siRNA沉默Annexin-1基因对膀胱癌T24细胞生物学特性的影响

目的观察RNA干扰技术沉默Annexin-1基因表达对膀胱癌T24细胞增殖能力的影响。方法针对Annexin-1基因不同部位设计并化学合成3对不同的靶向小干扰RNA(siRNA),脂质体介导瞬时转染膀胱癌T24细胞,转染后应用半定量RT-PCR和Western印迹法检测Annexin-1mRNA和蛋白的改变,透射电镜观察细胞凋亡情况,用MTT法检测沉默Annexin-1表达对膀胱癌T24细胞增殖的影响。结果转染siRNA后膀胱癌T24细胞Annexin-1mRNA和蛋白水平显著下降(P0.05),转染siRNA沉默Annexin-1基因表达后膀胱癌T24细胞出现典型凋亡细胞,增殖能力显著下降(P0.05)。结论 RNA干扰Annexin-1基因后其mRNA和蛋白水平显著下降,诱导了膀胱癌T24细胞凋亡,并且抑制细胞的增殖。     

siRNA沉默ERCC1基因表达对结肠癌细胞奥沙利铂耐药的影响和机制

目的 采用小干扰RNA(siRNA)技术作用于人结肠癌细胞HCT116中的ERCC1,探讨其对结肠癌铂类耐药细胞株增殖、凋亡的影响。方法 体外培养结肠癌奥沙利铂耐药细胞株HCT116/L-OHP并验证其耐药性;qRT-PCR和蛋白印迹技术检测细胞和组织中ERCC1表达量的变化;采用siRNA-NC和siRNA-ERCC1转染细胞,CCK-8法检测耐药细胞的增殖能力,流式细胞术检测耐药细胞的凋亡变化。结果 结肠癌耐药组织和人结肠癌耐药细胞HCT116/L-OHP ERCC1的表达水平明显升高(P<0.05);转染siRNA ERCC1后,HCT116/L-OHP细胞中的ERCC1 mRNA和蛋白水平明显降低(P<0.05);奥沙利铂联合处理后,siRNA ERCC1转染使HCT116/L-OHP细胞的增殖活性下降、凋亡率升高。结论 siRNA能有效下调ERCC1基因表达,抑制细胞增殖,增加细胞凋亡,增强奥沙利铂对耐药细胞株HCT116/L-OHP的杀伤作用。     

表浅性膀胱癌细胞中DNA核酸内切酶ERCC1及膜连蛋白-1的表达及与顺铂耐药的关系

目的 探讨表浅性膀胱癌细胞中DNA核酸内切酶ERCC1基因的表达在介导顺铂(Cisplatin)耐药中的作用.方法 用分步诱导法在体外建立耐Cisplatin不同浓度、不同天数表浅性膀胱癌细胞KU7和253JB-V (0 nmol/L,0 d;0.4 nmol/L,30、75 d;0.8 nmol/L,30 d)和T24(0 nmol/L,0 d;0.2 nmol/L,90 d).MTT方法检测Cisplatin对建立的耐药株细胞系的半数抑制浓度(IC50);RT-PCR方法检测ERCC1、膜连蛋白-1(Annexin-1)mRNA的表达变化.结果 MTT结果显示:Cisplatin作用96 h后,耐药株细胞的耐药程度明显增强;对KU7耐药株细胞、253JB-V耐药株细胞和T24耐药株细胞而言,KU7 +0.4 nmol/L Cisplatin(75 d)和KU7+ Cisplatin 0.8 nmol/L(30 d)对Cisplatin的敏感性下降,其IC50由0.8 nmol/L(0 nmol/L,0d)逐步增高到1.45 nmol/L;同样的情况也发生在253JB-V耐药株细胞和T24耐药株细胞中.RT-PCR结果显示:KU7耐药株细胞、253JB-V耐药株细胞的ERCCl mRNA表达增多,且在高浓度和天数多时更为明显,Annexin-1基因无明显变化.T24耐药株细胞中ERCC1基因及Annexin-1基因均无明显变化.结论 成功地在体外诱导了耐Cisplatin不同浓度的KU7耐药株细胞、253JB-V耐药株细胞各两株,T24耐药株细胞一株.其中KU7耐药株细胞、253JB-V耐药株细胞ERCC1基因的表达量随着加药浓度和天数的增加而增多,Annexin-1基因无明显变化.T24耐药株细胞的ERCC1基因及Annexin-1基因表达均无明显的变化.     

