Ki67基因RNA干扰增殖型腺病毒对肺癌细胞增殖的抑制作用

 目的 探讨Ki67基因小干扰RNA（Ki67．siRNA）增殖型腺病毒对肺癌细胞的示伤作用及IXlD／的表达情况。方法 提取重组腺病毒的DNA，PCR鉴定正确后，大量扩增，氯化铯梯度离心纯化，测病毒滴度。ZD-Ki67感染人肺癌细胞系（A549），通过荧光显微镜下观察和结晶紫染色法检测细胞病作用、IVITT法检测细胞存活、Western印迹法检测E1A、逆转录-聚合酶链反应（RT-PCR）检测Ki67表达。结果 PCR鉴定表明ZD55-Ki67包含目的基因且无野生型腺病毒的污染；ZD55-Ki67滴度为4．5×1010PFU／ml免疫印迹法证实ZD55-Ki67在肿瘤细胞中表达E1A；ZD55-Ki67抑制Ki67表达及肺癌细胞生长的作用显著优于Ad-Ki67。结论 ZD55-Ki67能够有效抑制Ki67基因的表达，降低肺癌细胞的增殖能力，为肺癌研究和抗肿瘤基因治疗提供新的策略。     

Ki67基因干扰对裸鼠人肾癌细胞移植瘤的抑制作用

目的:探讨靶向Ki67基因干扰腺病毒(Ad-Ki67)对裸鼠人肾癌移植瘤Ki-67基因表达和肿瘤生长的影响.方法:建立人肾癌移植瘤模型,瘤体内注射Ad-Ki67,定期测量肿瘤体积,激光共聚焦显微镜观察移植瘤组织Ki-67抗原表达,原位末端标记法(TUNEL)检测肿瘤细胞凋亡.结果:Ad-Ki67能将Ki67基因有效沉默.Ad-Ki67组和Ad-EGFP组Ketr-3细胞Ki-67抗原表达水平分别为对照组的(78.7±6.5)%、(95.4±8.6)%:与对照组细胞凋亡阳性率(10.7±2.4)%比较,Ad-Ki67、Ad-EGFP组分别为(43.7±3.6)%和(21.8±2.5)%,表明Ad-Ki67能有效诱导肿瘤细胞凋亡;Ad-Ki67能显著抑制肿瘤的生长,接种5周后Ad-Ki67组肿瘤体积为(469.5±41.6)mm,.Ad-EGFP组为(664.3.5±47.8)mm3,PBS组为(884.9±52.5)mm3.结论:靶向Ki67基因的干扰腺病毒Ad-Ki67对裸鼠肾癌移植瘤有显著的治疗效果,为治疗肾癌提供新的平台.     

转录hTERT基因shRNA的溶瘤腺病毒的构建及抗肿瘤效应

目的构建转录端粒酶逆转录酶(hTERT)基因小发夹RNA(hTERT-shRNA)的条件增殖腺病毒。方法设计能转录hTERT-shRNA的模板DNA序列,煺火后克隆至pCA13质粒,构建重组质粒pCA13-hTERT。用Bg1Ⅱ从pCA13-hTERT酶切出包含CMV启动子及hTERT-shRNA模板的表达框,将表达框克隆入条件增殖腺病毒质粒pZD55,构建重组质粒pZD55-hTERT。将pZD55-hTERT与腺病毒右臂质粒pBHGE3共转染293细胞,9~12天后出现病毒空斑。提取重组腺病毒的DNA,PCR鉴定正确者即为条件增殖腺病毒ZD55-hTERT。大量扩增,氯化铯梯度离心纯化,测滴度。感染人肝癌细胞株(BEL-7404),通过荧光显微镜、结晶紫染色法观察细胞病作用,MTT法检测细胞存活情况。结果酶切分析、测序鉴定表明pCA13-hTERT构建成功;PCR、酶切分析、测序鉴定表明pZD55-hTERT构建成功;PCR鉴定表明ZD55-hTERT包含目的基因且无野生型腺病毒的污染;ZD55-hTERT滴度为1×1011PFU/m l;ZD55-hTERT在肝癌细胞株BEL-7404中可导致明显细胞病变效应。结论成功构建的ZD55-hTERT为利用hTERT-shRNA靶向肿瘤治疗奠定了基础。     

