circ＿0015756通过调控miR-515-5p/HMGB3轴影响肺癌细胞增殖、凋亡和迁移

为探讨环状RNA 0015756(circ_0015756)对肺癌细胞增殖、凋亡和迁移的影响和潜在机制,该研究采用实时定量PCR(RT-qPCR)分析肺癌组织和癌旁组织中circ_0015756和微小RNA(miR)-515-5p的表达水平。同时,将circ_0015756小干扰RNA(si-circ_0015756)、miR-515-5p模拟物、si-circ_0015756+miR-515-5p抑制物分别转染肺癌细胞A549,采用四甲基偶氮唑蓝实验、平板克隆实验检测A549细胞的增殖能力,采用流式细胞术分析A549细胞的凋亡率,采用划痕愈合实验和Transwell实验检测A549细胞的迁移能力。蛋白质印迹法测定高迁移率族蛋白3(HMGB3)的表达水平。双荧光素酶分析circ_0015756与miR-515-5p、miR-515-5p与HMGB3的靶向关系。结果显示,肺癌组织中circ_0015756的相对水平显著高于癌旁组织(P0.05),miR-515-5p的相对水平显著低于癌旁组织(P0.05)。干扰circ_0015756表达后A549细胞增殖抑制率、凋亡率、miR-515-5p的相对水平显著升高(P0.05),集落形成数、迁移距离、迁移细胞数、HMGB3蛋白的相对水平显著降低(P0.05)。过表达miR-515-5p后A549细胞增殖抑制率、凋亡率显著升高(P0.05),集落形成数、迁移距离、迁移细胞数、HMGB3蛋白的相对水平显著降低(P0.05)。抑制miR-515-5p表达明显减弱干扰circ_0015756表达对A549细胞增殖、集落形成、迁移以及HMGB3蛋白表达的影响(P0.05)。circ_0015756与miR-515-5p直接结合,miR-515-5p与HMGB3直接结合。总之,干扰circ_0015756通过靶向上调miR-515-5p/HMGB3轴抑制肺癌细胞增殖和迁移,诱导细胞凋亡。     

AFAP1在博来霉素诱导的A549细胞衰老中的作用机制研究

目的:研究AFAP1在博来霉素诱导的A549细胞衰老模型中的作用及分子机制。方法:用50μg/m L的博来霉素处理A549细胞5天建立细胞衰老模型。用相同浓度的博来霉素处理细胞1-5天观察细胞从周期阻滞到衰老的过程,SA-β-Gal染色检测衰老细胞数目,用Western blot方法检测AFAP1、p21、c-Src等蛋白表达。过表达AFAP1后,观察细胞衰老状态及各蛋白表达水平变化。结果:50μg/m L的博来霉素处理A549细胞5天后可以建立细胞衰老模型,表现为BLM组SA-β-Gal阳性细胞数升高(P0.01)且细胞体积显著增大(P0.01),p21表达水平升高。在衰老的A549细胞中,AFAP1和激活型(Src p Y416)表达水平变化一致,从BLM处理后出现升高第4天开始明显下降在第5天最低,c-Src和Src p Y527表达水平不变。过表达AFAP1后再用博来霉素诱导,SA-β-Gal阳性细胞数及细胞体积、Src p Y416和p21表达与空载对照比较未发现有明显差异(P0.05)。结论:衰老的A549细胞中AFAP1表达下调,c-Src活性降低;过表达AFAP1不能减轻博来霉素诱导的A549细胞衰老,也不能抑制衰老细胞中的c-Src的活性下降。     

