PTEN磷酸酶活性对乳腺癌细胞ZR-75-1迁移能力的影响

目的:探求PTEN蛋白的磷酸酶活性对乳腺癌细胞ZR-75-1转移能力的影响。方法:采用脂质体介导法分别将野生型PTEN质粒(wt-PTEN)、磷酸酶失活的PTEN质粒(G129R-PTEN)和只具有蛋白磷酸酶活性的PTEN质粒(G129E-PTEN)转染PTEN基因缺失的人乳腺癌细胞株ZR-75-1,Western印迹法检测PTEN蛋白及P397-FAK的表达水平,体外细胞划痕实验观察PTEN磷酸酶活性对ZR-75-1细胞迁移能力的影响,细胞基质黏附试验和人工重组基底膜侵袭试验测定PTEN质粒转染和未转染的ZR-75-1细胞的黏附抑制率和侵袭抑制率,免疫组化法检测MMP-2的水平。结果:wt-PTEN、G129R-PTEN及G129E-PTEN3种质粒均成功转染ZR-75-1细胞并有PTEN蛋白的表达,其中wt-PTEN、G129E-PTEN均能抑制ZR-75-1细胞迁移;wt-PTEN和G129E-PTEN转染细胞之间的黏附抑制率和侵袭抑制率或侵袭细胞相对数均无显著性差异,但与G129R-PTEN转染的和未经转染的ZR-75-1细胞相比有显著性差异(P<0.01)。wt-PTEN和G129E-PTEN质粒转染的ZR-75-1细胞其P397-FAK水平均显著低于G129R-PTEN质粒转染的ZR-75-1细胞;wt-PTEN与G129E-PTEN质粒转染的ZR-75-1细胞MMP-2水平对比于G129R-PTEN质粒转染的和未经质粒转染的ZR-75-1细胞有显著性差异(P<0.01)。结论:具有双特异磷酸酶活性的野生型PTEN基因和只具蛋白磷酸酶活性的PTEN基因均能抑制乳腺癌细胞ZR-75-1的迁移,而磷酸酶失活的PTEN基因则无此作用。     

乳腺癌细胞转染野生型PTEN质粒后转移能力的变化

 目的 研究抑癌基因PTEN对乳腺癌细胞转移的影响。方法 脂质体介导法将外源野生型抑癌基因PTEN转染入该基因缺陷的ZR-75-1乳腺癌细胞中，用嘌呤霉素筛选阳性克隆,Western- blot法检测PTEN蛋白表达；重组人工基底膜上检测黏附与侵袭能力。结果 转染后ZR-75-1乳腺癌细胞PTEN蛋白有明显表达；转染后ZR-75-1乳腺癌细胞侵袭抑制率与黏附抑制率分别达70.4 %和60.0 %。结论 PTEN基因对乳腺癌细胞转移具有一定的抑制作用；PTEN基因的缺失与否在一定程度上可以评价乳腺癌患者发生转移的危险程度。     