Vasostatin基因重组腺病毒载体的构建及其对胰腺癌生长的抑制作用

目的以复制缺陷型腺病毒为载体,构建vasostatin基因重组腺病毒,并观察其对胰腺癌裸鼠移植瘤生长的抑制作用.方法以人肌肉cDNA文库为模板应用PCR的方法扩增出vasostatin的DNA片断,定向插入腺病毒穿梭质粒pshuttle-CMV经酶切、测序鉴定正确后,电穿孔法将重组穿梭质粒转化E. coli BJ5183-AdEasy-1感受态细菌,行细菌内同源重组.将抗性筛选和酶切鉴定正确的重组质粒pAd-CMV-vasostatin转染293细胞进行包装.病毒扩增纯化后,病毒感染人胰腺癌细胞,RT-PCR和Western印迹法检测vasostatin的表达状况.复制人胰腺癌裸鼠移植瘤模型,瘤内注射107pfu pAd-CMV-vasostatin、108pfu pAd-CMV-LacZ及PBS,观察移植瘤的生长曲线及瘤重.结果PCR产物电泳后可见长度为560bp左右的目的条带;酶切及测序鉴定表明穿梭质粒pshuttle-CMV中插入了vasostatin的DNA片断;卡那霉素抗性筛选及Pac Ⅰ酶切鉴定证实腺病毒重组质粒pAd-CMV-vasostatin构建成功;转染293细胞7天后观察到细胞病理学效应出现.PCR鉴定表明重组腺病毒中含有vasostatin片断.RT-PCR和Western印迹法证实vasostatin mRNA及蛋白的表达.治疗后3周pAd-CMV-vasostatin组移植瘤的体积及瘤重均显著小于pAd-CMV-LacZ组及PBS组.结论含有vasostatin基因的重组腺病毒构建成功,并可显著抑制人胰腺癌裸鼠移植瘤的生长.     

全反式维甲酸对结肠癌细胞XIAP相关因子1表达的影响

目的了解全反式维甲酸对结肠癌lovo细胞XIAP相关因子1(XAF1)表达及细胞增殖的影响。方法以不同浓度的ATRA刺激lovo细胞,RT-PCR检测XAF1的mR-NA水平变化,Westernblot分析XAF1蛋白水平的表达;MTT法检测ATRA对lovo细胞生长抑制率。构建含有XAF1启动子序列荧火虫荧光素酶报告质粒,分析ATRA作用对XAF1启动子活性的影响。结果经ATRA作用,lovo细胞mRNA和蛋白的表达水平上调,细胞生长受到抑制。上述效应均具有药物浓度依赖性。报告基因分析结果显示,ATRA使含有XAF1启动子序列荧火虫荧光素酶报告质粒的虫荧光素酶的活性增加。结论ATRA通过促进启动子转录活性上调XAF1的mRNA和蛋白表达水平,并抑制结肠癌细胞的生长。     

罗勒多糖对肿瘤转移行为的影响

目的:研究腺病毒介导的鼠内皮抑素基因对胃癌的治疗作用.方法:利用病毒重组技术将内皮抑素克隆入增殖缺陷型腺病毒基因组中,观察体外转染表达后的生物学活性.通过建立荷人胃癌的裸鼠动物模型,分析基因转导后动物肿瘤细胞中内皮抑素的表达情况及对肿瘤的抑制作用.结果:构建了表达内皮抑素的重组腺病毒载体pCA13-mEndo;检测到内皮抑素在体外的mRNA水平和蛋白质水平均有表达;鸡胚绒毛尿囊膜实验表明其对血管生长起抑制作用;荷瘤裸鼠体内肿瘤生长抑制明显.结论:所构建的pCA13-mEndo重组腺病毒载体可有效表达具有生物学活性的内皮抑素,使得肿瘤内微血管生成减少,肿瘤细胞增殖减慢,为抗血管生成方法治疗实体瘤的临床应用奠定基础.     

