ABCE1基因沉默对人肝癌SMMC-7721细胞增殖和迁移能力的影响

目的探讨ATP结合盒转运FE1ABCE1基因对细胞的生长、细胞周期及肿瘤迁移等方面的作用。方法设计及合成ABCE1的siRNA序列,Lipofectamine TM2000转染SMMC-7721细胞。通过RT-PCR、Western印迹检测ABCE1在干扰后的mRNA和蛋白的表达情况,通过流式细胞仪检测细胞周期。通过CCK-8增殖实验、划痕愈合实验、细胞侵袭实验评价沉默ABCE1基因对人肝癌SMMC-7721细胞增殖、迁移以及侵袭能力的影响。结果 ABCE1 mRNA和蛋白表达,实验组较对照组和空白组显著降低(P<0.05)。实验组细胞的生长速度明显减慢,细胞周期被阻滞在G0/G1期,S期细胞数减少(P<0.05)。CCK-8增殖实验显示,与对照组和空白组相比,实验组MMC-7721细胞的增殖受到明显抑制(P<0.05)。划痕愈合实验显示,实验组迁移能力显著下降(P<0.05)。Transwell小室法示,实验组MMC-7721细胞的侵袭能力显著下降(P<0.05)。结论特异性干扰ABCE1基因表达可抑制人肝癌SMMC-7721细胞的迁移能力,并抑制肿瘤细胞增殖,因此,ABCE1的siRNA序列可能成为治疗肝癌的有效靶点。     

siRNA干扰沉默EZH2基因对人肝癌HepG2细胞增殖的影响

目的探讨小分子RNA(siRNA)干扰沉默靶基因EZH2对人肝癌HepG2细胞增殖的影响。方法取对数生长期的HepG2细胞,分为转染组、阴性对照组及空白对照组,转染组与阴性对照组按照Lipofectamine2000使用说明分别瞬时转染EZH2 siRNA、荧光物FAM,对照组不予任何干预。分别采用MTT法检测细胞增殖活性、流式细胞仪检测细胞凋亡率及周期;qRealtime-PCR和Western blot方法检测EZH2 mRNA和蛋白表达。结果与阴性对照组相比,转染组细胞增殖明显受抑;与阴性对照组及空白对照组比较,转染组细胞凋亡率明显升高,G0/G1期细胞明显增多,S期明显细胞减少;转染组EZH2 mRNA和蛋白表达明显下调,P均<0.05。结论 EZH2 siRNA可抑制人肝癌细胞增殖活性,是一种潜在基因治疗新方法。     

KPNA2基因沉默对人肝癌细胞株SMMC7721和Bel7404增殖和侵袭能力的影响

目的观察核转运蛋白基因α2(Karyopherinα-2,KPNA2)基因沉默对人肝癌细胞株SMMC7721和Bel7404增殖以及侵袭能力的影响。方法将KPNA2 siRNA干扰质粒用LipofectaminTM 2000方法瞬时转染人肝癌细胞株SMMC7721和Bel7404,转染后48 h应用蛋白质印迹法检测转染细胞中KPNA2蛋白表达。采用MTT法检测基因沉默细胞增殖能力,采用Transwell法检测基因沉默细胞侵袭能力。结果 SMMC7721细胞株对照组mRNA为1.02±0.13,高于siRNA转染组的0.37±0.07(t=10.78,P0.01);肝癌Bel7404细胞株对照组mRNA为1.05±0.17,高于siRNA转染组的0.36±0.06(t=9.38,P0.01)。肝癌SMMC7721细胞株对照组蛋白定量值为0.96±0.10,高于转染组的0.42±0.05(t=11.83,P0.01);肝癌Bel7404细胞株对照组蛋白定量值为0.93±0.09,高于转染组的0.48±0.06(t=10.19,P0.01)。SMMC7721和Bel7404细胞株在24、48和72 h时对照组增殖能力高于转染组,且差异有统计学意义(P0.05)。SMMC7721细胞株对照组侵袭能力值为126.20±21.61,高于siRNA转染组的51.13±10.2(t=7.68,P0.01);肝癌Bel7404细胞株对照组侵袭能力值为125.124±8.04,高于siRNA转染组的55.20±18.54(t=8.48,P0.01)。结论KPNA2基因沉默可以调节人肝癌细胞株SMMC7721和Bel7404的增殖能力和侵袭能力。     

