miR-190的表达下调有利于抑制结直肠癌

研究miR-190在结直肠癌(colorectal cancer,CC)患者中的表达和作用机制。采用Real-time PCR和探针原位杂交的方法检测miR-190在结直肠癌患者的癌组织和癌旁正常组织中的表达量变化。利用Targetscan数据库,寻找潜在的miR-190靶基因,并采用双荧光素酶报告基因验证。结果发现,相比于癌旁正常组织,miR-190在结直肠癌患者的癌组织中表达量显著下降(p0.000 1)。通过Targetscan数据库找到miR-190可作用于细胞因子IGF-1,双荧光素酶报告基因实验也证实了miR-190可以作用于IGF-1的3'UTR区域,从而抑制IGF-1的表达。在结直肠癌的发病过程中,miR-190表达量下降,导致IGF-1含量上升,进而促进了结肠癌的发展,miR-190具有抑癌作用。     

家蚕miR-301对化学感受蛋白基因csp9表达的调控

【目的】探索家蚕Bombyx mori miRNAs对化学感受蛋白基因表达的调控作用,以进一步研究miRNAs及其靶基因在昆虫化学识别中的作用。【方法】利用生物信息学方法预测和筛选可能作用于家蚕化学感受蛋白CSPs基因家族成员的miRNAs;实时荧光定量PCR分析预测获得的候选miR-301和其作用的靶基因在家蚕成虫不同组织中的表达变化;构建miR-301预测靶基因3′-UTR的双荧光素酶报告载体,与合成的miR-301 mimics或阴性对照转染人胚肾细胞HEK293,通过双荧光素酶报告基因检测系统中荧光素酶活性变化检测miR-301对其靶基因表达的调控作用。【结果】生物信息学分析结果发现,家蚕化学感受蛋白基因csp9是miR-301的预测靶基因,二者的结合位点位于csp9的3′-UTR区。实时荧光定量PCR检测结果表明,miR-301在交配后家蚕雌雄成虫触角和雄成虫头部都显著上调表达,靶基因csp9在对应组织中表达则显著下调。二者共转染HEK293细胞后,双荧光素酶检测结果表明,miR-301可以通过与csp9 3′-UTR的互作,显著抑制上游荧光素酶报告基因的表达。【结论】家蚕化学感受蛋白基因csp9是miR-301的靶基因,miR-301通过与靶基因3′-UTR的结合,在翻译水平上抑制csp9的表达。     

环状RNA circTCF25通过miR-103a-3p/miR-107调控CDK6的表达促进膀胱癌的增殖和迁移

该文旨在探讨环状RNA circTCF25对膀胱癌增殖和迁移的影响。采用RT-q PCR检测膀胱癌及癌旁组织中miR-103a-3p和miR-107的表达水平;采用Western blot和免疫组化检测膀胱癌细胞及膀胱癌和癌旁组织中CDK6的蛋白表达;将circTCF25过表达载体转染两种膀胱癌细胞后,采用RT-q PCR检测细胞中circTCF25以及miR-103a-3p和miR-107的表达水平;采用双荧光素酶报告基因实验验证circTCF25靶向结合miR-107及miR-107的靶基因CDK6;划痕实验检测细胞迁移能力;Edu实验检测细胞增殖能力。RT-q PCR结果表明,膀胱癌组织中miR-103a-3p和miR-107的表达明显低于癌旁组织。免疫组化和Western blot结果显示,膀胱癌组织中CDK6蛋白质水平明显高于癌旁组织。转染circTCF25过表达载体的细胞中,circTCF25的表达水平高于对照组。过表达circTCF25后,细胞中miR-103a-3p和miR-107的表达显著下降,CDK6的蛋白水平增加。双荧光素酶报告基因实验表明,circTCF25可以直接结合miR-107并降低其对靶基因CDK6的抑制。过表达circTCF25后,细胞迁移和增殖能力增强。该研究说明,环状RNA circTCF25可通过miR-103a-3p/miR-107调控CDK6的表达促进膀胱癌的增殖和迁移。     

