HOTAIRM1靶向miR-129-5p对胶质瘤细胞增殖、迁移、侵袭的影响

目的:研究长链非编码RNA HOTAIRM1（lncRNA HOTAIRM1）与微小RNA-129-5p（miR-129-5p）的靶向关系及其对胶质瘤细胞增殖、迁移、侵袭的影响。 方法:荧光定量PCR（qPCR）检测HOTAIRM1和miR-129-5p在人正常脑组织和胶质瘤组织中的表达。建立抑制HOTAIRM1表达细胞株,研究其对U251细胞增殖、凋亡、迁移及侵袭的影响。MTT法检测细胞增殖;流式细胞仪检测细胞凋亡;Transwell小室法检测细胞迁移和侵袭;蛋白质印迹法（Western blot）检测细胞周期蛋白D1（Cyclin D1）、p21、B细胞淋巴瘤/白血病-2（Bcl-2）和Bcl-2相关X蛋白（Bax）、上皮钙黏素（E-cadherin）、基质金属蛋白酶-2（MMP-2）水平。生物学信息预测和双荧光素酶报告基因法分析HOTAIRM1和miR-129-5p之间的靶向关系。共转染si-HOTAIRM1和anti-miR-129-5p,观察抑制miR-129-5p表达对抑制HOTAIRM1表达诱导的U251细胞增殖、凋亡、迁移及侵袭的影响。 结果:HOTAIRM1在胶质瘤组织中的表达明显上调（P<0.05）,miR-129-5p表达下调（P<0.05）。抑制HOTAIRM1表达显著降低U251细胞24 h、48 h、72 h的细胞活性、迁移细胞数、侵袭细胞数及Cyclin D1、Bcl-2、MMP-2蛋白表达量（P<0.05）,明显增加U251细胞凋亡率和p21、Bax、E-cadherin蛋白表达量（P<0.05）。miR-129-5p是HOTAIRM1的靶基因。上调或下调HOTAIRM1表达明显调控miR-129-5p表达（P<0.05）。抑制miR-129-5p表达逆转了抑制HOTAIRM1表达对U251细胞24 h、48 h、72 h的细胞活性、迁移细胞数、侵袭细胞数及Cyclin D1、MMP-2、Bcl-2蛋白表达的抑制作用,并逆转了抑制HOTAIRM1表达对U251细胞p21、E-cadherin、Bax蛋白表达和细胞凋亡率的促进作用。 结论:lncRNA HOTAIRM1通过靶向miR-129-5p影响胶质瘤细胞增殖、凋亡、迁移和侵袭。     

Prucalopride通过促进自噬抑制胶质瘤细胞U251增殖

目的:研究Prucalopride对胶质瘤U251细胞增殖、自噬、凋亡的影响,并探讨其相关信号通路。方法:通过CCK8检测细胞增殖的变化;Transwell检测迁移和侵袭的变化;细胞流式实验、Western blot检测细胞凋亡的变化;Western blot检测自噬相关蛋白LC3、Beclin1、p62的表达;AKT/mTOR通路相关蛋白的变化。结果:CCK8显示Prucalopride显著抑制U251细胞的增殖（P＜0.05）;Transwell侵袭实验显示Prucalopride可以抑制脑胶质瘤细胞的迁移和侵袭（P＜0.05）;细胞流式实验显示Prucalopride促进U251细胞的凋亡（P＜0.05）,Prucalopride处理后细胞凋亡相关蛋白Bax、Active Caspase3水平升高,Bcl-2表达降低;自噬相关蛋LC3、Beclin1表达上调,p62表达下调;p-AKT蛋白和p-mTOR蛋白水平显著降低。结论:Prucalopride通过抑制AKT/mTOR信号通路激活自噬抑制U251细胞增殖和迁移,促进其凋亡。     

