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1.
Melittin is the predominant component of bee venom with cell membrane-disrupting capability. To release melittin on cell surfaces to destroy tumor cell membranes, we designed a recombinant targeting toxin with an uPA cleavable link. It contains A Disintegrin-like domain of ADAM 15 to selectively deliver fusion protein to the surface of the tumor cells expressing integrin αvβ3, a toxin domain consisting of four repeats of N-terminal 22 amino acids of melittin, and an uPA cleavable link in between. The fusion protein named as ADAM-Conj-Mel was successfully expressed in Escherichia coli and can be cleaved by uPA as well as conditioned medium of SW1990 tumor cells. In vitro, ADAM-Conj-Mel efficiently inhibits proliferation of human melanoma (C32) tumor cells. In vivo, it reduces B16 tumor volume by approximately 80%. Our data suggested that ADAM-Conj-Mel is a protein with potential in clinical development for cancer therapy.  相似文献   

2.
尿激酶型纤溶酶原激活系统(uPA)在骨性关节炎的病理过程中发挥着重要的调控作用.其与骨性关节炎的发病,发展以及结局息息相关;骨性关节炎的治疗也是围绕其展开.近年来.围绕着uPA系统探索骨性关节炎的发病机制及治疗已成为基础和临床研究的热点.本文将uPA系统在骨性关节炎中的作用及骨性关节炎的治疗予以综述.  相似文献   

3.
杜文丙  尹来波  刘维钢  赵咏梅  卢慧 《生物磁学》2009,(20):3874-3876,F0003
目的:通过不同浓度外源性尿激酶型纤溶酶原激活剂(uPA)兔椎间盘内注射,探讨uPA对椎间盘作用。方法:健康大白兔72只,随机分为实验组48只,阴性对照组16只,空白对照组8只。实验组:分为三个亚组,L4/5椎间盘内分别注射浓度为10、20、40ng/μl的uPA各1μl。阴性对照组:椎间盘内注射1μl的生理盐水。空白对照组:不作任何处理。分别于第3、6周取相应椎间盘,大体观察、HE染色、SABC法测基质金属蛋白酶-3(MMP-3)的表达及蛋白多糖含量测定。结果:实验组MMP.3表达显著增强,蛋白多糖含量明显降低,与同期对照组比较(P〈0.05),有显著统计学意义。实验组在不同时间及不同浓度比较也有统计学意义。结论:外源性uPA能够导致兔椎间盘内蛋白多糖含量降低,MMP-3表达显著增强,可能在椎间盘退变过程中其重要作用。  相似文献   

4.
核酸分子杂交是从cDNA或基因组DNA文库中筛选目的基因的最为敏感而特异的方法。为了从人胚肾细胞cDNA文库和人胚食道粘膜细胞基因组文库,筛选含有人尿激酶型血纤维蛋白溶酶原激活剂(简称uPA)基因序列的克隆,我们分别从F.Blasi和Y.Nagamine获得了含有人uPA cDNA 1500bp片段的重组质粒pHUK-8转化的E.coli HBl 01菌株,以及含有猪uPA全长cDNA 2375 bp片段的重组质粒pYN-15菌株。如果二者的uPA cDNA片段具有同源性,则皆可作为探针  相似文献   

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6.
尿激酶型纤溶酶原激活物 (uPA)是参与细胞外基质降解的重要成分 ,在肿瘤细胞的侵袭和转移中起着重要作用。人们对uPA的结构、功能以及它与纤溶酶原激活抑制物 1 (PAI 1 )、uPA受体 (uPAR)的相互作用都进行了深入的研究。单链uPA是一种糖蛋白 ,含有 41 1个氨基酸。其结构可分为四部分 ,依次为 :上皮生长因子区、环状结构区、连接区和丝氨酸蛋白酶区。纤溶酶可裂解Lys1 5 8 Ile1 5 9之间的肽键 ,使单链uPA转变为双链uPA。uPA与其细胞表面受体结合后激活纤溶酶原 ,自身激活也增强。结合在细胞膜上的uPA…  相似文献   

