RGD肽对肺癌A549 细胞增殖侵袭能力的影响及其机制研究

目的:研究RGD肽对肺癌A549细胞增殖凋亡及侵袭迁移的影响,并探讨其作用机制。方法:不同浓度RGD肽处理肺癌A549细胞后,MTT检测肺癌细胞的增殖能力,流式细胞仪检测肺癌细胞凋亡及周期分布,Transwell检测其迁移及侵袭能力的变化,Western blot检测RGD肽对肺癌A549细胞MMP2、MMP9的表达水平影响。结果:当RGD肽浓度增加至50 mg/L时,肺癌A549细胞增殖明显受到抑制,且这种抑制作用呈剂量依赖关系;RGD肽组A549细胞G0/G1期细胞比例增高,细胞凋亡率由(6.1±0.1)%增至(15.2±0.5)%;在迁移和侵袭试验中,RGD肽组A549细胞的穿膜细胞数分别由123±10和43±10降至45±5和18±5;RGD肽组A549细胞MMP2、MMP9表达水平显著降低。结论:RGD肽对肺癌A549细胞的增殖有明显抑制作用,并促进其凋亡,可能与RGD肽改变其周期分布有关,RGD肽可明显抑制A549细胞的迁移及侵袭,可能与其下调MMP2、MMP9的表达相关。     

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。     

姜黄素对A549肺癌细胞增殖、侵袭和迁移的抑制作用及与Keap1/Nrf2信号通路的关系

目的探究姜黄素对肺癌A549细胞增殖、侵袭和迁移的抑制作用及其机制。方法通过MTT法检测姜黄素对A549细胞增殖能力的影响;通过流式细胞术测定姜黄素对A549细胞凋亡的调节作用;通过Transwell试验,观察姜黄素对肺癌A549细胞的侵袭和迁移能力的影响;采用Western blot实验和RT-PCR实验,观察姜黄素对其Keap1/Nrf2信号通路的调节作用。结果增殖实验、凋亡实验和Transwell实验显示,姜黄素能够显著性抑制癌细胞的增殖、侵袭和迁移,并能够促进其凋亡。Western blot检测显示姜黄素能够显著抑制Keap1和Nrf2表达;RT-PCR实验结果显示姜黄素能够显著抑制Keap1mRNA和Nrf2 mRNA表达。结论姜黄素可能通过抑制Keap1/Nrf2信号通路蛋白的表达而抑制肺癌A549细胞的增殖、迁移和侵袭,并促进其凋亡。     

长链非编码RNA SNHG17通过抑制p57表达促进肺癌进展

目的:分析肺癌中长链非编码RNA(lncRNA)小核仁RNA宿主基因17(SNHG17)与p57的表达相关性及功能联系。方法:通过starBase数据库分析SNHG17和p57在肺癌组织和正常组织中的表达差异;采用人正常肺上皮细胞BEAS-2B和人肺癌细胞系A549、H1975进一步分析SNHG17和p57在肺癌细胞和正常肺细胞中的表达差异;采用qRT-PCR和Western印迹检测si-SNHG17在mRNA和蛋白表达方面对SNHG17和p57的影响;采用CCK-8法检测siSNHG17对A549细胞增殖的影响;采用Transwell法检测si-SNHG17对A549细胞迁移和侵袭能力的影响。结果:通过数据分析发现SNHG17在肺腺癌和肺鳞癌组织中显著高表达,而p57在肺腺癌和肺鳞癌组织中却显著低表达;与正常肺细胞相比,SNHG17和p57在肺癌细胞中的表达趋势与在肺癌组织中一致;SNHG17和p57的表达呈负相关;沉默SNHG17使p57的表达一定程度上调,A549细胞的增殖、迁移和侵袭能力受到抑制。结论:SNHG17在肺癌中高表达,促进肺癌细胞增殖,并通过调节p57的表达来抑制肺癌细胞的增殖和迁移。SNHG17和p57在肺癌中的具体作用机制仍有待进一步研究。     

