组蛋白去乙酰化酶抑制剂提高腺病毒对K562细胞转染及杀伤效率的研究

 目的　研究通过观察组蛋白去乙酰化酶（histone deacetylase,HDAC）抑制剂曲古抑菌素A（trichostatin A,TSA）对人类白血病细胞系K562 CAR表达水平的影响,并探讨HDAC抑制剂在以腺病毒为载体的基因治疗中的应用价值。方法　在mRNA和蛋白水平检测TSA处理K562细胞前后CAR的表达情况,采用流式细胞术测定病毒的转染效率,四甲基偶氮唑蓝（MTT）法检测腺病毒及其携带的基因的体外抗瘤效应。结果　TSA处理后,K562细胞CAR 的mRNA 和蛋白表达明显增高;流式细胞仪分析ADV-GFP转染K562 后GFP的表达发现：未处理组的转染率为（8.74±0.34）％,1、10 和100 nmol／L TSA处理细胞48 h后的转染率分别为（12.26±0.55）％、（20.83±1.22）％和（28.66±0.43）％。未处理组与处理组间及各处理组间转染效率的差异有统计学意义（P＜0.05）。MTT结果表明腺病毒M1介导的体外杀伤效应TSA处理组比未处理组增强（P＜0.05）,TSA各处理组间的体外杀伤效应随TSA浓度的提高而增强（P＜0.05）。结论　低浓度的TSA可以增强腺病毒对K562细胞的感染及杀伤效率,可以提高以腺病毒为载体的血液肿瘤基因治疗的疗效。     

PTEN基因增强卵巢癌A2780细胞对紫杉醇敏感性的研究

背景与目的:近来的研究表明PTEN基因(phosphatase and tensin homology deleted on chromosome ten,第10号染色体上磷酸酶和张力蛋白同源缺失的基因)失活在肿瘤化疗耐药发挥了重要作用。本文研究外源性PTEN基因稳定转染人卵巢癌A2780细胞后对紫杉醇敏感性的影响。方法:将野生型PTEN基因真核表达质粒在脂质体介导下转染人卵巢癌A2780细胞,同时以转染空载体和未转染细胞作为对照(3组细胞分别命名为WT-PTEN/A2780,GFP/A2780和A2780),分别应用RT-PCR和蛋白印迹技术检测各组细胞PTEN mRNA转录和蛋白表达的变化;四甲基偶氮唑蓝实验观察转染PTEN基因对肿瘤细胞生长的抑制作用和A2780细胞对紫杉醇药物敏感性的影响,流式细胞仪(FACS)分析细胞凋亡情况。结果:与对照组相比,转染野生型PTEN基因能明显增加A2780细胞PTENmRNA转录和蛋白的表达,差异有显著性(P<0.05);MTT法显示,WT-PTEN/A2780细胞生长明显慢于GFP/A2780和A2780细胞;紫杉醇对WT-PTEN/A2780,GFP/A2780和A2780的IC50值分别为(7.6±0.40)nmol/l、(22.5±0.9)nmol/l和(22.7±0.8)nmol/l,WT-PTEN/A2780细胞对紫杉醇药物敏感性显著增加(P<0.05);FACS分析显示,紫杉醇作用24h后,WT-PTEN/A2780,GFP/A2780和A2780的凋亡率分别为(34.6±1.6)%、(13.5±0.9)%和(12.7±1.0)%,差异有显著性(P<0.05)。结论:转染野生型PTEN重组质粒能有效提高A2780细胞内PTEN的表达,诱导A2780细胞凋亡,显著增加A2780细胞对紫杉醇杀伤的敏感性。     