卡介苗加顺铂膀胱灌注治疗膀胱癌30例

1992～ 1999年 ,我们对 3 0例膀胱肿瘤术后患者采用卡介苗 ( BCG)与顺铂联合膀胱内灌注治疗 ,疗效明显优于单用BCG或其他化疗药物灌注 ,现报告如下。临床资料 :本组男 2 1例 ,女 9例 ;年龄 2 9～ 70岁 ,平均 45岁 ;病程 2个月至 5年 ,平均 1年。病理检查均证实为膀胱移行上皮乳头状癌。临床分期为 A期 2 4例、B期 6例 ;细胞学分级为 级 5例、 级 14例、 ～ 级 11例。 3 0例均行开放性手术 ,其中单纯肿瘤切除 5例 ,膀胱部分切除 18例 ,膀胱部分切除加前列腺切除 7例。术后 10～ 14天经尿管 (先排尽尿液 )行膀胱灌注 ,灌注液为 BCG12 0…     

自噬相关基因Beclin 1沉默对人肺癌A549细胞顺铂耐药性的影响

目的探讨应用RNAi技术沉默Beclin 1基因对人肺癌A549细胞顺铂(DDP)耐药性的影响。方法应用真核细胞转染技术将Psilencer 3.1-siRNA-Beclin 1重组质粒转入人肺癌DDP耐药A549/DDP细胞,通过RT-PCR和Western印迹检测Beclin-1基因表达,四甲基偶氮唑蓝(MTT)法检测细胞对DDP的耐药性及细胞增殖情况,流式细胞仪检测细胞凋亡。结果与空白对照组及空质粒对照组相比,重组质粒组Beclin 1mRNA及蛋白表达下降,凋亡率增加,对DDP的敏感性增加(均P<0.05)。结论 Psilencer 3.1-siRNA-Beclin 1转染人肺癌A549细胞后,可有效抑制Beclin-1基因的表达,增加人肺癌A549细胞对DDP的敏感性,促进细胞凋亡。     

miR-485-5p对结肠癌细胞顺铂耐药的影响

目的:探讨miR-485-5p通过PI3K/Akt-PAK1信号通路对结肠癌细胞顺铂耐药的影响。方法:构建LoVo/DDP细胞株,将建LoVo/DDP细胞株分为NC组(未做转染处理)、miR-485-5p mimics组(转染miR-485-5p mimics)、miR-485-5p inhibitors组(转染miR...     

RNA干扰Ref-1表达对肝癌顺铂敏感性的影响

目的建立表达氧化还原因子-1（Ref-1）小分子干扰RNA的重组逆转录病毒载体pmscv/siRef-1,观察人肝癌细胞株HepG2下调内源性Ref-1后对顺铂的敏感性变化。方法采用基因重组技术构建逆转录病毒载体pmscv/siRef-1。包装逆转录病毒,感染HepG2。RT-PCR及Western blot法检测感染后细胞内Ref-1 mRNA和蛋白表达,MTT法检测HepG2细胞下调Ref-1表达后对顺铂的敏感性变化。结果pmscv/siRef-1能有效被包装并感染靶细胞,感染pmscv/siRef-1病毒的HepG2细胞Ref-1蛋白与mRNA表达量明显降低,细胞对顺铂敏感性显著增加（P〈0.05）。结论成功构建以逆转录病毒为基础的抑制内源性Ref-1表达的RNA干扰载体;RNA干扰Ref-1基因可显著提高HepG2细胞对顺铂的敏感性。     

切除修复交叉互补基因1、生存素与顺铂耐药的研究进展

顺铂耐药有多种复杂机制参与,大量研究表明DNA修复途径的关键基因切除修复交叉互补基因1和参与细胞凋亡和有丝分裂调控的生存素基因与顺铂耐药密切相关.     