MiR-30e调控心肌肥厚的作用机制研究

目的:预测并鉴定miR-30e的靶基因,阐明miR-30e调控心肌肥厚的分子机制.方法:分离新生大鼠心肌细胞,用苯肾上腺素(PE)处理心肌细胞构建心肌细胞肥大模型,48小时后通过定量PCR方法检测miR-30e的表达水平变化.利用生物信息学方法预测miR-30e的靶基因,并通过荧光素酶报告基因实验和蛋白免疫印迹方法验证miR-30e的靶基因.结果:与对照组相比,PE处理48hr后,心肌肥厚标志基因nppa表达明显升高,肥大心肌细胞中miR-30e明显下调.生物信息学预测细胞骨架调控蛋白Twinfilin-1(Twf1)3'UTR有两个miR-30e的结合位点.过表达miR-30e能抑制含有Twf1 3'UTR的荧光素酶报告基因的表达,降低Twf1的蛋白表达水平.结论:Twf1为miR-30e的靶基因,miR-30e通过抑制Twf1的表达调控心肌肥厚.     

胶质瘤细胞中miR-223对PAX6基因3'非翻译区的调控作用

目的:明确miR-223在胶质瘤细胞中对PAX6基因3'-UTR的靶向调控作用。方法:生物信息学软件预测PAX6基因3'-UTR的靶向miRNAs;分别构建野生型和突变型PAX6基因3'-UTR双荧光素酶报告基因质粒;共转染miR-223 mimics与野生型和突变型双荧光素酶报告基因质粒于U251细胞中,双荧光素酶检测系统测定荧光素酶活性。结果:生物信息学软件预测显示PAX6可能是miR-223的靶基因;与转染野生型PAX6 3'-UTRpsiCHECKTM-2质粒组和转染突变型PAX6 Mut 3'-UTR-psiCHECKTM-2质粒组相比,miR-223 mimics能明显降低野生型荧光素酶质粒活性。结论:miR-223能够靶向负性调控PAX6基因3'-UTR的活性。     

miR-598 对结直肠癌细胞转移潜能的影响

目的:探讨miR-598在结直肠癌转移中的作用和分子机制,为寻找新的结直肠癌治疗靶标提供理论依据。方法:收集30对人结直肠癌及癌旁正常组织标本,采用qRT-PCR检测miR-598的表达,采用Transwell和划痕实验确定miR-598对结直肠癌细胞侵袭和迁移能力的影响,利用在线靶基因预测软件,筛选出miR-598可能的下游靶基因Jagged 1(JAG1),利用Western blot及双荧光素酶报告基因实验检测miR-598对JAG1及上皮间质转化标志物(Vimentin及E-cadherin)表达的影响。结果:与正常肠黏膜组织对比,miR-598在结直肠癌组织中的表达水平明显降低;miR-598显著抑制结直肠癌细胞的侵袭及迁移能力;分子机制分析证实miR-598能够作用于JAG1的3'-UTR并抑制其表达;过表达miR-598显著下调Vimentin的表达水平,而提高E-cadherin的表达水平。结论:miR-598在人结直肠癌中表达明显下调;miR-598通过靶向调控靶基因JAG1的表达,抑制结直肠癌细胞EMT,从而有效的抑制了结直肠癌细胞的侵袭和迁移。     

MicroRNA-146a抑制胶质瘤细胞增殖的研究

目的：检测胶质瘤中miR-146a的表达水平,并研究miR-146a对胶质瘤细胞增殖的影响。方法：应用实时定量PCR的方法检测胶质瘤组织和癌旁组织中miR-146a的表达水平,采用脂质体细胞转染miRNA模拟物的方式过表达miR-146a,MTT法检测转染后细胞的增殖率,利用在线软件targetScan预测miRNA可能的靶基因。结果：miR-146a在胶质瘤组织中表达明显降低（P〈0.01）,相对表达水平为癌旁组织的35%,细胞转染miR-146a模拟物后,miR-146a表达明显增加,癌细胞增殖率明显降低（P〈0.01）,仅为原细胞的47%。Notch1基因是miR-146a影响胶质瘤细胞增殖活力的可能靶基因。结论：miR-146a可能通过抑制Notch1基因的表达调控胶质瘤细胞的增殖。     

