siRNA 抑制Sema4C 基因表达对人乳腺癌细胞恶性行为的影响*

目的:研究小干扰RNA（small interf ering RNA,siRNA ）抑制轴突导向蛋白分子（Semaphorin 4C,Sema4C）基因的表达对人乳腺癌细胞MDA-MB-231 体外迁移、侵袭及增殖的影响,并初步探讨其作用机制。方法:根据Sema4C 基因设计序列特异性的siRNA（Sema4C-siRNA ）,在脂质体介导下转染MDA-MB-231 细胞,Western blot方法检测基因封闭效应,利用细胞划痕实验、Tran ?swell小室侵袭实验及CFSE流式细胞仪方法检测细胞转染前后迁移、侵袭及增殖能力的变化,Western blot检测磷酸化AKT（p-AKT ）在转染前后细胞中表达的变化。结果:转染Sema4C-siRNA 72小时后,乳腺癌MDA-MB-231 细胞株（MDA-MB-231/Si）Sema4C 蛋白表达明显下降,与未转染细胞MDA-MB-231 相比,MDA-MB-231/Si细胞体外迁移能力减弱,侵袭及增殖能力明显下降;p-AKT 表达水平在MDA-MB-231/Si细胞中明显降低。结论:Sema4C-SiRNA 转染人乳腺癌MDA-MB-231 细胞可下调细胞中Sema4C 蛋白表达水平,Sema4C-SiRNA 对MDA-MB-231 细胞的体外迁移、侵袭和增殖有抑制作用,这可能与p-AKT 的下调有关。      

动力相关蛋白-1(MRP-1/CD9)对卵巢癌细胞体外增殖和运动的影响

目的：动力相关蛋白-1（MRP-1／CD9）是四跨膜蛋白超家庭（transmetubrane 4,stperfanily,TM4SF）成员之一,参与调控细胞的生长,分化,细胞间粘附和迁移,本实验旨在研究MRP-1 CD9对人卵巢癌SKON-3细胞株体外增殖和运动能力的影响并探讨其与PI4K/AKT信号通路的相关性,方法：应用RT-PCR获得CD9全长cDNA片段,正向插入pcDNA3.1表达载体,将重组质粒导入SKOV-3细胞中,应用RT-PCR efse一流式细胞测定和单层伤口愈合实验等方法观察梁前后SKOV-3细胞PI4K和AKTmRNA表达水平,细胞增殖及其运动能力变化,结果：成功构建正义全长CD9真核表达载体,获得稳定表达CD9的SKOV-3克隆株,与穿空质粒转染和不转染的SKON-3细胞相比,SKON-3/CD9细胞PI4KmRNA的表达明显被抑制,抵制率为40%;AKTmRNA的表达水平上调3.13倍,细胞增殖和运动能力均有明显升高.结论：CD9促进人卵巢癌SKOV-3细胞的体外增殖 和运动能力,可能是通过PI4K/AKT信号通路发挥作用的,对卵巢癌恶性进展发挥重要作用.     

脾源性酪氨酸激酶抗肿瘤侵袭迁移的作用机制

目的：研究脾源性酪氨酸激酶（spleen tyrosine kinase,Syk）抗人乳腺癌肿瘤细胞的侵袭迁移能力,并对其作用机制进行初步探讨。方法：将全长SykcDNA经脂质体介导转染Syk表达阴性的高侵袭性人乳腺癌细胞MDA-MB-231,Transwell小室法检测转染前后肿瘤细胞侵袭迁移能力的变化,流式细胞术及酶联免疫吸附测定法检测与侵袭转移相关的血管内皮生长因子和基质金属蛋白酶-9的表达情况。结果：转染Syk全长基因的MDA-MB-231细胞与转染空载体及未转染的MDA-MB-231细胞相比,侵袭及迁移实验中的穿膜细胞数（总迁移细胞数/5个高倍视野）均明显减少（P〈0.05）;血管内皮生长因子及基质金属蛋白酶-9的表达量亦明显减少（P〈0.05）。结论：转染SykcDNA可通过降低转染肿瘤细胞血管内皮生长因子及基质金属蛋白酶-9的表达,参与其抗肿瘤侵袭迁移作用。     

