GALNT14对人乳腺癌MCF-7细胞迁移的影响

构建真核表达载体pcDNA 3.1-Flag-T14,重组质粒经酶切分析及测序鉴定后,利用脂质体将重组质粒转染人乳腺癌细胞系MCF-7细胞,经G418筛选并建立稳定转染GALNT14细胞株.应用半定量RT-PCR、Western blot检测稳定细胞株GALNT14 mRNA及蛋白表达水平,细胞划痕修复及穿膜试验检测GALNT14基因对MCF-7迁移能力的影响,同时RT-PCR检测GALNT14对MMP-2,MMP-9,TGF-β1及VEGF等肿瘤浸润转移相关因子表达的影响.结果显示成功构建了真核重组表达载体pcDNA 3.1-Flag-T14,经RT-PCR和Western blot检测显示成功获得了稳定表达GALNT14的MCF-7细胞株;GALNT14能够提高MCF-7细胞株的迁移能力,且能增加侵袭转移相关因子MMP-2,MMP-9,TGF-β1及VEGF的表达.结论:GALNT14可明显促进MCF-7细胞的迁移,可能在肿瘤侵袭转移中起重要作用.     

新的蒽醌类衍生物1-硝基-2-酰基蒽醌-苯丙氨酸通过抑制NF-κB/p65信号通路降低乳腺癌MCF-7细胞的迁移能力北大核心CSCD

肿瘤细胞的侵袭和转移与大多数癌症患者的死亡率密切相关。了解肿瘤细胞的迁移机制可为阻断肿瘤细胞的转移提供一个关键的策略。蒽醌衍生物具有一定的抗肿瘤作用,我们结合抗肿瘤药物的作用机制以及蒽醌类衍生物的构效关系,设计合成了一类新的酰胺蒽醌衍生物1-硝基-2-酰基蒽醌-苯丙氨酸(简称C7),发现其具有很好的抗肿瘤活性。为了探究蒽醌类衍生物C7对人乳腺癌MCF-7细胞迁移的作用及其机制,本文首先采用MTT比色法检测蒽醌类衍生物C7对人乳腺癌细胞MCF-7生长活力的影响,结果证明较高浓度(60~100μg/m L)的蒽醌类衍生物C7对乳腺癌MCF-7细胞的增殖具有明显的抑制作用。其次,采用细胞划痕实验检测C7对MCF-7细胞迁移的影响,发现较低浓度(20~40μg/m L)的蒽醌类衍生物C7可以显著降低MCF-7细胞的迁移率。为进一步探究C7抑制MCF-7细胞迁移的分子机制,通过免疫荧光技术检测NF-κB/p65蛋白的核转位情况;同时利用qRT-PCR及Western印迹实验检测C7对MCF-7细胞中NF-κB/p65通路及迁移相关基因和蛋白质表达的影响。结果表明C7可以下调细胞质中IκBα的磷酸化,降低NF-κB/p65蛋白的核转位,减小MMP-2和MMP-9蛋白的表达。因此,C7可能是通过抑制NF-κB/p65信号通路的活化,抑制MMP-2和MMP-9蛋白的表达,进而抑制MCF-7细胞的迁移。     

miR-125a-5p通过靶向调控GAB2抑制乳腺癌细胞的迁移能力

miR-125a-5p可负性调节GAB2表达,抑制胶质瘤细胞的侵袭和转移。本研究旨在证明miR-125a-5p抑癌作用的普遍性,即miR-125a-5p是否可通过靶向抑制GAB2抑制乳腺癌细胞的迁移。荧光素酶实验结果显示,miR-125a-5p可特异识别GAB2的3′-UTR,抑制报告酶的表达。荧光定量PCR结果揭示,与正常乳腺上皮细胞MCF-10A比较,miR-125a-5p在乳腺癌细胞MDA231和MCF-7中的表达明显降低;与迁移能力相对较低的MCF-7细胞比较,miR-125a-5p在迁移能力较高的MDA231细胞中的表达量更低。Western 印迹结果证明,与空载体（对照）和anti-miR125a 5p转染细胞比较,转染miR-125a-5p明显抑制GAB2蛋白在乳腺癌细胞中的表达。Transwell结果显示,与空载体转染的对照细胞比较,转染miR-125a-5p的乳腺癌细胞穿过基质胶的细胞数明显减少;相反,转染anti-miR125a-5p的细胞穿过基质胶的细胞数却明显增多。上述结果提示,miR-125a-5p在正常的乳腺细胞中高表达,而在乳腺癌细胞中低表达,其表达水平与癌细胞的迁移能力和GAB2表达呈反向关系。本研究结果还提示,miR-125a-5p通过靶向负调控GAB2抑制乳腺癌细胞的迁移能力。总之,本研究证明,miR-125a-5p在肿瘤中发挥抑癌作用。     