同时针对VEGF和p53腺病毒干扰载体的构建及干扰作用

目的:构建能同时干扰VEGF和p53基因表达的RNAi腺病毒干扰载体,观察其对肿瘤细胞VEGF和p53的干扰作用.方法:先分别构建能干扰p53和VEGF的质粒载体,依次将构建干扰载体的干扰序列和H1启动子序列切下并连接到pAdTrack上,构建成pAdTrack/VEGF/p53,将构建的质粒转染含有pAdEasy-1的BJ5183工程菌中,回收并酶切鉴定重组腺病毒载体,将阳性腺病毒载体感染293细胞并收集病毒,采用荧光定量PCR检测腺病毒干扰载体同时降低VEGF和p53表达的作用.结果:经过酶切鉴定,pAd/VEGF/p53载体中含有插入的2个启动子和干扰序列.转染腺病毒干扰载体后,肿瘤细胞中的VEGF和p53 mRNA表达量显著降低.结论:构建能同时干扰VEGF和p53基因的腺病毒干扰载体可以显著降低MCF-7细胞中VEGF和p53 mRNA的表达.     

量子点分子探针双标记技术研究癌细胞克隆生长行为

目的 研究癌细胞的克隆生长行为,分析癌细胞的增殖特点。方法 以乳腺癌MCF-7细胞、结肠癌SW480细胞和胃癌SGC7901细胞为研究对象,进行细胞克隆的形态学特点研究。用量子点分子探针双色标记技术,以绿色量子点标记癌细胞胞质,黄、红色量子点标记癌细胞胞核Ki67,观察癌细胞克隆的形成速度,克隆内细胞形态、离散趋势、Ki67表达分布情况。结果 细胞克隆形成实验可见,乳腺癌MCF-7细胞生长6天形成克隆,结肠癌SW480细胞生长8天形成克隆,胃癌SGC7901细胞生长12天形成克隆。三种细胞均具有明显异型性特点;核质比大,易见病理性核分裂相;克隆周边细胞形成较多突触。部分克隆中,边缘细胞与克隆分离或呈分离趋势。量子点探针技术检测可见,大部分Ki67强阳性细胞分布于克隆周边或集中于一侧。结论 Ki67广泛表达于MCF-7、SW480和SGC7901三种癌细胞,且在癌细胞克隆周边表达更强或集中于一侧,癌细胞克隆呈现明显的不对称生长行为。     

Med-19对结肠癌细胞增殖及凋亡的影响

背景与目的:Med-19目前被定义为肿瘤转移相关基因,但对其在结肠癌中的功能还知之甚少。本文旨在检测Med-19基因在结肠癌中的表达及其与临床病理参数间的相关性,观察Med-19对结肠癌细胞增殖和凋亡的影响。方法:利用免疫组化检测Med-19基因在115例结肠癌中的表达情况;构建Med-19-siRNA载体转染结肠癌caco-2细胞,MTT法检测癌细胞的增殖活性,流式细胞术分析细胞凋亡的变化。结果:Med-19基因在结肠癌中的表达阳性率为64.3%,远远高于相应癌旁组织的27.8%,差异有统计学意义(P<0.05)。深入分析发现Med-19基因的表达水平与Dukes分期、淋巴结转移密切相关,而与年龄、性别、分化程度无关。与空载体转染组相比,MTT结果表明,Med-19-siRNA载体转染的caco-2细胞生长明显受到抑制,差异有统计学意义(P<0.05),流式细胞术结果提示,Med-19-siRNA载体转染的caco-2细胞凋亡比例升高,差异有统计学意义(P<0.05)。结论:Med-19基因在结肠癌中高表达,下调Med-19基因的表达可抑制结肠癌细胞增殖,促进结肠癌细胞凋亡,提示Med-19基因可以作为结肠癌治疗的潜在基因靶点。     