三氧化二砷对人肝癌SMMC-7721细胞增殖、迁移及侵袭能力的影响

目的 探讨三氧化二砷(As2O3)对人肝癌SMMC-7721细胞增殖、迁移和侵袭能力的影响及其分子机制.方法 利用MTS/PMS法检测As2O3对SMMC-7721细胞增殖的影响;划痕愈合和侵袭实验检测As2O3对SMMC-7721细胞迁移与侵袭能力的影响;实时定量PCR、Western印迹检测As2O3作用SMMC-7721细胞后MMP-9的表达.结果 2.0 μmol/L的As2O3对肿瘤细胞增殖有抑制作用;划痕实验结果显示,2.0μmol/LAs2O3处理SMMC-7721细胞12和24 h后,较未处理组划痕距离明显增加(P＜0.05),表明As2O3可抑制SMMC-7721细胞迁移.Transwell实验结果显示,2.0μmol/LAs2O3处理SMMC-7721细胞12h和24 h后,穿膜细胞数较未处理组明显减少(P＜0.05),表明As2O3可抑制SMMC-7721细胞侵袭能力.实时定量PCR和Western印迹结果显示,以2.0μmol/L As2O3处理SMMC-7721细胞后,MMP-9 mRNA和蛋白表达均明显下调(P＜0.05).结论 As2O3可通过抑制肿瘤细胞增殖、迁移及侵袭,抑制肿瘤的转移.     

VEGF基因沉默对肝癌HepG2细胞侵袭和迁移的影响

目的观察VEGF基因沉默对人肝癌细胞株HepG2迁移和侵袭的影响。方法采用siRNA技术沉默HepG2细胞内血管内皮细胞生长因子(VEGF)基因。体外成功构建针对VEGF的3种siRNA表达载体和1个阴性对照,分别命名为pGenesil-1-VEGF-shRNA-1、2、3和pGenesil-1-VEGF-shRNA-scramble。Lipofectamine 2000介导转染HepG2,用RT-PCR筛选出沉默效果最好的siRNA片断(pGenesil-1-VEGF-shRNA-2),将其重组质粒转染HepG2(观察组),以空质粒细胞(空载组)和空白细胞(空白组)作为对照。采用细胞创伤愈合试验、Transwell小室体外侵袭试验分别检测三组细胞迁移、侵袭能力。结果细胞创伤愈合试验显示,观察组细胞迁移速度为(3.02±0.03)μm/h,显著慢于空载组的(8.67±0.02)μm/h和空白组的(8.78±0.03)μm/h,P均<0.05;细胞侵袭试验显示,观察组穿膜细胞数为(14.0±1.3)个,显著低于空载组的(35.0±2.3)个和空白组的(36.0±2.5)个,P均<0.05。结论 VEGF基因沉默可抑制肝癌细胞株HepG2的迁移和侵袭能力。     

RNA干扰沉默Cyclin D1基因对胰腺癌AsPC-1细胞增殖和凋亡的影响

目的探讨以细胞周期蛋白（Cyclin）D1为靶基因的RNA干扰对胰腺癌AsPC-1细胞增殖和凋亡的影响,为胰腺癌的靶向治疗提供依据。方法用含有10％FBS的DMEM培养液在37℃、5％CO2培养箱中常规培养AsPC-1细胞,至对数生长期后接种于96孔培养板中,随机分为实验组、阴性对照组、空白对照组,并采用Lipo-fectamine^TM 2000脂质体分别转染Cyclin D1-小干扰RNA（siRNA）、阴性对照siRNA、脂质体,48h时收集细胞。应用荧光定量PCR法和Western blot法分别检测细胞中Cyclin D1 mRNA和蛋白表达水平,MTT法检测细胞体外增殖活力,流式细胞仪检测细胞周期分布及凋亡率（AI）。结果与空白对照组和阴性对照组相比,实验组Cyclin D1 mRNA和蛋白表达均明显下调,细胞生长速度明显减慢,G0／G1细胞比例显著增大、S期细胞比例则明显降低、AI显著升高（P均〈0．01）。结论Cyclin D1-siRNA能通过沉默靶基因表达抑制AsPC-1细胞生长、改变细胞周期分布、诱导细胞凋亡,可作为胰腺癌基因治疗的一个有效靶点。     

