过表达Snail增强肺癌细胞A549的体外侵袭能力

用锌指转录因子Snail诱导肺癌细胞A549发生上皮细胞-间质转化(epithelial-mesenchymal transition,EMT),检测肺癌发生EMT后细胞侵袭能力的变化,为临床筛选分子靶向药物提供依据.构建pcDNA3.1-snail载体,用pcDNA3.1-snail及空pcDNA3.1载体转染肺癌A549细胞后,进行G418筛选;光镜观察培养后细胞形态学的改变、免疫细胞化学与免疫荧光检测细胞表达E-钙黏着蛋白(E-cadherin)、波形蛋白(vimentin)的改变,Western印迹检测细胞中E-钙黏着蛋白和波形蛋白的改变,Transwell侵袭小室法进行细胞体外侵袭能力检测.采用pcDNA3.1-snail转染细胞后,A549细胞变得细长,细胞融合度降低.免疫细胞化学、免疫荧光、Western印迹结果显示,E-钙黏着蛋白表达降低,波形蛋白表达升高;transwell侵袭小室法结果显示,过表达Snail的A549细胞穿透matrigel胶的细胞数明显增多.结果提示,Snail能有效诱导肺癌发生EMT,并且能增强肺癌的体外侵袭能力.     

肿瘤相关成纤维细胞对非小细胞肺癌恶性生物学行为影响

目的:探讨肿瘤相关成纤维细胞(Tancer Associated Fibroblast,TAF)对非小细胞肺癌(Non-small Cell Lung Cancer,NSCLC)恶性生物学行为的影响。方法:选取在本院肿瘤科住院手术的非小细胞肺癌患者,收集术后肺癌标本,马松三色染色(Masson Trichrome Stain)和天狼星红染色(Sirius Red Stain)观察肺癌组织(Lung Cancer Tissue,LCT)、癌旁组织(Pericarcinomatous Tissue,PCT)和正常组织(Normal Tissue,NT)中TAF的表达情况;体外将非小细胞肺癌细胞A549与非小细胞肺癌成纤维细胞P-gp共培养,CCK-8检测共培养前后A549细胞增殖能力;细胞划痕和Trans-well实验分别检测A549细胞迁移和侵袭能力;q RT-PCR和Western blot检测A549细胞上皮间质转化(Epithelial Mesenchymal Transition,EMT)标志蛋白E-cadherin、N-cadherin和Vimentin的表达。结果:Masson和Sirius染色结果显示:肺癌组织中纤维的表达明显高于癌旁组织;与P-gp共培养的A549细胞的增殖、迁移和侵袭能力及上皮间质转化相关蛋白N-cadherin和Vimentin表达均明显高于阴性对照组(P0.05),而E-cadherin的表达明显降低(P0.05)。结论:TAF可能通过诱导非小细胞肺癌细胞EMT的发生从而促进非小细胞肺癌的增殖、迁移和侵袭等恶性生物学行为。     

薯蓣皂苷激活p38MAPK/FOXO3a信号抑制三阴性乳腺癌细胞上皮–间质转化及侵袭

该研究探讨了薯蓣皂苷(Dioscin)对三阴性乳腺癌MDA-MB-231、BT549细胞体外侵袭及上皮–间质转化(epithelial to mensenchymal transition,EMT)的影响及其作用机制。以正常人乳腺上皮MCF-10A细胞为对照,通过MTS法、克隆形成实验检测细胞增殖能力;Transwell实验检测细胞侵袭、迁移能力;Western blot法检测p38MAPK、p-p38MAPK、FOXO3a及上皮–间质转化(epithelial to mensenchymal transition,EMT)相关标志物的表达。结果显示,Dioscin能明显抑制MDA-MB-231、BT549细胞的增殖,且具有浓度依赖性,对MCF-10A细胞抑制作用较弱;Dioscin处理后肿瘤细胞的侵袭、迁移能力明显降低,Dioscin可显著下调细胞间质样标志物波形蛋白(vimentin)、N-钙黏蛋白(N-cadherin)并促进上皮样标志物E-钙黏蛋白(E-cadherin)的表达,EMT关键转录因子Snail的表达也受到抑制。进一步研究发现,Dioscin能够上调p38MAPK磷酸化水平并促进转录因子FOXO3a的表达,而干扰FOXO3a能够逆转Dioscin对细胞EMT及侵袭的抑制作用。以上研究表明,Dioscin能够抑制三阴性乳腺癌细胞EMT及体外侵袭、迁移能力,其机制可能与Dioscin调控p38MAPK/FOXO3a信号有关。     