抑癌基因PTEN抑制乳腺癌ZR-75-1细胞转移作用机制的探讨

目的 探讨抑癌基因PTEN抑制乳腺癌细胞ZR-75-1转移的作用机制.方法 用脂质体介导法分别将野生型PTEN质粒(wt)、磷酸酶活性缺失的PTEN质粒(G129R)和只具蛋白磷酸酶活性的PTEN质粒(G129E)转染PTEN基因缺失的乳腺癌细胞ZR-75-1.转染细胞以嘌呤霉素筛选后,用PCR和Western-blot分别检测PTEN基因及其蛋白;通过黏附、侵袭实验,比较3种质粒转染细胞和未转染细胞之间的黏附、侵袭能力的差异;用Western-blot法检测各组转染细胞总的黏着斑激酶(FAK)和磷酸化黏着斑激酶(P397-FAK)的表达水平;以免疫组化法检测基质金属蛋白酶-2(MMP-2)和E-钙连素(E-Cd)的表达,并用RT-PCR检测各组转染细胞的p53mRNA水平.结果 3种质粒均成功转染ZR-75-1细胞,并证实3种转染细胞内均有PTEN基因存在及PTEN蛋白表达;wt、G129R、G129E等 3种质粒转染的细胞黏附抑制率分别为65.7%、8.8%和43.5%;侵袭抑制率分别为70.4%、6.9% 和63.5%.将wt或G129E转染细胞的黏附抑制率及侵袭抑制率与G129R转染细胞的比较,均有显著性差异(P＜0.05);但wt与 G129E转染细胞比较,均无显著性差异(P＞0.05 ).3种转染细胞总FAK水平虽无显著性差异(P＞0.05 ),但wt和G129E转染细胞其P397-FAK和 MMP-2水平都显著低于G129R转染细胞(P＜0.05).3种转染细胞间的E-Cd水平未见显著差异.RT-PCR分析显示,wt、G129E和G129R 3种转染细胞p53 mRNA水平无显著性差异,但均显著高于未转染细胞.结论 野生型PTEN基因所表达的蛋白具脂质和蛋白双特异磷酸酶活性,对乳腺癌细胞ZR-75-1的转移具有抑制作用,其机制与磷酸酶活性有关,其中蛋白磷酸酶活性可能起主要作用.     

野生型PTEN基因在乳腺癌细胞中对表阿霉素的增敏作用

目的探讨野生型PTEN基因在人乳腺癌细胞系MCF-7和ZR-75-1中对表阿霉素的增敏作用。方法腺病毒介导野生型PTEN基因导入人乳腺癌细胞系MCF-7和ZR-75-1,RT-PCR检测PTEN mRNA的表达,Western blot检测转染后PTEN蛋白的表达;Ad-PTEN感染联合不同浓度的表阿霉素处理细胞,采用CCK-8法测定细胞增殖抑制率和联合效应。结果腺病毒介导的PTEN基因导入法可明显地增加细胞中PTEN基因的表达,野生型PTEN 基因转染联合表阿霉素使乳腺癌细胞MCF-7对表阿霉素的敏感度增加了两倍,而使乳腺癌细胞ZR-75-1对表阿霉素的敏感度增加了十倍。结论腺病毒重组的野生型PTEN基因联合表阿霉素对人乳腺癌细胞增殖具有显著的协同抑制效应。     

野生型PTEN基因高表达对膀胱移行细胞癌EJ细胞的抑癌作用

目的 探讨外源性野生型人酪氨酸磷酸酶（PTEN）基因的高表达对膀胱移行细胞癌EJ细胞的抑癌作用。方法 利用携带人PTEN基因的野生型、磷酸酶域突变型质粒体外分别转染人膀胱移行细胞癌EJ细胞。Western blot检测目的基因PTEN的表达,观察细胞形态变化及超微结构变化;MTIO法检测细胞增殖率及转染细胞对吡柔比星（THP）和丝裂霉素（MMC）的敏感性;Western blot法检测bcl-2蛋白的表达。以空载质粒作为对照。结果 质粒转染后,EJ细胞的PTEN蛋白表达上升75．0％。转染野生型质粒后,EJ细胞异型性低,出现典型凋亡小体,细胞增殖率下降40．1％,bcl-2蛋白表达被下调,并提高了对THP和MMC的敏感性。而转染突变型质粒的EJ细胞则无此作用。结论 野生型PTEN基因在体外对膀胱移行细胞癌EJ细胞增殖有明显抑制作用,诱导细胞凋亡,磷酸酶域突变型PTEN基因无此作用。野生型PTEN的抑癌作用可能与其对bcl-2蛋白表达的下调有关。     

野生型PTEN基因对胶质细胞瘤侵袭力的影响

目的观察转入野生型PTEN基因的胶质瘤细胞体外侵袭力改变,探索PTEN基因对胶质瘤细胞影响方式.方法构建野生型PTEN基因的pcDNA3.1 Hygro(-)真核质粒载体,并用于转染PTEN基因失活的U251细胞系,采用重组基底膜侵袭模型,观察转染前后细胞侵袭力的改变.结果转染PTEN基因可以明显抑制U251细胞的侵袭力.结论 PTEN基因可通过抑制胶质瘤细胞的侵袭力达到抑制肿瘤生长.     