siRNA抑制survivin基因及其对人肝癌细胞株HepG2细胞凋亡的影响

目的观察特异小干扰RNA（small interfering RNA,siRNA）抑制survivin基因表达对人肝癌细胞株HepG2细胞凋亡的影响。方法构建survivin-siRNA真核表达载体,利用脂质体转染人肝癌HepG2细胞,采用反转录聚合酶链反应（RT-PCR）技术检测survivin基因mRNA表达水平。针对转染后不同的时间点采用四甲基偶氮唑蓝（MTT）法检测各组细胞的增殖以及HepG2细胞的凋亡情况。结果构建的survivin-siRNA转染组survivin蛋白表达较对照组明显下调,差异有显著性（P〈0.01）,其增殖能力较对照组显著下降（P〈0.001）;而阳性对照组及未转染组对survivin表达及mRNA抑制作用不明显（P=0.219）。结论所构建的针对人survivin-siRNA可显著抑制survivin的表达及HepG2细胞凋亡。     

黄芪多糖对肝癌HepG2细胞的抑制作用及其机制

目的 研究黄芪多糖(APS)和5-氟尿嘧啶(5-fu)联合使用对肝癌HepG2细胞的生长抑制及其作用机制.方法 用RPMI1640培养液对低分化人肝癌细胞株HepG2进行传代培养,取对数生长期细胞, 分为5组:A组:对照组,不含药物,使用同体积的磷酸盐缓冲液(PBS);B组:APS组,只给予100 μg/mlAPS;C组:5-fu组,只给予100 μg/ml 5-fu;D组:5-fu+低浓度APS组,给予100 μg/ml 5-fu+100 μg/ml APS;E组:5-fu+高浓度APS组,给予100 μg/ml 5-fu+200 μg/ml APS.用噻唑蓝(MTT)法观察APS及5-fu对HepG2细胞增殖的影响;用流式细胞术方法测药物作用后细胞周期变化和细胞凋亡;western-blot检测凋亡相关蛋白表达.结果 APS和5-fu联合使用可抑制HepG2细胞的增殖,效应呈浓度和时间依赖性;APS和5-fu联合使用阻滞HepG2细胞周期于G1期;并可诱导HepG2细胞凋亡;APS和5-fu联合使用,可明显增高肝癌HepG2细胞中caspase-3、caspase-9蛋白的表达,同时检测到抑凋亡蛋白Bcl-2表达显著降低.在只使用5-fu的实验组细胞中均未检测到上述变化.结论 APS和5-fu联合使用能抑制肝癌HepG2细胞株的增殖,其机制之一是影响细胞周期使之阻滞于G1期,激活了细胞凋亡系统,从而诱导细胞凋亡.     

花姜酮对人肝癌SMMC-7721细胞侵袭及CXCR4表达的影响

目的研究花姜酮对人肝癌SMMC-7721细胞生长侵袭能力的影响及对CXCR4 mRNA和蛋白表达的影响,探讨花姜酮抗肝癌侵袭可能的作用机制。方法分别应用花姜酮10μmol/L、20μmol/L处理人肝癌细胞,采用Transwell小室检测肝癌细胞的侵袭能力,RT-PCR、Western blotting实验检测CXCR4 mRNA及蛋白表达的变化。结果花姜酮处理人肝癌细胞48 h后,对照组细胞透膜数为(56.8±7.8)个/视野,10μmol/L组透膜数为(41.4±4.8)个/视野,20μmol/L组透膜数为(23.2±5.6)个/视野,随花姜酮浓度增加,细胞侵袭人工基底膜的能力显著降低(P<0.05),RT-PCR及Western blotting结果显示CXCR4 mRNA及蛋白表达随花姜酮浓度的增加而降低(P<0.05)。结论花姜酮可能通过降低CXCR4的表达抑制人肝癌SMMC-7721细胞的生长和侵袭能力。     