7.
针对uPA的siRNA对人乳腺癌细胞侵袭的抑制作用   总被引:1,自引:1,他引:0  
目的:通过RNA干涉的方法抑制乳腺癌细胞中uPA的表达,观察uPA的表达抑制后对肿瘤细胞的体外侵袭能力的影响。方法:(1)构建可以表达针对uPA的siRNA的干涉载体,转染高侵袭性人乳腺癌细胞系MDA-MB231,G418抗性筛选,挑选单克隆株;(2)分别通过RT-PCR和WesternBlot的方法检测uPA的表达;(3)平板克隆形成试验检测转染前后肿瘤细胞的克隆形成能力;4BovdenchamberAssay检测肿瘤细胞体外侵袭能力。结果:(1)可以稳定表达针对uPA的siRNA的单克隆株,uPA的表达水平显著下降;(2)转染了针对uPA的siRNA的单克隆株的克隆形成能力降低;(3)转染了针对uPA的siRNA的单克隆株体外侵袭能力与原代细胞MDA-MB231相比明显受到抑制。结论:uPA在人乳腺癌侵袭行为中发挥重要的作用,针对uPA的siRNA可以显著降低uPA的表达,从而抑制肿瘤细胞的侵袭,可望成为抗肿瘤侵袭治疗的一种有效手段。  相似文献   

8.
石静  鞠放  清水汪  冯丹  颜芳  王宁  王雅杰 《生物磁学》2011,(21):4058-4060
目的:探讨血浆uPA、uPAR在不同分子亚型乳腺癌中的表达水平及其对乳腺癌患者治疗、预后等的临床意义。方法:采用免疫组化ELISA方法测定的女性乳腺癌初治患者86例的血浆uPA、uPAR水平,所有患者均经组织病理学确诊,以患者的临床病理学资料提供的免疫组化结果为基础进行分子分型,结合二者进行分析。结果:血浆uPA在乳腺癌不同分子亚型中表达有统计学差异(P〈0.01),uPAR在乳腺癌不同分子亚型中表达有统计学差异(P〈0.05);乳腺癌患者血浆uPA和uPAR呈显著正相关(P〈0.01,Pearson相关系数(r=0.735)。结论:乳腺癌患者血浆uPA和uPAR的水平与分子亚型密切相关,他们和分子亚型联合,可能对乳腺癌个体化治疗及判定预后有指导意义。  相似文献   

9.
目的:探讨血浆uPA、uPAR在不同分子亚型乳腺癌中的表达水平及其对乳腺癌患者治疗、预后等的临床意义。方法:采用免疫组化ELISA方法测定的女性乳腺癌初治患者86例的血浆uPA、uPAR水平,所有患者均经组织病理学确诊,以患者的临床病理学资料提供的免疫组化结果为基础进行分子分型,结合二者进行分析。结果:血浆uPA在乳腺癌不同分子亚型中表达有统计学差异(P<0.01),uPAR在乳腺癌不同分子亚型中表达有统计学差异(P<0.05);乳腺癌患者血浆uPA和uPAR呈显著正相关(P<0.01,Pearson相关系数r=0.735)。结论:乳腺癌患者血浆uPA和uPAR的水平与分子亚型密切相关,他们和分子亚型联合,可能对乳腺癌个体化治疗及判定预后有指导意义。  相似文献   

10.
利用基因重组技术,用RT-PCR法从幼鼠肾脏获得uPA cDNA,再克隆到质粒pAAV-IRES-hrGFP的多克隆位点,构建重组质粒pAAV-hrGFP-uPA,通过酶切和DNA测序鉴定重组质粒的正确性,采用磷酸钙共沉淀法,以重组质粒pAAV-hrGFP-uPA和pAAV-RC、pHelper共转染AAV-293细胞,产生具有传染性的病毒颗粒;用斑点杂交法测定重组病毒颗粒的滴度,再将此病毒颗粒体外转染到培养的肾小管细胞中,倒置荧光显微镜观察GFP的表达,用免疫组化法检测转染的uPA蛋白表达,结果表明:成功地构建uPA基因GFP-腺相关病毒重组质粒,病毒滴度达每mL 4×10^13病毒颗粒,60%~70%肾小管细胞感染了病毒颗粒,感染的肾小管细胞能稳定、高效表达外源uPA蛋白,为今后建立AAV-uPA基因治疗肾纤维化的模型奠定了良好的基础.  相似文献   