Kin17在非小细胞肺癌侵袭转移中的作用及其机制研究

目的:探究核蛋白17(Kin17)在非小细胞肺癌侵袭转移中的作用及其机制研究。方法:采用核糖核苷酸测序(RNA-seq)技术比较A549-KD组细胞与A549-NC组细胞中的信使RNA(mRNA)表达谱,从中筛选出表达差异较大的基因。采用蛋白免疫印迹(Western blot)方法对A549-NC组、A549-KD组和A549-KD+信号转导与转录激活因子3(STAT3)组细胞中Kin17、STAT3、磷酸甘油醛脱氢酶(GAPDH)、E-钙黏蛋白(E-cadherin)、波形蛋白(Vimentin)、碱性螺旋-环-螺旋转录因子(Twist)和转录因子(Snail)表达水平进行检测,采用划痕实验检测细胞侵袭能力,采用Transwell实验检测细胞迁移能力,采用免疫荧光实验检测Kin17和STAT3蛋白在细胞中的定位情况。结果:与A549-NC组相比,A549-KD组的STAT3表达水平下降(P0.05)。A549-KD组E-cadherin表达水平高于A549-NC组和A549-KD+STAT3组,而Vimentin、Twist和Snail表达水平低于A549-NC组和A549-KD+STAT3组(P0.05)。A549-KD组划痕愈合率、细胞迁移率低于A549-NC组和A549-KD+STAT3组(P0.05)。Kin17和STAT3蛋白共定位于细胞核中。结论:在非小细胞肺癌中Kin17可能通过促进STAT3表达水平以促进非小细胞肺癌细胞上皮-间质转化(EMT)、侵袭和转移,Kin17及STAT3在非小细胞肺癌患者诊断和治疗中具有一定临床价值。     

Sprouty-2对胃癌细胞上皮间质转化及侵袭转移的影响

目的:研究Sprouty2(SPRY2)基因在胃癌肿瘤细胞上皮间质转化(EMT)和侵袭转移的影响。方法:体外培养人胃癌细胞(BGC-823),采用慢病毒介导的sh RNA沉默SPRY2基因,并用实时定量PCR与Western blot检测其SPRY2、E-钙黏蛋白(E-cadherin)、波形蛋白(vimentin)的表达,采用细胞划痕实验、Transwell实验检测SPRY2基因沉默后的胃癌细胞侵袭转移能力变化。结果:在慢病毒介导sh RNA沉默SPRY2基因的人胃癌BGC-823细胞中,SPRY2的m RNA和蛋白表达明显降低(P0.05),SPRY2沉默后人胃癌细胞E-cadherin的蛋白表达增多(P0.05),vimentin的蛋白表达减少(P0.05)。此外,SPRY2沉默后,胃癌细胞迁移能力和侵袭能力明显减弱(P值均P0.05)。结论:Sprouty-2基因通过调节E-cadherin与vimentin的表达参与胃癌细胞的上皮-间质转化,进而促进胃癌细胞的迁移与侵袭。     

沙棘总黄酮抑制肺癌A549增殖和迁移作用及机理

为探究三种沙棘总黄酮(TFH)对非小细胞肺癌A549细胞增殖及迁移的影响,并探讨其分子作用机制,选择不同浓度的西藏沙棘(Hippophae tibetana Schlecht)、中国沙棘(H.rhamnoides L.subsp.sinensis Rousi)、肋果沙棘(H.neurocarpa)总黄酮作用于A549细胞。通过MTT检测细胞相对活力,平板克隆形成实验及软琼脂克隆形成实验检测细胞克隆形成能力,流式细胞仪AnnexinV/PI双染法检测细胞凋亡比例。选择效果最佳的西藏沙棘总黄酮应用细胞划痕实验及Transwell实验分析该化合物对肺癌细胞迁移侵袭能力的影响。Western blot检测MMP9、E-cadherin等侵袭迁移相关蛋白表达。敲低E-cadherin基因检测沙棘总黄酮对细胞迁移能力的影响。结果显示,三种沙棘总黄酮均对A549细胞系具有增殖抑制作用,抑制作用依次为:西藏沙棘中国沙棘肋果沙棘。西藏沙棘总黄酮可显著性抑制非小细胞肺癌A549细胞侵袭迁移能力(P0.05)。实验组中MMP9、MMP2、TGF-β、N-cadherin表达水平显著降低,E-cadherin表达水平上调。我们发现在A549细胞中敲低E-cadherin,西藏沙棘总黄酮可逆转迁移增加。以上研究表明西藏沙棘总黄酮对肺癌A549增殖抑制作用具有明显的优势,且西藏沙棘总黄酮可明显抑制肺癌A549细胞的侵袭迁移能力,并可能与下调细胞中的TGF-β抑制MMP9表达并阻止肺癌EMT有关。     