沉默CD44表达对乳腺癌细胞MDA-MB-231增殖与侵袭的影响

目的:探索乳腺癌细胞MDA-MB-231及MCF-7中CD44分子的表达水平差异及沉默CD44对乳腺癌细胞MDA-MB-231增殖、侵袭和迁移的影响。方法:利用qRT-PCR及Western blot技术检测细胞中CD44基因表达水平;设计并合成CD44的siRNA片段(CD44-siRNA)转染乳腺癌细胞,利用qRT-PCR、Western blot技术检测细胞中CD44基因表达水平的变化;MTT检测MDA-MB-231细胞增殖;Transwell侵袭实验检测MDA-MB-231细胞的迁移与侵袭能力变化。结果:CD44在侵袭性乳腺癌细胞MDA-MB-231中的表达高于非侵袭性乳腺癌细胞MCF-7,CD44-siRNA下调了 MDA-MB-231细胞中CD44 mRNA与蛋白水平的表达,并抑制了细胞的增殖和侵袭转移能力。结论:CD44-siRNA能够下调CD44的表达,并有效抑制乳腺癌细胞MDA-MB-231的增殖及其侵袭迁移力。     

小RNA干扰降低COX-2表达对乳腺癌细胞趋化和侵袭能力的影响

目的探讨利用小RNA干扰技术降低COX-2表达对高度恶性乳腺癌MDA-MB-231细胞趋化和侵袭能力的影响。方法应用合成的小RNA干扰质粒转染MDA-MB-231细胞株,采用反转录－聚合酶链反应(RT-PCR)检测COX-2 mRNA的表达。通过趋化运动实验检测细胞的运动能力;体外侵袭实验检测细胞的侵袭能力。结果限制性内切酶的酶切结果和DNA测序结果显示成功构建了干扰质粒pSUPER-siCOX-2,转染后的细胞株分别命名为MDA-MB-231/pSUPER-basic（对照组）和MDA-MB-231/pSUPER-siCOX-2（实验组）。转染后48 h,与MDA-MB-231/pSUPER-basic细胞相比,MDA-MB-231/pSUPER-siCOX-2细胞的COX-2 mRNA表达水平下降(P<0.01);COX-2减低的乳腺癌细胞的趋化运动能力比对照组细胞降低(P<0.01);COX-2减低的乳腺癌细胞侵袭并穿透Matrivgel膜基质的细胞数量比对照组细胞少(P<0.01)。结论利用siRNA干扰技术降低COX-2表达对乳腺癌MDA-MB-231细胞株的趋化和侵袭能力具有明显的抑制作用。     

趋化因子CCL28过表达对人乳腺癌细胞增殖的影响

背景与目的:CCL28,又称为黏膜相关上皮趋化因子(mucosa-associated epitheliachemokine,MEC),是趋化因子CC家族中的一员。研究表明,CCL28与肿瘤发生、发展有关,但对其在乳腺癌中的功能还知之甚少。本文旨在探讨CCL28过表达在体外对乳腺癌细胞MDA-MB-231增殖的影响。方法:构建CCL28过表达载体pBabe-CCL28表达质粒,将重组的pBabe-CCL28基因和空载体pBabe转染细胞Phoenix,利用逆转录病毒感染乳腺癌细胞MDA-MB-231,通过嘌呤霉素药物筛选获得稳定表达CCL28的MDA-MB-231/CCL28细胞系和感染空载体的MDA-MB-231/vector细胞系,利用半定量RT-PCR、实时荧光定量PCR及蛋白质印迹法(Western blot)检测CCL28的基因表达和蛋白质水平;利用CCK8、软琼脂克隆培养及流式细胞术检测CCL28过表达后细胞增殖、克隆形成能力及凋亡的变化;利用Western blot检测CCL28过表达后凋亡相关蛋白的变化。结果:成功建立了稳定表达CCL28的细胞系MDA-MB-231/CCL28,与空载体对照组相比,pBabe-CCL28质粒感染入细胞后CCL28基因表达水平明显增高,说明CCL28 cDNA重组质粒构建成功。CCK8及软琼脂克隆实验结果显示,MDA-MB-231/CCL28的增殖能力明显高于MDA-MB-231/vector,差异有统计学意义(P<0.05)。流式细胞术结果显示,MDA-MB-231/CCL28细胞凋亡比例减少,差异有统计学意义(P<0.05)。Western blot结果显示,抗凋亡蛋白Bcl-2的表达增加。结论:CCL28过表达可以显著促进人乳腺癌细胞MDA-MB-231的增殖能力,抑制乳腺癌细胞凋亡,后者可能与Bcl-2上调有关。CCL28有望成为临床治疗乳腺癌的潜在基因靶点。     