抑癌基因PTEN的表达对大肠癌细胞转移侵袭能力的影响

目的探讨抑癌基因PTEN的表达大肠癌细胞转移侵袭能力的影响.方法1.利用western blot法检测不同转移潜能的大肠癌细胞系内PTEN蛋白的表达水平,说明PTEN蛋白的表达对大肠癌细胞转移潜能的影响,2.用脂质体作载体,将PTEN基因转染大肠癌细胞株LOVO后,采用计数细胞悬液加到粘附底物后20 min和120 min的细胞贴壁数用以测定细胞粘附能力,采用Costar的浸润小室检测PTEN基因转染前后细胞的浸润能力.结果1.转移潜能高的LOVO细胞PTEN的表达量显著低于转移潜能较低的HT-29,LS-174T,2.未转染细胞(LOVO)、转染pcDNA3.0-PTEN的细胞(LOVO/pcD-NA3.0-PTEN)在特异性粘附底物(Laminin)上20 min时贴壁率分别为18.6%±1.4%和13.9%±0.48%(P＜0.05),120min时贴壁率分别为71.2%±2.5%和56.0%±1.6%(P＜0.05),3.采用Costar的浸润小室对LOVO、LOVO/pcDNA3.0-PTEN细胞的浸润能力分析结果显示细胞悬液静置培养6 h后,对照细胞LOVO浸润穿透多聚碳膜的细胞数为11.7±1.74个,LOVO/pcDNA3.0-PTEN细胞穿透多聚碳膜的细胞数为7.5±1.58个(P＜0.05).结论在肿瘤细胞内抑癌基因PTEN的表达与大肠癌的转移侵袭行为密切相关.     

PTEN基因转染对人膀胱癌细胞系BIU87增殖及侵袭活性的影响

背景与目的:PTEN(phosphataseandtensinhomologuedeletedfromchromosome10)是迄今为止发现的第一个具有磷酸酶活性的抑癌基因,在多种原发性恶性肿瘤和肿瘤细胞株中均存在有较高频率的缺失或突变,其失活与肿瘤的进程和预后相关。本实验研究外源性PTEN转染后,人膀胱癌细胞系BIU87增殖和侵袭活性的改变。方法:将携有PTEN基因的重组真核表达质粒pBp-PTEN转化大肠杆菌DH5α并扩增,抽提纯化质粒并进行酶切鉴定,pBp-PTEN体外转染BIU87细胞(pBp-PTEN-BIU87),筛选稳定转染的细胞并扩增培养,以转染了空质粒pBp的BIU87细胞(pBp-BIU87)和正常BIU87细胞为对照,用RT-PCR检测PTEN的表达情况,并用四甲基偶氮唑蓝比色法(MTT法)和细胞侵袭实验分别检测PTEN基因转染前、后BIU87细胞增殖和侵袭活性的变化。结果:pBp-PTEN的酶切鉴定证实含有目的基因PTEN;pBp-PTEN-BIU87细胞的RT-PCR产物经凝胶电泳有明显的阳性条带,而对照组则无;MTT发现,pBp-PTEN-BIU87细胞在第2、3和4天的吸光度(A值)明显低于两对照组(P<0.05),以正常BIU87细胞为对照,PTEN基因在第1、2、3、4天的细胞生长抑制率分别为4.27%、18.92%、19.54%、17.69%。细胞侵袭试验显示,各组细胞浸润穿透ECM膜的数目:pBp-PTEN-BIU8为39.3±7.7,BIU87和pBp-BIU87分别为48.1±13.2和48.9±11.0,pBp-PTEN-BIU87细胞明显少于两对照组(P<0.05)。结论:抑癌基因PTEN转染能降低膀胱癌细胞的增殖和侵袭活性。     