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。     

lncRNA BLACAT1通过抑制miR-374b-5p促进非小细胞肺癌细胞增殖和转移

目的:研究长链非编码RNA BLACAT1在非小细胞肺癌发生和转移过程中的作用机制。方法:starBase软件分析TCGA数据库中肺腺癌及肺鳞癌与癌旁组织之间BLACAT1表达差异;qRT-PCR检测人非小细胞肺癌细胞A549、HCC827、NCI-H1299、NCI-H23和正常肺上皮细胞BEAS-2B中BLACAT1的转录水平差异,筛选BLACAT1高表达非小细胞肺癌细胞系;CCK-8检测BLACAT1对非小细胞肺癌细胞增殖能力的影响;Transwell检测BLACAT1对非小细胞肺癌细胞迁移和侵袭能力的影响;starBase软件预测BLACAT1作用的miRNA,采用qRT-PCR验证敲低BLACAT1对预测miRNA表达的影响,筛选与BLACAT1相互作用的miRNA,双萤光素酶报告基因实验验证结果;CCK-8检测BLACAT1/miR-374b-5p对非小细胞肺癌细胞增殖能力的影响;Transwell检测BLACAT1/miR-374b-5p对非小细胞肺癌细胞迁移和侵袭能力的影响;Western印迹检测非小细胞肺癌细胞转移相关基因的蛋白表达水平。结果:肺腺癌及肺鳞癌组织中BLACAT1表达量显著高于癌旁组织;非小细胞肺癌细胞A549的BLACAT1表达量最高;敲低BLACAT1降低A549细胞活力、迁移和侵袭能力;BLACAT1作为海绵吸附miR-374b-5p;敲低BLACAT1增加miR-374b-5p的表达,抑制非小细胞肺癌细胞增殖、迁移和侵袭。结论:BLACAT1通过抑制miR-374b-5p促进非小细胞肺癌细胞增殖和转移。     

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。     

余甘子提取物调控LINC01772/miR-153对肺癌细胞A549生物学行为的影响

摘要 目的：探讨余甘子提取物对肺癌细胞A549增殖、迁移和侵袭的影响及机制。方法：体外培养A549细胞,分为对照组、不同剂量（低、中、高剂量）余甘子提取物组、si-NC组、si-LINC01772组、高剂量余甘子提取物+pcDNA组和高剂量余甘子提取物+pcDNA-LINC01772组,细胞计数试剂盒（CCK-8）法和克隆形成实验检测细胞增殖,划痕实验检测细胞迁移,嵌入式细胞共培养法（Transwell）检测细胞侵袭,免疫印迹法（Western Blot）检测细胞中上皮型钙黏蛋白（E-cadherin）和神经型钙黏蛋白（N-cadherin）蛋白表达水平,实时荧光定量PCR（RT-qPCR）检测LINC01772和miR-153表达水平。双荧光素酶报告基因实验验证LINC01772和miR-153调控关系。结果：与对照组相比,不同剂量余甘子提取物组A549细胞中LINC01772表达降低,且光密度值（OD值）、克隆形成数、迁移以及侵袭细胞数减少（P<0.05）,而miR-153含量与E-cadherin蛋白表达升高（P<0.05）,且呈剂量依赖性（P<0.05）。LINC01772在A549细胞中负调控miR-153表达。与si-NC组相比,si-LINC01772组A549细胞增殖,侵袭及迁移能力受到抑制（P<0.05）。与高剂量余甘子提取物+pcDNA组相比,高剂量余甘子提取物+pcDNA-LINC01772组A549细胞增殖,侵袭及迁移能力增强（P<0.05）。结论：余甘子提取物可能通过调控LINC01772/miR-153轴抑制肺癌细胞A549增殖、迁移和侵袭,其可能通过下调LINC01772进而上调miR-153表达发挥作用,具有开发为治疗肺癌药物的潜在价值。     

miR-195-5p在结直肠癌和肺癌细胞中的功能差异性研究

目的:分析miR-195-5p在结直肠癌和肺癌组织及相应肿瘤细胞中的表达差异和功能差异。方法:通过starBase数据库调取癌症基因组图谱(TCGA)中miR-195-5p表达数据,分析其在结直肠癌和肺癌组织中的表达差异;采用人结直肠癌细胞系SW620、小鼠结直肠癌细胞系MC38、人肺癌细胞系A549和小鼠肺癌细胞系344SQ进一步分析miR-195-5p在不同肿瘤细胞中的表达差异;采用CCK-8法检测miR-195-5p过表达对SW620和A549细胞增殖的影响;采用Transwell实验检测mi R-195-5p过表达对SW620和A549细胞侵袭与迁移能力的调控差异。结果:生物信息学分析结果显示miR-195-5p在结直肠癌组织中显著高表达,而在肺癌组织中的表达量却低于正常对照;与组织表达结果类似,结直肠癌细胞中miR-195-5p的表达量显著高于肺癌细胞;过表达miR-195-5p抑制人肺癌细胞A549的增殖、迁移与侵袭,而在人结直肠癌细胞SW620中结果却截然相反。结论:miR-195在不同类型的肿瘤中表达不同,功能也存在差异,不能简单地概括为一种抑癌因子或致癌因子,miR-195在肿瘤中的作用仍有待进一步研究。     