顺铂对人结直肠癌细胞HCT-116中TOB1表达的影响

目的探讨顺铂对人结直肠癌细胞株HCT-116中TOB1的表达水平和细胞内分布的影响。方法采用RT-PCR和Western印迹法实验检测不同剂量顺铂处理后HCT-116细胞中TOB1 mRNA及蛋白表达水平的变化;采用同样的方法检测顺铂处理后不同时间TOB1 mRNA及蛋白表达水平的变化;同时采用免疫荧光实验检测顺铂对TOB1在细胞内分布的影响。结果 HCT-116细胞在不同剂量顺铂处理24 h后,TOB1 mRNA及蛋白的表达水平均明显增加,并存在一定的剂量依赖性;不同处理时间检测发现TOB1 mRNA及蛋白的表达水平在顺铂处理后2 h即明显升高,24 h后仍保持较高的表达水平;免疫荧光实验发现HCT-116细胞中TOB1主要分布在细胞质,而顺铂处理2 h后HCT-116细胞中TOB1即向细胞核内转位。结论顺铂诱导人类结直肠癌细胞株HCT-116中TOB1 mRNA及蛋白的表达增加,同时诱导TOB1向细胞核内转位,提示TOB1作为临床结直肠癌化疗靶基因的可能,对临床用药以及疗效的判断具有一定的指导作用。     

小分子干扰RNA沉默结缔组织生长因子对鼠肝星状细胞培养激活的影响

目的研究化学合成小分子干扰RNA(siRNA)对大鼠原代肝星状细胞(HSC)结缔组织生长因子(CTGF)基因表达的阻抑作用及对HSC培养激活的影响。方法以胶原酶原位灌注消化加密度梯度离心法分离大鼠原代HSC,将siRNA以脂质体包裹,转染培养72h的原代HSC,设空白对照,收集孵育96h细胞,以Westernblot和免疫细胞化学染色法检测原代HSCCTGF及α-平滑肌肌动蛋白(α-SMA)基因表达。结果转染siRNA的原代HSCCTGF及α-SMA基因表达显著下调,与对照相比,CTGF蛋白下调(92±5)%(P<0.01);α-SMA蛋白表达分别下调(62±9)%(P<0.01,Westemblot方法)和(58±6)%(P<0.01,免疫细胞化学染色法)。结论siRNA能显著下调大鼠原代HSCCTGF基因表达,明显阻抑原代HSC培养激活,提示针对CTGF基因化学合成的siRNA具有防治肝纤维化的潜力。     

Effect of silencing Bcl-2 expression by small interfering RNA on radiosensitivity of gastric cancer BGC823 cells

ObjectiveTo explore the influence of silencing Bcl-2 expression by small interfering RNA (siRNA) on Bcl-2 protein expression, cell apoptosis rate and radiosensitivity of gastric cancer BGC823 cells.MethodssiRNA segment for Bcl-2 gene was designed and synthesized, then was induced into gastric cancer BGC 823 cells by liposome transfection. Bcl-2 protein expression was detected by Western Blotting. After X radiation, flow cytometry and clone forming assay were used to determine the effects of RNA interference on BGC823 cell apoptosis rate and radiosensitivity.ResultAfter the transfection of Bcl-2 siRNA, the positive expression rate of Bcl-2 protein in BGC823 cells was (35.45±2.35)%. Compared with the control group and negative siRNA transfection group, the rate was significantly decreased (P<0.01). The apoptosis rate of BGC823-RNAi cell was (10.81±0.91)%, which was significantly higher than the control group and negative siRNA transfection group (P<0.01). After 48h X radiation, the apoptosis rate of BGC823-RNAi was (28.91±1.40)%, which was significantly higher than the control group and the group without radiation (P<0.01). During clone forming assay D₀, D_q and SF₂ values in Bcl-2 siRNA1 transfection group were all lower than those in the control group. The radiosensitivity ratio was 1.28 (the ratio of D₀) and 1.60 (the ratio of D_q).ConclusionsSpecific siRNA of Bcl-2 gene can effectively inhibit the expression of Bcl-2 gene, enhance the radiosensitivity and apoptosis of gastric cancer BGC823 cells, having good clinical application perspective.     