SB-431542抑制乳腺癌细胞BT-549的增殖和侵袭及其机理研究

肿瘤转移是导致肿瘤患者死亡的最主要原因,TGF-β超家族成员Nodal分子被证实参与肿瘤细胞的增殖和转移,因而基于Nodal信号为靶标开展抗肿瘤研究成为可能。该研究应用Western blot检测乳腺癌细胞株BT-549、T-47D、MCF-7、SK-BR-3和MDA—MB-231中的Nodal和基质金属蛋白酶-2（matrix metalloproteinase-2,MMP-2）的表达水平,发现它们在BT-549细胞中表达量最高。然后采用不同浓度_Nodal信号抑制剂SB．431542（1-50μmol／L）处理BT-549细胞48h,利用MTT法揭示20～50gmol／L的SB-431542抑制该细胞增殖。进一步利用细胞划痕和Transwell实验证明,10μmol／L的SB-431542可抑制乳腺癌细胞的迁移和侵袭。最后,通过明胶酶谱和Westernblot显示,10～30gmol／L的sB．431542可剂量依赖性地抑制MMP-2的表达和活性。上述结果说明,SB-431542通过阻断Nodal信号通路可效抑制乳腺癌细胞BT-549的增殖、迁移和侵袭,其作用机制可能与降低MMP-2的表达和活性有关。     

整合素β2促进人乳腺癌细胞MCF-7的迁移,侵袭与粘附

本研究主要目标为探讨整合素β2 (ITGB2)的高表达对人乳腺癌细胞MCF-7迁移,侵袭与粘附能力的影响。本研究首先构建了ITGB2过表达质粒,实验设阴性对照组(pcDNA-3.1+)与ITGB2基因过表达组(pcDNA-3.1+/ITGB2)。ITGB2过表达质粒转染MCF-7细胞后,采用逆转录PCR与Western blotting方法分别检测ITGB2 mRNA转录水平与蛋白翻译水平;流式细胞术检测细胞周期的改变;划痕实验检测细胞横向迁移能力;Transwell小室实验检测细胞纵向迁移能力及侵袭能力;人脐静脉血管内皮细胞(HUVEC)粘附实验检测癌症细胞与血管内皮细胞之间的粘附能力,Western blotting实验检测侵袭相关指标MMP9,整合素经典通路中FAK蛋白磷酸化水平的改变。研究结果表明:转染ITGB2过表达质粒后,MCF-7细胞中ITGB2的m RNA水平(p<0.01)与蛋白水平(p<0.05)均显著增高;流式细胞术实验中,实验组S期的细胞所占比例与对照组无明显差异;划痕实验与Transwell小室实验中,实验组的迁移侵袭能力显著性增强;人脐静脉血管内皮细胞粘附实验中,实验组乳腺癌细胞与血管内皮细胞的粘附能力强于对照组(p<0.05);且Western blotting结果显示MMP9和p-FAK蛋白水平明显上升。由以上结果可得出结论,过表达ITGB2后会增强人乳腺癌细胞MCF-7的迁移、侵袭与粘附能力,而对其增殖能力无明显影响。     