微小分子miR-125b新靶基因的鉴定及其功能初步研究

目的:利用生物信息学方法预测miR-125b的新靶基因,在肝癌细胞系中进行验证和结合位点的鉴定,为阐明miR-125b在肝癌发生发展中的作用和机制提供新线索。方法:Western印迹分析在肝癌细胞中过表达miR-125b后上皮-间充质转化(EMT)相关蛋白的表达情况;对肝癌患者肿瘤组织及癌旁组织的miR-125b表达差异进行实时定量PCR检测,同时对SNAIL1的表达情况进行免疫组化检测;用生物信息学方法预测miR-125b的新靶基因;利用双萤光素酶报告系统验证miR-125b在预测的新靶基因mRNA的3'非翻译区是否有直接结合位点;构建新靶基因的真核过表达载体,检测新靶基因过表达后对miR-125b表达水平的影响。结果:在肝癌细胞中过表达miR-125b可抑制细胞EMT过程,下调α平滑肌肌动蛋白、神经钙黏素的表达;miR-125b在肝癌患者肿瘤组织中的表达远低于癌旁组织,而SNAIL1作为调控EMT的主要转录因子之一,其在肿瘤组织中的入核比例明显高于癌旁组织;用TargetScan预测到snail1是miR-125b的潜在靶点之一,但双萤光素酶实验表明snail1并非miR-125b的直接靶基因。此外,我们意外发现在肝癌细胞中过表达SNAIL1可上调miR-125b的表达。结论:miR-125b可抑制肝癌EMT过程,但并非直接通过靶向snail1发挥作用,两者在肝癌细胞中存在着复杂的间接调控关系。     

miR-143在人颈动脉粥样硬化患者斑块组织中表达变化及作用机制

目的探讨miR-143在人颈动脉粥样硬化患者斑块组织中的表达变化及可能的作用机制。方法收集我院血管外科因颈动脉狭窄行颈动脉内膜剥脱术(CEA)切除的颈动脉斑块组织及斑块旁内膜组织56例,根据术前颈动脉超声检查及术后斑块病理学检查将所取得的斑块组织又分为稳定斑块组26例和不稳定斑块组30例。另外选择同期年龄、性别相匹配的在我院因外伤、门脉高压或原发性血小板增多症而行脾脏切除术患者的正常的脾动脉内膜组织20例作为正常对照组,通过实时荧光定量PCR(qRT-PCR)检测组织中miR-143的表达水平。体外培养人主动脉血管平滑肌细胞(HAVSMCs),分别转染mi R-143模拟物、模拟物阴性对照、miR-143抑制物、抑制物阴性对照,采用qRT-PCR检测转染后HAVSMC细胞miR-143表达水平的变化,CCK-8法和Transwell迁移实验分别检测转染后细胞增殖活性和迁移能力的变化。通过生物信息学预测miR-143的可能靶基因,双荧光素酶报告基因实验观察miR-143与ADAMTS4的靶向调控关系,Western blot观察miR-143对ADAMTS4表达水平的影响。结果颈动脉粥样硬化斑块组织中miR-143表达水平明显低于斑块旁内膜组织和正常动脉血管内膜组织,并且不稳定斑块组患者斑块组织中miR-143的表达水平明显低于稳定斑块组斑块组织。转染miR-143模拟物后,HAVSMCs中miR-143表达水平明显升高,增殖活性和迁移能力明显降低;转染miR-143抑制物后,HAVSMCs中miR-143表达水平明显降低,增殖活性和迁移能力明显升高。双荧光素酶报告基因显示ADAMTS4是miR-143的直接靶基因,Western blot显示miR-143能够在转录后水平负向调控ADAMTS4表达。结论 miR-143在颈动脉粥样硬化斑块组织中表达降低,其可能通过靶向调控ADAMTS4影响血管平滑肌细胞增殖和迁移能力,与颈动脉斑块的形成和不稳定性有关。     