11.
目的:研究uPA和uPAR在卵巢癌中的表达,分析其与卵巢癌的发展和预后的关系。方法:采用免疫组织化学法检测60例上皮性卵巢癌、20例交界性卵巢肿瘤及20例良性卵巢肿瘤组织中uPA、uPAR及表达,并结合临床病理因素进行分析。结果:(1)uPA、uPAR、在上皮性卵巢癌中的表达率(75%,66.7%)明显高于交界性卵巢肿瘤(40%,30%)及良性卵巢肿瘤组织(30%,25%),差异均有统计学意义(uPAx2=22.078,P0.001;uPARx2=19.510,P0.05),而交界性卵巢肿瘤与良性卵巢肿瘤组织间差异无统计学意义(P0.05)。(2)uPA、uPAR在恶性卵巢肿瘤中阳性表达率与手术病理分期、组织分级和有无淋巴结转移有关;晚期癌组阳性表达率高于早期癌组(uPAx2=14.400,P0.05;uPARx2=9.6,P=0.002);低分化癌组的阳性表达率高于中高分化癌(uPAx2=15.002,P0.05;uPARx2=36.906,P0.05);有淋巴结转移癌组阳性表达率高于无淋巴结转移癌组(uPAx2=13.333,P0.05;uPARx2=15.313,P0.05);差异均有统计学意义;但是与癌症病理类型、病人年龄、肿瘤大小无关。uPA与uPAR的表达存在正相关。结论:在uPA和uPAR可通过促进血管生成和降解细胞外基质(基质)和基底膜,在肿瘤的侵袭和转移中发挥重要作用。uPA及uPAR在上皮性卵巢癌组织中表达上调,支持这些因子在肿瘤浸润和转移中发挥重要作用,二者有可能作为预测上皮性卵巢癌预后的重要参考指标。  相似文献   

12.
Activating K-Ras mutations and inactivating mutations of Smad4 are two common genetic alterations that occur in the development and progression of pancreatic ductal adenocarcinomas (PDAC). To further study the individual and combinatorial roles of these two mutations in the pathogenesis of PDAC, immortalized human pancreas nestin postive cells (HPNE) were genetically modified by either expressing oncogenic K-Ras (HPNE/K-Ras), by shRNA knock down of Smad4 (HPNE/ShSmad4) or by creating both alterations in the same cell line (HPNE/K-Ras/ShSmad4). We previously found that expression of oncogenic K-Ras caused an increase in expression of EGFR and loss of Smad4 further enhanced the up regulation in expression of EGFR and that this increase in EGFR was sufficient to induce invasion. Here we further investigated the mechanism that links mutational alterations and EGFR expression with invasion. The increase in EGFR signaling was associated with up regulation of MMP9 and uPA protein and activity. Moreover, the increase in EGFR signaling promoted a nuclear translocation and binding of RelA (p65), a subunit of NF-κB, to the promoters of both MMP-9 and uPA. Treatment of HPNE/K-Ras/ShSmad4 cells with an inhibitor of EGFR reduced EGF-mediated NF-κB nuclear translocation and inhibitors of either EGFR or NF-κB reduced the increase in MMP-9 or uPA expression. In conclusion, this study provides the mechanism of how a combination of oncogenic K-Ras and loss of Smad4 causes invasion and provides the basis for new strategies to inhibit metastases.  相似文献   

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14.
The uPAR·uPA protein–protein interaction (PPI) is involved in signaling and proteolytic events that promote tumor invasion and metastasis. A previous study had identified 4 (IPR-803) from computational screening of a commercial chemical library and shown that the compound inhibited uPAR·uPA PPI in competition biochemical assays and invasion cellular studies. Here, we synthesize 4 to evaluate in vivo pharmacokinetic (PK) and efficacy studies in a murine breast cancer metastasis model. First, we show, using fluorescence polarization and saturation transfer difference (STD) NMR, that 4 binds directly to uPAR with sub-micromolar affinity of 0.2 μM. We show that 4 blocks invasion of breast MDA-MB-231, and inhibits matrix metalloproteinase (MMP) breakdown of the extracellular matrix (ECM). Derivatives of 4 also inhibited MMP activity and blocked invasion in a concentration-dependent manner. Compound 4 also impaired MDA-MB-231 cell adhesion and migration. Extensive in vivo PK studies in NOD-SCID mice revealed a half-life of nearly 5 h and peak concentration of 5 μM. Similar levels of the inhibitor were detected in tumor tissue up to 10 h. Female NSG mice inoculated with highly malignant TMD-MDA-MB-231 in their mammary fat pads showed that 4 impaired metastasis to the lungs with only four of the treated mice showing severe or marked metastasis compared to ten for the untreated mice. Compound 4 is a promising template for the development of compounds with enhanced PK parameters and greater efficacy.  相似文献   