过表达胃泌素促进胃癌细胞的增殖、迁移和侵袭

胃癌患者转移淋巴结中胃泌素基因的表达量是原发胃癌组织的42倍,推测胃泌素可能与胃癌转移密切相关. 本文通过构建含胃泌素基因的真核表达载体,成功获得过表达胃泌素的稳转胃癌细胞株AGS和SGC-7901, 并用MTT、细胞伤愈实验、Transwell 小室实验及ELISA检测过表达胃泌素对细胞迁移、侵袭及转移相关蛋白基质金属蛋白酶2（MMP-2）分泌能力的影响. 结果显示,过表达胃泌素稳转细胞的相对增殖率、 迁移入细胞致伤区的相对距离比对照组高,迁移和侵袭到Transwell下室面的细胞, 以及培养液中每mg蛋白质的MMP-2浓度也高于对照组的细胞. 结果提示,胃泌素通过促进胃癌细胞分泌MMP-2来增强细胞的迁移和侵袭能力. 该研究对揭示胃癌转移的分子机制具有重要意义.     

乳腺浸润性导管癌中PTTG与MMP-2和MMP-9 的表达及相关性

垂体瘤转化基因（PTTG）具有促进体外细胞转化和体内致瘤的能力,在乳腺癌组织中高表达,并与乳腺癌的复发和淋巴结转移有关.但PTTG 能否通过调节基质金属蛋白酶(MMP-2、MMP-9) 调控乳腺癌的侵袭与转移尚不清楚.本研究证明,PTTG可能因促进乳腺癌细胞中 MMP-2、MMP-9 分泌而在乳腺癌细胞侵袭、转移中发挥重要作用.免疫组织化学 PV 9000 通用型两步法显示,60例乳腺浸润性导管癌组织中,PTTG、MMP-2 和 MMP-9表达定位于肿瘤细胞胞浆,阳性率与周围正常乳腺组织相比,差异均具有统计学意义(P＜0.05).三者阳性表达均与淋巴结转移及TNM分期有关(P＜0.05);与患者年龄、肿瘤大小等无关(P＞0.05).乳腺浸润性导管癌中PTTG分别与MMP-2、MMP-9的表达呈正相关(P＜0.05).小RNA干扰技术干扰乳腺癌细胞株 MDA-MB-231 中的PTTG,Western印迹结果显示,干扰组与对照组相比,PTTG、MMP-2 和 MMP-9蛋白的表达水平明显下降. Transwell 侵袭实验显示,干扰组肿瘤细胞体外侵袭能力明显降低(P＜0.01).本研究表明,PTTG可能通过促进乳腺癌细胞中 MMP-2、MMP-9分泌,促进乳腺癌细胞的侵袭、转移.     

EBP50通过Wnt3a/β-catenin信号通路抑制乳腺癌细胞的侵袭和转移

EBP50通过抑制LIMK/cofilin信号通路和PI3K/Akt/m TOR/MMP信号通路抑制乳腺癌细胞的侵袭和转移。然而,EBP50是否可以通过其他机制抑制乳腺癌细胞的侵袭和转移尚未可知。本研究发现,EBP50能通过Wnt3a/β-catenin信号通路影响乳腺癌细胞的侵袭和转移。Western印迹结果显示,EBP50在低转移细胞株MCF-7和正常乳腺细胞株MCF-10A中高表达,而在高转移细胞株MDA-MB-231低表达。采用RNAi技术将小RNA质粒瞬时转染乳腺癌细胞株MCF-7,同时将质粒pc DNA3.1-EBP50转入乳腺癌细胞株MDA-MB-231。Western印迹结果显示,Si EBP50/MCF-7细胞组的EBP50表达水平明显下调,MDA231/EBP50细胞组的EBP50表达水平明显上调。Transwell侵袭实验和划痕实验结果显示,用Wnt3a刺激后,Si EBP50/MCF-7细胞组体外迁移和侵袭能力明显增强,MDA231/EBP50细胞组体外迁移和侵袭能力明显减弱。Western印迹结果显示,与未用Wnt3a或同时用Wnt3a和抑制剂Dkk1刺激的相比,Si EBP50/MCF-7细胞组上皮-钙粘蛋白(Ecadherin)下调,波形蛋白(vimentin)上调,细胞核中β-联蛋白(β-catenin)的表达水平升高,而MDA231/EBP50细胞组上皮-钙粘蛋白上调,波形蛋白下调,细胞核中β-联蛋白表达下降。上述结果表明,EBP50通过Wnt3a/β-catenin信号通路影响β-联蛋白的转核,抑制EMT的发生,进而抑制乳腺癌细胞的侵袭和转移。     