PTEN基因转染对白血病细胞VEGF调控作用的影响

目的:探讨在白血病细胞中与张力蛋白同源的10号染色体缺失的磷酸酶基因(phosphatase and tensin hemology deleted on chromosome ten gene,PTEN)对血管内皮生长因子(vascular endothelial growth factor,VEGF)及其受体1(VEGF receptor 1,VEGFR1)调控作用的影响.方法:将携带有野生型PTEN及绿色荧光蛋白(green fluorescent protein,GFP)基因的腺病毒(Ad-PTEN-GFP)及空载体腺病毒(Ad-GFP)转染人慢性粒细胞白血病急变细胞株K562,实时荧光定量PCR法检测不同转染组细胞中PTEN、VEGF和VEGF1 mRNA表达水平,Western印迹法检测PTEN、VEGF、Akt和磷酸化Akt蛋白的表达水平,并采用Transwell小室侵袭实验检测不同转染组细胞的侵袭性.通过MTT实验及FCM法检测PTEN基因对脐静脉内皮细胞株ECV304增殖和凋亡的影响.通过鸡胚尿囊膜(chick chorioallantoic membrane,CAM)体内血管生长实验检测PTEN基因对鸡胚血管生成的影响.结果:与空载体腺病毒(Ad-GFP)相比,Ad-PTEN-GFP 转染人白血病细胞K562后,VEGF及其受体的表达被明显抑制,并呈剂量依赖性负相关;同时,Ad-PTEN-GFP 转染后K562细胞侵袭能力明显减弱.PTEN基因转染能够抑制血管内皮细胞ECV304增殖,并促进其细胞凋亡,细胞周期阻滞在S期.PTEN基因转染可明显抑制CAM血管生长.结论:肿瘤抑制基因PTEN能够抑制内皮细胞增殖和白血病细胞侵袭,其作用机制可能是负调控白血病细胞VEGF表达以及抑制肿瘤血管新生.     

抑癌基因PTEN对肝癌细胞增殖的抑制及作用机制

目的探讨抑癌基因PTEN对肝癌细胞增殖和细胞周期的调控作用。方法构建野生型PTEN基因和突变型PTEN基因的真核表达载体pEGFP—WT—PTEN和pEGFP—PTEN;G129R。采用脂质体介导的基因转染法,分别将上述载体转染不表达PTEN蛋白的人肝细胞肝癌细胞系HHCC,经G418筛选,获得稳定表达PTEN蛋白的细胞克隆。以流式细胞仪测定细胞周期,以Western blot法分析稳定表达PTEN蛋白的肝癌细胞内源性的磷酸化AKT表达水平,同时与未进行基因转染和转染空载体pEGFP-C1的HHCC细胞进行对照。结果稳定表达野生型PTEN蛋白的肝癌细胞,细胞生长受到明显抑制,与转染空载体的HHCC细胞比较,G1期细胞比例显著增高,G2期和S期细胞比例显著降低,且差异有统计学意义（P〈0．05）;而转染突变型PTEN基因的HHCC细胞,与转染空载体的HHCC细胞比较,差异无统计学意义（P〉0.05）。与转染空载体的HHCC细胞比较,稳定表达野生型PTEN蛋白的HHCC细胞,其内源性磷酸化AKT水平明显减低;而转染突变型PTEN基因的HHCC细胞,其AKT水平无明显变化。结论野生型PTEN基因对肝癌细胞周期具有调控作用,而突变型PTEN基因丧失对肝癌细胞周期的调控作用;野生型PTEN基因可能通过降低AKT的活化而实现对肝癌细胞周期的调控。     