RNAi沉默Sp3基因对肝癌HepG2细胞增殖的影响

目的:采用基因沉默和慢病毒转染技术,沉默人肝癌细胞HepG2中特异蛋白3(specificity protein 3,Sp3)的表达,观察沉默Sp3基因后的肝细胞的增殖能力变化.方法:采用Sp3-siRNA慢病毒转染人肝癌细胞HepG2,通过免疫印迹法和PCR技术检测Sp3的表达以验证转染效果,通过MTT检测细胞生长曲线和流式细胞技术测定细胞周期.结果:Western blot实验表明,实验组的Sp3表达量明显少于空白组和阴性对照组(0.37±0.08 vs 0.83±0.17,0.66±0.13,F=8.442,均P<0.05).RT-PCR也得到相同的结果(0.47±0.05 vs 0.74±0.08,0.70±0.16,F=7.322,均P<0.05).MTT实验结果显示,与空白对照和阴性对照组相比,实验组细胞在48、72和96h时的增殖明显受到抑制(0.28±0.18 vs 0.34±0.19,0.35±0.07,F=3.888;0.57±0.11 vs 0.84±0.05,0.74±0.08,F=12.721;0.72±18.1 vs 0.98±0.05,0.93±0.9,F=6.342,均P<0.05).流式细胞术结果显示实验组细胞主要分布在G1期.结论:RNAi沉默Sp3基因导致人肝癌HepG2细胞体外增殖能力下降.     

Survivin antisense compound inhibits proliferation and promotes apoptosis in liver cancer cells

AIM: To evaluate the effects of survivin on cell proliferation and apoptosis in liver cancer. METHODS: MTT assay was used to generate and optimize phosphorothioate antisense oligonucleotides (ODNs)-LipofectamineTM2000 (LiP) compound by varying ODNs (μg): LiP (μL) ratios from 1:0.5 to 1:5. Then, liver cancer cells (HepG2) were transfected with the compound. By using RT-PCR and Western blot, the expression levels of survivin mRNA and proteins were detected in HepG2 cells treated with antisense compounds (ODNs:LiP=1:4), and compared with those treated with sense compounds (1:4) as control. MTT assay was applied to the determination of cell proliferation in HepG2 cells. Active caspase-3 was evaluated by flow cytometric analysis. The morphological changes were assessed by electron microscopy. Laser scanning confocal microscopy was performed to detect the subcellular localization of survivin proteins in treated and untreated cells. RESULTS: Antisense compounds (1:4) down-regulated survivin expression (mRNA and protein) in a dose-dependent manner with an IC50 of 250 nmol/L. Its maximum effect was achieved at a concentration of 500 nmol/L, at which mRNA and protein levels were down-regulated by 80%. The similar results were found in MTT assay. Antisense compound (l:4)-treated cells revealed increased caspase-3-like protease activity compared with untreated cells. Untreated cells as control were primarily negative for the presence of active-caspase-3. As shown by transmission electron microscopy, treated cells with antisense compounds (1:4) resulted in morphological changes such as blebbing and loss of microvilli, vacuolization in the cytoplasm, condensation of the cytoplasm and nuclei, and fragmented chromatin. Immunofluorescence analysis confirmed the presence of survivin protein pool inside the cytoplasm in untreated cells. Labeled-FITC immunofluorescence staining of survivin clearly showed that survivin was distributed mainly in a spotted form inside the cytoplasm. Whereas cells treated with antisense compounds were rare and weak inside the cytoplasm. CONCLUSION: Down-regulation of survivin expression induced by the antisense compounds reduces tumor growth potential, promotes apoptosis and affects the localization of survivin proteins in HepG2 cells. Furthermore, survivin protein is a key molecule associated with proliferation and apoptosis, and antisense oligonucleotides targeting survivin have a bright prospect in the therapy of liver cancer.     

