siRNA沉默Bmi-1基因对人肝癌细胞株MHCC97-H侵袭迁移能力的影响

目的:探讨RNA干扰技术沉默Bmi-1基因表达后,对人肝癌细胞株MHCC97-H侵袭迁移能力的影响.方法:设计并合成针对Bmi-1基因序列特异性的双链小干扰RNA(Bmi-1-siRNA),转染高转移性人肝癌细胞株MHCC97-H,用流式细胞仪观察转染效率,荧光实时定量PCR和Westernblot检测Bmi-1基因的mRNA和蛋白表达水平;通过体外Transwell小室基质侵袭和迁移实验,观察Bmi-1表达沉默后对人肝癌细胞株MHCC97-H侵袭和迁移能力的影响.结果:将针对Bmi-1基因序列特异性的小干扰RNA(Bmi-1-siRNA)转染高转移性人肝癌细胞株MHCC97-H后,流式细胞仪显示,转染效率可达到91%.与空白组、对照siRNA组相比,实验组Bmi-1-siRNA能有效抑制MHCC97-H细胞中Bmi-1基因的mRNA(F=56.199,P<0.05)和蛋白表达水平.通过Transwell小室基质侵袭和迁移实验,我们分析了不同组细胞的侵袭迁移能力.结果发现,与空白组、对照siRNA组相比,Bmi-1-siRNA转染的MHCC97-H细胞穿透能力明显降低(F=186.66,12.746,P<0....     

siRNA沉默NHE1基因对MHCC97-H肝癌细胞侵袭迁移的影响

目的:探讨RNA干扰沉默NHE1基因后对人肝癌细胞株MHCC97-H细胞侵袭迁移的影响,方法:应用NHE1基因小干扰RNA(smallinterfering RNA,siRNA)转染人肝癌细胞株MHCC97-H细胞,同时设立空白对照组和无关对照组.转染成功后采用RT-PCR和Western blot分别从基因和蛋白水平...     

TROP-2基因小干扰RNA转染对前列腺癌细胞黏附、迁移和侵袭的影响

目的观察肿瘤相关钙信号转导蛋白-2(TROP-2)基因小干扰RNA(siRNA)转染对前列腺癌细胞黏附、迁移和侵袭的影响。方法以TROP-2基因siRNA转染人前列腺癌PC-3细胞后,分别用实时荧光定量PCR和Western blot法检测细胞TROP-2 mRNA和蛋白,用MTT法检测PC-3细胞吸光度值(以此判断细胞黏附力),以Tr-answell小室实验观察细胞的迁移、侵袭情况。结果与空载对照组相比,TROP-2 siRNA组TROP-2 mRNA的表达明显下降(P均<0.01)并呈浓度和时间依赖性(P均<0.01);与空白对照组及空载对照组相比,TROP-2 siRNA组TROP-2蛋白的表达明显下降(P均<0.01)并呈浓度和时间依赖性(P均<0.01);与空白对照组相比,TROP-2 siR-NA组细胞黏附力下降(P<0.01)并呈浓度、时间依赖性(P均<0.05);与空白对照组及空载对照组相比,TROP-2siRNA组细胞迁移、侵袭数明显减少(P均<0.01)并呈浓度依赖性(P均<0.01)。结论 TROP-2基因siRNA转染可抑制前列腺癌PC-3细胞黏附、迁移和侵袭。     

RNAi抑制人大肠癌LOVO细胞Bmi-1基因的表达

目的探讨RNA干扰（RNAi）技术沉默Bmi-1基因表达对人大肠癌细胞株LOVO增殖和侵袭力的影响及机制。方法将化学法合成的针对Bmi-1mRNA不同位点设计的3对siRNA序列（siR-NA1～3）和1对带有荧光标记的FAM-siRNA（siRNA4）转染至人大肠癌LOVO细胞,荧光显微镜下观察siRNA的转染效率,QRT-PCR检测Bmi-1mRNA表达抑制作用,Western Blot检测Bmi-1蛋白表达变化,MTT法检测LOVO细胞体外增殖变化,小室侵袭实验检测LOVO细胞侵袭能力。结果利用荧光标记的Oligo观察到siRNA转染效率达70%。siRNA1对mRNA表达抑制率最高,从而筛选出沉默效应最强的siRNA序列为siRNA1。siRNA1转染组LOVO细胞Bmi-1蛋白表达,增殖及侵袭力明显低于阴性对照组和空白对照组（P〈0.05）。结论化学合成的靶向Bmi-1siRNA转染人大肠癌LOVO细胞能有效抑制Bmi-1的mRNA和蛋白质表达水平,Bmi-1基因的RNA干扰可有效抑制人大肠癌LOVO细胞的增殖和侵袭能力。     