15.
目的:检测子宫内膜癌组织中尿激酶型纤溶酶原激活物(uPA)及组织蛋白酶(Cath-D)的表达并探讨相关性及其临床意义。方法:采用免疫组织化学方法(PV-6000二步法)检测31例子宫内膜癌组织(内膜癌组),17例子宫内膜增生组织(增生组)及10例正常子宫内膜组织(对照组)中uPA及Cath-D的表达,并研究其相关性。结果:1.内膜癌组中uPA和Cath-D的表达均高于增生组及对照组中的表达,差异均有统计学意义(P0.05);在增生组中的表达与对照组差异无统计学意义(P0.05)。2.uPA和Cath-D的阳性表达与子宫内膜癌的临床病理分期、组织学分级及肌层浸润深度有关,差异均具有统计学意义(P0.05)。3.内膜癌组中uPA与Cath-D的表达呈正相关(r=0.673,P0.05)。结论:uPA和Cath-D在子宫内膜癌发生发展及侵袭转移过程中起着协同作用,Cath-D可诱导产生活化的uPA,促进癌细胞的浸润转移,因此,两者的联合检测可有助于成为判断子宫内膜癌的发展及预后的重要指标。  相似文献   

16.
BackgroundProstate cancer (PCa) is one of the most commonly encountered cancers and the leading cause of death worldwide. Currently used biomarkers accounts difficulties in discriminating benign from malignant cases or predicting outcome, so investigating new biomarkers performance is needed.ObjectivesAssessment of diagnostic and predictor roles of prostate health index (PHI) and urokinase plasminogen activator (uPA) in PCa.Methods194 males with initial tPSA of 4–10 ng/mL were categorized into three groups: PCa, benign prostatic hyperplasia (BPH) and healthy control. Serum levels of tPSA, fPSA, p2PSA, and uPA were performed by ELISA with calculation of PHI as (p2PSA/fPSA) × √PSA.ResultsPHI and uPA were significantly higher in PCa patients relevant to BPH and healthy control (p ≤ 0.001). Both markers outperformed all assessed biomarkers and showed the highest area under the curve (AUC) in ROC curve analysis. Both were significantly higher in PCa patients with {Gleason score ≥ 7, late stages (cT2b,c; T3), LN extension and distant metastasis}relative to their counterparts. Additionally, PHI and uPA and were independent predictors of distant metastasis and Gleason score ≥ 7, while PHI was predictor of LN invasion (β = 0.25, p = 0.004).ConclusionPHI and uPA would be of potential value in discriminating between PCa, BPH and healthy men in addition, both are promising as independent predictors of adverse pathological features.  相似文献   

17.
Metformin has been shown to exert anti-cancer activities in several cancer cells and animal models. However, the molecular mechanisms of its anti-metastatic activities remain poorly understood and warrant further investigation. The aims of this study were to evaluate the ability of metformin to inhibit the migration and invasion of hepatocellular carcinoma (HCC) cells and identify its effects on signaling pathways. Our data indicate that metformin inhibits the migration and invasion of human HCC cells. Metformin was also found to significantly inhibit the expression and secretion of MMP-9 and uPA in HCC cells, and suppress the phosphorylation of ERK1/2 and JNK1/2. Treatment with an ERK1/2 inhibitor (PD98059) or JNK1/2 inhibitor (SP600125) enhanced the inhibitory effects of metformin on the migration and invasion of HCC cells. Moreover, metformin-induced inhibition of MMP-9 and uPA promoter activity also blocked the nuclear translocation of NF-κB and its binding to the MMP-9 and uPA promoters, and these suppressive effects were further enhanced by PD98059 or SP600125. Moreover, metformin markedly enhanced the anti-metastatic effects of sorafenib. In conclusion, metformin inhibits the migration and invasion of HCC cells by suppressing the ERK/JNK-mediated NF-κB-dependent pathway, and thereby reducing uPA and MMP-9 expression. Additionally, combination treatment with metformin and sorafenib yielded synergistic inhibitory effects in suppressing cell migration and invasion of HCC cells. These findings provide insight into the molecular mechanisms involved in the anti-metastatic effects of metformin, as well as its ability to enhance the chemosensitivity of HCC cells to sorafenib.  相似文献   