Overexpression of cyclooxygenase-2 in human HepG2, Bel-7402 and SMMC-7721 hepatoma cell lines and mechanism of cyclooxygenase-2 selective inhibitor celecoxib-induced cell growth inhibition and apoptosis

AIM: To investigate the cyclooxygenase-2 (COX-2) expression level in human HepG2, Bel-7402 and SMMC-7721 hepatoma cell lines and the molecular mechanism of COX-2 selective inhibitor celecoxib-induced cell growth inhibition and cell apoptosis. METHODS: Hepatoma cells were cultured and treated with celecoxib. Cell In situ hybridization (ISH) and immunocytochemistry were used to detect COX-2 mRNA and protein expression. Proliferating cell nuclear antigen and phosphorylated Akt were also detected by immunocytochemistry assay. Cell growth rates were assessed by 3-(4, 5-dimethylthiazol-2-yl-2, 5-diphenylte-trazolium (MTT) bromide colorimetric assay. Celecoxib-induced cell apoptosis was measured by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and flow cytometry (FCM). The phosphorylated Akt and activated fragments of caspase-9, caspase-3 were examined by Western blotting analysis. RESULTS: Increased COX-2 mRNA and protein expression were detected in all three hepatoma cell lines. Celecoxib could significantly inhibit cell growth and the inhibitory effect was in a dose- and time-dependent manner evidenced by MTT assays and morphological changes. The apoptotic index measured by TUNEL increased correspondingly with the increased concentration of celecoxib and the reaction time. With 50 μmol/L celecoxib treatment for 24 h, the apoptotic index of HepG2, BEL-7402 and SMMC-7721 cells was 25.01±3.08%, 26.40±3.05%, and 30.60±2.89%, respectively. Western blotting analysis showed remarkable activation of caspase-9, caspase-3 and dephosphorylation of Akt (Thr308). Immunocytochemistry also showed the reduction of PCNA expression and phosphorylation Akt (Thr308) after treatment with celecoxib. CONCLUSION: COX-2 mRNA and protein overexpression in HepG2, Bel-7402 and SMMC-7721 cell lines correlate with the increased cell growth rate. Celecoxib can inhibit proliferation and induce apoptosis of hepatoma cell strains in a dose- and time-dependent manner.     

Effects of Pinus massoniana bark extract on cell proliferation and apoptosis of human hepatoma BEL-7402 cells

AIM:To study the effects of Pinus massoniana bark extract (PMBE) on cell proliferation and apoptosis of human hepatoma BEL-7402 cells and to elucidate its molecular mechanism. METHODS:BEL-7402 cells were incubated with various concentrations (20-200 ug/mL) of PMBE for different periods of time. After 48 h, cell proliferation was determined by 3-(4,5-dimethyl-thiazolyl-2)-2,5-diphenyl tetrazolium bromide (MTT) assay. Apoptosis was evaluated by morphological observation, agarose gel electrophoresis, and flow cytometry analysis. Possible molecular mechanisms were primarily explored through immunohistochemical staining. RESULTS:PMBE (20-200 ug/mL) significantly suppressed BEL-7402 cell proliferation in a time-and dose-dependent manner. After treatment of BEL-7402 cells with 160 ug/mL PMBE for 24, 48, or 72 h, a typical apoptotic "DNA ladder"was observed using agarose gel electrophoresis. Nuclear condensation and boundary aggregation or split, apoptotic bodies were seen by fluorescence and electron microscopy. Sub-G_1 curves were displayed by flow cytometry analysis. PMBE decreased the expression levels of Bcl-2 protein in a time-dependent manner after treatment of cells with 160 ug/mL PMBE. CONCLUSION:PMBE suppresses proliferation of BEL-7402 cells in a time-and dose-dependent manner and induces cell apoptosis by possibly downregulating the expression of the bcl-2 gene.     