Six1对甲状腺癌细胞侵袭迁移的影响

目的探讨Six1对甲状腺癌细胞侵袭迁移的影响。方法甲状腺癌BCPAP细胞转染Six1小干扰RNA(Six1 siRNA)和小干扰RNA阴性对照(siRNA control),采用细胞划痕实验检测细胞迁移,Transwell小室检测细胞侵袭,Western印迹检测Six1、神经钙黏素(N-cadherin)、上皮钙黏附素(E-cadherin)蛋白表达。结果转染siRNA control后的BCPAP细胞迁移率、侵袭细胞数目及细胞中Six1、N-cadherin、E-cadherin蛋白表达水平与没有转染的BCPAP细胞相比无变化。转染Six1 siRNA后的BCPAP细胞迁移率、侵袭细胞数目及细胞中Six1、N-cadherin蛋白表达水平与没有转染的BCPAP细胞相比明显降低,而E-cadherin蛋白水平明显升高。结论敲低Six1可能通过影响E-cadherin、N-cadherin表达抑制甲状腺癌细胞侵袭迁移。     

RNA干扰沉默NF-κB p65基因表达抑制胰腺癌PANC1细胞增殖与侵袭的研究

目的 运用RNA干扰技术阻断人胰腺癌细胞株PANC1的NF-κB p65表达,观察该基因沉默后对细胞增殖能力及体外侵袭能力的影响.方法 采用阳离子脂质体LipofectamineTM 2000将化学合成的人NF-κB p65的小干扰RNA(siRNA)转染人胰腺癌细胞PANC1作为siRNA组,另设无同源性siRNA转染细胞的阴性对照组和蒸馏水空白对照组.实验重复6次.应用RT-PCR检测转染细胞NF-κB p65 mRNA与细胞间黏附分子-1(ICAM-1)mRNA的表达.MTT结合克隆形成实验测定细胞生长抑制率.Matrigel细胞侵袭实验测定细胞体外侵袭能力.结果 siRNA组、阴性对照组和空白对照组NF-κB p65 mRNA相对表达量分别为0.227±0.045、0.381±0.038和0.404±0.031;ICAM-1 mRNA相对表达量分别为0.597±0.083、0.983±0.068和1.027±0.098;细胞生长抑制率(72 h)分别为18.3%、2.3%和0;克隆形成率分别为(14.1±3.1)%、(24.5±2.1)%和(27.2±2.6)%;侵袭细胞数分别为80.25±6.35、123.83±8.80和127.68±9.23.siRNA组均明显低于2个对照组(P＜0.01).结论 NF-κB p65的RNA干扰能抑制胰腺癌PANC1细胞NF-κB p65 mRNA和ICAM-1 mRNA的表达,抑制细胞的生长和侵袭.     

siRNA抑制PTTG表达对人结肠癌LoVo细胞生物学活性的影响

目的 探讨PTTG干扰质粒对人结肠癌LoVo细胞黏附、侵袭及迁移能力的影响.方法 分别采用MTT和Transwell小室研究转染PTTG-siRNA对结肠癌细胞LoVo黏附、侵袭及迁移的作用.结果 特异性siRNA干扰PTTG表达后,LoVo细胞黏附百分率显著低于正常对照组(P＜0.01),穿透Transwell小室的细胞百分率显著低于正常对照组,细胞迁移百分率低于正常对照组.结论 特异性siRNA干扰PPTTG表达后,LoVo细胞黏附、侵袭及迁移能力受到抑制.     

高表达重组人组织激肽释放酶7基因的前列腺癌单克隆细胞株的构建

目的：建立稳定高表达重组人组织激肽释放酶7基因（ KLK7）的前列腺癌细胞株DU145,为前列腺癌发生机制的研究奠定基础。方法 PCR法扩增KLK7 cDNA,并克隆到真核表达载体pcDNA3．1上;经过限制性内切酶酶切、DNA测序验证正确后,以脂质体法转染人前列腺癌DU145细胞;通过G418筛选,每个单克隆细胞扩大培养,建立稳定转染KLK7的DU145单克隆细胞株。采用Western blot 法检测DU145细胞株KLK7表达。结果酶切鉴定及DNA 测序分析显示 pcDNA3．1-KLK7真核表达载体成功构建;转染后,成功获得稳定高表达KLK7的DU145单克隆细胞株。 Western blot 结果显示,pcDNA3．1-KLK7转染的DU145细胞KLK7表达量明显高于转染空载体组细胞（P＜0．01）。结论 pcDNA3．1-KLK7真核表达载体的建立及稳定高表达KLK7的前列腺癌单克隆细胞株的建立,为研究KLK7在前列腺癌发生发展中的作用提供了条件。     