PTEN suppresses hyaluronic acid-induced matrix metalloproteinase-9 expression in U87MG glioblastoma cells through focal adhesion kinase dephosphorylation

Glioblastoma is a severe type of primary brain tumor and its invasion is strongly correlated with the secretion of matrix metalloproteinases (MMPs). To investigate a role of PTEN, a tumor suppressor gene, in the regulation of hyaluronic acid (HA)-induced invasion of glioma cells, we examined the secretion of MMP-9 in various glioma cells with or without a functional PTEN gene. The secretion of MMP-9 in glioma cells lacking functional PTEN (U87MG, U251MG, and U373MG) was induced by HA, although not in wildtype (wt)-PTEN-harboring cells (LN229, LN18, and LN428). In addition, stable expression of wt-PTEN into U87MG cells significantly decreased the secretion of HA-induced MMP-9 and basal levels of MMP-2, inhibiting the activation of focal adhesion kinase and extracellular signal-regulated kinase 1/2, whereas the secretion levels of the tissue inhibitor of metalloproteinase-1 and -2 were increased, finally resulting in the inhibition of invasion by HA in vitro. Ectopic expressions of adenoviral (Ad)-wt-PTEN and -lipid phosphatase-deficient (G129E)-PTEN, but not both protein and -lipid phosphatase-deficient (C124S)-PTEN, reduced MMP-9 secretion and invasion by HA. These results were also confirmed by expressions of Ad-wt-PTEN and Ad-G129E-PTEN in other glioblastoma cells lacking functional PTEN, U251MG, and U373MG. These findings strongly suggest the possibility that PTEN may block HA-induced MMP-9 secretion and invasion through its protein phosphatase activity.     

PTEN基因诱导人脑胶质瘤SHG-44细胞凋亡及bcl-2蛋白表达下调

目的　探讨PTEN基因对人脑胶质瘤SHG 44细胞凋亡及凋亡相关基因bcl 2表达的影响 ,阐明PTEN基因抑制肿瘤细胞增殖的机理。方法　PTEN基因体外转染SHG 44细胞 ,筛选阳性细胞克隆 ,以原位杂交、免疫组化方法检测PTEN基因的表达情况采用透射电镜、流式细胞仪和核DNA琼脂糖凝胶电泳检测细胞的凋亡情况以免疫荧光法检测bcl 2基因的表达。结果　PTEN基因转染的SHG 44细胞有PTEN基因和蛋白的表达。透射电镜下可见转染PTEN基因后细胞核染色质浓缩边集、胞浆浓缩、核碎裂及凋亡小体形成等典型的凋亡表现 ;流式细胞仪示细胞周期从G1 期到S期发生抑制 ,并且在G1 期峰前出现一明显的凋亡峰 (1 2 .9% ) ;细胞核DNA琼脂糖凝胶电泳呈现凋亡细胞特有的梯状条带 ;bcl 2的表达也显著下调。转染空载体和未转染的SHG 44细胞无明显的凋亡表现。结论　PTEN基因可诱导SHG 44细胞凋亡 ,并下调bcl 2蛋白的表达 ,这可能是PTEN基因抑制肿瘤细胞增殖的分子机制之一     