18.
Myofibroblasts (Mfs) that persist in a healing wound promote extracellular matrix (ECM) accumulation and excessive tissue contraction. Increased levels of integrin αvβ5 promote the Mf phenotype and other fibrotic markers. Previously we reported that maintaining uPA (urokinase plasminogen activator) bound to its cell-surface receptor, uPAR prevented TGFβ-induced Mf differentiation. We now demonstrate that uPA/uPAR controls integrin β5 protein levels and in turn, the Mf phenotype. When cell-surface uPA was increased, integrin β5 levels were reduced (61%). In contrast, when uPA/uPAR was silenced, integrin β5 total and cell-surface levels were increased (2-4 fold). Integrin β5 accumulation resulted from a significant decrease in β5 ubiquitination leading to a decrease in the degradation rate of internalized β5. uPA-silencing also induced α-SMA stress fiber organization in cells that were seeded on collagen, increased cell area (1.7 fold), and increased integrin β1 binding to the collagen matrix, with reduced activation of β1. Elevated cell-surface integrin β5 was necessary for these changes after uPA-silencing since blocking αvβ5 function reversed these effects. Our data support a novel mechanism by which downregulation of uPA/uPAR results in increased integrin αvβ5 cell-surface protein levels that regulate the activity of β1 integrins, promoting characteristics of the persistent Mf.  相似文献   

19.
目的:探讨尿激酶型纤溶酶原激活剂(uPA)、纤溶酶原激活物抑制剂(PAI-1)的表达和血管形成与浸润性乳腺癌侵袭性的关系。方法:应用免疫组化SP法检测80例浸润性乳腺癌、20例良性乳腺肿瘤组织中uPA、PAI-1的表达情况并进行微血管计数。结果:uPA和PAI-1在浸润性乳腺癌组的阳性表达显著高于良性肿瘤组,且其高表达率与乳腺癌的临床病理参数密切相关(P<0.05);微血管计数在乳腺癌组和良性肿瘤组分别为30.87±7.64、20.28±8.72,两组比较有显著性差异(P<0.01)。uPA与PAI-1在浸润性乳腺癌中的表达呈正相关(P<0.05)。结论:uPA、PAI-1的高表达与浸润性乳腺癌的浸润、转移相关,uPA、PAI-1的高表达和MVD计数可作为评价浸润性乳腺癌侵袭性、评估预后和确定治疗方案的生物学指标。  相似文献   

20.
陈旭伟  孙伟  崔世义 《生物磁学》2011,(12):2307-2309
目的:探讨尿激酶型纤溶酶原激活剂(uPA)、纤溶酶原激活物抑制剂(PAI-1)的表达和血管形成与浸润性乳腺癌侵袭性的关系。方法:应用免疫组化SP法检测80例浸润性乳腺癌、20例良性乳腺肿瘤组织中uPA、PAI-1的表达情况并进行微血管计数。结果:uPA和PAI-1在浸润性乳腺癌组的阳性表达显著高于良性肿瘤组,且其高表达率与乳腺癌的临床病理参数密切相关(P〈0.05);微血管计数在乳腺癌组和良性肿瘤组分别为30.87±7.64、20.28±8.72,两组比较有显著性差异(P〈0.01)。uPA与PAI-1在浸润性乳腺癌中的表达呈正相关(P〈0.05)。结论:uPA、PAI-1的高表达与浸润性乳腺癌的浸润、转移相关,uPA、PAI-1的高表达和MVD计数可作为评价浸润性乳腺癌侵袭性、评估预后和确定治疗方案的生物学指标。  相似文献   

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