miR-320a抑制结肠癌细胞增殖及肺转移作用的研究

摘 要：［目的］ 探讨调节结肠癌细胞中miR-320a的表达水平后,其对结肠癌细胞生物学行为的影响及可能作用机制。［方法］ 检测调节miR-320a结肠癌细胞的表达水平后,用MTT法检测细胞增殖能力的变化,Transwell侵袭实验检测细胞侵袭力变化,通过给裸鼠尾静脉注射miR-320a不同表达水平的结肠癌细胞后,观察裸鼠肺转移的情况;通过生物信息学软件预测miR-320a的潜在靶基因并通过双荧光素酶报告基因系统进行鉴定,Western Blot法检测β-catenin、MMP-2、MMP-9、E-cadherin、N-cadherin和Vimentin的蛋白表达情况。［结果］ 通过慢病毒感染miR-320a质粒上调结肠癌细胞中miR-320a水平后,可以抑制结肠癌细胞增殖、抑制结肠癌细胞侵袭及肺转移,β-catenin是miR-320a的靶基因,miR-320a下调β-catenin、MMP-2、MMP-9、N-cadherin和Vimentin表达,上调E-cadherin表达。［结论］ miR-320a可以抑制结肠癌细胞的增殖及侵袭转移。     

Effects of G250 promoter controlled conditionally replicative adenovirus expressing Ki67-siRNA on renal cancer cell

Replication-competent adenovirus (RCAd) has been used extensively in cancer gene therapy, and tumor-selection is critical for the use of replication-competent adenovirus. Here we investigated the anti-tumor characterization of oncolytic virus, whose E1A gene is under the control of a renal cell carcinoma specific promoter - the G250 promoter. The constructed oncolytic virus G250-Ki67 is armed with transgene of Ki67-siRNA, and G250-ZD55-Ki67 also with E1B-55 KD deleted. The tumor-specific expression of E1A and Ki67 was demonstrated by Western blot and immunohistochemistry staining, and the tumor-specific cytotoxicity was assessed by crystal violet staining and cell viability assays. The G250-Ki67 and G250-ZD55-Ki67 adenoviruses could express E1A protein in 786-O and OSRC cell lines but not in ACHN and HK-2 cell lines. The expression of Ki67 gene in 786-O and OSRC cell lines were suppressed by these adenoviruses. The cytotoxic effects induced by G250-ZD55-Ki67 and G250-Ki67 were more obvious on the 786-O cell lines than on the OSRC cell lines. Each group of adenoviruses could inhibit the proliferation of the 786-O cells and OSRC cells. However, the effects induced by G250-ZD55-Ki67 and G250-Ki67 on 786-O cells were stronger than on OSRC cells. Moreover, G250-ZD55-Ki67 had enhanced antitumor activities in these renal cancer cells compared with G250-Ki67. G250 promoter-derived CRAds carrying Ki67-siRNA could highly amplify and express Ki67-siRNA in renal cancer cells with expression of G250 antigen, inhibit renal cancer cells proliferation and induce apoptosis. These results demonstrated that the G250-specific oncolytic adenovirus expressing Ki67-siRNA is applicable for human renal clear cell cancer therapy.     