真核表达survivin基因对曲古菌素A诱导卵巢癌细胞凋亡作用的影响

目的　探讨survivin 基因对曲古菌素A( TSA) 诱导卵巢癌细胞凋亡作用的影响。方法　(1) 将本实验室已构建成功的survivin 正义全长真核表达质粒(pcDNA 3. 1-urvivin) ,经脂质体包裹转染人卵巢癌细胞A2780 ,以转染pcDNA 3. 1空载体的A2780 细胞为对照。(2) RT2PCR 和Western blot 方法分别检测survivin mRNA 和蛋白质的表达。(3) MTT 比色法和流式细胞仪(FACS) 分别检测TSA 对两组细胞存活率和凋亡率的影响。(4) Western blot 检测TSA 作用下A2780 细胞中survivin 蛋白的表达变化。结果　(1) RT-PCR和Western blot 检测提示转染pcDNA 3. 1-urvivin 组中survivin mRNA 和蛋白质表达明显高于空载体组。(2) MTT 比色法和FACS 检测提示转染pcDNA 3. 1-urvivin 组细胞存活率明显高于空载体组,细胞凋亡率明显低于空载体组,差异有统计学意义( P<0. 05) 。pcDNA 3. 1-urvivin转染后的2780 细胞对TSA 的敏感性明显降低。(3) Western blot 检测提示survivin 的表达水平随着TSA 作用时间的延长而下降。结论　曲古菌素A 诱导卵巢癌细胞的凋亡作用可能与survivin 基因表达有关。     

CAR抑制卵巢癌细胞株SKOV3侵袭转移表型的研究

背景与目的:柯萨奇-腺病毒受体(coxsackieandadenovirusreceptor,CAR)最早作为2,5型腺病毒的受体而被人们发现和认识,近年的研究发现它还是粘附分子家族的一员,并参与肿瘤恶性表型改变。本研究通过转染真核表达载体,探讨其对卵巢癌细胞株SKOV3侵袭转移表型的影响。方法:利用Westernblot和RT-PCR检测4株卵巢癌细胞CAR的表达;脂质体介导转染含有全长CAR基因的真核表达质粒至SKOV3细胞,经G418筛选出稳定表达的阳性细胞克隆;体外粘附实验及软琼脂克隆形成实验验证CAR对SKOV3侵袭转移表型的影响。结果:4株卵巢癌细胞中,CAR表达水平不同程度下调,其中SKOV3细胞CAR表达缺失。转染后,SKOV3细胞CARmRNA和蛋白质水平表达均明显增高;细胞间粘附力明显增强;软琼脂克隆实验显示转染细胞每孔克隆形成数(25.3±8.9)明显低于未转染组(88.8±14.0)和转染空质粒组(82.5±19.4)。结论:外源性CAR基因的导入可以增强卵巢癌细胞SKOV3间的粘附性,从而抑制肿瘤细胞的侵袭转移表型。     

mdr1启动子调控CD::UPP基因对紫杉醇耐药卵巢癌细胞的杀伤作用

目的探讨腺病毒介导的mdr1启动子调控胞嘧啶脱氨酶尿嘧啶磷酸核糖转移酶(CDUPP)融合基因联合5-氟胞嘧啶(5-FC)对紫杉醇耐药卵巢癌细胞的特异性杀伤作用.方法扩增、纯化含有mdr1-CDUPP基因的重组腺病毒,转染人卵巢癌紫杉醇耐药细胞株A2780/Taxol和亲本细胞株A2780,RT-PCR检测mdr1和CDUPP基因的表达水平;之后加入5-FC,MTT法检测细胞抑制情况及旁观者效应,并观察腺病毒转染后裸鼠移植瘤的生长情况.结果mdr1和CDUPP基因在A2780/Taxol细胞中可稳定表达,转染后A2780/Taxol组的细胞生长明显低于A2780组;转基因的A2780/Taxol细胞联合5-FC后可通过旁观者效应杀伤周围未转基因的耐药细胞;耐药组移植瘤生长明显受到抑制,肿瘤体积为(569.10±187.93)mm3,对照组肿瘤体积为(2 111.98±230.82)mm3,差异有统计学意义(P＜0.01).结论mdr1启动子可调控CDUPP基因特异性表达并特异性杀伤紫杉醇耐药卵巢癌细胞.     