脐带间充质干细胞恶性分化并促进肺癌A549细胞移植瘤生长及转移

目的探讨人脐带来源的间充质干细胞(human umbilical cord mesenchymal stem cells,hUCMSCs)对裸鼠肺癌移植瘤生长及转移的影响。方法将24只裸鼠随机分为4组,分别为A549细胞单独注射组(A549组)、hUCMSCs单独注射组(MSCs组)、A549细胞与正常人皮肤成纤维细胞(skin fibroblasts,SKs)共同注射组(A549+SKs组)、hUCMSCs与A549细胞共注射组(A549+MSCs组)。HE染色和免疫组织化学染色确定hUCMSCs注射裸鼠皮下结节性质;流式细胞分选技术分选出各组移植瘤瘤组织中的A549细胞;实时荧光定量PCR和Westernblot检测A549细胞中上皮-间质转化(epithelial-mesenchymal transition,EMT)相关分子标志物的表达差异。结果 hUCMSCs注射后,hUCMSCs发生恶性分化,hUCMSCs与A549细胞共注射后肺癌移植瘤体积明显大于单独A549注射组和A549与SKs共注射组;2只A549与hUCMSCs共注射组裸鼠出现了肺癌肝脏转移,而A549组与A549+SKs组的全部6只裸鼠均没有发现肝脏转移。A549与MSCs共注射组A549细胞中上皮表型特征分子E-cadherin、β-catenin mRNA相对表达量和β-catenin蛋白表达水平高于A549组与A549+SKs组,E-cadherin蛋白表达水平明显高于A549+SKs组,间质表型特征分子N-cadherin和vimentin蛋白表达水平明显低于A549组与A549+SKs组,EMT转录调控因子twist蛋白表达水平低于A549组与A549+SKs组。结论 hUCMSCs可以自我恶性分化;hUCMSCs能促进肺癌A549细胞移植瘤的生长与转移;hUCMSCs增强A549细胞侵袭、转移的机制不是通过诱导A549细胞发生EMT(上皮-间质转化)。     

TGF-β1促进人子宫颈癌细胞Siha的侵袭、迁移及其机制研究

探讨转化生长因子-β1(TGF-β1)对人子宫颈癌细胞Siha侵袭、迁移能力的影响及其可能的分子机制。用5 ng/m L TGF-β1作用Siha细胞72 h,通过倒置显微镜、CCK-8实验、单细胞克隆形成实验、细胞黏附实验和Transwell小室实验分别观察TGF-β1作用前后Siha细胞形态、增殖能力、克隆形成能力、黏附能力、迁移及侵袭能力的改变;Western blot检测TGF-β1作用前后基质金属蛋白酶-2(MMP-2)、MMP-9、VEGF、CFTR、P50、P65、E-cadherin及Vimentin蛋白表达的变化。结果表明,5 ng/m L TGF-β1作用Siha细胞72 h后,Siha细胞出现上皮细胞向间质细胞形态转变、黏附能力减弱、迁移和侵袭能力增强,伴随MMP-2、MMP-9、VEGF、CFTR、P50、P65和Vimentin表达上调,E-cadherin表达下调。该研究表明,TGF-β1可能通过诱导Siha细胞发生上皮–间质转化及上调MMP-2、MMP-9和VEGF的表达,促进Siha细胞的侵袭转移。     

白皮杉醇对子宫内膜癌HEC-1A细胞增殖、迁移和侵袭的影响

本研究旨在考察白皮杉醇(piceatannol, PIC)对子宫内膜癌细胞HEC-1A的初步抗肿瘤作用。分别通过CCK-8实验、平板克隆形成实验、流式细胞术、划痕损伤修复实验和Transwell小室实验检测不同浓度的PIC对HEC-1A细胞增殖、凋亡、迁移和侵袭能力的影响。Western blot实验检测细胞增殖相关蛋白和侵袭迁移相关蛋白的表达水平。结果显示，与空白组相比，PIC能显著抑制HEC-1A细胞增殖、克隆形成能力、诱导其凋亡并减少细胞迁移距离和侵袭细胞数(P<0.01),下调p-Akt、p-Erk1/2、p-p38MAPK、β-catenin、CD44和Slug蛋白的表达水平，上调E-cadherin蛋白的表达水平(P<0.01)。综上所述，PIC呈浓度依赖性抑制子宫内膜癌HEC-1A细胞的增殖、迁移与侵袭，其机制可能与抑制AKT/ERK/MAPK信号通路和影响Wnt/β-catenin信号通路和上皮-间质转化标志物的改变有关。     