miR-217参与高糖诱导的内皮细胞凋亡的调控

目的:研究miR-217对高糖诱导的内皮刺激内皮细胞凋亡的作用。方法:培养人冠状动脉内皮细胞,用含D-葡萄糖(30mmol/L)的培养液刺激:(1)利用实时定量PCR检测内皮细胞相关微小RNA(miR-217、miR-137、miR-29c、miR-218、miR-451、miR-328、miR-517c和miR-216a等)的表达变化;(2)利用慢病毒感染技术干预内皮细胞miR-217水平,利用流式细胞术检测细胞凋亡水平;(3)生物信息学预测、双荧光素酶报告基因验证以及蛋白免疫印迹法(western blot)确定miR-217的靶基因。结果:(1)实时定量PCR检测发现高糖刺激内皮细胞后,miR-217、miR-137、miR-29c、miR-218等的表达上调(P0.01),miR-451、miR-328、miR-517c和miR-216a的表达下调(P0.01),其中miR-217比对照细胞升高了5.67倍;(2)慢病毒感染内皮细胞后再经高糖刺激,流式细胞术检测发现过表达miR-217的内皮细胞凋亡水平有显著提高;(3)生物信息学分析发现SIRT1基因的3'非翻译区上存在一个miR-217的结合位点,双荧光素酶报告基因和western blot结果均证明SIRT1是miR-217的靶基因。结论:miR-217可能通过抑制SIRT1的表达参与高糖诱导的内皮细胞凋亡的调控。     

Overexpression of miR-493-3p suppresses ovarian cancer cell proliferation,migration and invasion through downregulating DPY30

Accumulating evidence has verified that the aberrant expression level of miR-493?3p is often associated with the occurrence of numerous cancers. Nevertheless, the expression level and effect of this microRNA in ovarian cancer (OC) remain largely unclear. Therefore, the molecular function of miR-493?3p in OC progression was systematically investigated in this study.The expression of miR-493?3p and DPY30 was assessed by qRT-PCR. The protein expression level of DPY30 in cell lines was further assessed by western blot. Cell viability was respectively examined in vitro functional experiments including CCK-8 assay, EdU assay, wound healing assay, colony formation and apoptosis assays as well as the scratch test and transwell assay. Bioinformatics analysis and luciferase reporter assays were performed to predict and clarity of the correlation between miR-493?3p and DPY30.The expression of miR-493?3p was significantly reduced in OC tissues and cells. Functional experimental results showed that miR-493?3p suppressed cellular proliferation, migration, invasion, but promoted apoptosis in OC cells. Mechanistically, we also confirmed that DPY30 could be directly targeted by miR-493?3p based on bioinformatics and dual-luciferase reporter analysis. Rescue experiments results indicated that the inhibitory effect of miR-493?3p on cellular proliferation, migration and invasion and the promotive effect of miR-493?3p on apoptosis was abolished by DPY30 overexpression.Our findings demonstrated the antitumor effect of miR-493?3p through targeting DPY30 in ovarian cancer, indicating that miR-493?3p might represent a promising target for ovarian cancer diagnosis and treatment.     

Low Expression of miR-196b Enhances the Expression of BCR-ABL1 and HOXA9 Oncogenes in Chronic Myeloid Leukemogenesis

MicroRNAs (miRNAs) can function as tumor suppressors or oncogene promoters during tumor development. In this study, low levels of expression of miR-196b were detected in patients with chronic myeloid leukemia. Bisulfite genomic sequencing PCR and methylation-specific PCR were used to examine the methylation status of the CpG islands in the miR-196b promoter in K562 cells, patients with leukemia and healthy individuals. The CpG islands showed more methylation in patients with chronic myeloid leukemia compared with healthy individuals (P<0.05), which indicated that low expression of miR-196b may be associated with an increase in the methylation of CpG islands. The dual-luciferase reporter assay system demonstrated that BCR-ABL1 and HOXA9 are the target genes of miR-196b, which was consistent with predictions from bioinformatics software analyses. Further examination of cell function indicated that miR-196b acts to reduce BCR-ABL1 and HOXA9 protein levels, decrease cell proliferation rate and retard the cell cycle. A low level of expression of miR-196b can cause up-regulation of BCR-ABL1 and HOXA9 expression, which leads to the development of chronic myeloid leukemia. MiR-196b may represent an effective target for chronic myeloid leukemia therapy.     