过表达外源ST3Gal I增加MCF-7细胞与胞外基质粘附和侵袭能力

为探讨过表达外源α2,3-唾液酸转移酶（ST3Gal Ⅰ）对乳腺癌MCF-7细胞粘 附和侵袭能力的影响,构建pEGFP-N1-ST3Gal I真核表达载体.采用GenEscortTM Ⅱ包裹后转染MCF-7细胞. MCF-7细胞为3组：未转染组 (M)、转染空质粒组 (P) 和转染ST3Gal I组 (ST3); 荧光显微镜观察融合蛋白EGFP ST3Gal I的表达.采用 半定量RT-PCR、Western印迹法分析转染后MCF-7细胞ST3Gal Ⅰ基因mRNA水平和 蛋白表达水平;流式细胞术分析ST3Gal Ⅰ下游产物细胞表面α2,3-唾液酸含量;采用细胞粘附实验及transwell小室检测转染前后细胞与基质胶Matrigel粘附、迁移和侵袭运动能力的变化.结果表明, 荧光显微镜下P组细胞内绿色荧光呈弥散分 布,而ST3组绿色荧光主要集中在细胞质中,RT-PCR与Western印迹也证实了外源 ST3Gal Ⅰ基因mRNA和蛋白表达均明显增加（P<0.05）,其下游产物细胞表面 α2,3-唾液酸含量明显增加（P<0.05）;与M、P组相比,ST3组表现为粘附、迁移和侵袭能力明显增强（P<0.05）.利用转染技术可明显提高外源ST3Gal Ⅰ在MCF -7细胞表达,明显增加MCF-7细胞与胞外基质（ECM）粘附、迁移和侵袭能力,可形成肿瘤入侵表型,将有望成为治疗乳腺癌转移的新靶点.     

过表达P185可抑制EMT并促进胃癌细胞侵袭和迁移

为探究过表达P185基因对胃癌SGC7901细胞侵袭、迁移的影响以及可能作用机制,本研究通过脂质体将携带P185基因的过表达pcDNA3.1-P185质粒,转染至胃癌SGC7901细胞中;本研究采用qRT-PCR和免疫印迹试验(Western blotting)检测P185 mRNA的转录水平和蛋白水平,Western blotting检测钙黏蛋白E(E-cadherin)、波形蛋白(Vimentin)、基质金属蛋白酶-2 (matrix metalloprotease, MMP-2)表达;以Transwell小室法检测细胞的侵袭、迁移能力的变化。研究结果表明:胃癌细胞转染过表达pcDNA3.1-P185质粒能显著上调P185 mRNA和蛋白质的表达(p0.05);SGC7901细胞转染重组质粒pcDNA3.1-P185后,细胞的侵袭、迁移能力较对照组显著增强(p0.05),细胞中E-cadherin蛋白水平显著下调(p0.05),Vimentin、MMP-2蛋白水平显著增加(p0.05)。本研究显示P185可能通过抑制EMT,促进细胞外基质的降解、促进胃癌细胞的侵袭、迁移。     

Exogenous expression of N-cadherin in breast cancer cells induces cell migration, invasion, and metastasis