NRP-1过表达对乳腺癌细胞MDA-MB-231、SK-BR-3生物学行为的影响

目的 通过上调乳腺癌细胞MDA-MB-231、SK-BR-3中NRP-1的表达,观察NRP-1对细胞增殖、凋亡、迁移及侵袭能力的影响。方法 构建pcDNA3.1-NRP-1表达载体,脂质体介导NRP-1 表达质粒转染MDA-MB-231、SK-BR-3细胞,用G418筛选出稳定转染的乳腺癌细胞株。利用RTqPCR、Western blot法分别检测NRP-1基因mRNA及其蛋白表达;CCK-8法、AnnexinⅤ-APC/7-AAD法、Transwell小室分别检测转染细胞增殖率、凋亡率及侵袭、迁移能力。结果 成功构建pcDNA3.1- NRP-1表达载体,转染MDA-MB-231、SK-BR-3细胞并筛选稳定表达系。与对照组相比,过表达组细胞的NRP-1 mRNA及蛋白表达水平明显升高（均P<0.05）;NRP-1过表达组的细胞较对照组增殖率增加、凋亡率降低、侵袭及迁移能力增强（均P<0.05)。结论 NRP-1在乳腺癌发展、浸润、转移中起着一定的作用,它可促进乳腺癌细胞增殖、迁移和侵袭,抑制其凋亡。     

结缔组织生长因子转染对人乳腺癌细胞系生物学行为的影响

背景与目的:结缔组织生长因子(CTGF)是CCN家族成员之一,参与体内多种生理和病理生理过程。本研究探讨CTGF对人乳腺癌细胞生物学行为的影响。方法:构建含有CTGF开放读码框的真核表达质粒,通过脂质体介导的方法将正义质粒转染MCF-7细胞,反义质粒转染MDA-MB-231细胞。观察CTGF不同表达水平与乳腺癌细胞增殖、凋亡、周期分布和体外侵袭等生物学行为的关系。结果:转染正义质粒使MCF-7细胞CTGF表达上调,抑制细胞增殖,促进细胞凋亡,细胞发生G0G1期阻滞,体外侵袭能力下降。转染反义质粒使MDA-MB-231细胞CTGF表达下调,促进细胞增殖,减少细胞凋亡,增强细胞体外侵袭能力,但对细胞周期无影响。结论:CTGF具有抑制乳腺癌细胞生长和侵袭的功能。促进细胞凋亡是CTGF抑制乳腺癌细胞体外生长的机制之一。CTGF可能对细胞周期有一定的影响。     

Cathepsin B反义RNA抑制乳腺癌细胞的侵袭和迁移

摘 要　目的：探讨人cathepsin B(CatB)反义RNA在乳腺癌细胞侵袭与迁移中的作用。方法: 构建携CatB反义RNA的重组质粒pBudCE4.1-antiCatB,采用脂质体法将重组质粒瞬时转染人乳腺癌细胞MDA-MB-231。Western blotting法检测MDA-MB-231细胞中CatB蛋白的表达, MTT法检测MDA-MB-231细胞的增殖,细胞-基质黏附实验检测反义CatB对MDA-MB-231细胞黏附能力的影响,体外侵袭、迁移实验分析反义CatB表达对MDA-MB-231细胞体外侵袭和迁移能力的影响。结果:成功构建pBudCE4.1-antiCatB表达载体。转染MDA-MB-231细胞后,与未转染组细胞和转染空载体组细胞相比,转染组MDA-MB-231细胞的CatB蛋白表达水平明显降低[(0.96±0.02) vs(1.98±0.23),(1.84±0.08),P<0.05];转染组细胞的增殖受到明显抑制[(0.255±0.017) vs(0.458±0.033),(0.421±0.022),P<0.01];转染组细胞的黏附（基质胶或纤维黏连蛋白）能力明显下降[(0.054±0.017) vs(0.111±0.018),(0.107±0.017), P<0.01;或(0.052±0.008) vs(0.120±0.014),(0.113±0.009), P<0.01];转染组细胞的侵袭和迁移能力也明显降低[(52.80±7.76) vs(124.00±44.54),(116.80±32.87), P<0.01;(60.25±8.73) vs(132.50±12.15),(119.20±25.13), P<0.01]。结论:CatB反义RNA可抑制乳腺癌细胞体外生长、黏附、迁移和侵袭能力。     