亚砷酸对肝癌BEL-7402细胞增殖、凋亡及其Bcl-2表达的影响

目的探讨亚砷酸（AA）对人肝癌BEL-7402细胞增殖、凋亡及其Bcl-2表达的影响。方法采用MTT比色法检测从作用后的BEL-7402细胞增殖抑制率,流式细胞术检测BEL-7402细胞周期及凋亡细胞,HE染色法观察凋亡细胞的形态,RT-PCR检测BEL．7402细胞的Bcl-2 mRNA,免疫组化法检测细胞的Bcl-2蛋白。结果1．0—8．0μmol／L的AA可使BEL-7402细胞增殖抑制率上升,能诱导BEL-7402细胞凋亡并阻滞细胞周期于S、G2／M期,呈剂量依赖性;8．0μmol／L的AA作用BEL-7402细胞48h后,细胞呈现明显的凋亡形态改变,其Bcl-2 mRNA及蛋白表达明显减弱。结论AA体外有抑制BEL-7402细胞增殖及诱导凋亡的作用,且呈时间、剂量依赖性,其作用机制可能与降低其Bcl-2表达有关。     

牛蒡子苷元对肝癌侵袭转移的影响

目的:研究牛蒡子苷元(arctigenin,ARG)对肿瘤黏附、侵袭、转移的影响.方法:体外实验分别采用MTT法、Transwell 法检测ARG对SMMC-7721细胞黏附、侵袭和转移的影响;体内实验采用裸鼠肺转移瘤模型,检测ARG对SMMC-7721细胞肺转移的影响.结果:与空白对照组相比,ARG作用后SMMC-7...     

miRNA沉默缺氧诱导因子1α基因对HepG2细胞增殖的抑制作用

目的 探讨以miRNA沉默缺氧诱导因子1 α(HIF-1 α)基因,观察其对肝癌细胞株(HepG2细胞)增殖的抑制作用.方法 构建靶向HIF-1 α基因miRNA干扰载体,转染HepG2细胞,以定量PCR和Western blot分析靶基因和蛋白的表达;构建含缺氧反应元件双荧光素酶报告基因检测转染后相对光单位值;酶联免疫吸附法定量检测血管内皮生长因子和血管生成素2的表达;细胞凋亡及增殖周期以流式细胞仪和膜联蛋白/碘化丙啶(V-FITC/PI)双重染色法分析.采用t检验和两因素方差分析及q或q'检验分析计量资料.结果 HepG2细胞在转染HIF-1 αmiRNA后72 h,HIF-1 α在转录和翻译水平上分别下降87%和56%双荧光素酶报告基因减少46%,血管内皮生长因子和血管生成素2分别减少54%和36%;癌细胞凋亡率为22.46%±0.61%(P＜0.01),G1和S期比例分别为61.49%±1.12%和22.40%±0.58%;联合阿霉素处理后,凋亡率增至36.99%±0.88%,G1、S期比例分别为65.68%±0.91%和19.47%±1.34%.结论 HIF-1 α miRNA可抑制HIF-1 α基因表达,联合阿霉素有效调控肝癌细胞周期,促进凋亡、抑制增殖.