第10号染色体上磷酸酶和张力蛋白同源缺失的基因对人卵巢癌A2780细胞侵袭和迁移能力的影响及相关机制

目的 探讨第10号染色体上磷酸酶和张力蛋白同源缺失的基因(PTEN)对人卵巢癌A2780细胞侵袭和迁移能力的影响及相关机制.方法 将携带外源性人PTEN基因的野生型质粒(WT-PTEN)和磷酸酶域突变型质粒(C124A-PTEN)转入人卵巢癌细胞株A2780中,利用Transwell小室法和划痕愈合实验检测转染前后细胞侵袭和迁移能力的变化,应用Western blot检测各组细胞PTEN及其下游相关蛋白表达的变化.以空载体质粒和未转染细胞作为对照.结果 细胞侵袭实验显示,WT-PTEN/A2780、C124A-PTEN/A2780、GFP/A2780和A2780细胞穿透Matrigel胶的细胞数,分别为(24.3±2.5)个、(43.7±3.8)个、(44.7±2.1)个和(45.0±3.0)个,WT-PTEN/A2780细胞的穿膜数明显少于其他各组(P＜0.05).划痕愈合实验显示,WT-PTEN/A2780、C124A-PTEN/A2780、GFP/A2780和A2780细胞的迁移距离分别为(54.1±3.7)μm、(78.7±3.4)μm、(78.1±3.1)μm和(76.8±3.5)μm,WT-PTEN/A2780细胞的迁移速度明显慢于C124A-PTEN/A2780、GFP/A2780和A2780细胞(P＜0.05).WT-PTEN/A2780细胞中基质金属蛋白酶9(MMP-9)蛋白的表达明显低于C124A-PTEN/A2780、GFP/A2780和A2780细胞(P＜0.05).结论 野生型PTEN可有效抑制A2780细胞的侵袭和迁移,该抑制作用与A2780细胞中MMP-9表达下调有关.

Abstract：

Objectiye To evaluate the effects of PTEN on invasive and migration ability of human ovarian cancer cell line A2780 and related mechanisms. Methods The plasmid including WT-PTEN and mutant PTEN were transferred into A2780 cells. The invasive and migration ability were measured before and after transfection by transwell chamber and wound-healing assays. The expression of PTEN protein and related proteins in the cells were detected by Western blot analysis. Empty plasmid-transfected A2780 and normal A2780 cells were used as control (the different four groups were named as WT-PTEN/A2780,C124A-PTEN/A2780, GFP/A2780 and A2780 ). Results The number of penetrating cells was significantly less in WT-PTEN/A2780 cells(24.3 ± 2.5 ) than those in C124A-PTEN/A2780, GFP/A2780 and A2780 cells (43.7 ± 3.8, 44.7 ± 2. 1 and 45.0 ± 3.0 ) ( P ＜ 0.05 ). The migration distance was markedly shorter in WT-PTEN/A2780 cells (54.1 ± 3.7) than those in C124A-PTEN/A2780, GFP/A2780 and A2780 cells (78.7 ± 3.4, 78.1 ± 3.1 and 76.8 ± 3.5 ) ( P ＜ 0. 05 ). Conclusions Transfection with PTEN may suppress the invasive and migration ability of ovarian cancer cell line A2780 depending on its phosphatase activity, and the suppressive effect may be due to the down-regulation of MMP-9 in the cancer cells.     