TGF-β1对卵巢癌细胞A2780增殖及迁移侵袭的影响

目的:探讨TGF-β1对卵巢癌细胞A2780增殖、迁移及侵袭能力的影响。方法:以体外培养的卵巢癌细胞A2780为研究对象,给予不同浓度(0、2、4…20 ng/m L)TGF-β1处理不同时间(12、24…72 h)。采用CCK-8法检测不同的浓度TGF-β1处理不同时间对卵巢癌细胞A2780增殖的影响。根据增殖实验结果选择合适的TGF-β1作用浓度及处理时间,采用细胞划痕实验测定细胞的迁移能力,Transwell实验检测细胞的侵袭及迁移能力。结果:相较于空白对照组,TGF-β1可以剂量和时间依赖性显著促进卵巢癌细胞A2780的增殖(P0.05)。细胞划痕实验结果显示TGF-β1处理组ΔS%/h明显高于空白对照组(P0.05);Transwell迁移实验结果显示:TGF-β1处理组OD570明显高于空白对照组,差异具有统计学意义(P0.05)。Transwell细胞侵袭实验结果显示:与空白对照组相比,TGF-β1处理组OD570明显升高(P0.05)。结论:TGF-β1可以明显促进卵巢癌细胞系A2780的增殖、迁移及侵袭能力,其促增殖效应呈剂量/时间依赖效应。     

D-甘露糖修饰黄芩苷阳离子脂质体的制备及其对肺癌A549细胞增殖的抑制作用

目的:制备一种D-甘露糖修饰的黄芩苷阳离子脂质体[Baicalin cationic liposome,BC-Lipo(+)],并考察其对肺癌A549细胞增殖的抑制效果。方法:用乙醇注入法制备BC-Lipo(+),并考察其药剂学性质;以肺癌A549细胞为模型,采用MTT法考察其对肿瘤细胞的抑制效果。结果:透射电镜下可见BC-Lipo(+)呈圆形或类圆形,平均粒径(111.3±2.7)nm,Zeta电位(9.6±0.3)m V,包封率(95.4±0.8)%;体外释药行为符合Ritger-Peppas方程(lnQ=0.3497lnt-1.6611,r=0.9924);A549细胞的增殖抑制率可达(88.3±5.7)%。结论:处方和制备工艺合理,BC-Lipo(+)包封率较高,粒径分布均匀,带一定的正电荷,具有明显的体外缓释特性,抑制肺癌A549细胞增殖效果显著,为深入研究肺靶向BC纳米脂质体制剂奠定了基础。     

MEKK3稳定表达细胞株的建立及其对A549细胞增殖的影响

目的 构建人MEKK3基因编码区序列（cDNA）的真核表达载体、建立其稳定表达细胞株并观察其对肺腺癌细胞增殖的影响.方法 从A549细胞中提取总RNA,应用RT-PCR扩增MEKK3 cDNA的全长序列后克隆入pcDNA3.1/hygro（＋）质粒中,构建成MEKK3基因的真核表达载体,然后转染入人肺腺癌A549细胞中,潮霉素筛选稳定转染克隆,通过MTT实验,研究转染MEKK3基因前后细胞增殖的变化.结果 重组载体经酶切鉴定和测序证实目的 基因正确无误,Western印迹检测结果显示MEKK3基因在A549细胞中具有良好的表达;荧光实时定量PCR结果表明MEKK3基因在其稳定转染的A549细胞克隆中表达上调,与空载体稳定转染及未转染细胞比较,差异具有统计学意义（P＜0.05）;MTT结果显示MEKK3表达上调的稳定克隆组,A549细胞的增殖活性显著增强（A570=0.876 1±0.074 5）,明显高于空载体稳定转染组（A570=0.582 8±0.070 3）及未转染亲代细胞组（A570=0.584 9±0.035 2）,差异具有统计学意义（P＜0.01）,而后两者之间差异无统计学意义（P＞0.05）.结论 MEKK3表达上调可导致肺腺癌细胞的增殖增强.     