抑制TPD52基因表达对结直肠癌细胞凋亡及ROS含量的影响

目的:探讨抑制肿瘤蛋白D52（TPD52）基因表达对结直肠癌细胞活力、凋亡率及活性氧(reactive oxygen species,ROS)含量的影响及机制。方法:正常结肠NCM460细胞作为对照细胞,分别用RT-PCR及Western blotting检测人结直肠癌Caco2、SW480、HCT116、HT29细胞TPD52的mRNA及蛋白表达。以LipofectamineTM 2000为载体,将抑制TPD52表达的siRNA（TPD52-siRNA）及阴性对照siRNA（NC）转染HCT116细胞,转染48 h,MTT检测细胞活力,流式细胞术检测细胞凋亡率及ROS含量;Western blotting检测各组细胞增殖相关蛋白Ki67和PCNA及凋亡相关蛋白Bax和Survivin的蛋白表达。结果:与正常结肠NCM460细胞比较,Caco2、SW480、HCT116、HT29细胞中TPD52的mRNA及蛋白表达均明显升高,差异均具有统计学意义（P＜0.05）。转染TPD52-siRNA的HCT116细胞TPD52的mRNA及蛋白表达均明显降低,与空白对照组和NC组比较差异具有统计学意义（P＜0.05）。与NC组比较,TPD52-siRNA组细胞活力明显降低,凋亡率升高,ROS含量升高,Ki67、PCNA和Survivin的蛋白表达明显降低,Bax的蛋白表达明显升高,差异均具有统计学意义（P＜0.05）。结论:TPD52基因表达抑制可降低结直肠癌细胞活力和诱导凋亡,机制可能与细胞内ROS水平提高及Ki67、PCNA、Survivin表达下调和Bax表达上调有关。     

Notch3-siRNA增强结肠癌细胞对托泊替康的化疗敏感性

目的：探讨下调Notch3表达是否可增强结肠癌SW620细胞对化疗药托泊替康（topotecan）的敏感性。方法：将Notch3siRNA转染到SW620细胞中,Westernblotting检测转染后SW620细胞中Notch3的表达水平。转染后不同时间加入托泊替康,MTr法检测SW620细胞的增殖;Hoechst33342染色和流式细胞仪检测SW620细胞的凋亡;Caspase-3活化试剂盒检测SW620细胞中caspase-3的活化。结果：Notch3siRNA转染可明显抑制SW620细胞中Notch3蛋白的表达;托泊替康作用于Notch3siRNA转染组细胞的IC50较对照CtrlsiRNA转染组显著降低（P〈0．05）;流式细胞仪检测显示沉默Notch3的表达可显著增强托泊替康诱导的结肠癌细胞凋亡（P〈0．05）和caspase-3活化（P〈0．05）。结论：siRNA沉默Notch3的表达可增强SW620细胞对托泊替康的化疗敏感性。     

长链非编码RNA CCAT2对结肠癌细胞增殖和凋亡的影响及机制探讨

目的:观察长链非编码RNA（lncRNA）结肠癌相关转录本2（CCAT2）在结肠癌细胞系中的表达及对细胞增殖和凋亡的影响,并探讨其机制。方法:采用荧光定量PCR技术（qRT-PCR）检测结肠癌细胞系HCT116、SW620、LOVO、HT29与正常结肠上皮细胞系NCM460中lncRNA CCAT2的表达。将结肠癌细胞系SW620分成CCAT2-siRNA组、Control-siRNA组及Mock组,CCAT2-siRNA组和Control-siRNA组经LipofectamineTM 2000分别转染CCAT2-siRNA及Control-siRNA,Mock组以PBST作对照。MTT实验和流式细胞术分别测定增殖和凋亡能力,Western blot测定p53、裂解型聚腺苷二磷酸-核糖聚合酶（PARP）及B细胞淋巴瘤/白血病-2（Bcl-2）蛋白的表达。结果:lncRNA CCAT2在结肠癌细胞系LOVO、HT29、HCT116、SW620中均比正常结肠上皮细胞系NCM460表达水平升高（P＜0.05)。MTT示:转染后0 h、24 h、48 h,CCAT2-siRNA组与Control-siRNA组OD490 nm值差异无统计学意义（P＞0.05)。转染后72 h、96 h,CCAT2-siRNA组OD490 nm值低于Control-siRNA组（P＜0.05)。CCAT2-siRNA组细胞凋亡率高于Control-siRNA组（P＜0.01）。与Control-siRNA组相比,CCAT2-siRNA组p53、裂解型PARP表达上调,Bcl-2蛋白表达下调。结论:lncRNA CCAT2在结肠癌细胞系中高表达,敲低lncRNA CCAT2表达可抑制结肠癌细胞增殖,并诱导凋亡,其机制可能与p53、裂解型PARP表达上调,Bcl-2蛋白表达下调有关。     

