p和miR-27a-3p在直肠癌组织中的表达及其意义

目的 探讨在直肠癌组织中呈现出特异性表达的miRNA与临床病理分期、肿瘤浸润深度、淋巴结转移等参数之间的关系及其可能的意义。方法 用微阵列基因芯片技术分析未经任何术前放化疗的71例直肠癌患者癌组织与癌旁组织间miRNA表达的区别,筛选出上调的miR-93-5p和下调的miR-27a-3p,扩大样本量后进行qRT-PCR验证,随后进行多种临床病理参数分析并探讨其可能存在的意义。结果 miR-27a-3p的表达在芯片检测中呈现出低表达,但在PCR验证时呈现出了高表达,且数据较为离散;miR-93-5p在两种检测方法中均显示出高表达的特性(癌组织表达量是癌旁组织的3.165倍,P=0.006),并与肿瘤体积(P=0.004)、治疗前癌胚抗原水平(P=0.001)及淋巴结转移数目(r=0.534,P=0.005)具有相关性,其中与治疗前癌胚抗原水平及淋巴结转移阳性组受侵数目存在正相关。结论 在直肠癌组织中存在特异性表达的miRNA。根据miR-93-5p和miR-27a-3p在直肠癌组织中的表达特点,miR-93-5p有望作为新型生物标记物,为直肠癌的临床诊疗提供参考价值。     

Down Regulation of miR-34a and miR-143 May Indirectly Inhibit p53 in Oral Squamous Cell Carcinoma: a Pilot Study

Background: Aberrant microRNA expression has been associated with the pathogenesis of a variety of human malignancies including oral squamous cell carcinoma (SCC). In this study, we examined primary oral SCCs for the expression of 6 candidate miRNAs, of which five (miR-34a, miR-143, miR-373, miR-380-5p, and miR- 504) regulate the tumor suppressor TP53 and one (miR-99a) is involved in AKT/mTOR signaling. Materials and Methods: Tumor tissues (punch biopsies) were collected from 52 oral cancer patients and as a control, 8 independent adjacent normal tissue samples were also obtained. After RNA isolation, we assessed the mature miRNA levels of the 6 selected candidates against RNU44 and RNU48 as endogenous controls, using specific TaqMan miRNA assays. Results: miR-34a, miR-99a, miR-143 and miR-380-5p were significantly down-regulated in tumors compared to controls. Moreover, high levels of miR-34a were associated with alcohol consumption while those of miR-99a and miR-143 were associated with advanced tumor size. No significant difference was observed in the levels of miR-504 between the tumors and controls whereas miR-373 was below the detection level in all but two tumor samples. Conclusions: Low levels of miR-380-5p and miR-504 that directly target the 3’UTR of TP53 suggest that p53 may not be repressed by these two miRNAs in OSCC. On the other hand, low levels of miR-34a or miR-143 may relieve MDM4 and SIRT1 or MDM2 respectively, which will sequester p53 indicating an indirect mode of p53 suppression in oral tumors.     

Identification of new aberrantly expressed miRNAs in intestinal-type gastric cancer and its clinical significance

miRNAs are small 19 to 22 nucleotide sequences of RNA that negatively regulate gene expression. miRNA expression profiles may become useful biomarkers for diagnostics, prognosis and prediction of response to treat, and it could be a powerful tool for cancer prevention and therapeutics. Several miRNA expression profiles of miRNAs in gastric cancer have been reported, but these studies screened only few miRNAs and samples used in experiments include several different subtypes of gastric cancers, which decrease the sensitivity to identify new aberrant miRNAs. In this study, a miRNA expression profile was identified by miRCURY LNA Array (v.14.0) between intestinal-type gastric cancers and normal tissues. Forty miRNA precursors were up-regulated and thirty-six miRNA were down-regulated in intestinal-type gastric cancers (p<0.01). Sixteen new miRNAs were found in intestinal-type gastric cancers. Seventeen new miRNAs were found in intestinal-type gastric cancers. miR-145, miR-27a, miR-494 are differently expressed between intestinal-type and diffuse-type gastric cancers. miR-32, miR-182 and miR-143 dysregulated expression levels are related with different pathological stages of intestinal-type gastric cancers (p<0.01). Taken together, aberrantly expressed miRNAs may offer new clues to tumorigenesis of gastric cancers. miR-32, miR-182 and miR-143 may be potential diagnostic biomarkers for intestinal-type gastric cancers.