miR-190-5p靶向抑制PHLPP1的表达促进肺腺癌A549细胞增殖和转移

miR-190-5p是小分子非编码RNA，参与调控肺腺癌细胞的增殖和转移。对miR-190-5p调控肺腺癌细胞的增殖和转移的机制深入研究会帮助了解到肺腺癌的发生机制和探究潜在的药物干预靶点。本文研究了miR-190-5p对肺腺癌A549细胞的增殖和转移的影响，解释了miR-190-5p促进肺腺癌生长的机制；通过感染miR-190-5p的慢病毒表达系统，克隆了稳定过表达miR-190-5p的肺腺癌A549细胞系；通过生物信息学方法和荧光素酶报告实验确认了miR-190-5p的靶基因。结果发现，稳定过度表达的miR-190-5p能促进A549细胞的增殖和转移；确定了miR-190-5p的靶点是PH域富含亮氨酸重复的蛋白磷酸酶1(Leucine-rich repeat-rich protein phosphatase 1 in the PH domain,PHLPP1),miR-190-5p降低PHLPP1蛋白水平；稳定表达的miR-190-5p增加了A549细胞中E盒结合锌指蛋白1(E box-binding zinc finger protein1,TCF8/ZEB1)、锌指转录因子(Z...     

沉默BCAT1对肺癌细胞增殖、迁移及侵袭能力的影响

目的:研究BCAT1在肺癌细胞A549的增殖、迁移及侵袭能力中的作用。方法:通过小干扰RNA(si RNA)沉默A549细胞中BCAT1的表达,细胞分为对照组(Con)、BCAT1基因沉默组(si RNA-BCAT1)和si RNA阴性对照组(si RNA-NC)。利用Western blot检测si RNA对BCAT1的沉默效果;划痕愈合实验检测沉默BCAT1后A549细胞迁移能力的改变;Transwell小室侵袭实验检测沉默BCAT1后A549细胞侵袭能力的变化;MTT实验检测沉默BCAT1对A549细胞增殖能力的影响。结果:与Con组相比,si RNA-BCAT1组的BCAT1蛋白表达明显降低(P0.05),细胞划痕愈合率明显降低(P0.05),能够穿膜的细胞数明显减少(P0.05),而Con组和si RNA-BCAT1组细胞的增殖能力比较差异无明显统计学意义(P0.05)。结论:沉默BCAT1抑制A549细胞的迁移和侵袭能力,而对其增殖能力无影响。     

miR-28-5p通过靶向MTSS1调控非小细胞肺癌细胞的恶性生物学行为

[目的]探讨miR-28-5p通过靶向MTSS1调控非小细胞肺癌细胞的恶性生物学行为。[方法]用双萤光素酶检测试剂分析荧光素酶活性,同时应用RT-PCR检测MRC5细胞和A549细胞中miR-28-5p和MTSS1 mRNA水平;用Lipofectamine法将miR-NC、miR-28-5p inhibitor和miR-28-5p mimic转染到A549细胞,培养48h后分别采用MTT法、流式细胞术和Transwell法检测细胞增殖、凋亡和迁移情况,同时蛋白印迹法法检测A549细胞中MTSS1、PI3K、AKT和Caspase-3表达。[结果] miR-28-5p与MTSS1有潜在的结合位点;转染miR-28-5p mimic可明显降低MTSS1-WT的荧光素酶活性,对MTSS1-MUT没有影响,而miR-28-5p inhibitor则表现出相反作用,表明miR-28-5p与MTSS1存在靶向调节作用;A549细胞中miR-28-5p mRNA的相对表达量高于MRC5细胞(P<0.05),A549细胞中MTSS1 mRNA的相对表达量低于MRC5细胞(P<0.05);通过miR-28-5p inhibitor降低miR-28-5p后,A549细胞凋亡、MTSS1、MTSS1、PI3K、AKT和Caspase-3的表达增加,细胞增殖和迁移降低(P<0.05);通过miR-28-5p mimic增加miR-28-5p后,A549细胞凋亡、MTSS1、MTSS1、PI3K、AKT和Caspase-3的表达降低,细胞增殖和迁移增加(P<0.05)。[结论] miR-28-5p在A549细胞中高表达,通过基因干预降低miR-28-5p表达后,miR-28-5p通过靶向MTSS1的3’端非编码区,提高MTSS1的翻译水平,抑制A549细胞的恶性生物学行为。     