Inhibitory effect of vascular endothelial growth factors-targeted small interfering RNA on proliferation of gastric cancer cells

AIM： To examine the effects of vascular endothelial growth factor （VEGF）-targeted small interfering RNA （siRNA） on proliferation of gastric cancer cellsin vitro.
METHODS： Several siRNAs were transfected into human gastric cancer cell line SGC-7901 with Lipofectamine 2000. Cells not transfected with LipofectamineTM 2000 or scrambled （SCR） siRNA served as controls. The inhibitory effect of siRNA on the expression of VEGF mRNA and protein was detected by RT-PCR and ELISA. MTT assay was used to examine the inhibition rate of cell growth.The change in cell cycling of siRNA-treated cells was detected by flow cytometry.
RESULTS： siRNA targeting human VEGF effectively inhibited the proliferation of gastric cancer cell lineSGC-7901 and the distribution of cell cycle. The percentage of G0/G1 phase was significantly higher in siRNA1- and siRNA2-transfected cells than in control cells.The expression of VEGF mRNA was significantly inhibited in siRNA1- and siRNA2-transfected cells compared with that in control cells. VEGF protein notably decreased in siRNA-transfected cells, but had no effect on SCR siRNA.
CONCLUSION： VEGF siRNA inhibits proliferation of gastric cancer cells in vitro.     

siRNA在实验性急性肝衰竭中的治疗作用研究进展

RNA干扰(RNA interference,RNAi)是指导入特异性针对目标基因的同源双链RNA,引起目标基因的不表达或减效表达.小干扰RNA(small interfering RNA或shortinterfering RNA,siRNA)是RNAi发挥作用的重要中间效应分子[1].siRNA具有潜在的临床治疗应用前景,目前至少有5种siRNA药物已进入临床试验[2].     

Small interfering RNA against the apurinic or apyrimidinic endonuclease enhances the sensitivity of human pancreatic cancer cells to gemcitabine in vitro

OBJECTIVE: To investigate whether the downregulation of human apurinic or apyrimidinic endonuclease/redox factor-1 gene (APE1/Ref-1) expression by ribonucleic acid interference (RNAi) would increase the sensitivity of SW1990 cells to gemcitabine. METHODS: Chemically synthesized small interfering RNA (siRNA) directed against human APE1/Ref-1 (si-APE1) was transfected into SW1990 cells through transfection reagents. The mRNA expression of APE1/Ref-1 was detected by semi-quantitative RT-PCR and the protein expression of APE1/Ref-1 was detected by Western blot; cell proliferation and apoptosis were studied by a Cell Counting Kit 8 (CCK-8) and flow cytometry (FCM) and fluorescence microscopy. RESULTS: After transfecting the SW1990 cells with siRNA directed against human APE1/Ref-1, the mRNA expression of APE1/Ref-1 of these cells was reduced, and its protein expression was reduced by 55.41 ± 3.58%. The CCK-8 assay showed that the absorbance and the inhibition of cell growth transfected with si-APE1 were significantly different from the blank (cultured with Dulbecco's modified Eagle's medium) and negative control (given 50 nmol/L scrambled control siRNA). The inhibition rates of cell growth of the si-APE1 group at 24, 48, 72 h were 41.69 ± 2.78%, 24.83 ± 3.70% and 21.27 ± 9.82%, respectively. A FCM analysis and cell morphology study showed that the apoptotic rate of SW1990 cells transfected with si-APE1 combined with gemcitabine treatment was significantly different from the blank control and others. CONCLUSION: To knock down APE1/Ref-1 gene expression may significantly sensitize the SW1990 cells to gemcitabine and enhance cell apoptosis.     