Wip1基因在人脑胶质瘤组织中的表达及其与p53基因突变的相关性研究

背景与目的：野生型p53诱导的磷酸酶1（wild-type p53-induced phosphatase1,Wip1）是一种新发现的癌基因,其在多种肿瘤中存在过表达。本研究旨在探讨Wip1基因在脑胶质瘤组织中的表达及其与p53基因突变的相关性。方法：收集52例原发胶质瘤及8例脑外伤或脑出血后行内减压术的正常脑组织标本,采用实时荧光定量PCR（real-time fluorogentic quantitative,RFQ-PCR）法检测脑胶质瘤组织中Wip1mRNA的表达,Western blot法检测Wip1蛋白的表达,DNA直接测序法检测脑胶质瘤组织中p53基因的突变情况。统计学分析不同脑胶质瘤病理分级及p53的突变状态间Wip1的表达水平的差异。结果：52例脑胶质瘤中22例（42.3%）发生p53基因突变。Wip1 mRNA在高级别胶质瘤（Ⅲ～Ⅳ级）中的表达水平较低级别胶质瘤（Ⅰ～Ⅱ级）及正常脑组织中的表达要略高,但差异无统计学意义（P〈0.05）。Wip1基因在无p53基因突变的胶质瘤组织中的表达水平较p53基因突变组要高,差异有统计学意义（P=0.009）。Wip1在野生型p53的胶质瘤中存在选择性的过表达,Wip1在胶质瘤中的过表达与病理分级无明显相关,而与p53的突变状态有关。结论：Wip1基因在脑胶质瘤中存在选择性地过表达,其过表达与p53基因野生型状态相关,可能是胶质瘤恶性进展中除p53基因突变外的另一关键作用因素。     

p53基因对胶质瘤细胞系U251生长抑制作用的研究

背景与目的：肿瘤抑制基因p53是调节多种与细胞周期、凋亡、DNA修复等有关基因表达的转录因子。p53基因在大约30％的胶质瘤中发生突变，在胶质瘤的发生和发展中起重要作用。本文主要探讨野生型p53基因过表达对脑胶质瘤细胞系U251细胞生长抑制的机制。方法：通过p53腺病毒表达载体pAdCMV-p53及空载体pAdCMV-lacZ分别感染U251细胞系，RT-PCR及Westem blot方法检测转染效率；并通过MTT检测生长抑制率、流式细胞仪检测细胞周期及TUNEL检测分析细胞凋亡等指标观察p53基因对U251细胞生长的影响。结果：MOI为100时，野生型p53基因的过表达可引起U251细胞G0、G1期阻滞、诱导U251细胞凋亡以及引起U251细胞生长抑制。结论：p53基因可以通过细胞周期G0、G1期阻滞及诱导细胞凋亡抑制胶质瘤细胞系U251的生长。     

MIIP通过HDAC6参与肿瘤侵袭转移的研究进展

迁移侵袭抑制蛋白（ migration and invasion inhibitory protein,MIIP）,是近年来研究发现的潜在肿瘤转移抑制基因,定位于1p36,该区域在多种肿瘤中缺失。MIIP的定位提示其可能在肿瘤侵袭、转移中发挥作用,并且已有研究报道MIIP可抑制胶质瘤及乳腺癌的侵袭转移。本文就MIIP通过HDAC6在肿瘤侵袭转移中的作用及其分子机制作一综述。     

莱菔硫烷抑制肺癌干细胞增殖的体外实验

目的 研究莱菔硫烷（sulforaphane, SFN）对肺癌干细胞增殖的影响及其机制。方法 采用MTT法分析SFN对H460细胞增殖的影响;应用流式细胞术（FACS）检测SFN对细胞凋亡和侧群细胞比例的影响;肿瘤球培养法分析SFN对肿瘤球生长的影响;使用shRNA慢病毒载体构建β-catenin低表达细胞株,并应用蛋白电泳法检测在β-catenin正常或低表达情况下莱菔硫烷对β-catenin、Oct4、Sox2、c-Myc、Nanog等基因表达的影响。结果 SFN有效抑制H460细胞增殖,IC50为11.2 μmol/L。SFN处理72 h后,细胞凋亡呈剂量依赖性增高。SFN有效抑制原代肿瘤球和2代肿瘤球的生长,在较低浓度（1.0 μmol/L）下即有明显的抑制作用。FACS检测提示侧群细胞比例随SFN浓度增高而减少。SFN浓度依赖性地抑制β-catenin、Oct4、Sox2、c-Myc和Nanog等蛋白表达。在低表达β-catenin情况下,Oct4、Sox2、c-Myc、Nanog等基因表达水平与SFN浓度相关。结论 SFN通过β-catenin和干性相关基因（Sox2、c-Myc、Nanog和Oct4）特异地抑制肺癌干细胞的增殖。     