沉默畸胎瘤衍生生长因子-1基因对胰腺癌细胞株PANC1侵袭力的影响

目的 探讨TDGF-1基因沉默对胰腺癌细胞株PANC1侵袭力的影响.方法 设计并合成3个(S1、S2、S3)靶向TDGF-1基因的小干扰RNA(small interfering RNA,siRNA),筛选出沉默效果最好的siRNA.以该siRNA的不同浓度(3.125、6.25、12.5 nmol/L)转染PANC1细胞,并设对照组和脂质体组.采用实时定量PCR和Western blotting检测TDGF-1 mRNA和蛋白表达,以软琼脂集落培养试验和Boyden小室检测癌细胞的锚着不依赖性增殖和侵袭能力,并将转染48 h的细胞接种裸鼠,观察癌细胞的体内侵袭.结果 siRNA转染组细胞的TDGF-1 mRNA和蛋白表达水平呈浓度和时间依赖性下降,且较脂质体组明显降低(P值均＜0.01).对照组细胞集落形成数和穿膜细胞数分别为19.8±2.2和49.8±2.6;siRNA组呈浓度依赖性明显减少,12.5 nmol/L转染组分别为5.6±1.2和8.1±1.1.对照组、脂质体组和12.5 nmol/L转染组接种4周后裸鼠种植瘤体积分别为(2.228±0.026)cm3、(2.186±0.028)cm3和(0.728±0.023)cm3.对照组和脂质体组种植瘤侵犯周围肌层组织,转染细胞组未见侵犯.结论 采用RNA干扰技术沉默PANC 1细胞的TDGF-1基因表达可抑制癌细胞的侵袭力.     

胰腺癌细胞TM4SF1的表达及其对细胞增殖、迁移及侵袭能力的影响

目的 检测5株人胰腺癌细胞株中TM4SF1 mRNA的表达,探讨TM4SF1基因对癌细胞增殖、迁移及侵袭能力的影响.方法 采用实时PCR方法检测人胰腺癌细胞株MPanc96、MiaPaCa-2、HPAC、PANC1、AsPC-1的TM4SF1 mRNA表达,并与人正常胰腺导管上皮细胞（HPDE）的TM4SF1mRNA表达进行比较.应用RNA干扰方法将靶向TM4SF1的siRNA及阴性对照siRNA瞬时转染MPanc96、MiaPaCa-2细胞.采用MTS法检测转染细胞的增殖能力,Transwell小室法检测细胞的迁移及侵袭能力.结果 胰腺癌细胞株MPanc96、MiaPaCa-2、PANC1、AsPC-1、HPAC的TM4SF1 mRNA相对表达量分别为1.205±0.073、1.096±0.260、1.382±0.075、1.374±0.363、0.744±0.096,均显著高于HPDE的0.020±0.003（F =22.26,P＜0.01）.与转染阴性对照siRNA的细胞比较,TM4SF1基因表达沉默的MPanc96、MiaPaCa-2细胞的增殖无显著变化,但细胞的迁移力分别降低（62.5±7.6）％、（72.8±4.0）％,侵袭能力分别下降（69.5±5.7）％、（78.6±6.3）％.结论 TM4SF1在人胰腺癌细胞中高表达,并增强胰腺癌细胞的迁移和侵袭能力.     

1,25-Dihydroxyvitamin D3 decreases human prostate cancer cell adhesion and migration

1,25-Dihydroxyvitamin-D3 [1,25(OH)2D3], the active hormonal metabolite of vitamin D, acts through a specific nuclear receptor to inhibit proliferation and promote differentiation of several tumor cell types including the LNCaP, DU145 and PC-3 prostate cancer cell lines as well as primary prostate tumor lines. 1,25(OH)2D3 can also decrease invasion of breast and prostate cancer cell lines in vitro. We confirm this latter finding in the DU145 and PC-3 prostate cancer cell lines, and further show that 1,25(OH)2D3 inhibits overall invasion, cell adhesion and migration to the basement membrane matrix protein laminin. These changes appear to be due in part to a 1,25(OH)2D3-induced decrease in expression of alpha6 and beta4 integrins, both of which are receptors for laminin and associated with increased migration and invasion of prostate cancer cells in vitro. Blocking function of these particular integrins with antibodies inhibits both adhesion and migration of the cells. Collectively, these data demonstrate that 1,25(OH)2D3, in addition to decreasing proliferation of tumor cells, can also inhibit prostate cancer cell invasion through modulation of select cell surface adhesion molecules.     