TAGLN基因过表达对乳腺癌细胞迁移和侵袭能力的影响

目的 研究TAGLN基因过表达对人乳腺癌细胞MDA-MB-231迁移能力和侵袭能力的影响及其分子机制.方法 对MDA-MB-231细胞采用慢病毒表达系统构建TAGLN基因稳定过表达细胞株,将MDA-MB-231细胞正常培养设为空白对照组,空载体慢病毒包装感染MDA-MB-231细胞后获得的稳定转染细胞株设为空载体对照组.Real time PCR和Western blot检测TAGLN mRNA和蛋白表达,划痕实验和Transwell侵袭实验检测细胞迁移和侵袭能力,Western blot检测TAGLN基因过表达后基质金属蛋白酶2(matrix metalloproteinase-2,MMP-2)和MMP-9蛋白表达变化.结果 MDA-MB-231细胞感染TAGLN基因过表达慢病毒载体后,细胞中TAGLN mRNA表达和蛋白表达升高(均P＜0.01),成功构建TAGLN基因过表达稳定细胞株(231-TAGLN).231-TAGLN细胞的体外迁移能力和侵袭能力下降,与空载体对照组和空白对照组细胞比较,差异均具有统计学意义(均P＜0.01),同时伴有MMP-2和MMP-9表达水平降低(均P＜0.01).结论 TAGLN基因过表达可以抑制乳腺癌细胞的迁移和侵袭,MMP-2和MMP-9基因表达下降可能参与这一过程.     

KAI1基因对乳腺癌细胞体外增殖的抑制作用

目的研究KAI1基因对乳腺癌细胞体外增殖的抑制作用。方法应用脂质体法将pCMV-KAI1质粒转染人高转移性人乳腺癌细胞株MDA-MB-231中,免疫印迹方法检测蛋白表达;利用四甲基偶氮唑盐(MTT)法、平板克隆形成实验、体外黏附及侵袭力实验判断细胞增殖能力及黏附、侵袭力的变化。流式细胞术检测细胞生长周期的变化。结果获得了稳定表达KAI1基因的MDA- MB-231乳腺癌细胞克隆。MTT法显示,转染KAI1基因组的集落形成率(25.33%±2.36%)较转染前(43.17%±2.75%)明显降低(P<0.05)。体外黏附及侵袭力实验表明,转染组的细胞黏附侵袭能力低于未转染组和转染空载体组(P<0.05)。流式细胞术显示,转染KAI1后,G_0/G_1期细胞数量增高,从36.78%±0.61%升高至64.00%±7.56%;G_2/M期数量降低,由17.88%±0.76%降至7.63%±0.60%,差异有统计学意义。结论KAI1基因可以抑制乳腺癌细胞的增殖黏附和侵袭能力,并可能通过调节细胞周期来影响细胞的增殖。     

Gab2通过GSK-3β/Snail信号通路促进乳腺癌的上皮-间质转化

背景与目的：越来越多的证据显示,Grb2协同结合蛋白2(Grb2 binding protein-2,Gab2)与肿瘤的侵袭转移相关,但Gab2与乳腺癌上皮-间质转化(epithelial-mesenchymal transition,EMT)的关系尚不清楚。本研究旨在探讨Gab2对乳腺癌EMT标志物的影响,明确Gab2在乳腺癌侵袭和转移中的作用机制。方法：采用免疫组织化学染色法检测80例乳腺癌组织中Gab2及EMT标记物上皮性钙黏着蛋白(E-cadherin)、波形蛋白(vimentin)的表达情况并分析其相关性,用蛋白[质]印迹法(Western blot)检测乳腺组织Gab2的表达情况,采用小干扰RNA(siRNA)技术降低乳腺癌细胞系MDA-MB-231中Gab2的表达,采用划痕实验检测表皮生长因子(epithelial growth factor,EGF)刺激后转染细胞的侵袭能力变化,用Western blot检测敲低Gab2后MDA-MB-231细胞中E-cadherin及vimentin的表达情况,同时检测p-GSK-3β的表达情况、转录因子Snail转核情况。结果：Gab2在乳腺癌组织中的表达与E-cadherin的表达呈负相关,而与vimentin的表达呈正相关(P<0.05);乳腺癌组织中Gab2的表达量明显高于正常乳腺组织;siRNA质粒转染后,SiGab2/MDA-MB-231细胞组中Gab2蛋白的表达量明显降低,结果显示转染成功,划痕实验显示细胞的侵袭能力减弱,表明Gab2影响乳腺癌细胞系的侵袭能力;敲低Gab2后,MDA-MB-231细胞中的E-cadherin的表达明显升高,而vimentin的表达明显降低;GSK-3β的磷酸化受到抑制,而Snail在敲低Gab2的细胞核中的表达明显下调。结论：Gab2可以通过GSK-3β/Snail信号通路促进乳腺癌的EMT,从而促进乳腺癌的侵袭和转移。     