寡核苷酸阻断ROCK-1蛋白对人卵巢癌细胞恶性行为的影响

目的通过反义寡核苷酸(ASODN)对ROCK-1的特异性阻断,探讨ROCK-1蛋白在卵巢癌转移中的作用。方法将ROCK-1反义寡核苷酸(ASODN)以脂质体介导,转染人卵巢癌细胞系SW626和Caov-3细胞,采用逆转录聚合酶链反应(RT-PCR)与Western blot印迹法,检测转染前后ROCK-1蛋白的表达,Boyden小室观察ROCK-1 ASODN对SW626和Caov-3细胞侵袭及迁移能力的影响,采用二苯基溴化四氮唑蓝(MTT)比色法,测定转染前后细胞增殖及黏附能力的变化。结果转染ROCK-1 ASODN后,2株细胞内ROCK-1蛋白的表达明显减少,最大抑制率可达49.0%;细胞的侵袭能力受到明显抑制,10μmol/L组和20μmol/L组SW626细胞的侵袭能力分别为对照组的75.6%±3.8%和54.7%±2.9%,Caov-3细胞为68.8%±4.7%和50.0%±4.5%;转染2种浓度ASODN的SW626和Caov-3细胞的随机运动能力分别为对照组的80.0%±1.3%、63.7%±1.9%、72.0%±1.3%和55.9%±2.5%;定向运动能力分别为对照组的83.9%±1.4%、64.1%±1.3%、72.5%±3.4%和54.5%±1.9%。转染后2株细胞的体外黏附能力和增殖能力,均未显示出明显的变化。结论ROCK-1蛋白的表达与人卵巢癌细胞的体外侵袭和迁移密切相关,阻断ROCK-1的表达,可有效地抑制卵巢癌肿瘤细胞的转移。     

PTEN can inhibit in vitro organotypic and in vivo orthotopic invasion of human bladder cancer cells even in the absence of its lipid phosphatase activity

Recent studies have found a higher frequency of the PTEN tumor-suppressor gene alterations in invasive bladder carcinoma than in superficial disease, suggesting that PTEN is important in this process. A role of PTEN in bladder cancer invasion is further suggested by the fact that PTEN is a regulator of cell motility, a necessary component of tumor invasion. However, it is unknown whether PTEN is mechanistically involved in 'in vivo' tumor invasion or merely an epiphenomenon and, if the former is true, whether this process is dependent on its protein or lipid phosphatase activities. To address these issues, we stably transfected several commonly used human bladder cancer cell lines with known invasive phenotypes with either wild-type PTEN constructs or those deficient in the lipid phosphatase (G129E) or both protein and lipid phosphatase (G129R) activities. Here we show that chemotaxis was inhibited by both the wild-type and G129E mutant of PTEN but not by G129R-transfected cells. Using a novel organotypic in vitro invasion assay, we evaluated the impact of wild-type and mutant PTEN transgene expression on the invasive ability of T24T, a human bladder cancer cell line with a functionally impaired PTEN. Results indicate that the G129E mutant blocks invasion as efficiently as wild-type PTEN transfection. In contrast to the wild-type gene, this mutant has no effect on cell clonogenicity in agar. To further establish the role of PTEN in tumor invasion, we evaluated vector- and PTEN-transfected T24T cells in an orthotopic in vivo assay that faithfully reproduces human disease. Microscopic examination of murine bladders at the completion of this experiment parallels the results obtained with the organotypic assay. Our results are the first demonstration: (1) that the inhibitory effects of PTEN on cell motility translate into suppression of in vivo invasion; (2) that PTEN can inhibit tumor invasion even in the absence of its lipid phosphatase activity; (3) how organotypic in vitro approaches can be used as surrogates of in vivo invasion allowing rapid dissection of molecular processes leading to this phenotype while reducing the number of animals used in research.     

Protein phosphatase activity of PTEN inhibited the invasion of glioma cells with epidermal growth factor receptor mutation type III expression

PTEN is a major tumor suppressor gene that has been shown to inhibit cell invasion. Its mutation has been found in 20-40% of malignant gliomas. Meanwhile, the type III EGFR mutation (EGFRvIII), which was frequently found in gliomas, promoted cell invasion. In the present study, the effects of PTEN on cell invasion were investigated in U87DeltaEGFR glioblastoma cells with EGFRvIII expression but missing PTEN. The cell invasion was downregulated by transfection of phosphatase-active forms of PTEN (wild-type and G129E) but not by PTEN (C124A) with an inactive phosphatase domain; the effects were correlated with decreased tyrosine phosphatase levels of FAK at Tyr397, which was increased by EGFRvIII. Overexpression of FAK mutant (Y397F) could partially mimic the effect of PTEN on cell invasion. Although EGFRvIII increased the levels of P-Akt and PTEN eliminated it, PI-3K inhibitors, wortmannin or Ly294002, could not decrease the cell invasion. In conclusion, PTEN could inhibit cell invasion even in the presence of the constitutively active EGFR; this inhibition depended on its protein phosphatase activity, partially by dephosphorylating FAK, but not depended on its lipid phosphatase activity.     