RNAi抑制存活素基因表达对前列腺癌细胞侵袭的影响

目的 探讨存活素(survivin)基因对前列腺癌细胞侵袭的影响和可能机制. 方法 采用survivin基因小干扰RNA(small interfering RNA,siRNA)转染处理人前列腺癌细胞系PC-3后,分别采用实时-定量RF PCR和Western blot检测survivin基因和基质金属蛋白酶家族-2、-9(matrixmetalloproteinases-2、-9)mRNA和蛋白水平,分别采用软琼脂集落培养试验和Boyden小室模型试验检测癌细胞的锚着不依赖性增殖和侵袭能力;其次,将转染48 h的细胞接种裸鼠,观察对癌细胞体内侵袭的影响. 结果 软琼脂集落形成试验显示,3.125、6.250 nmol/L和12.500 nmol/L siRNA组集落形成数分别为17.8±1.6、13.6±1.5、8.8±1.4,而对照组为22.65±1.8(P<0.05);Boyden小室模型试验显示,3.125、6.250 nmol/L和12.500/ nmol/L siRNA组穿过滤膜的细胞数分别为33.6±2.1、19.5±1.9、8.1±1.8,而对照组为49.4±2.3(P<0.05).体内试验显示,对照组裸鼠组织癌细胞侵袭横纹肌和血管,而转染组未见这些现象.同时发现,转染组细胞MMP-2、-9基因mRNA和蛋白水平明显下调,呈浓度和时间依赖性(P<0.01). 结论 采用survivin siRNA转染可抑制前列腺癌细胞侵袭转移,其机制可能与下调MMP-2和MMP-9表达有关.     

Membrane androgen receptor activation induces apoptotic regression of human prostate cancer cells in vitro and in vivo

Nongenomic androgen actions imply mechanisms different from the classical intracellular androgen receptor (iAR) activation. We have recently reported the identification of a membrane androgen receptor (mAR) on LNCaP human prostate cancer cells, mediating testosterone signal transduction within minutes. In the present study we provide evidence that activation of mAR by nonpermeable, BSA-coupled testosterone results in 1) inhibition of LNCaP cell growth (with a 50% inhibitory concentration of 5.08 nM, similar to the affinity of testosterone for membrane sites); 2) induction in LNCaP cells of both apoptosis and the proapoptotic Fas protein; and 3) a significant decrease in migration, adhesion, and invasion of iAR-negative DU145 human prostate cancer cells. These actions persisted in the presence of antiandrogen flutamide or after decreasing the content of iAR in LNCaP cells by iAR antisense oligonucleotides. Testosterone-BSA was also effective in inducing apoptosis of DU145 human prostate cancer cells, negative for iAR, but expressing mAR sites. In LNCaP cell-inoculated nude mice, treatment with testosterone-BSA (4.8 mg/kg body weight) for 1 month resulted in a 60% reduction of tumor size compared with that in control animals receiving only BSA, an effect that was not affected by the antiandrogen flutamide. Our findings suggest that activators of mAR may represent a new class of antitumoral agents of prostate cancer.     