Abstract：

Objective To investigate the effect of miRNA silencing HIF-1 α gene on the proliferation of HepG2 cells. Methods The eukaryotic expression plasmids of HIF- 1α miRNA and report gene containing hypoxia-reponse element were constructed and trasnfected into HepG2 cells. The expressions of HIF-1 α gene and protein were determined by real time-PCR and Western blotting. The expressions of HIF1 α, vascular endothelial growth factor (VEGF) and angiopoietin-2 (Ang-2) were quantitatively detected by ELISA. The alterations of cell cycles and apoptosis rate were quantitatively measured by flow cytometry and Annexin V-FITC/PI double dyeing assay. Results 72 h after transfection the downregulations of HIF-1 α mRNA and protein were 87% and 56% respectively, and the decrease of target gene was 46% in the report gene, 54% in VEGF and 36% in Ang-2, respectively. The apoptotic ratio of HepG2 cells was 22.46 ± 0.61%(P ＜ 0.01). The cell cycle changed greatly at the ratio of G1 (61.49 ± 1.12%) and S (22.40 ± 0.58%, P ＜0.01). After being combined with doxorubicin, the apoptotic ratio increased to 36.99 ± 0.88% and the ratios of G1 and S phases were upregulated to 65.68 ± 0.91% and 19.47 ± 1.34% respectively. Conclusion HIF-1α miRNA or / and doxorubicin can regulate the growth cycles of HepG2 cells, promote the cell apoptotosis and inhibit the cell proliferation.     

尼古丁对人A549细胞增殖、侵袭和迁移能力的影响

目的 观察烟草烟雾中的主要有害成分尼古丁对人A549细胞增殖、迁移与侵袭能力的影响,探讨尼古丁致病的可能机制.方法 以一定浓度尼古丁刺激体外培养的人A549细胞,应用CCK-8法、Transwell法和细胞划痕实验分别检测A549细胞的增殖、侵袭及迁移能力.Western blot检测α7烟碱型乙酰胆碱受体(α7 nAChR)、血管内皮生长因子(VEGF)和基质金属蛋白酶2(MMP-2)蛋白的表达.结果 与空白对照组比较,10-6 mol/L尼古丁处理A549细胞后,促进人A549细胞增殖(t=7.920,P<0.05);使穿过基质胶的细胞数增多,侵袭能力增强(t=5.298,P<0.05);使细胞迁移率增加,迁移能力增强(P<0.05).与空白对照组比较,10-6 M尼古丁处理A549细胞24 h后,α7 nAChR、VEGF和MMP-2蛋白表达上调,差异有统计学意义(t值分别为5.800、4.074、6.851,P值均<0.05).结论 尼古丁通过其特异性受体α7 nAChR可增强人A549细胞的增殖、侵袭和迁移能力,其机制可能与VEGF和MMP-2蛋白表达上调有关.     

TM7SF4对人甲状腺乳头状癌细胞IHH-4增殖、凋亡和侵袭的作用研究

目的 探讨树突表达特异性7跨膜蛋白(TM7SF4)的低表达对人甲状腺乳头状癌细胞IHH-4增殖、凋亡和侵袭的作用及其相关机制.方法 选取甲状腺乳头状癌患者的手术标本(癌组织及癌旁组织)及甲状腺乳头状癌细胞系IHH-4为对象.qRT-PCR法检测病理组织和细胞系IHH-4中TM7SF4的mRNA表达量.分别用MTT法、流式细胞分析和Transwell法检测TM7SF4表达量对IHH-4细胞增殖、凋亡和侵袭的影响.Western印迹检测IHH-4细胞中磷酸化与非磷酸化磷脂酰肌醇3激酶(PI3K)、蛋白激酶B(Akt)、哺乳动物雷帕酶素靶蛋白(mTOR)的表达.结果 与癌旁组织相比,甲状腺癌组织中TM7SF4的mRNA表达水平显著升高(t=52.31,P＜0.05).与正常甲状腺细胞系Nthy-ori 3-1相比,IHH-4细胞系中TM7SF4的表达水平也显著上升(t=34.35,P＜0.05).与对照组细胞相比,沉默TM7SF4的表达后,可诱导IHH-4细胞凋亡,而细胞增殖和侵袭能力受到显著抑制(F=8.32,7.55,846.40;P均＜0.05).此外,沉默TM7SF4的表达后可显著降低磷酸化PI3K、磷酸化Akt、磷酸化mTORmRNA及蛋白的表达(F=1014.88,1121.29,985.22,720.14,854.63,4 563.12;P均＜0.05).结论 低表达的TM7SF4可能通过下调PI3K/Akt/mTOR通路而抑制IHH-4细胞增殖、诱导凋亡并抑制侵袭.