MiR-1827 functions as a tumor suppressor in lung adenocarcinoma by targeting MYC and FAM83F

The bioactivity of microRNA-1827 (miR-1827) in lung adenocarcinoma cells would be explored. The expression level of gene and miR-1827 in 76 pairs of lung adenocarcinoma tissues and adjacent counterparts were analyzed by a quantitative real-time polymerase chain reaction. Primary lung adenocarcinoma cells were derived from patients’ tissues. These cells were treated with miR-1827 agomir to mimic the upregulation of endogenous miR-1827. The malignant degree of lung adenocarcinoma cells in vitro was evaluated by cell proliferation, colony formation, transwell invasion, and apoptosis assays. Western blot analysis was used to observe the transition of lung adenocarcinoma cells from epithelial-to-mesenchymal. Target genes of miR-1827 were predicted by bioinformatics analysis. In addition, the interaction between miR-1827 and candidate messenger RNAs was verified by dual-luciferase reporter assay and AGO2-RNA immunoprecipitation. Besides, the effect of miR-1827 on tumors was verified by in vivo experiments. Transient gene overexpression was achieved by plasmids transfection. In this study, we found that the expression of miR-1827 was downregulated in lung adenocarcinoma, and its low expression was significantly correlated with the progression of lung adenocarcinoma and poor prognosis of patients. miR-1827 overexpression remarkably reduced the malignancy of primary lung adenocarcinoma cells in vitro. MYC and FAM83F were identified as two targeted genes of miR-1827 in lung adenocarcinoma cells. The levels of these two genes were upregulated in lung adenocarcinoma, and their high expression was significantly associated with the progression of lung adenocarcinoma and poor prognosis of patients. Overexpression of MYC or FAM83F attenuated the effects of miR-1827 on primary lung adenocarcinoma cells in vitro. In addition, in vivo experiments showed that miR-1827 inhibited tumor growth by reducing the levels of MYC and FAM83F. In conclusion, miR-1827 might repress the development of lung adenocarcinoma by targeting oncogenic genes MYC and FAM83F.     

miR-450a-5p在浆液性卵巢癌中的表达及临床意义

目的:检测miR-450a-5p在浆液性卵巢癌中的表达情况,并分析miR-450a-5p的表达与浆液性卵巢癌临床病理特征之间的关系,探讨其在浆液性卵巢癌发生、发展中的意义。方法:采用实时荧光定量PCR技术,检测101例浆液性卵巢癌组织及对照50例正常输卵管伞端组织中miR-450a-5p的表达情况,并分析miR-450a-5p表达水平与临床病理特征之间的关系。实验数据采用统计学软件进行分析。结果:miR-450a-5p在浆液性卵巢癌组织中的表达量显著低于正常输卵管组织对照组(P0.01)。miR-450a-5p的表达水平与浆液性卵巢癌临床病理特征之间差异均无统计学意义(P0.05)。结论:miR-450a-5p可能作为抑癌基因,在卵巢癌的发生、发展中发挥重要作用,进一步的研究有望为浆液性卵巢癌的早期诊断及个体化治疗提供新的理论依据。     

miR-101 is down-regulated by the hepatitis B virus x protein and induces aberrant DNA methylation by targeting DNA methyltransferase 3A