下调miR-10a表达对人胰腺癌细胞AsPC-1迁移和侵袭的影响

目的 探讨miR-10a表达对人胰腺癌AsPC-1细胞迁移和侵袭力的影响及其作用机制.方法 构建针对miR-10a的小干扰RNA（miR-10a-siRNA）,转染处理人胰腺癌AsPC-1细胞,同时设阴性对照siRNA（NC-siRNA）组和空白对照组.采用荧光实时定量PCR法检测3组细胞中miR-10a的表达水平,划痕实验检测细胞迁移,Transwell小室检测细胞侵袭能力,ELISA法检测各组癌细胞培养上清液中基质金属蛋白质酶13（MMP-13）含量.结果 对照组、NC-siRNA组和miR-10a-siRNA组AsPC-1细胞miR-10a表达水平分别为1.05±0.08、1.03 ±0.06、0.02±0.01,穿膜细胞数分别为（150±2.6）、（145±2.2）、（62±1.8）个,培养上清中MMP-13表达量分别为（108.5±2.8）、（107.8±2.5）、（35.8±1.5） pg/ml,miR-10a-siRNA组均显著低于对照组和NC-siRNA组,差异均有统计学意义（P值均＜0.01）.对照组、NC-siRNA组和miR-10a-siRNA组AsPC-1细胞的迁移后间距分别为（385 ±15）、（395±13）、（736±18）μm,miR-10a-siRNA组显著大于对照组和NC-siRNA组,差异有统计学意义（P值均＜0.01）.结论 下调miR-10a表达可抑制胰腺癌AsPC-1细胞迁移和侵袭能力,其机制可能与MMP-13表达下调有关.     

Androgen sensitivity related proteins in hormone-sensitive and hormone-insensitive prostate cancer cell lines treated by androgen antagonist bicalutamide

Members of the bcl-2 gene family and endogenous inhibitors of cyclin-dependent kinases participate in the regulation of apoptosis and cell cycle in a diverse range of cell types and are implicated in the development of hormone refractory prostate cancer and resistance to anti-cancer therapy. The expression of several of these genes can be regulated by steroid hormones and related agents via their nuclear receptors. However, insufficient information considering the protein expression after the treatment by hormone antagonists is available. The aim of this study was to evaluate the expression of anti- and pro-apoptotic proteins, (Bcl-2, Bax), and to correlate this with the appearance of some nuclear receptors and cell cycle related proteins in androgen sensitive and androgen insensitive prostate cancer cell lines, LNCaP and DU-145, after the treatment by androgen antagonist bicalutamide. Our results revealed that androgen receptor (AR) expression in LNCaP cells decreased, however in DU-145 cells AR slightly increased following anti-androgen treatment. The same agent stimulated expression of p21Waf1/Cip5 and p27Kip1 in LNCaP, as well as in DU-145 cell lines. Bcl-2 level increased slightly in LNCaP cells and, in DU-145 cells was almost undetectable. Bax expression was not changed in LNCaP but significantly decreased in DU-145 cells. Similarly, retinoid X receptor beta (RXRbeta) level was significantly down regulated after 24 hours in DU-145 and also in LNCaP cells after 72 hours. These results confirm that androgen withdrawal therapy employing anti-androgens may elicit different signalling pathways in various types of prostate cancer that may be dependent on AR status and AR sensitivity.     

Insulin-like growth factor-I receptor signalling and acquired resistance to gefitinib (ZD1839; Iressa) in human breast and prostate cancer cells

De novo and acquired resistance to the anti-tumour drug gefitinib (ZD1839; Iressa), a specific epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) has been reported. We have determined whether signalling through the IGF-I receptor (IGF-1R) pathway plays a role in the gefitinib-acquired resistance phenotype. Continuous exposure of EGFR-positive MCF-7-derived tamoxifen resistant breast cancer cells (TAM-R) to 1 microM gefitinib resulted in a sustained growth inhibition (90%) for 4 months before the surviving cells resumed proliferation. A stable gefitinib-resistant subline (TAM/TKI-R) was established after a further 2 months and this showed no detectable basal phosphorylated EGFR activity. Compared with the parental TAM-R cells, the TAM/ TKI-R cells demonstrated (a) elevated levels of activated IGF-1R, AKT and protein kinase C (PKC)delta, (b) an increased sensitivity to growth inhibition by the IGF-1R TKI AG1024 and (c) an increased migratory capacity that was reduced by AG1024 treatment. Similarly, the EGFR-positive androgen-independent human prostate cancer cell line DU145 was also continuously challenged with 1 microM gefitinib and, although substantial growth inhibition (60%) was seen initially, a gefitinib-resistant variant (DU145/TKI-R) developed after 3 months. Like their breast cancer counterparts, the DU145/TKI-R cells showed increases in the levels of components of the IGF-1R signalling pathway and an elevated sensitivity to growth inhibition by AG1024 compared with the parent DU145 cell line. Additionally, DU145/TKI-R cell migration was also decreased by this inhibitor. We have therefore concluded that in breast and prostate cancer cells acquired resistance to gefitinib is associated with increased signalling via the IGF-1R pathway, which also plays a role in the invasive capacity of the gefitinib-resistant phenotype.