MicroRNA‐144‐3p suppressed TGF‐β1‐induced lung cancer cell invasion and adhesion by regulating the Src–Akt–Erk pathway

Lung cancer remains a leading cause to cancer‐related death worldwide. The anti‐cancer ability of microRNA‐144‐3p has been reported in many cancer types. This study focused on the mechanisms underlying miR‐144‐3p in inhibiting lung cancer. The expression levels of miR‐144‐3p and steroid receptor coactivator (Src) in different lung cancer cell lines and those in bronchial epithelial cells (16HBE) were compared. miR‐144‐3p mimic and siSrc were transfected into A549 cells. Under the conditions of transforming growth factor‐β1 (TGF‐β1). Small interfering transfection or TGF‐β1 treatment, cell invasive and adhesive abilities were analyzed by Transwell and cell adhesion assays. miR‐144‐3p inhibitor and siSrc were co‐transfected into A549 cells and the changes in cell invasion and adhesion were detected. The activation of Src–protein kinase B–extracellular‐regulated protein kinases (Src–Akt–Erk) pathway was determined using Western blot. The downregulated miR‐144‐3p and upregulated Src were generally detected in lung cancer cell lines and were the most significant genes in A549 cells. Both miR‐144‐3p overexpression and Src inhibition could obviously inhibit the invasion and adhesion abilities of A549 cells in the presence or absence of the effects of TGF‐β1. The inhibition of Src could block the promotive effects of miR‐144‐3p inhibitor and TGF‐β1 on cell invasion and adhesion. Furthermore, we found that miR‐144‐3p could negatively regulate the phosphorylation levels of Akt and Erk. Our data indicated the essential role of Src in the mechanisms underlying TGF‐β1‐induced cell invasion and adhesion of lung cancer, and that miR‐144‐3p could effectively suppress TGF‐β1‐induced aggressive lung cancer cells by regulating Src expression.     

过表达miR-153非小细胞肺癌细胞稳转株的构建及鉴定

目的:构建过表达miR-153的非小细胞肺癌的稳转细胞株,为进一步探讨miR-153在肺癌发生发展中的作用奠定基础。方法:构建具有嘌呤霉素抗性的miR-153慢病毒载体;体外培养非小细胞肺癌细胞系SPC-A-1和A549,加入浓度梯度的嘌呤霉素溶液,筛选出最佳浓度;使用慢病毒转染细胞株,并在转染72 h后用荧光显微镜检测绿色荧光蛋白(EGFP)的表达,评价转染效率;体外实验使用PCR检测miR-153在稳转株的表达;稳转株移植裸鼠体内成瘤,取出瘤体后检测瘤体内EGFP和miR-153的表达。结果:完成过表达miR-153慢病毒载体及阴性对照载体的构建;确定嘌呤霉素最佳筛选浓度:在SPC-A-1细胞中的浓度为2.0 g/mL,A549细胞中的浓度为3.0 g/mL;目的基因miR-153被慢病毒成功导入SPC-A-1细胞和A549细胞中,荧光显微镜下能直接观察到EGFP。转染miR-153组和阴性对照组的PCR实验结果显示:在SPC-A-1细胞中,miR-153的表达量为92.9±20.6,明显高于阴性对照组(P=0.016);在A549细胞中,miR-153的表达量为2624.6±153.4,显著高于阴性对照组(P0.001)。稳转株能在裸鼠体内形成移植瘤,瘤体内明显有EGFP的表达;与阴性对照组的瘤体相比,移植瘤组miR-153的表达量为显著上调(P=0.048)。结论:成功构建过表达miR-153的非小细胞肺癌的稳转细胞株。     

Akt2 and nucleophosmin/B23 function as an oncogenic unit in human lung cancer cells

The signaling network of protein kinase B(PKB)/Akt has been implicated in survival of lung cancer cells. However, understanding the relative contribution of the different isoform of Akt network is nontrival. Here, we report that Akt2 is highly expressed in human lung adenocarcinoma cell line A549 cells. Suppression of Akt2 expression in A549 cells results in notable inhibition of cell poliferation, soft agar growth, and invasion, accompanying by a decrease of nucleophosmin/B23 protein. Overexpression of Akt1 restores cancerous growth of A549 cells in B23-knockdown (KD) cells while Akt2 overexpression did not restore proliferating potential in cells with downregulated B23, thus suggesting Akt2 requires B23 to drive proliferation of lung cancer cell. Loss of functional Akt2 and B23 has similar defects on cell proliferation, apoptotic resistance and cell cycle regulation, while loss of Akt1 has less defects on cell proliferation, survial and cell cycle progression in A549 cells. Moreover, overexpression of B23 rescues the proliferative block induced as a consequence of loss of Akt2. Thus our data suggest that Akt2/B23 functions as an oncogenic unit to drive tumorigenesis of A549 lung cancer cells.     