The hepatitis B virus x (HBx) protein has been implicated in HBV-related hepatocellular carcinoma (HCC) pathogenesis. However, whether HBx regulates miRNA expression that plays important roles in gene regulation during hepatocarcinogenesis remains unknown. The expression of microRNA-101 (miR-101) in HBV-related HCC tissues and HCC cells was evaluated by real-time PCR. The direct target of miR-101, DNA methyltransferase 3A (DNMT3A), was identified in silico and validated using a 3′-UTR reporter assay. miR-101 was functionally characterized in cells with transiently altered miR-101 expression. HBx expression was found to have a significant inverse correlation with miR-101 expression in HBx-expressing HepG2 compared to control HepG2 cells. miR-101 expression was frequently down-regulated in HBV-related HCC tissues compared to adjacent noncancerous hepatic tissues and had a significant inverse correlation with DNMT3A expression in HBV-related HCCs. Further characterization of miR-101 revealed that it negatively regulated DNA methylation partly through targeting DNMT3A. HBx-mediated miR-101 down-regulation and DNMT3A up-regulation supported the enhanced DNA methylation of several tumor-suppressor genes in HBx-expressing cells. Our studies demonstrating the deregulation of miR-101 expression by HBx may provide novel mechanistic insights into HBV-mediated hepatocarcinogenesis and identify a potential miRNA-based targeted approach for treating HBV-related HCC.     

miR-188-5p对肾间质纤维化过程中MMP-13表达的影响

目的:探讨miR-188-5p对肾间质纤维化过程中基质金属蛋白酶(matrixmetalloproteinases,MMPs)表达的影响。方法:采用TGF-β1诱导肾小球系膜细胞(Mesangial cells,MC)纤维化,观察纤维化过程中miR-188-5p和MMP-13的表达变化;通过报告基因实验研究miR-188-5p对MMP-13的调控作用;通过脂质体转染的方法将人工合成的miR-188-5p mimics/inhibitor转入细胞内增加或减少miR-188-5p的表达,进一步观察miR-188-5p对MMP-13表达的影响。结果:TGF-β1诱导肾小球系膜细胞纤维化后miR-188-5p的表达明显升高,而MMP-13表达下调;报告基因实验表明miR-188-5p对MMP-13的表达有明显的调控作用,减少miR-188-5p的表达后MMP-13的表达上调,而增加miR-188-5p的表达后MMP-13的表达下调,呈明显负性调控。结论:在肾间质纤维化过程中,miR-188-5p可能通过抑制MMP-13的表达而发挥促纤维化的作用,本研究为肾间质纤维化的治疗提供了新的靶点。     

MiR-9-3p regulates the biological functions and drug resistance of gemcitabine-treated breast cancer cells and affects tumor growth through targeting MTDH

This study explored the role of MTDH in regulating the sensitivity of breast cancer cell lines to gemcitabine (Gem) and the potential miRNAs targeting MTDH. The expression of MTDH in cancer tissues and cells was detected by immunohistochemical staining or qRT-PCR. The target genes for MTDH were predicted by bioinformatics and further confirmed by dual-luciferase reporter assay and qRT-PCR. Cancer cells were transfected with siMTDH, MTDH, miR-9-3p inhibitor, or mimics and treated by Gem, then CCK-8, colony formation assay, tube formation assay, flow cytometry, wound healing assay, and Transwell were performed to explore the effects of MTDH, miR-9-3p, and Gem on cancer cell growth, apoptosis, migration, and invasion. Expressions of VEGF, p53, cleaved caspase-3, MMP-2, MMP-9, E-Cadherin, N-Cadherin, and Vimentin were determined by Western blot. MTDH was high-expressed in cancer tissues and cells, and the cells with high-expressed MTDH were less sensitive to Gem, while silencing MTDH expression significantly promoted the effect of Gem on inducing apoptosis, inhibiting cell migration, invasion, and growth, and on regulating protein expressions of cancer cells. Moreover, miR-9-3p had a targeted binding relationship with MTDH, and overexpressed miR-9-3p greatly promoted the toxic effects of Gem on cancer cells and expressions of apoptosis-related proteins, whereas overexpressed MTDH partially reversed such effects of overexpressed miR-9-3p. The study proved that miR-9-3p regulates biological functions, drug resistance, and the growth of Gem-treated breast cancer cells through targeting MTDH.Subject terms: Cancer, Cell biology