A novel taspine derivative,HMQ1611, suppresses adhesion,migration and invasion of ZR-75-30 human breast cancer cells

Background

Taspine was screened for the first time from Radix et Rhizoma leonticis (Hong Mao Qi in Chinese) using cell membrane chromatography in our laboratory. Its anticancer and antiangiogenic properties were demonstrated, and it could serve as a lead compound in anticancer agent development. Here, we investigated the role of one of the derivatives, HMQ1611, with increased activity and solubility, on the regulation of breast cancer cell ZR-75-30 adhesion, migration and invasion.

Methods

The effect of HMQ1611 on adhesion, invasion and migration of human breast cancer cells ZR-75-30 was examined. The migration and invasive potential of ZR-75-30 cells were examined by wound-healing assays and matrigel invasion chamber assays. The adhesion to type IV collagen and laminin were evaluated by MTT assay. The expression and proteinase activity of two matrix metalloproteinases (MMPs), matrix metalloproteinases 2 (MMP-2) and matrix metalloproteinases 9 (MMP-9), were analyzed by Western blot analysis and gelatin zymography, respectively.

Results

HMQ1611 effectively inhibited ZR-75-30 cell invasion and significantly suppressed adhesion to type IV collagen and laminin-coated substrate in a dose-dependent manner. Western blot and gelatin zymography analysis showed that HMQ1611 significantly inhibited the expression and secretion of MMP-2 and MMP-9 in ZR-75-30 cells. Additionally, treatment of ZR-75-30 cells with HMQ1611 downregulated the expression of MMP-2 and MMP-9.

Conclusions

HMQ1611 had potential to suppress the adhesion, migration and invasion of ZR-75-30 cancer cells, and it could serve as a potential novel therapeutic candidate for the treatment of metastatic breast cancer.     

Reversal of the malignant phenotype of ovarian cancer A2780 cells through transfection with wild-type PTEN gene

Objective

PTEN (phosphatase and tensin homologue deleted on chromosome 10) is a tumor suppressor gene identified on human chromosome 10q23. Substantial studies have demonstrated that PTEN can inhibit cell proliferation, migration and invasion of many cancer cells. The purpose of this study was to determine whether upregulation of PTEN gene by transfection wild-type PTEN gene to ovarian cancer cells can inhibit growth and migration and to explore the potential for PTEN gene therapy of ovarian cancers.

Method

Wild-type and phosphatase-inactive (C124A) PTEN plasmids were transfected into ovarian epithelial cancer A2780 cells, and their effects on cell apoptosis, cell proliferation, cell migration and cell invasion were analyzed by flow cytometry analysis, TUNEL assay, MTT assay, wound-healing assay and transwell assay.

Results

Both wild-type and mutant PTEN can upregulate the expression of PTEN gene dramatically; however, it is wild-type PTEN not phosphatase-inactive PTEN that can induce apoptosis and decrease cell migration, invasion and proliferation in ovarian cancer cells.

Conclusion

These results demonstrated that PTEN had played an important role in the cell proliferation, cell migration and invasion dependent on its phosphatase activity. Enhanced expression of PTEN by gene transfer is sufficient to reverse the malignant phenotype of ovarian cancer cells and transfection of ovarian cancer cells with wild-type PTEN gene might be another novel approach for therapeutic intervention in ovarian cancer.