MiR-186-5p通过靶向调控PTTG1抑制肺腺癌细胞的上皮-间质转化

先前研究表明,miR-186-5p在人类许多恶性肿瘤中扮演抑癌基因的作用,但其在肺腺癌上皮-间质转化（epithelial-mesenchymal transition,EMT）中的作用并不明确。本研究旨在证明,miR-186-5p可通过靶向调控PTTG1抑制肺腺癌细胞的上皮-间质转化。我们首先分析了miR-186-5p在人肺癌细胞中的表达。荧光定量PCR（QRT-PCR）结果显示,与人正常肺上皮细胞BEAS-2B相比,肺腺癌细胞SPC-A1、A549中的miR-186-5p表达量明显降低。为研究miR-186-5p在肺腺癌细胞中的功能,利用GV369-miR-186-5p表达载体,实现了在A549细胞中的过表达。基因转染结合Transwell侵袭结果显示,与对照质粒转染的A549细胞相比,过表达miR-186-5p的A549细胞的体外侵袭能力明显下降。Western印迹检测细胞中EMT相关标志物揭示,GV369-miR-186-5p转染的A549细胞中的上皮-钙黏着蛋白（E-cadherin）表达明显上调,而神经-钙黏着蛋白（N-cadherin）和波形蛋白（vimentin）表达明显下调。同时,GV369-miR-186-5p转染引起其靶基因--垂体肿瘤转化基因1（pituitary tumor-transforming gene 1,PTTG1）编码蛋白在A549细胞中明显降低。重要的是,过表达miR-186-5p与敲减PTTG1均可导致上皮-钙黏着蛋白表达上调,而神经-钙黏着蛋白和波形蛋白下调|而miR-186-5p和PTTG1表达载体共转染后,3种EMT相关标志物在A549的表达与对照细胞的表达无明显差异,提示过表达PTTG1可抵消miR-186-5p对EMT相关标志物表达的影响。综上所述,miR-186-5p可通过靶向调控PTTG1抑制EMT的发生,进而抑制肺腺癌细胞的侵袭转移。     

过表达NOLC1诱导人非小细胞肺癌细胞凋亡

人核仁磷酸化蛋白1 (Nucleolar and coiledbody phosphoprotein 1,NOLC1)在癌症的发生发展过程中起着至关重要的调控作用,为探讨NOLC1对肺癌细胞的作用,本研究通过Gateway系统构建重组NOLC1腺病毒载体,成功包装NOLC1腺病毒后,分别感染正常人类胚胎肺细胞(HEL)和非小细胞肺癌细胞(A549细胞),过表达NOLC1。通过MTT实验、AnnexinV-APC/PI双染法和线粒体膜电位实验,证明与HEL细胞相比,NOLC1的过表达对A549细胞的活性降低、凋亡增加、线粒体膜电位下降影响较为显著;通过Real-time PCR检测Caspase家族、TNF与受体家族和BCL2家族基因的表达,发现过表达NOLC1明显上调了A549细胞中促凋亡基因的表达,下调了抗凋亡基因的表达,其中两种重要的促凋亡蛋白CASP8和BAX均显著上调,但是在HEL细胞中这种影响不明显。研究结果表明过表达NOLC1蛋白通过对线粒体通路和死亡受体通路的共同作用,对非小细胞癌具有显著的抗肿瘤活性。     

RNA 干扰沉默缺氧诱导因子1α逆转肺癌细胞耐药性

目的:观察RNA干扰沉默缺氧诱导因子1α(HIF-1α)对肺癌细胞耐药性的影响。方法:构建靶向HIF-1α小干扰RNA基因,并转染到人肺腺癌耐顺铂细胞株A549/DDP细胞中。逆转录聚合酶链反应RT-PCR)检测细胞的HIF-1α、多药耐药基因1(MDR-1)以多药耐药相关蛋白基因(MRP)mRNA变化,免疫细胞化学法观察干扰后HIF-1α、P-糖蛋白以及MRP蛋白的变化。MTT法检测不同浓度的顺铂作用下细胞死亡率。结果:HIF-1αsiRNA组中HIF-1α、MDR-1、MRP mRNA水平显著降低(P<0.05),且蛋白水平也显著下降(P<0.05)。HIF-1αsiRNA组细胞死亡率较未转染组均明显增高(P<0.05),转染siRNA阴性组不影响肿瘤细胞的耐药性。结论:HIF-1αsiRNA可显著降低A549/DDP细胞中HIF-1α、MDR-1、MRP表达,从而起到逆转肺腺癌A549/DDP细胞的耐药作用。     