Expression of periostin in the serum of NSCLC and its function on proliferation and migration of human lung adenocarcinoma cell line (A549) in vitro

Periostin is over expressed in many epithelial malignant cancers, including lung cancer, breast cancer, ovarian cancer and colon cancer. It is related with the progression and migration of breast and ovarian cancer cells in vitro. The aim of this study was to investigate the serum level of periostin in non-small cell lung cancer (NSCLC) and its relationship with established biological and prognostic factors by enzyme-linked-immunosorbent serologic assay. We also observe the function of periostin on the proliferation and migration of human lung adenocarcinoma cell line (A549) and discuss the mechanism. The mean value for serum periostin (POSTN) was elevated in NSCLC patients (242.84 ± 5.33 pg/ml) compared to the normal healthy volunteers (215.66 ± 11.67 pg/ml) (p = 0.030). The serum level of periostin of NSCLC patients had no connection with gender, age, pathological type, TNM stage, lymph node status, tumor size and invasiveness. We constructed a plasmid named pEGFP-N1/POSTN expressing full-length human periostin. Transfecting the plasmid to A549 cells and periostin was efficiently expressed in transfected A549 cells. Our data showed that periostin could promote the proliferation and migration of A549 cells by inducing vimentin and N-cadherin expression and downregulating E-cadherin expression. These results strongly suggest that periostin is a novel molecular which play an important role during the progression and development of NSCLC.     

bFGF 诱导肺腺癌细胞系A549 上皮间质转化

目的:探讨上皮间质转化(epithelial-mesenchymal transition,EMT)过程在肺癌侵袭转移中的作用。方法:体外培养A549细胞,以bFGF(10ng/ml)进行干预后,倒置相差显微镜观察细胞形态学变化;间接免疫荧光观察上皮细胞标志物E-cadherin和间质细胞标志物vimentin蛋白表达的变化;采用细胞划痕试验检测bFGF对A549细胞迁移能力的影响;采用transwell小室试验检测bFGF对A549细胞侵袭能力的影响。结果:bFGF(10ng/ml)干预后,在倒置相差显微镜下观察,A549细胞形态变成了梭形,形态如同成纤维细胞。间接免疫荧光显示A549细胞E-cadherin表达随时间延长逐渐减弱,而vimentin表达逐渐增强。细胞划痕试验显示,bFGF干预后细胞迁移能力提高。Transwell小室试验显示,bFGF干预后细胞侵袭能力提高。结论:bFGF在体外诱导肺腺癌细胞系A549细胞发生上皮间质转化,上皮间质转化是肺癌侵袭转移的重要机制之一。     

CDK4基因沉默对非小细胞肺癌A549 增殖和代谢的影响

目的:通过特异性小干扰RNA(small interfering RNA,si RNA),使CDK4基因沉默,探讨该基因沉默对肺癌A549细胞增殖和代谢的影响及其可能的作用机制。方法:将靶向CDK4小干扰RNA(si RNA-CDK4)和阴性对照干扰片段(si RNA-control)成功转染A549细胞后,利用实时荧光定量PCR和蛋白质免疫印迹法分别检测CDK4在m RNA和蛋白水平的变化;细胞计数法、CCK-8法和软琼脂糖克隆形成实验检测A549增殖的变化和克隆形成能力;FCM法检测A549细胞的细胞周期;18F-FDG摄取实验、乳酸检测试剂盒及海马技术检测A549细胞中葡萄糖、乳酸的量及氧耗的变化;利用RT-PCR检测CDK4基因沉默后A549细胞中糖代谢相关酶m RNA水平的变化。结果:将靶向CDK4小干扰RNA(si RNA-CDK4)转染A549细胞后,可明显抑制CDK4的m RNA和蛋白表达(P0.001,P0.01)。CDK4蛋白抑制后,细胞增殖在48、72和96 h均明显降低(P值均0.05),G1期细胞比例明显增多,S期细胞比例明显减少(P值均0.05);18F-FDG摄取量下降(42.21±1.90)%(P0.05),乳酸的生成量减少(29.39±5.35)%(P0.05),而细胞的基础耗氧量增加(67.17±3.58)%(P0.01);糖酵解相关酶PFKFB3、PKM2、LDHA在m RNA水平均明显减低(P0.001,P0.01,P0.001)。结论:抑制CDK4表达可明显降低糖酵解水平,并增加耗氧量;同时可引起细胞周期阻滞,抑制肿瘤细胞增殖。其机制可能与CDK4直接或间接调节糖酵解相关酶的表达有关。     

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.