Inhibiting Colorectal Carcinoma Growth and Metastasis By Blocking the Expression of VEGF Using RNA Interference

Angiogenesis plays an essential role in tumor growth and metastasis and is a promising target for cancer therapy. Vascular endothelial growth factor (VEGF) is a key regulator of angiogenesis. The present study was designed to determine the role of VEGF in tumor growth and metastasis using RNA interference (RNAi) technology. Four small interfering RNA (siRNA) sequences for the VEGF gene were cloned into expression plasmids and transfected into human colorectal carcinoma (CRC) SW620 cells. Stable transfection of these plasmids decreased VEGF protein expression, leading to the potent suppression of tumor cell proliferation, migration, invasion, and angiogenesis in vitro. Furthermore, in subcutaneous and intrasplenic/portal injection models involving athymic nude mice, the tumor growth and metastasis of SW620 cells expressing VEGF siRNA were significantly inhibited compared with untransfected cells or cells transfected with control vector alone. Immunohistochemical analyses of tumor sections revealed a decreased vessel density and decreased VEGF expression in the animals where siRNA against VEGF were expressed. These results indicate that RNAi of VEGF can be an effective antiangiogenic strategy for CRC.     

NDRG2基因对结肠癌细胞SW620增殖和侵袭力的影响

目的 观察N-myc下游调节基因2(NDRG2)对结肠癌细胞SW620生长和侵袭能力的影响,并探讨其机制.方法 采用阳离子脂质体转染方法,分别将pcDNA3.1-NDRG2和siRNA-NDRG2转染入SW620细胞内,以空白组作为对照.Western blotting检测各组细胞NDRG2以及基质金属蛋白酶-2(MMP-2)的表达情况;细胞侵袭试验对各组细胞侵袭能力进行分析;四甲基偶氮唑蓝法对各组细胞生长曲线进行测定.结果 pcDNA3.1-NDRG2转染入SW620细胞后,NDRG2蛋白表达升高,而MMP-2蛋白表达降低;siRNA-NDRG2转染入SW620细胞后,NDRG2蛋白表达降低,而MMP-2蛋白表达升高.pcDNA3.1组的穿膜细胞数(56.20±7.40)及siRNA组穿膜细胞数(94.20 ±9.23)分别与对照组(75.80 ±4.82)相比,差异具有统计学意义(t=13.102,P=0.000;t=11.820,P=0.000).生长曲线显示,转染后第5天,pcDNA3.1组细胞吸光度值(0.46 ±0.01)及siRNA组细胞吸光度值(0.91 ±0.02)分别与对照组(0.67 ±0.01)相比,差异具有统计学意义(t=9.561,P=0.000;t=10.922,P=0.000).结论 NDRG2能降低结肠癌细胞SW620的侵袭和增殖能力,其机制可能与下调MMP-2的表达有关.     