lncRNA LUADT1靶向miR-138-5p调控胶质瘤细胞的增殖、迁移和侵袭

目的:探讨肺腺癌相关转录本1（LUADT1）对胶质瘤细胞的增殖、迁移和侵袭的影响及分子机制。方法:将si-NC、si-LUADT1、miR-NC、miR-138-5p、pcDNA、pcDNA-LUADT1分别转染至U251细胞中,记为si-NC组、si-LUADT1组、miR-NC组、miR-138-5p组、pcDNA组、pcDNA-LUADT1组;将si-LUADT1分别与anti-miR-NC、anti-miR-138-5p共转染至U251细胞中,记为si-LUADT1+anti-miR-NC组、si-LUADT1+anti-miR-138-5p组。实时荧光定量PCR（RT-qPCR）检测LUADT1和miR-138-5p表达水平;细胞计数试剂盒8（CCK-8）检测细胞增殖活性;Transwell检测细胞迁移和侵袭;蛋白质印迹（Western blot）法检测细胞周期蛋白D1（CyclinD1）、细胞周期蛋白依赖性激酶抑制剂1A（p21）、基质金属蛋白酶2（MMP-2）、基质金属蛋白酶9（MMP-9）的表达;双荧光素酶报告实验检测lncRNA LUADT1和miR-138-5p的靶向关系。结果:胶质瘤组织中lncRNA LUADT1高表达,miR-138-5p低表达。抑制lncRNA LUADT1表达或过表达miR-138-5p,细胞活性降低,细胞迁移、侵袭数降低,CyclinD1、MMP-2、MMP-9蛋白表达水平降低,p21蛋白表达水平升高。lncRNA LUADT1靶向调控miR-138-5p,干扰miR-138-5p表达逆转了抑制lncRNA LUADT1表达对胶质瘤U251细胞增殖、迁移、侵袭的抑制作用。结论:抑制lncRNA LUADT1表达通过靶向miR-138-5p抑制胶质瘤细胞的增殖、迁移和侵袭。     

胶质瘤egr-1基因表达水平与其细胞增殖和凋亡关系的研究

目的：探讨胶质瘤细胞egr-1基因表达水平与肿瘤恶性程度、细胞增殖活性及凋亡程度的关系。方法：用原位杂交、原位细胞凋亡检测和免疫组化染色方法观察了73例不同级别的胶质瘤。结果：73例胶质瘤egr-1mRNA和EGR-1蛋白阳性表达率均为100％．这两种阳性肿瘤细胞密度均随肿瘤恶性程度升高而相应增加，不同级别组间比较差异均有显著性（P〈0．01）。73例胶质瘤增殖细胞核抗原（PCNA）阳性肿瘤细胞和凋亡肿瘤细胞检出率均为100％。随肿瘤恶性程度升高，PCNA阳性肿瘤细胞密度增加而凋亡肿瘤细胞密度减少，不同级别组间比较差异均有显著性（心0．05～0．01）。经直线相关分析证实，egr-1mRNA、EGR-1蛋白和PCNA阳性肿瘤细胞密度彼此间均呈显著性正相关（r=0．685～0．999，P〈0．01），前三种阳性肿瘤细胞密度均与凋亡肿瘤细胞密度呈显著性负相关（r=-0．758—0．775，P〈0．01）。结论：egr-1基因表达水平对评价胶质瘤生物学行为有重要参考价值。胶质瘤细胞egr-1基因表达异常增加可能是促进肿瘤细胞增殖和抑制其凋亡的重要因素，并在胶质瘤发生及恶性进展过程中均起重要作用。     