红色诺卡氏菌细胞壁骨架对肺癌细胞的抗癌作用及机制

前人研究发现红色诺卡氏菌细胞壁骨架(N-CWS)具有较好的抗癌活性,然而其对肺癌的抗癌作用机制尚不清楚。本研究旨在揭示N-CWS对肺癌细胞的抗癌作用及机制。通过平板克隆形成实验测定N-CWS对人肺腺癌细胞系A549菌落形成的影响,发现N-CWS可按照浓度依赖性方式降低A549细胞的菌落形成能力(p0.05)。通过5-乙炔基-2'-脱氧尿苷(EdU)法测定N-CWS对肺癌细胞增殖能力的影响,发现N-CWS可按照浓度依赖性方式降低EdU阳性细胞比例(p0.05)。通过Transwell小室和伤口愈合实验评估N-CWS对肺癌细胞侵袭和迁移能力的影响,发现N-CWS以A549浓度依赖性方式降低细胞的侵袭和迁移数量及伤口愈合百分比(p0.05)。通过qRT-PCR和Western blotting检测N-CWS对A549细胞E-cadherin、IL-6和MMP-9表达的影响,发现N-CWS以浓度依赖性方式上调了A549细胞的E-cadherin mRNA和蛋白表达(p0.05),但以浓度依赖性方式下调了IL-6和MMP-9的m RNA和蛋白表达(p0.05)。本研究证实红色诺卡氏菌细胞壁骨架可按照浓度依赖性方式降低肺癌细胞的增殖、侵袭和迁移能力,其抗癌机制与上调E-cadherin和下调IL-6和MMP-9有关。     

转录因子WSTF对肺癌细胞增殖和侵袭的实验研究

目的:研究转录因子WSTF对肺癌细胞增殖和侵袭作用的影响。方法:采用慢病毒介导的基因转染方法建立A549细胞WSTF高表达细胞系A549-WSTF和空质粒对照细胞系A549-control。细胞增殖实验和克隆形成实验观察ING5过表达对肺癌A549细胞增殖能力的影响;Trans-well迁移实验和侵袭实验观察WSTF对肺癌细胞迁移和侵袭能力的影响。结果:Western blot验证A549-WSTF细胞WSTF蛋白水平显著高于对照细胞A549-control,P=0.0004。WSTF高表达明显促进了肺癌细胞的增殖能力(1-4天P值分别为0.002、0.0004、0.0002和3.21×10-5)和克隆形成能力(P=0.004);WSTF过表达还显著促进了肺癌细胞从trans-well小室迁移到下室的作用,其OD570值分别为0.626±0.013(A549-WSTF)和0.322±0.010(A549-control),P=2.37×10-5;WSTF还促进肺癌细胞穿透基质胶迁移到下室,其OD570值分别为0.600±0.027(A549-WSTF)和0.333±0.017(A549-control),P=0.0004。结论:WSTF可以促进肺癌细胞的增殖和侵袭能力而发挥促癌作用。     

C1QTNF6 regulates cell proliferation and apoptosis of NSCLC in vitro and in vivo

Objectives: Lung cancer has been reported as the leading cause of cancer-associated deaths in humans, and its incidence continues to increase in the world. A growing number of studies have shown that dysregulated genes are associated with the occurrence and poor prognosis of a variety of tumors, including non-small cell lung cancer (NSCLC). C1q/tumor necrosis factor-related protein 6 (C1QTNF6), a member of the C1q/tumor necrosis factor-related protein (CTRP) family, has been revealed to play a role in carcinogenesis and cancer progression. Nevertheless, the effects and mechanisms of C1QTNF6 in NSCLC remain unrevealed. Materials and methods: MTT (3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazoliumromide) and colony formation, flow cytometric and transwell assays were performed to explore the cell function. Real-time PCR (RT-PCR) and Western blot were used to analyze the mRNA and protein expression. Results: In the present study, we found that C1QTNF6 significantly promoted the proliferation of SPCA1 and A549 cells by MTT and colony formation assays. In addition, down-regulation of C1QTNF6 weakened the tumor growth in vivo. Besides, C1QTNF6 remarkably reduced apoptosis by flow cytometric analysis and TUNEL assay. Furthermore, the capability of migration and invasion was obviously enhanced on C1QTNF6 overexpression. Conclusion: Overall, our results demonstrated that inhibition of C1QTNF6 attenuated cell proliferation, migration, invasion and promoted apoptosis in vitro and in vivo of NSCLC. Based on the above results, our study provided us with a new and key perspective in understanding and treating NSCLC.     