The effects of RKIP gene expression on the biological characteristics of human triple-negative breast cancer cells in vitro

The purpose of this study was to investigate the effect of Raf kinase inhibitor protein (RKIP) on the growth, proliferation, invasion and metastasis of triple-negative breast cancer (TNBC) cells to provide experimental evidence for developing future therapies against human TNBC. The pcDNA3.1-RKIP eukaryotic expression vector was constructed and transfected into the TNBC cell line MDA-MB-231. The alterations of the biological characteristics of RKIP-transfected MDA-MB-231 cells were analyzed using the following approaches: a growth curve, a 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide (MTT) assay, bromodeoxyuridine (BrdU) staining and a cell migration assay. The effects of the RKIP gene on MMP-1 and MMP-2 expression were also examined. The pcDNA3.1 empty vector-transfected and mock-transfected MDA-MB-231 cells were used as control groups. Compared with the empty vector-transfected and mock-transfected cells, the cell growth of RKIP-transfected MDA-MB-231 cells was significantly reduced. The empty vector-transfected group was not significantly different compared with the mock-transfected MDA-MB-231 cells. The results of the MTT and BrdU assays demonstrated that the proliferation of pcDNA3.1-RKIP-transfected cells was significantly reduced compared to the control cells (P < 0.05). The result of the cell migration assay suggested that the cross-membrane migration rate of the pcDNA3.1-RKIP-transfected cells was significantly lower than that of the control MDA-MB-231 cells (P < 0.05). We also demonstrated that RKIP may inhibit MMP-1 and MMP-2 expression in MDA-MB-231 cells. The RKIP gene may play a role in inhibiting cellular proliferation. The RKIP gene may also have some inhibitory effects on the invasiveness and metastatic capability of human TNBC cells.     

miR-4728-3p通过PI3K/AKT信号通路调控DOT1L基因抑制乳腺癌细胞增殖、侵袭和迁移

目的:探讨miR-4728-3p通过调控类端粒沉默干扰体-1(disruptor of telomeric silencing 1-like,DOT1L)基因对乳腺癌细胞增殖、侵袭和迁移的影响。方法:使用乳腺癌细胞MCF-7、MDA-MB-231及人正常乳腺细胞MCF-10A。转染MCF-7和MDA-MB-231细胞随机分为NC组(转染miR-4728-3p-NC)和敲低组(转染miR-4728-3p-inhibitor)。利用RT-qPCR技术检测不同的细胞中miR-4728-3p和DOT1L的表达量改变情况。集落克隆形成实验和EDU实验可以同时检测体内各个细胞异常增殖的情况;TUNEL荧光标记检测法和流式细胞术实验可以同时检测不同组癌细胞的凋亡变化;划痕实验和Transwell实验可以同时检测到在各个细胞内因不同处理而可能产生的细胞迁移率和侵袭力的改变;Western blot检测与细胞凋亡状态相关细胞蛋白以及与细胞通路凋亡相关细胞蛋白p-AKT和p-PI3K相对表达的含量。结果:在乳腺癌细胞MCF-7、MDA-MB-231以及SKBR3中发现miR-4728-3p和DOT1L的表达高于人正常乳腺细胞MCF-10A(P＜0.05)。转染细胞miR-4728-3p后,与NC组细胞进行实验比较,发现敲低组细胞中miR-4728-3p和DOT1L的表达量明显降低,且敲低组细胞的增殖能力明显减弱,细胞凋亡率明显升高,细胞迁移能力大大降低。敲低组的细胞凋亡活性蛋白相对表达明显发生变化。其中p-AKT与p-PI3K蛋白均被抑制激活。RT-qPCR和Western blot实验验证DOT1L是miR-4728-3p的下游靶向基因。结论:敲低miR-4728-3p可以下调DOT1L的表达从而促进乳腺癌细胞凋亡,抑制乳腺癌细胞增殖,同时使乳腺癌细胞侵袭和迁移能力减弱。     