miR-377-5p通过抑制AKT1/GSK-3β通路增强食管癌细胞TE-1的放射敏感性

目的 探究miR-377-5p对食管癌细胞TE-1放射敏感性的影响及机制。方法 TE-1细胞转染miR-377-5pmimic和miR-377-5pmimic NC构建过表达miR-377-5p细胞。对转染后的TE-1细胞照射后采用平板集落形成实验检测细胞放射生物学参数(D0、Dq、SF2),Transwell小室法检测细胞侵袭能力,细胞划痕实验检测细胞迁移能力,CCK8法检测细胞活力,流式细胞术检测细胞凋亡和细胞周期,免疫印迹检测AKT1和GSK-3β磷酸化水平。结果 2、4、6、8Gy照射的集落形成率均显著下降(P<0.05),且在同一剂量下miR-377-5pmimic组细胞集落形成率均显著低于miR-377-5pmimic NC组(P<0.05)。相比于miR-377-5pmimic NC组,miR-377-5pmimic组D0、Dq、SF2均显著下降(P<0.05),放射增敏比为1.34(D0值比);0 Gy照射后细胞侵袭、迁移、增殖能力显著下降,细胞凋亡水平显著上升,细胞周期被阻滞于G1期,AKT1和GSK-3β磷酸化水平显著下降(P<0.05);4 Gy照射后细胞侵袭、迁移、增殖能力下降,细胞凋亡水平显著上升,G1期显著延长,AKT1和GSK-3β磷酸化水平亦显著下降(均P<0.001)。结论 miR-377-5p能够增加食管癌细胞TE-1的放射敏感性,其机制可能是抑制AKT1/GSK-3β信号通路。     

紫杉醇联合紫草素对U87脑胶质瘤细胞的作用及机制初探

目的:探讨紫杉醇联合紫草素通过协同作用杀伤人脑胶质瘤的作用。方法:将不同浓度的紫杉醇与紫草素单药及两种药物半量联合作用于胶质瘤细胞后,用CCK-8法检测细胞增殖抑制率,用划痕实验和Transwell法检测细胞生物学行为（迁移与侵袭）的影响,流式细胞技术检测细胞周期及凋亡率,Western-blot测定细胞外调节蛋白激酶（ERK）的蛋白表达。结果:紫杉醇与紫草素对胶质瘤细胞株U87细胞增殖具有抑制作用,且呈时间和剂量依赖性,并且发挥协同作用。紫杉醇与紫草素单独以及联合应用抑制U87细胞迁移与侵袭。两种药物联合应用促进U87细胞凋亡,紫草素组G1期的RNA含量增多,紫杉醇组及联合应用组的G2期RNA含量显著增高。Western-blot结果显示两者联合应用时,p-ERK蛋白表达降低。结论:与紫杉醇或紫草素单用组相比,两者半量联用通过协同作用能显著抑制U87胶质瘤细胞增殖、迁移、侵袭能力,促进细胞凋亡,阻滞细胞周期。紫杉醇与紫草素的协同效应机制与二者联合应用抑制p-ERK蛋白表达相关。     

Tumor-associated methylation of the putative tumor suppressor AJAP1 gene and association between decreased AJAP1 expression and shorter survival in patients with glioma

Allelic loss of the short arm of chromosome 1 has been observed frequently in a wide spectrum of cancers,most frequently in oligodendroglioma.In our previous studies,we evaluated 177 oligodendroglial tumor samples and identified the AJAP1 gene(formerly Shrew1) in the consensus region of deletion.AJAP1 is a transmembrane protein found in adheren junctions and functions to inhibit glioma cell adhesion and migration.Whereas a putative tumor suppressor gene,we did not detect AJAP1 gene mutations.In subsequent s...     

TGF-β信号通路对胶质瘤干／祖细胞的生物学效应

转化生长因子-β（transforminggrowthfactor-β,TGF-β）作为一种多功能生长因子,具有抑制神经干细胞增殖以及诱导其分化的功能。然而,TGF-β在肿瘤形成过程中具有双重性,在肿瘤形成初期TGF-β可作为抑癌因子抑制细胞增殖．促进细胞分化或凋亡：而在肿瘤发展期,TGF-β却通过促进肿瘤增殖、刺激血管增生和抑制免疫反应而成为促癌因子。目前TGF-β由抑癌因子转变成促癌因子的分子机制尚不清楚。研究发现,TGF-β信号通路在高级别胶质瘤中高度激活表达,并且TGF-β活性高的胶质瘤患者的临床预后极差。胶质瘤干／祖细胞作为胶质瘤发生发展的起源．是胶质瘤治疗成败的关键。因此,研究TGF-β信号通路在胶质瘤干／祖细胞中的生物学效应显得至关重要。本文就TGF-β信号通路在肿瘤干细胞和胶质瘤干／祖细胞的增殖、分化、血管生成、转移等方面的作用作一综述．     