支架蛋白RACK1小干扰RNA抑制卵巢癌细胞CAOV3的增殖、迁移和侵袭

目的观察支架蛋白RACK1小干扰RNA(siRNA)对卵巢癌CAOV3细胞增殖、迁移和侵袭的影响和基质金属蛋白酶(MMP)-2和MMP-9的表达变化。方法体外培养CAOV3细胞,实验分scramble siRNA组和RACK1 siRNA组;Lipofectamine 2000转染CAOV3细胞,Western印迹检测RACK1的干涉效能;MTT法测定CAOV3细胞的增殖率;划痕实验和transwell迁移和侵袭实验研究RACK1对细胞体外增殖、迁移和侵袭运动能力的影响;Western印迹检测CAOV3细胞中MMP-2和MMP-9蛋白表达。结果与scramble siRNA组比较,RACK1 siRNA组RACK1的蛋白表达水平降低,明显抑制CAOV3细胞的增殖、迁移和侵袭,降低MMP-2和MMP-9蛋白表达。结论下调RACK1表达可抑制卵巢癌细胞CAOV3的增殖、迁移和侵袭,其机制可能与改变MMP-2和MMP-9蛋白表达相关。     

靶向Akt1的小分子干扰RNA对人胃癌细胞系SGC7901生长抑制的体外研究

目的研究靶向Akt1小分子RNA对SGC7901胃癌细胞的增殖和侵袭的抑制作用。方法通过构建人Akt1特异性siRNA并转染SGC7901胃癌细胞,应用Western blot和realtime PCR检测了Akt1-siRNA的敲低效果;流式细胞术及Transwell试验等方法分析对增殖、侵袭、凋亡的影响。结果Akt1-siRNA可以下调Akt1的表达,并且下调Akt1后细胞的增殖活性明显受到抑制;细胞周期在G0/G1期有明显的阻滞(χ2=11.076,P=0.026);早期凋亡的细胞明显增多(F=89.386,P=0.00);肿瘤细胞的侵袭性生长受到了抑制(F=21.351,P=0.00)。结论靶向人Akt1的siRNA可以特异性的抑制Akt1的表达,进而抑制细胞的生长,siRNA可以成为胃癌靶向治疗的一种新的策略。     

Inhibiting HIV-1 infection in human T cells by lentiviral-mediated delivery of small interfering RNA against CCR5

Double-stranded RNAs approximately 21 nucleotides long [small interfering RNA (siRNA)] are recognized as powerful reagents to reduce the expression of specific genes. To use them as reagents to protect cells against viral infection, effective methods for introducing siRNAs into primary cells are required. Here, we describe success in constructing a lentivirus-based vector to introduce siRNAs against the HIV-1 coreceptor, CCR5, into human peripheral blood T lymphocytes. With high-titer vector stocks, >40% of the peripheral blood T lymphocytes could be transduced, and the expression of a potent CCR5-siRNA resulted in up to 10-fold inhibition of CCR5 expression on the cell surface over a period of 2 weeks in the absence of selection. In contrast, the expression of another major HIV-1 coreceptor, CXCR4, was not affected. Importantly, blocking CCR5 expression by siRNAs provided a substantial protection for the lymphocyte populations from CCR5-tropic HIV-1 virus infection, dropping infected cells by 3- to 7-fold; only a minimal effect on infection by a CXCR4-tropic virus was observed. Thus, our studies demonstrate the feasibility and potential of lentiviral vector-mediated delivery of siRNAs as a general means of intracellular immunization for the treatment of HIV-1 and other viral diseases.