E- and N-cadherin are calcium-dependent cell adhesion molecules that mediate cell-cell adhesion and also modulate cell migration and tumor invasiveness. The loss of E-cadherin-mediated adhesion has been shown to play an important role in the transition of epithelial tumors from a benign to an invasive state. However, recent evidence indicates that another member of the cadherin family, N-cadherin, is expressed in highly invasive tumor cell lines that lacked E-cadherin expression. These findings have raised the possibility that N-cadherin contributes to the invasive phenotype. To determine whether N-cadherin promotes invasion and metastasis, we transfected a weakly metastatic and E-cadherin-expressing breast cancer cell line, MCF-7, with N-cadherin and analyzed the effects on cell migration, invasion, and metastasis. Transfected cells expressed both E- and N-cadherin and exhibited homotypic cell adhesion from both molecules. In vitro, N-cadherin-expressing cells migrated more efficiently, showed an increased invasion of Matrigel, and adhered more efficiently to monolayers of endothelial cells. All cells produced low levels of the matrix metalloproteinase MMP-9, which was dramatically upregulated by treatment with FGF-2 only in N-cadherin-expressing cells. Migration and invasion of Matrigel were also greatly enhanced by this treatment. When injected into the mammary fat pad of nude mice, N-cadherin-expressing cells, but not control MCF-7 cells, metastasized widely to the liver, pancreas, salivary gland, omentum, lung, lymph nodes, and lumbar spinal muscle. The expression of both E- and N-cadherin was maintained both in the primary tumors and metastatic lesions. These results demonstrate that N-cadherin promotes motility, invasion, and metastasis even in the presence of the normally suppressive E-cadherin. The increase in MMP-9 production by N-cadherin-expressing cells in response to a growth factor may endow them with a greater ability to penetrate matrix protein barriers, while the increase in their adherence to endothelium may improve their ability to enter and exit the vasculature, two properties that may be responsible for metastasis of N-cadherin-expressing cells.     

Leucine aminopeptidase 3 promotes migration and invasion of breast cancer cells through upregulation of fascin and matrix metalloproteinases-2/9 expression

Overexpression of leucine aminopeptidase 3 (LAP3) is involved in proliferation, migration, and invasion of several tumor cells and plays a crucial role in tumor metastasis. However, the related mechanism remains unknown. In this study, we used MDA-MB-231 and MCF7 breast cancer cell lines to explore the role of LAP3 in the regulation of cancer cell migration and invasion by employing the natural LAP3 inhibitor bestatin and a lentivirus vector that overexpresses or knocks down LAP3. Bestatin inhibited tumor cell migration and invasion in a dose-dependent manner. Western blot assay showed that bestatin and knockdown of LAP3 upregulated phosphorylation of Hsp27 and downregulated expression of fascin. Phosphorylation of Akt and expression of matrix metalloproteinase-2/9 can also be downregulated. LAP3 overexpression showed the opposite results. Immunohistochemistry analysis was conducted to detect expression levels of LAP3 in breast cancer tissues. High LAP3 expression was correlated with the grade of malignancy. Findings of this study uncovered the molecular mechanism of LAP3 on breast cancer metastasis and indicated that LAP3 may act as a potential antimetastasis therapeutic target.     

同型半胱氨酸对A7r5细胞增殖及MMP-9表达的影响

观察同型半胱氨酸（Hcy）对大鼠胸主动脉平滑肌细胞（A7r5细胞）增殖及对基质金属蛋白酶9（MMP-9）表达的影响。0.25、0.50和1.00 mmol/LHcy分别作用A7r5细胞48 h,倒置显微镜下观察细胞的形态学改变;RT-PCR检测MMP-9 mRNA的表达,Western blot检测MMP-9蛋白的表达。随着Hcy浓度的升高,细胞数目逐渐增多,体积增大,生长旺盛,呈增殖表现。不同浓度Hcy处理组MMP-9 mRNA及蛋白的表达均逐渐增加,各实验组与对照组差异均有统计学意义（P〈0.05）。同时显示正常对照组中MMP-9表达相对较少,为（3.60±1.42）%、（1.60±0.82）%。Hcy能促进A7r5细胞增殖,正常A7r5细胞中MMP-9表达较少;Hcy可诱导A7r5细胞MMP-9的表达,这一效应可能是Hcy致心血管疾病的分子机制之一。提示MMP-9可能成为干预心血管疾病的靶点。     

Sprouty2蛋白与人乳腺癌MCF-7细胞增殖与迁徙的关系

目的：探讨Sprouty2蛋白与人乳腺癌MCF-7细胞增殖与迁徙的关系。方法：通过siRNA技术干扰MCF-7细胞sprouty2基因的表达,通过qPCR,细胞免疫荧光和westernblotting检测sprouty2基因的干扰效果,MTT检测细胞增殖活力,划痕实验观察细胞迁徙能力,westernblotting检测MMP-2,MMP-9和MMP-13的表达。结果：qPCR,细胞免疫荧光和westernblotting检测sprouty2基因,发现sprouty2基因的下调很明显,MTT实验发现siRNASprouty2基因后的MCF-7细胞比对照组细胞活力明显提高,沉默组细胞的迁徙能力也明显强于对照组,且沉默sprouty2基因的MCF-7细胞,MMP-2,MMP-9和MMP-13蛋白相对对照组均上调。结论：sprouty2基因下调后,MCF-7细胞的细胞活力和迁徙能力明显提高。     