Histone deacetylases 1, 6 and 8 are critical for invasion in breast cancer

Histone deacetylases (HDACs) are associated with the development and progression of cancer, but it is not known which of the HDAC isoforms play important roles in breast cancer metastasis. This study identified the specific HDAC isoforms that are necessary for invasion and/or migration in human breast cancer cell lines. MDA-MB-231 cells were significantly more invasive and expressed higher levels of matrix metalloproteinase-9 (MMP-9) compared to MCF-7 cells. We compared the expression of HDAC isoforms between MCF-7 and MDA-MB-231 cells and found greater expression of HDAC4, 6 and 8 in MDA-MB-231 cells by RT-PCR and Western blot analyses. In addition, apicidin, a histone deacetylase inhibitor, was shown to attenuate the invasion, migration and MMP-9 expression in MDA-MB-231 cells. Using specific siRNAs directed against HDAC1, 4, 6 and 8, we show that inhibition of HDAC1, 6 and 8, but not HDAC4, are responsible for invasion and MMP-9 expression in MDA-MB-231 cells. We analyzed the invasiveness of MCF-7 cells overexpressing HDAC1, 4, 6 or 8 and found that overexpression of HDAC1, 6 or 8 increased invasion and MMP-9 expression. By developing HDAC isoforms as potential biomarkers for breast cancer metastasis, the present study can be extended to developing therapies for breast cancer invasion.     

Suppression of pulmonary metastasis using adenovirally motility related protein-1 (MRP-1/CD9) gene delivery

Previously we showed that MRP-1/CD9 might prevent tumor metastasis by suppression of cell motility and invasion of tissue barriers. The present study explored the possibility of preventing metastasis of mouse melanoma BL6 by expression of MRP-1/CD9 through gene transfer. A replication-deficient adenovirus vector was used for the in vivo transfer of MRP-1/CD9 cDNA. Intratumor injection of an adenovirus vector (rAd-MRP-1/CD9) expressing MRP-1/CD9 resulted in a 73.7% reduction in the number of pulmonary metastases of mice and the median survival time of mice treated with rAd-MRP-1/CD9 was significantly longer than those treated with the rAd-beta-gal vector (103.2 approximately plus;8.5 days vs 71.2 approximately plus;5.2 days, P<0.001 respectively). These results support the expression of MRP-1/CD9 through gene transfer as a therapeutic strategy for preventing metastases and prolonging survival, and support the feasibility of gene transfer in a clinically relevant setting.     

Identification of the functional role of AF1Q in the progression of breast cancer

A novel highly metastatic MDA-MB-231HM cells, derived from MDA-MB-231, was established in our institute. RT-PCR, real-time PCR and Western blot showed that AF1Q gene was differentially expressed between highly metastatic MDA-MB-231HM cells and its parental MDA-MB-231 cells. However, its molecular mechanisms in breast cancer metastasis remain to be characterized. To investigate the effects of AF1Q on the progression of human breast cancer cells, in the present study, recombinant expression plasmid vectors of the human AF1Q gene was transfected into MDA-MB-231 cells. We demonstrated that AF1Q overexpression enhanced the in vitro proliferation and invasive potential of breast cancer cells. Focused microarray analyses showed that 22 genes were differentially expressed between AF1Q transfected cells and its parental counterparts. Integrin alpha3, accompanied by up-regulation of Ets-1 and MMP-2, significantly enhanced the in vitro invasive potential of human breast cancer cells mediated by AF1Q. Estrogen-responsive ring finger protein gene (EFP), also played a role in the enhancement of in vitro proliferation of human breast cancer cells mediated by AF1Q, accompanied by down-regulation of 14-3-3delta. The association was ERalpha independent. These results were further demonstrated by RNA interference (RNAi) experiment in vitro. In in vivo study, we also demonstrated that AF1Q transfected breast cancer cells grew much faster and had more pulmonary metastases than vector-transfected or its parental counterparts. On the contrary, AF1Q knockdown cells grew slower and had less pulmonary metastasis. Similar effects of AF1Q on integrin alpha3, Ets-1, MMP-2, EFP, and 14-3-3delta expression observed in vitro studies were also found in the in vivo study. Taken together, these results provide functional evidences that overexpression of AF1Q leads to a more progression in human breast cancer, at least in part, through regulating the integrin alpha3, Ets-1, MMP-2, EFP, and 14-3-3delta expression.