LATS1过表达对肺癌A549细胞增殖及周期的影响

通过过表达手段上调大肿瘤抑制因子1（1arge tumor suppressor gene 1,LATS1）基因在A549细胞中的表达,研究LATS1对A549细胞生长和细胞周期调控的作用。构建过表达LATS1基因的慢病毒载体,转染A549N胞株,采用RT-PCR和蛋白质印迹法检测转染后A549细胞中LATS1、YAPmRNA和蛋白的表达效率;流式细胞术检测细胞凋亡、周期情况：CCK-8检测细胞的增殖水平变化。结果发现,过表达LATS1慢病毒载体转染A549细胞株后,LATS1mRNA及蛋白表达水平高于未处理组及转染空载体组,YAPmRNA及蛋白表达水平低于未处理组及转染空载体组;过表达LATS1慢病毒转染后,A549细胞增殖率从第五天开始低于对照组（P〈0．05）,过表达组细胞G1期比例明显增高（P〈0．05）,凋亡率明显增加（P〈0．05）,差异均有统计学意义。以上结果提示,LATS1可通过下调YAP的表达水平促进A549细胞的凋亡,诱导G1期阻滞,降低细胞的增殖能力。     

Suppression of type 1 Insulin-like growth factor receptor expression by small interfering RNA inhibits A549 human lung cancer cell invasion in vitro and metastasis in xenograft nude mice

Cancer invasion and metastasis, involving a variety of pathological processes andcytophysiological changes,contribute to the high mortality of lung cancer.The type 1 insulin-like growthfactor receptor (IGF-1R),associated with cancer progression and invasion,is a potential anti-invasion andanti-metastasis target in lung cancer.To inhibit the invasive properties of lung cancer cells,we successfullydown-regulated IGF-1R gene expression in A549 human lung cancer cells by small interfering RNA (siRNA)technology,and evaluated its effects on invasion-related gene expression,tumor cell in vitro invasion,andmetastasis in xenograft nude mice.A549 cells transfected with a plasmid expressing hairpin siRNA forIGF-1R showed a significantly decreased IGF-1R expression at the mRNA level as well as the proteinlevel.In biological assays,transfected A549 cells showed a significant reduction of cell-matrix adhesion,migration and invasion.Consistent with these results,we found that down-regulation of IGR-1Rconcomitantly accompanied by a large reduction in invasion-related gene expressions,including MMP-2,MMP-9,u-PA,and IGF-1R specific downstream p-Akt.Direct tail vein injections of plasmid expressinghairpin siRNA for IGF- 1R significantly inhibited the formation of lung metastases in nude mice.Our resultsshowed the therapeutic potential of siRNA as a method for gene therapy in inhibiting lung cancer invasionand metastasis.     

Egr-1基因沉默对A549细胞放射敏感性的影响

目的:探讨Egr-1基因沉默对人肺腺癌A549细胞放射敏感性的影响。方法:选用A549细胞株作为研究对象,将其分成A、B、C三组,即空白对照组(只加入RPMI-1640培养)、阴性对照组(加入LV3-NC-sh RNA)、实验组(加入EGR1-homo-2294-sh RNA),采用慢病毒介导的sh RNA干扰技术使实验组细胞Egr-1基因沉默表达。利用荧光显微镜、自动化荧光定量细胞成像分析系统分析sh RNA转染,利用FQ-PCR分析Egr-1表达,再利用细胞克隆形成实验检测细胞放射敏感性参数的差异。结果:慢病毒介导的sh RNA成功转染阴性对照组、实验组细胞;空白对照组与阴性对照组Egr-1表达无差异(P0.05),实验组与空白对照组、阴性对照组比较Egr-1均受到明显抑制(P0.05);克隆形成实验中细胞放射敏感性参数D0、SF2实验组细胞与空白对照组、阴性对照组比较均存在明显差异(P0.05)。结论:Egr-1基因沉默使A549细胞放射敏感性降低,Egr-1表达可能与肿瘤细胞对放射的敏感性有关。     