mdr1启动子调控CD∷UPP基因对紫杉醇耐药卵巢癌细胞的杀伤作用

目的:探讨腺病毒介导的mdr1启动子调控胞嘧啶脱氨酶∷尿嘧啶磷酸核糖转移酶(CD∷UPP)融合基因联合5-氟胞嘧啶(5-FC)对紫杉醇耐药卵巢癌细胞的特异性杀伤作用。方法:扩增、纯化含有mdr1-CD∷UPP基因的重组腺病毒,转染人卵巢癌紫杉醇耐药细胞株A2780/Taxol和亲本细胞株A2780,RT-PCR检测mdr1和CD∷UPP基因的表达水平;之后加入5-FC,MTT法检测细胞抑制情况及旁观者效应,并观察腺病毒转染后裸鼠移植瘤的生长情况。结果:mdr1和CD∷UPP基因在A2780/Taxol细胞中可稳定表达,转染后A2780/Taxol组的细胞生长明显低于A2780组;转基因的A2780/Taxol细胞联合5-FC后可通过旁观者效应杀伤周围未转基因的耐药细胞;耐药组移植瘤生长明显受到抑制,肿瘤体积为(569.10±187.93)mm3,对照组肿瘤体积为(2111.98±230.82)mm3,差异有统计学意义(P<0.01)。结论:mdr1启动子可调控CD∷UPP基因特异性表达并特异性杀伤紫杉醇耐药卵巢癌细胞。     

组蛋白去乙酰化酶抑制剂协同紫杉醇对人肺癌细胞株抑制作用及机制

背景与目的:组蛋白去乙酰化酶(histone deacetylase,HDAC)抑制剂通过抑制多种基因或蛋白介导的信号转导网络的功能,影响细胞增殖及对化疗药物的敏感性。HDAC抑制剂可能会提高紫杉醇对肺癌细胞的抑制作用。本研究评价HDAC抑制剂曲古抑菌素A(trichostatin A,TSA)协同紫杉醇抑制肺癌细胞H322及H1299的作用及机制。方法:将H322和H1299细胞分别分成4组:(1)对照组;(2)紫杉醇组(TAX);(3)TSA组;(4)以TSA预先作用12h后,再使用紫杉醇的联合用药组(TF)。分别以MTT法、流式细胞术检测细胞增殖情况以及细胞周期、细胞凋亡等指标的变化,荧光显微镜观察细胞核形态的改变,Western blot检测Survivin、PARP蛋白及细胞外信号调节激酶(ERK)的表达。结果:TSA明显增强了紫杉醇对两种肺癌细胞的抑制率。紫杉醇作用96h对H322细胞的IC50由(48.07±26.12)nmol/L下降至(6.34±5.72)nmol/L,对H1299细胞的IC50由(110.6±38.7)nmol/L下降至(63.7±11.8)nmol/L,差异具有统计学意义...     

PTEN基因转染对卵巢癌A2780细胞周期和增殖能力影响的研究

目的:研究外源性PTEN基因稳定转染对人卵巢癌A2780细胞周期和增殖能力的影响。方法:构建PTEN基因的野生型真核表达质粒pEGFP-C1-WT-PTEN和突变型表达质粒pEG-FP-C1-C124A-PTEN,以脂质体介导法转染体外培养的人卵巢癌细胞株A2780,同时转染空载体pEGFP-C1质粒,以未转染细胞为对照(转染成功后分别命名为WT-PTEN/A2780组、C124A-PTEN/A2780组、pEGFP-C1/A2-780组和A2780组。应用RT-PCR、Western blot方法分析目的基因及其蛋白表达,并采用MTT法和流式细胞术检测细胞增殖和细胞周期。结果:与对照细胞相比,WT-PTEN/A2780组和C124A-PTEN/A2780组PTEN mRNA及PTEN蛋白出现明显的高表达,与对照组细胞相比差异有统计学意义(t=5.300,P=0.034;t=11.963,P=0.007;t=7.869,P=0.016;t=22.421,P=0.002);WT-PTEN/A2780组细胞生长速度明显慢于未转染A2780细胞,然而C124A-PTEN/A2780组和pEGFP-C1/A2780组细胞生长速度无明显变化。流式细胞术显示WT-PTEN/A2780细胞G1期细胞数增加到(71.18±4.34)%,S期细胞数变为(17.48±1.96)%,与对照组相比差异有统计学意义(t=19.508,P=0.003;t=25.354,P=0.002),提示从G1期到S期发生抑制。结论:野生型PTEN可依赖其磷酸酶活性使A2780细胞在G1/S期发生细胞周期阻滞,并抑制A2780细胞增殖。     