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。     

肝细胞生长因子诱导人肝癌细胞上皮间质化

上皮间质转化（epithelial-mesenchymal transition,EMT）与肿瘤侵袭转移密切相关.虽然肝细胞生长因子（hepatocyte growth factor,HGF）已被证实为肿瘤EMT的主要诱导剂,但是HGF诱导肿瘤EMT发生的分子机制尚不完全清楚.本研究旨在探讨Snail在HGF诱导肝癌细胞上皮间质转化中的作用.用HGF处理肝癌HepG2和Hep3B细胞,显微镜观察细胞形态变化,划痕试验及Transwell试验检测细胞迁移能力,Western印迹检测Met,AKT的磷酸化及蛋白质表达的变化,Western印迹与real-time RT-PCR检测上皮细胞表面标志E-Cadherin和间质细胞表面标志N-Cadherin、Fibronectin的表达变化,以及EMT相关转录因子的表达变化.经HGF处理的HepG2、Hep3B细胞,Met和AKT的磷酸化水平显著增强;相差倒置显微镜下观察细胞形态向间质型细胞形态转化;细胞划痕和Transwell试验检测细胞的迁移能力较对照组显著增强;Real-time RT-PCR和Western印迹实验显示HGF的诱导能上调间质标记蛋白的表达及下调上皮型标志蛋白的表达.进一步发现,HGF能上调转录因子Snail的表达,干扰Snail能逆转HGF对HepG2和Hep 3B细胞EMT发生的诱导作用.由此可见,HGF可能通过诱导Snail的表达促进肝癌细胞EMT的发生.这为阐明肝癌细胞侵袭转移机制,以及肝癌的防治提供新线索.     

Transforming growth factor-β1 promotes lung adenocarcinoma invasion and metastasis by epithelial-to-mesenchymal transition

Lung cancer is a highly malignant carcinoma, and most deaths of lung cancer are caused by metastasis. The alterations associated with epithelial-to-mesenchymal transition (EMT) may be related to the cancer cell metastasis. Nevertheless, the mechanism of lung cancer metastasis remains unclear. We conducted a study in vitro to investigate whether transforming growth factor-β1 (TGF-β1) could induce changes of, such as cell morphology, expression of relative protein markers, and cellular motile and invasive activities. In this research, the changes of cell morphology were first investigated under a phase contrast microscope, then western blotting was employed to detect the expression of E-cadherin, vimentin, and fibronectin, and finally cell motility and invasion were evaluated by cell wound-healing as well as invasion assays. The data indicated that human lung adenocarcinoma cell lines, A-549 and PC-9 cells of epithelial cell characteristics, were induced to undergo EMT by TGF-β1. Following TGF-β1 treatment, cells showed dramatic morphological changes assessed by phase contrast microscopy, accompanied by decreased epithelial marker E-cadherin and increased mesenchymal markers vimentin and fibronectin. More importantly, cell motility and invasion were also enhanced in the EMT process. These results indicated that TGF-β1 may promote lung adenocarcinoma invasion and metastasis via the mechanism of EMT.     

Mesenchymal stem cells promote cell invasion and migration and autophagy‐induced epithelial‐mesenchymal transition in A549 lung adenocarcinoma cells

Mesenchymal stem cells (MSCs) are recruited into the tumour microenvironment and promote tumour growth and metastasis. Tumour microenvironment‐induced autophagy is considered to suppress primary tumour formation by impairing migration and invasion. Whether these recruited MSCs regulate tumour autophagy and whether autophagy affects tumour growth are controversial. Our data showed that MSCs promote autophagy activation, reactive oxygen species production, and epithelial‐mesenchymal transition (EMT) as well as increased migration and invasion in A549 cells. Decreased expression of E‐cadherin and increased expression of vimentin and Snail were observed in A549 cells cocultured with MSCs. Conversely, MSC coculture‐mediated autophagy positively promoted tumour EMT. Autophagy inhibition suppressed MSC coculture‐mediated EMT and reduced A549 cell migration and invasion slightly. Furthermore, the migratory and invasive abilities of A549 cells were additional increased when autophagy was further enhanced by rapamycin treatment. Taken together, this work suggests that microenvironments containing MSCs can promote autophagy activation for enhancing EMT; MSCs also increase the migratory and invasive abilities of A549 lung adenocarcinoma cells. Mesenchymal stem cell‐containing microenvironments and MSC‐induced autophagy signalling may be potential targets for blocking lung cancer cell migration and invasion.     