Silencing Pre-B-cell leukemia homeobox 3 decreases the proliferation of human glioma cells in vitro and in vivo

Among primary brain tumors, gliomas are the most common and most aggressive, with a poor prognosis and limited treatment options. Thus, it is essential to determine the mechanisms involved in glioma development to develop effective therapies for glioma patients. Pre-B-cell leukemia homeobox 3 (PBX3), a critical member of the PBX family, is frequently overexpressed in multiple human malignancies. However, the expression patterns and biological functions, as well as the involved molecular functions of PBX3 in human gliomas remain largely unknown. In this study, we demonstrate that PBX3 expression is increased in both human glioma tissues and cell lines compared with their normal counterparts. These results suggested that PBX3 might be involved in glioma progression. Thus, the role of PBX3 in glioma cell proliferation was investigated using genetic knockdown and overexpression methods. The results showed that PBX3 knockdown inhibited glioma cell proliferation and induced apoptosis, while PBX3 overexpression significantly promoted glioma cell proliferation. Mechanistically, we found that PBX3 promoted cell proliferation by modulating cell cycle progression. A xenograft LN229 model was used to confirm that PBX3 depletion decreased tumor growth in vivo. In summary, our findings reveal that PBX3 may be a potential therapeutic target in gliomas.     

Gli1 inhibition induces cell-cycle arrest and enhanced apoptosis in brain glioma cell lines

The Hedgehog (HH)-Gli1 signaling pathway plays an important role in the patterning and development of the central nervous system during embryogenesis. Recent data have shown its possible involvement in a subset of human gliomas, and inhibition of the pathway resulted in tumor suppression in both in vitro and in vivo studies. The underlying mechanisms of tumor suppression, however, remain to be fully elucidated. Here, we investigated Gli1 expression in 65 surgically resected malignant glioma tissues and found the Ki-67 labeling index to be higher in Gli1-positive gliomas than in Gli1-negative gliomas. Depletion of Gli1 expression by small interfering RNA (siRNA) interference led to remarkably decreased cell proliferation and enhanced apoptosis in U87 glioma cell line. To explore the molecular mechanisms of the phenotypic changes, we performed real-time quantitative RT-PCR analysis to monitor the changes of a series of genes which play critical roles in the regulation of cell cycle and apoptosis. The result showed that downregulation of G₁ cyclins, downregulation of Bcl-2, and upregulation of p21 were detected after Gli1 downregulation. Additionally, cyclopamine was used to inhibit the HH signaling activity as an indirect approach to decrease Gli1 expression, and we observed that cyclopamine exclusively inhibited cell growth in HH-pathway-active glioma cell lines. The cell phenotypic and molecular changes induced by cyclopamine were consistent with those caused by siGli1 interference. In conclusion, our findings support an important role of Gli1 in cell-cycle and apoptosis regulation in human brain gliomas; hence, it can serve as a potential target of new therapeutic strategies for these diseases.     

不同病理级别胶质瘤细胞中IDH1基因变异表达观察

背景与目的:胶质瘤是最常见的成人原发性神经系统恶性肿瘤,具有较高的病死率和病残率。深入研究胶质瘤的发生发展,无论对于其诊断还是治疗,都具有重要意义。本文通过观察异柠檬酸脱氢酶1(IDH1)基因变异在不同病理级别胶质瘤中表达,初步分析IDH1基因变异与胶质瘤病理分级的相关性及意义。方法:采用直接测序法对30例不同病理级别胶质瘤标本进行IDH1基因变异检测,并取5例外伤额颞叶减压脑组织标本作为对照。比色法计算肿瘤组织内IDH1酶活力,结果采用SPSS13.0进行统计学分析。结果:30例胶质瘤标本中16例(53.33%)发生IDH1基因变异,并与肿瘤病理分级具有相关性,变异后酶活力下降明显。结论:IDH1基因变异在胶质瘤中发生频率较高,变异后酶活力下降,将影响胶质瘤的发生发展。     

Knockdown of lncRNA PVT1 Inhibits Glioma Progression by Regulating miR-424 Expression