抑癌基因OVCA1体外对卵巢癌细胞A2780迁移和侵袭的抑制作用

目的:探讨卵巢癌基因1[ovarian cancer gene 1,OVCA1;也称为DPH2L( diphthamide synthesis protein 2-like)基因]体外对卵巢癌细胞系A2780迁移和侵袭能力的抑制作用.方法:采用脂质体法将GFP标记的携带OVCA1的重组质粒pEGFP-OVCA1或GFP空白质粒分别转染A2780细胞后,G418筛选稳定转染细胞,有限稀释法筛选稳定转染细胞的单克隆细胞株,荧光显微镜检查绿色荧光蛋白的表达及RT-PCR方法检测A2780细胞OVCA1基因mRNA的表达.A2780-OVCA1细胞为实验组, A2780-GFP细胞和A2780细胞为对照组,采用划痕实验、Transwell体外迁移实验和Matrigel体外侵袭实验检测OVCA1对A2780细胞迁移和侵袭能力的影响.结果:重组质粒pEGFP-OVCA1转染后获得了稳定表达GFP标记OVCA1蛋白的A2780细胞株.A2780-OVCA1组划痕后的细胞迁移速度明显小于两对照组(P<0.05);A2780-OVCA1组穿过Transwell滤膜的迁移细胞数明显少于两对照组(P<0.05);A2780-OVCA1组穿过Matrigel滤膜的侵袭细胞数明显少于两对照组(P<0.05).结论:OVCA1在体外具有显著抑制卵巢癌A2780细胞迁移和侵袭的作用.     

两位点短发卡状RNA诱导AKT2基因沉默在卵巢癌细胞紫杉醇敏感性中的应用研究

目的：探讨AKT2基因在肿瘤细胞对紫杉醇敏感性中的作用。方法：分别构建2个针对同一AKT2基因不同位点的短发卡状RNA（shRNA）载体，转染人卵巢癌细胞A2780、SKOV3，荧光显微镜观察细胞内荧光蛋白的表达及转染效率，运用RT—PCR、蛋白质免疫印迹（western blotting）方法比较单独转染的抑制瘤和共转染对AKT2表达的沉默效率；抑制AKT2表达后，流式细胞仪（FACS）检测肿瘤细胞对紫杉醇的敏感性。结果：构建的2种shRNA表达载体均可抑制AKT2mRNA和蛋白的表达，共转染的抑制率明显高于分别单独转染的抑制率（P〈0．05）；FACS结果显示，共转染沉默AKT2基因后，细胞凋亡率明显增加（P〈0．05）。结论：共转染针对AKT2基因不同位点的2个shRNA真核表达载体，对AKT2基因的抑制效率高于单独转染1个载体；抑制卵巢癌细胞中AKT2基因表达，能增强其对紫杉醇的敏感性。     

Deletion of the intracellular domain of coxsackie and adenovirus receptor (CAR) enhances the expression of itself and boosts the efficiency of current adenovirus-mediated gene therapy in ovarian cancer cell lines in vitro

The failure of adenovirus-mediated gene therapy often derives from the absence of coxsackie and adenovirus receptor (CAR) expression in target cells. We hypothesize that the slight up-regulation of CAR expression might boost the effect of adenovirus-mediated gene therapy in ovarian cancer. To test this hypothesis, we transfected full-length and intracellular-domain-deleted (tailless) CAR plasmids into CAR-deficient ovarian cancer cell line SKOV3. We observed significant elevations of the in vitro killing effect of Adv-TK and oncolytic adenovirus-mediated cytopathic effect (CPE) in transfected sub-clones, and tailless-transfected SKOV3 showed higher CAR expressions than full-length CAR-transfected cells. We conclude that the extracellular domain of CAR is essential for adenovirus-based gene therapy and, furthermore, that its intracellular domain might play an important role in the regulation of its own expression.     