Down-regulation of N-acetylglucosaminyltransferase V by tumorigenesis- or metastasis-suppressor gene and its relation to metastatic potential of human hepatocarcinoma cells

The effects of transfection of the metastasis suppressor gene nm23-H1 and cell-cycle related tumor-suppressor gene p16 on the activity of N-acetylglucosaminyltransferase V (GnT-V) and their relations to cancer metastatic potential were investigated. After transfection of nm23-H1 into 7721 human hepatocarcinoma cells and A549 human lung cancer cells, the activities of GnT-V were decreased by 28%-42% in the cells. In contrast, when p16 was transfected into these two cell lines, the decrease of GnT-V activity was only observed in A549 cells. This was probably to be due to the obvious expression of p16 gene in parental 7721 cells and the deletion of p16 in A549 cells. The decrease of GnT-V mRNA was only observed in nm23-H1-transfected cells, but not in p16-transfected A549 cells, suggesting that these two genes regulated GnT-V via different mechanisms. Horseradish peroxidase (HRP)-lectin staining showed that the 7721 cells transfected with nm23-H1 or the A549 cells transfected with p16 displayed a decreased intensity with HRP-leucoagglutinating phytohemagglutinin and increased intensity with HRP-concanavalin A, indicating the decline of beta1,6 N-acetylglucosamine branching structure on the asparagine-linked glycans of cell-surface and intracellular glycoproteins. The nm23-H1 transfected 7721 cells also displayed some changes in metastasis-related phenotypes, including the increase in cell adhesion to fibronectin (Fn), the decline in cell adhesion to laminin (Ln), and the decreased cell migration and invasion through matrigel. Transfection of antisense GnT-V cDNA into 7721 cells resulted in a decrease of GnT-V activity, an increase of cell adhesion to Fn or Ln, and a decrease in cell migration and invasion through matrigel. These phenotypes bore similarity to those of the 7721 cells transfected with nm23-H1. Our findings indicate that the down-regulation of GnT-V by nm23-H1 contributes to the alterations in metastasis-related phenotypes, and is an important molecular mechanism of metastasis suppression mediated by nm23-H1.     

Neuropilin 1 expression correlates with the Radio‐resistance of human non‐small‐cell lung cancer cells

The purpose of this study was to determine the correlation between over‐expression of the neuropilin 1 (NRP1) gene and growth, survival, and radio‐sensitivity of non‐small cell lung carcinoma (NSCLC) cells. 3‐[4,5‐dimethylthylthiazol‐2‐yl]‐2,5 diphenyltetrazolium broide (MTT) and colony assays were then performed to determine the effect of NRP1 inhibition on the in vitro growth of NSCLC cells. The Annexin V‐Fluorescein Isothiocyanate (FITC) apoptosis detection assay was performed to analyse the effect of NRP1 enhancement on apoptosis of NSCLC cells. Transwell invasion and migration assays were employed to examine the metastatic ability of A549 cells post X‐ray irradiation. In addition, Western blot assays were carried out to detect the protein level of VEGFR2, PI3K and NF‐κB. Finally, to examine the effect of shNRP1 on proliferation and radio‐sensitivity in vivo, a subcutaneous tumour formation assay in nude mice was performed. Microvessel density in tumour tissues was assessed by immunohistochemistry. The stable transfected cell line (shNRP1‐A549) showed a significant reduction in colony‐forming ability and proliferation not only in vitro, but also in vivo. Moreover, shRNA‐mediated NRP1 inhibition also significantly enhanced the radio‐sensitivity of NSCLC cells both in vitro and in vivo. The over‐expression of NRP1 was correlated with growth, survival and radio‐resistance of NSCLC cells via the VEGF‐PI3K‐ NF‐κB pathway, and NRP1 may be a molecular therapeutic target for gene therapy or radio‐sensitization of NSCLC.