uPA/uPAR/PAI与消化系统肿瘤

消化系统肿瘤在我国的肿瘤发病率中占第1位.从尿激酶型纤溶酶原激活物受体(urokinase plasminogen activator receptor, uPAR)首次被描述为尿激酶型纤溶酶原激活物(urokinase plasminogen activator, uPA)链的细胞表面高亲和性激活剂以来,越来越受到研究者的关注.研究表明:uPA,uPAR及尿激酶型纤溶酶原激活物抑制剂(urokinase plasminogen activator inhibitor, PAI)与消化系统肿瘤侵袭和转移密切相关.本文对uPA,uPAR及PAI与胃癌、食管癌、结肠癌、肝癌、胰腺癌等侵袭与转移的关系进行综述.     

uPA/uPAR/PAI系统与炎性关节疾病

近年来研究表明,尿激酶型纤溶酶原激活剂(urokinase-type plasminogen activator,uPA)/尿激酶型纤溶酶原激活剂受体(uPA receptor,uPAR)/纤溶酶原激活剂抑制剂(plasminogen activator inhibitor,PM)系统与炎性关节疾病中滑膜增生以及关节软骨和骨的破坏密切相关,本文就近年来的研究进展作一综述,旨在为炎性关节疾病的防治寻找新的靶点和途径.     

多囊卵巢综合征患者血PAI-1和uPA含量的变化

目的观察多囊卵巢综合征(PCOS)患者外周血纤溶酶原激活抑制物1(PAI-1)和尿激酶型纤溶酶原激活物(uPA)的水平。方法实验分PCOS组和对照组,PCOS组又分为肥胖组和正常体重组,用酶联免疫吸附法(ELISA)测定PCOS组与对照组患者血浆PAI-1及血清uPA水平,并测定体重指数(BMI)、腰臀比(WHR)、空腹血糖(FPG)、空腹胰岛素及胰岛素释放试验(IRT),以稳态模型公式评估胰岛素抵抗(IR),并计算胰岛素曲线下面积(AUC)。结果PCOS组与对照组相比,黄体生成素/卵泡刺激素(LH/FSH)、睾酮(T)、空腹血糖、稳态(HOMA)指数、AUC及PAI-1含量均显著升高(P<0.05)。其中,PCOS肥胖组与正常体重组相比,HOMA指数、AUC及PAI-1含量也显著升高(P<0.05)。在相关性分析中,PAI-1与HOMA指数、PAI-1与AUC、PAI-1与BMI、HOMA-IR与BMI均有显著相关性(P<0.0001)。结论胰岛素抵抗和肥胖是影响PCOS患者PAI-1水平升高的一个很重要因素,抗PAI-1的研究可能为多囊卵巢综合征的治疗提供一个新的方法。     

uPA和PAI-1在肺纤维化中的作用

慢性炎症和纤维化疾病都以炎性细胞和介质的聚集为特征 ,并且细胞外基质及纤溶酶系统均有明显的改变。目前发现 ,纤溶酶原激活系统的改变是肺纤维化发展中一个非常关键的环节。研究表明各种肺纤维化患者的支气管灌洗液 (BAL)中纤溶酶原活性受到的损害往往是由于尿激酶型纤溶酶原激活物 (uPA)缺失 ,以及纤溶酶原激活因子抑制物 1(PAI 1)表达增加所致。     

肝癌细胞株雌二醇与uPAR表达的关系

目的 观察人肝癌BEL-7402细胞株中雌二醇与uPAR表达的关系。方法 将肝癌BEL-7402细胞株培养于不同浓度雌二醇的培养液中，培养24h、48h及72h后收集各组细胞。通过免疫组化实验，检测各组细胞uPAR的表达。结果 雌二醇作用后的BEL-7402细胞uPAR表达的阳性率明显高于对照组（P〈0．05）。结论 雌二醇可促进肝癌BEL-7402细胞株uPAR的表达。     

血清中尿激酶型纤溶酶原激活物在女性乳腺癌诊断中的应用

近年来,在我国京津沪地区,乳腺癌发病率已居于妇女恶性肿瘤首位川.研究表明,癌细胞在浸润转移的过程中存在着细胞外基质(extracellularmatrix,ECM)和基底膜成分被相关蛋白酶溶解的活动,纤溶酶原激活在ECM水解过程中起重要作用.     

尿激酶型纤溶酶原激活物受体及可溶性尿激酶型纤溶酶原激活物受体与炎症相关的研究进展

尿激酶型纤溶酶原激活物受体（urokinase plasminogen activator receptor,uPAR）与尿激酶型纤溶酶原激活物（urokinase plasminogen activator,uPA）同为纤溶酶原激活系统的主要成员,是一种协调多种信号转导途径的多功能分子,可溶性尿激酶型纤溶酶原激活物受体（soluble urokinase plasminogen activator receptor,suPAR）是其可溶形式。除凝血-纤溶以外,uPAR参与了肿瘤侵袭及炎症等多种疾病过程,而suPAR可能是一种良好的炎性标志物。本文就uPAR及suPAR在炎症中的作用进行简要综述。     