短发卡状RNA抑制AKT2基因表达增强卵巢癌细胞对紫杉醇敏感性的研究

目的：构建AKT2基因特异性短发卡状RNA（shRNA）真核表达载体,观察RNA干扰（RNAi）技术,对人卵巢癌A2780和SKOV3细胞中AKT2蛋白激酶表达的抑制作用,并探讨其促进细胞凋亡的机制。方法：运用基因工程技术,设计合成针对AKT2mRNA的特异性shRNA,构建真核表达载体pAKT2-shRNA。将pAKT2-shRNA经脂质体（Lipofectamine^TM 2000）包裹转染人卵巢癌A2780和SKOV3细胞,荧光显微镜观察细胞内DsRed红色荧光蛋白的表达,计算转染效率,半定量RT—PCR（Semi-quantitative RT-PCR）、蛋白质免疫印迹（Western blot）检测AKT2的表达及干扰效率,流式细胞学检测法（FACS）检测细胞凋亡率,比较抑制AKT2基因前后卵巢癌细胞抵抗凋亡能力。结果：成功构建了PAKT2-ShRNA载体。A2780和SKOV3细胞转染pAKT2-shRNA后,荧光显微镜下观察转染效率约40％;Semi-quantitative RT-PCR和Western blot检测结果示,转染后AKT2 mRNA和蛋白表达均显著降低。FACS检测结果显示,转染pAKT2-shRNA后,紫杉醇25nmol／L处理细胞12h,与空白对照组和阴性对照组相比,细胞凋亡率显著增加,P〈0．05。结论：构建的pAKT2-shRNA真核表达载体能有效抑制AKT2基因表达;运用RNAi技术,降低卵巢癌细胞中AKT2基因表达水平,能增强肿瘤细胞对化疗药物的敏感性,促进肿瘤细胞凋亡。     

TSA联合基因工程腺病毒H101治疗食管癌皮下移植瘤的研究

目的 研究曲古霉素A(TSA)对基因工程腺病毒H101杀伤食管癌EC9706细胞作用的影响,探讨HDAC抑制剂在腺病毒载体基因治疗中应用的可能性和作用机制.方法1)先成瘤后治疗组,构建裸鼠食管癌移植瘤模型,待肿瘤长至肉眼可见的肿块(约8mm ×7mm)后分组.TSA治疗组:每只每次瘤内注射1.0 μmol/L TSA;...     

Reduced expression of coxsackievirus and adenovirus receptor (CAR) in tumor tissue compared to normal epithelium in head and neck squamous cell carcinoma patients

Even though adenoviral vector is widely used in gene therapy of squamous cell carcinoma of the head and neck (SCCHN), the expression level of Coxsackievirus and adenovirus receptor (CAR) in SCCNH is not clearly defined. To identify this variability, the expression of CAR was measured using SCCHN cell lines and compared with transfection efficiency. It was found by RT-PCR and Western blot analysis that CAR levels varied in SCCHN cell lines. FACS analysis and adenovirus infection assay revealed that there was a good correlation between the level of CAR expression and the transfection efficiency. To identify the actual CAR expression patterns of human SCCHN tissues in vivo, immunohistochemical staining was undertaken on frozen biopsies of six SCCHN patients. In all the patients examined, the normal tissues showed much stronger staining for CAR than the tumor tissues. These results demonstrate that the level of CAR expression of a tumor should be evaluated before clinical application of adenoviral vector for gene therapy in SCCHN.     