IL-8对肺腺癌A549细胞迁移的影响及其机制探讨

探讨IL-8对肺腺癌A549细胞迁移的影响及其可能机制。用MTT法选择了合适的IL-8使用浓度。分别用划痕试验及Transwell试验证明了IL-8可以促进肺腺癌A549细胞的迁移。Westernblot结果表明:(1)IL-8可以促进MMP-2蛋白的表达,而对MMP-9的表达无明显影响;(2)IL-8可促进JNK/SAPK磷酸化蛋白的表达;(3)抑制剂(SP600125)可以阻断IL-8对MMP-2蛋白表达的影响。划痕试验从反面验证了低表达的MMP-2可以抑制A549细胞的迁移。表明IL-8可通过JNK/SAPK信号通路调控MMP-2蛋白的表达,进一步促进肺腺癌A549细胞的迁移。     

Interaction of keratinocytes and fibroblasts modulates the expression of matrix metalloproteinases-2 and -9 and their inhibitors

Disruption of epidermal-mesenchymal communication due to a delay in epithelialization, increases the frequency of developing fibrotic conditions in skin. As matrix metalloproteinases-2 (MMP-2) and -9 (MMP-9) are two key enzymes involved in wound healing and tissue remodeling, here we examined the efficacy of keratinocyte-fibroblast interaction on modulation of these enzymes and their inhibitors. The conditioned media derived from keratinocytes and fibroblasts grown in upper and lower chambers of a co-culture system, respectively, were analyzed for MMP-2 and -9. Keratinocyte or fibroblast conditioned medium (FCM) was used as a control. Gelatinolytic activity analyzed by zymography showed that keratinocytes mainly express MMP-9 and to a lesser extent MMP-2; while fibroblasts express only MMP-2. In a co-culture system, the activities of both MMP-2 and MMP-9 markedly increased in conditioned media collected from bottom chambers. These findings were consistent with the level of MMP-2 and MMP-9 measured by Western blot. Using the same experimental setting, the levels of tissue inhibitors of MMPs (TIMPs) secreted by keratinocytes and fibroblasts grown in the same co-culture system were also evaluated. Western blot showed that fibroblasts secrete only TIMP-1 and TIMP-2 whose levels were increased by co-culturing fibroblasts with keratinocytes. In contrary the level of TIMP-3, which was mainly expressed by keratinocytes, increased by co-culturing these cells with fibroblasts. In conclusion, interaction of fibroblast-keratinocyte modulates the levels of MMP-2 and -9 and their inhibitors produced by these cells and this interaction may be critical for a better healing quality at a late stage of the wound healing process. (Mol Cell Biochem 269: 209–216, 2005)     

Effects of E-cadherin on mouse embryo implantation and expression of matrix metalloproteinase-2 and -9

E-cadherin is a cell surface glycoprotein, which is responsible for adhesion between epithelial cells. Whether it is involved in embryo implantation is still unknown. In a mouse intrauterine horn injection model, one uterine horn in each mouse was injected with different doses of E-cadherin antibody on day 3 of pregnancy. The results showed that embryo implantation was significantly inhibited in the mice injected with 3 microg E-cadherin antibody. The mouse uteri in this group were collected on days 5, 6, and 7 of pregnancy and expressions of MMP-2 and -9 were studied. In situ hybridization and RT-PCR results showed that the expression of MMP-2 and -9 mRNAs in uteri of E-cadherin antibody treated group was increased on days 5-7. The results of gelatin zymography of MMPs showed that the activities of pro-MMP-2, MMP-2, and pro-MMP-9 were increased significantly on days 5 and 6, and pro-MMP-9 activity was increased on day 7. The present study suggested that E-cadherin was involved in embryo implantation through decreasing the expressions and activities of MMP-2 and -9.