Colon cancer cell-derived tumor necrosis factor-alpha mediates the tumor growth-promoting response in macrophages by up-regulating the colony-stimulating factor-1 pathway

The interplay between malignant and stromal cells is essential in tumorigenesis. We have previously shown that colony-stimulating factor (CSF)-1, matrix metalloprotease (MMP)-2, and vascular endothelial growth factor (VEGF)-A production by stromal cells is enhanced by CSF-1-negative SW620 colon cancer cells. In the present study, the mechanisms by which colon cancer cells up-regulate host factors to promote tumorigenesis were investigated. Profiling of tumor cell cytokine expression in SW620 tumor xenografts in nude mice showed increased human tumor necrosis factor (TNF)-alpha mRNA expression with tumor growth. Incubation of macrophages with small interfering (si) RNAs directed against TNF-alpha or TNF-alpha-depleted SW620 cell conditioned medium versus SW620 cell conditioned medium failed to support mouse macrophage proliferation, migration, and expression of CSF-1, VEGF-A, and MMP-2 mRNAs. Consistent with these results, human TNF-alpha gene silencing decreased mouse macrophage TNF-alpha, CSF-1, MMP-2, and VEGF-A mRNA expression in macrophages cocultured with human cancer cells. In addition, inhibition of human TNF-alpha or mouse CSF-1 expression by siRNA reduced tumor growth in SW620 tumor xenografts in mice. These results suggest that colon cancer cell-derived TNF-alpha stimulates TNF-alpha and CSF-1 production by macrophages, and that CSF-1, in turn, induces macrophage VEGF-A and MMP-2 in an autocrine manner. Thus, interrupting tumor cell-macrophage communication by targeting TNF-alpha may provide an alternative therapeutic approach for the treatment of colon cancer.     

Hyaluronan synthase-3 is upregulated in metastatic colon carcinoma cells and manipulation of expression alters matrix retention and cellular growth

HA is a glycosaminoglycan that is synthesized on the inner surface of the plasma membrane and secreted into the pericellular matrix. HA and its biosynthetic enzymes (HAS1, HAS2 and HAS3) are thought to participate in tumor growth and cancer progression. In our study, colon carcinoma cells isolated from a lymph node metastasis (SW620) produced more pericellular HA and expressed higher levels of HAS3 mRNA compared to cells isolated from a primary colon carcinoma (SW480). To assess functionality, HAS3 expression in SW620 cells was inhibited by transfection with an asHAS3 construct. Decreased HA secretion and cell-surface retention by asHAS3 transfectants were confirmed using competitive binding and particle exclusion assays. Anchorage-independent growth, a correlate of tumor growth in vivo, was assessed by colony formation in soft agar. SW620 cells stably transfected with asHAS3 demonstrated significant growth inhibition, as evidenced by fewer colonies and smaller colony area than either SW620 cells or cells transfected with vector alone. Addition of exogenous HA restored growth in asHAS3 transfectants. Thus, we demonstrate that pericellular HA secretion and retention and HAS3 expression are increased in metastatic colon carcinoma cells relative to cells derived from a primary tumor. Inhibition of HAS3 expression in these cells decreased the pericellular HA matrix and inhibited anchorage-independent growth. These data suggest that HA and HAS3 function in the growth and progression of colon carcinoma.     

XIAP siRNA对TRAIL诱导结肠癌细胞SW620凋亡能力的影响

 目的
研究XIAP siRNA对肿瘤坏死因子相关的凋亡诱导配体(Tumor Necrosis Factor-related Apoptosis-Inducing Ligand,TRAIL)诱导结
肠癌细胞SW620凋亡的影响。方法SW620细胞分为转染XIAP siRNA组、空转染对照组或者siRNA阴性对照组,然后给予TRAIL处理。XIAP
表达水平的变化、细胞增殖抑制、Caspase-3活性分别由Western blot、MTT法和Caspase-3荧光测定来检测。切割PARP的表达水平由
Western blot来测定。结果XIAP siRNA转染以后显著下调XIAP蛋白表达水平。和空转染对照组、siRNA阴性对照组相比,XIAP siRNA
显著增强10、100、1 000 ng/ml等浓度的TRAIL作用以后SW620细胞的增殖抑制、Caspase-3活性和激活PARP。结论 XIAP siRNA能显
著增强TRAIL诱导结肠癌细胞SW620的凋亡。