Overexpression of protein kinase A - RIalpha reduces lipofection efficiency of cisplatin-resistant human tumor cells

Cisplatin-resistant variant A2780CP/vector cells were 4.0-5.3-fold more transfectable and 7.6-fold more resistant to cisplatin than their parent cisplatin-sensitive human ovarian carcinoma A2780/vector cells. Overexpression of cAMP-dependent protein kinase Type I regulatory alpha subunit (PKA-RIalpha) gene in A2780CP cells significantly reduced (maximum 47.0%) the transfection activity, with a slight reduction (maximum 27.3%) of cisplatin resistance, of A2780CP cells. However, RIalpha-overexpressing A2780CP (A2780CP/RIalpha) cells were still 2.5-to 3.0-fold more transfectable and 5.5-fold more resistant to cisplatin than A2780 cells. This results suggest that gene transfer efficiency is associated with cisplatin resistance, in part, through the PKA-mediated cAMP signal transduction pathway.     

PI-3K/Akt抑制剂LY294002对卵巢癌细胞A2780/Taxol多药耐药性的逆转作用

背景与目的:磷脂酰肌醇(phosphatidylinositol 3 kinase,PI-3K)可抑制细胞凋亡,对PI-3K抑制剂的研究可以更好地了解PI-3K的促癌机制,为多种癌症如卵巢癌、乳腺癌等的基因治疗提供线索。本研究目的在于探讨PI-3K/Akt信号通路抑制剂LY294002对卵巢癌耐紫杉醇细胞株A2780/Taxol多药耐药的逆转作用。方法:用LY294002处理A2780/Taxol细胞,流式细胞术检测细胞凋亡,MTT法检测细胞对紫杉醇的药物敏感性,RT-PCR检测MDR1mRNA的表达,Western blot方法分析LY294002作用前后磷酸化Akt及P-gp蛋白的表达。结果:10和50μmol/L LY294002干预A2780/Taxol细胞24h后,A2780/Taxol细胞凋亡率分别为(8.84±1.65)%和(20.78±2.47)%,显著高于未干预细胞的凋亡率(1.25±0.78)%(P<0.05);A2780/Taxol细胞对紫杉醇的半数抑制浓度(IC50)显著降低(P<0.01),相对逆转效率最高可达(78.08±0.37)%;MDR-1mRNA、磷酸化Akt及P-gp蛋白均明显降低。结论:PI-3K/Akt信号通路的激活与卵巢癌细胞多药耐药的产生有关,PI-3K/Akt抑制剂LY294002可逆转卵巢癌细胞A2780/Taxol的多药耐药。     

Silencing of Twist Expression by RNA Interference Suppresses Epithelial-mesenchymal Transition,Invasion, and Metastasis of Ovarian Cancer

Purpose: This study aimed to explore the role of the Twist gene in the epithelial-mesenchymal transition ofovarian cancer. Methods: An RNA interference plasmid expressing a small interfering RNA (siRNA)-targetingTwist (Twist siRNA vector) was designed, constructed, and transfected into the human ovarian cancer cell lineA2780. Transfection efficiency was assessed under a fluorescence microscope. Changes in the expression of TwistmRNA in A2780 after transfection with the pGenesil Twist shRNA plasmid were analyzed through RT-PCR.MTT assays and adhesion experiments were applied to determine changes in proliferation and adhesion abilityof A2870 after transfection with the Twist shRNA plasmid. Changes in the expression of the E-cadherin andN-cadherin proteins in A2780 after transfection with the Twist shRNA plasmid were analyzed using Westernblotting. Result: The restructuring plasmid pGenesil-Twist shRNA was constructed successfully. After 48 h ofculture, 80% of the cells expressed high-intensity GFP fluorescence and stability. The expression of Twist decreasedsignificantly after the transfection of the Twist shRNA plasmid (P<0.05). Proliferation of the transfected TwistshRNA cells showed no difference with that of the A2780-nontransfection or A2780-si-control groups (P>0.05) butthe adhesion ability of A2780 decreased dramatically (P<0.05). Expression of the E-cadherin protein increased,whereas that of the N-cadherin protein decreased compared with that in the A2780-nontransfection or A2780-si-control groups (P<0.05). Conclusion: Twist is essential for epithelial-mesenchymal transition, invasion, andmetastasis of ovarian cancer.