Dioscin suppresses TGF-β1-induced epithelial-mesenchymal transition and suppresses A549 lung cancer migration and invasion

Epithelial-to-mesenchymal transition (EMT), an important cellular process, occurs during cancer development and progression, has a crucial role in metastasis by enhancing the motility of tumor cells. Dioscin is a polyphenolic component isolated from Phyllanthus amarus, which exhibits a wide range of pharmacological and physiological activities, such as anti-tumor, anti-inflammatory, anti-obesity, anti-fungal, and anti-viral activities. However, the possible role of dioscin in the EMT is unclear. We investigated the suppressive effect of dioscin on the EMT. Transforming growth factor-beta 1 (TGF-β1) is known to induce EMT in a number of cancer cell types and promote lung adenocarcinoma migration and invasion. To verify the inhibitory role of dioscin in lung cancer migration and invasion, we investigated the use of dioscin as inhibitors of TGF-β1-induced EMT in A549 lung cancer cells in vitro. Here, we found that dioscin prominently increased expression of the epithelial marker E-cadherin and expression of the mesenchymal marker N-cadherin and Snail during the TGF-β1-induced EMT. In addition, dioscin inhibited the TGF-β1-induced increase in cell migration and invasion of A549 lung cancer cells. Also, dioscin remarkably inhibited TGF-β1-regulated activation of MMP-2/9, Smad2, and p38. Taken together, our findings provide new evidence that dioscin suppresses lung cancer migration, and invasion in vitro by inhibiting the TGF-β1-induced EMT.     

Differential susceptibility to epithelial-mesenchymal transition (EMT) of alveolar, bronchial and intestinal epithelial cells in vitro and the effect of angiotensin II receptor inhibition

The generation of myofibroblasts via epithelial-mesenchymal transition (EMT), a process through which epithelial cells lose their polarity and become motile mesenchymal cells, is a proposed contributory factor in fibrosis of a number of organs. Currently, it remains unclear to what extent epithelia of the upper airways and large intestine are susceptible to this process. Herein, we investigated the ability of model cell lines of alveolar (A549), bronchial (Calu-3) and colonic (Caco-2) epithelial cells to undergo EMT when challenged with transforming growth factor-β1 (TGF-β1) and other pro-inflammatory cytokines. Western blot and immunofluorescence microscopy demonstrated that A549 cells readily underwent EMT, as evidenced by a spindle-like morphology, increase in the mesenchymal marker, vimentin, and down-regulation of E-cadherin, an epithelial marker. In contrast, neither Calu-3 nor Caco-2 cells exhibited morphological changes nor alterations in marker expression associated with EMT. Moreover, whilst stimulation of A549 cells enhanced migration and reduced their proliferative capacity, no such effect was observed in epithelial cell lines of the bronchus or colon. In addition, concomitant treatment of A549 cells with telmisartan, an angiotensin II receptor antagonist with antifibrotic properties, was found to reduce cytokine-induced collagen I production and cell migration, although expression levels of vimentin and E-cadherin remained unaltered. Mechanistically, telmisartan failed to inhibit phosphorylation of Smad2/3. Together, these results, using representative in vitro models of the alveolus, bronchus and colon, tentatively suggest that epithelial cell plasticity and susceptibility to EMT may differ depending on its tissue origin. Furthermore, our investigations point to the beneficial effect of telmisartan in partial abrogation of alveolar EMT.     

沉默FOXQ1可逆转SW480细胞的上皮-间质转化

FOXQ1是FOX家族的的重要成员之一,其参与了多种人类肿瘤的上皮间质转化(epithelial- mesenchymal transition,EMT).本研究设计合成了FOXQ1基因的shRNA（short hairpin RNA）,用此转染SW480细胞,通过显微镜观察细胞形态,Transwell小室、细胞黏附试验检测转移能力及黏附能力,以探索FOXQ1与结直肠癌细胞EMT的关系.结果显示,沉默FOXQ1后,SW480细胞顶底极性及细胞间紧密连接增加,侵袭、迁移的细胞数目减少,同种黏附能力增加,异种黏附能力降低.进一步的机制研究表明,沉默FOXQ1基因可以导致SW480细胞的上皮标志因子E-cadherin表达显著增高,而间质细胞标志因子N-cadherin、Vimentin及MMP2表达均降低.以上结果表明,沉默FOXQ1基因可以逆转SW480细胞EMT,其机制可能与E-cadherin的上调和N cadherin、Vimentin、MMP2的下调有关,这为进一步研究FOXQ1在结直肠癌发生发展中的作用提供实验基础.