Plasmacytoma variability translocation 1 (PVT1), an oncogene, has been reported to be highly expressed in many tumors, including human glioma, gastric cancer, and non-small cell lung cancer. Functionally, it could also regulate the development of tumor cells. However, its specific roles and pathogenesis in human gliomas are still not clear. This study investigated the function and mechanism of PVT1 knockdown in the proliferation and malignant transformation of human gliomas. We first examined the expression levels of PVT1 and miR- 424 in human glioma tissues and cell lines. We also used gene manipulation techniques to explore the effects of PVT1 knockdown on cell viability, migration, invasion, and miR-424. We found that PVT1 knockdown effectively inhibited cell viability, migration, and invasion of human glioma cells and increased miR-424 expression. Based on the negative correlation between PVT1 and miR-424, we then confirmed the direct interaction between PVT1 and miR-424 using RNA immunoprecipitation (RIP) and luciferase reporter assays. Further, we established a xenograft nude mouse model to determine the role and mechanism of PVT1 on tumor growth in vivo. In addition, PVT1 knockdown was shown to promote miR-424 in vivo. In summary, the present study demonstrated that PVT1 knockdown could negatively regulate miR-424 to inhibit human glioma cell activity, migration, and invasiveness. PVT1 knockdown could negatively regulate miR-424 to inhibit cellular activity, migration, and invasiveness in human gliomas, which explained the oncogenic mechanism of PVT1 in human gliomas. It also suggested that PVT1 might be a novel therapeutic target for human gliomas.     

Upregulation of LRIG1 suppresses malignant glioma cell growth by attenuating EGFR activity

Activated epidermal growth factor receptor (EGFR) has emerged as an important therapeutic target for a variety of solid tumors, particularly malignant gliomas. A recently discovered transmembrane glycoprotein, LRIG1, antagonizes the activity of epidermal growth factor receptor family receptor tyrosine kinases and acts as a negative feedback loop of EGFR and proposed tumor suppressors. The aim of this study was to investigate the impact of LRIG1 on the biological features of glioma cells and the possible mechanisms of enhanced apoptosis induced by upregulation of LRIG1. We observed that the expression of LRIG1 was decreased, while the expression of EGFR was increased in the majority of astrocytomas, and the ratio of EGFR/LRIG1 was increased by sixfold in tumors versus corresponding non-neoplastic tissue. Upregulation of LRIG1, followed by a decrease of EGFR on the cytomembrane of the cells, induced cell apoptosis and cell growth inhibition, and further reversed invasion in glioma cell lines and primary glioma cells. Our study now clearly indicates that LRIG1 indeed affects cell fate and biology behaviors of the cells in vitro by inhibiting phosphorylation of downstream MAPK and AKT signaling pathway, and the elevated release level of caspase-8 might contribute to the enhanced apoptosis in LRIG1 transfected glioma cells. Taken together, these findings provide us with an insight into LRIG1 function, and we conclude that LRIG1 evolved in gliomas as a rare feedback negative attenuator of EGFR and could offer a novel therapeutic target to treat patients with malignant gliomas. Fei Ye and Qinglei Gao contributed equally to this work.     

Blockage of angiotensin II type I receptor decreases the synthesis of growth factors and induces apoptosis in C6 cultured cells and C6 rat glioma

Angiotensin II (Ang II) is a main effector peptide in the renin-angiotensin system and participates in the regulation of vascular tone. It also has a role in the expression of growth factors that induce neovascularisation which is closely associated to the growth of malignant gliomas. We have shown that the selective blockage of the AT1 receptor of angiotensin inhibits tumour growth, cell proliferation and angiogenesis of C6 rat glioma. The aim of this study was to study the effects of the blockage of AT1 receptor on the synthesis of growth factors, and in the genesis of apoptosis in cultured C6 glioma cells and in rats with C6 glioma. Administration of losartan at doses of 40 or 80 mg kg(-1) to rats with C6 glioma significantly decreased tumoral volume and production of platelet-derived growth factor, vascular endothelial growth factor and basic fibroblast growth factor. It also induced apoptosis in a dose-dependent manner. Administration of Ang II increased cell proliferation of cultured C6 cells which decreased by the administration of losartan. Our results suggest that the selective blockage of AT1 diminishes tumoral growth through inhibition of growth factors and promotion of apoptosis.