尿激酶型纤溶酶原激活物及其特异受体和抑制物与肺癌的浸润转移

研究尿激酶型纤溶酶原激活物(uPA)及其特异受体(uPA-R)和抑制物(PAI-1、PAI-2)在肺癌浸润转移中的作用.应用RIA分别对67例经组织病理确诊的各期肺癌和30例肺部相关炎症患者及30名健康献血者进行了相应的检测.结果显示,小细胞肺癌Ⅱ期和Ⅲ期患者血浆中uPA、uPA-R、PAI-1水平显著升高(P＜0.001),而PAI-2的水平逐渐降低;腺癌、鳞癌伴有浸润主支气管及肺门淋巴结者uPA、uPA-R与PAI-1水平亦显著升高(P＜0.001);周围型肺癌未见淋巴结受侵者uPA、uPA-R、PAI-1与PAI-2水平异常升高.uPA、uPA-R与PAI-1在肺癌中水平明显升高,并与肺癌的浸润转移相关密切,可作为肿瘤患者早期诊断、预后评估的有力指标.     

uPA和PAI-1在人脑胶质瘤的表达及其与肿瘤血管生成的关系

目的探讨uPA、PAI鄄1和VEGF与人脑胶质瘤病理分级和侵袭行为的关系及各因子间的相互联系。方法采用免疫组化SP方法检测42例人脑胶质瘤和8例正常脑组织uPA、PAI鄄1和VEGF蛋白的表达。结果12例中低度恶性胶质瘤中,uPA、PAI鄄1和VEGF阳性表达率分别为58.3%、50.0%、33.3%,30例高度恶性胶质瘤的阳性率分别为96.7%、86.7%、93.3%,两组间各指标相比较,uPA和VEGF差异有极显著性(P<0.01),PAl鄄1差异有显著性(P<0.05)。uPA、PAI鄄1和VEGF阳性染色主要定位于血管内皮细胞和瘤细胞胞浆,以肿瘤侵袭边缘和坏死组织周围多见。uPA与VEGF、PAI鄄1与VEGF之间均呈明显正相关(P<0.05)。8例正常脑组织除1例有PAl鄄1微弱表达外,其余均为阴性。结论随脑胶质瘤恶性度增高,uPA、PAl鄄1和VEGF表达增强,三者协同作用,可作为胶质瘤恶性度高和侵袭能力强潜在的分子生物学指标。     

uPA与ER在乳腺癌组织中的表达及相关性分析

目的研究雌激素受体（ER）与尿激酶型纤溶酶原激活物（urokinasc-type plasminogen activator,uPA）在乳腺癌组织中的表达及其临床意义。方法免疫组织化学染色采用PV-6000二步法,对40例乳腺癌蜡块中ER、uPA表达进行研究。结果乳腺腺瘤、腺病和乳腺癌中ER阳性率分别为85.O％、82.5％和60.6％,三者差异有统计学意义（P〈O.05）;ER表达阳性患者淋巴结转移率（33.33％）低于ER表达阴性者（81.25％）,差异有统计学意义（P〈O.01）。uPA在乳腺纤维腺瘤、腺病均呈阴性表达,在乳腺癌中的阳性率为60.00％,三者差异有统计学意义（P〈0.05）;uPA表达阳性患者淋巴结转移率（88.5％）显著高于阴性者（50.O％）,两者的表达差异有统计学意义（P〈O.05）。结论uPA的高表达和ER的缺失表达与乳腺癌的浸润转移密切相关,检测ER和uPA对临床选择治疗方法有指导意义。     

Urokinase-type plasminogen activator receptor in gastric cancer: tissue expression and prognostic role

The urokinase-type plasminogen activator (UPA) and its inhibitor PAI-1 are thought to play an important part in gastric cancer (GC) invasion and metastasis. Little is known about the behavior and prognostic impact of the receptor for UPA (UPAR). The aims of the present study were: (1) to measure UPAR, UPA and PAI-1 levels in GC and in non-malignant tissue distant from the tumor (NORM); (2) to evaluate their relationship with histomorphological parameters; and (3) to determine their prognostic value. UPAR, UPA and PAI-1 levels were determined by ELISA in GC and NORM samples from 20 patients with GC undergoing surgery. The GC was also examined in terms of the presence (n=10) or absence (n=10) of metastasis, differentiation (five differentiated, 15 undifferentiated) and histotype. Survival was analysed using life table analysis. UPAR, UPA and PAI-1 were significantly higher in GC vs NORM, in the presence of metastasis (UPAR, UPA) and in undifferentiated GC (UPAR, PAI-1). UPAR significantly correlated with UPA and PAI-1. Low levels of UPAR (P=0.04), UPA (P=0.007) and PAI-1 (P=0.02) were associated with a better survival. Our results demonstrate a sharp increase in UPAR in GC and suggest a prognostic role for it. The concomitant activation of UPAR, UPA and PAI-1 in GC confirm the important role of the plasminogen activator system in the process of invasion and metastasis.     

胃癌中uPA、PAI-1表达及其与血管生成的关系

目的 观察胃癌组织中uPA、PAI-1mRNA及蛋白的表达，并探讨它们与肿瘤分化、血管生成及临床病理因素之间的关系。方法 用原位杂交及免疫组化S-P法检测110例胃癌组织中uPA、PAI-1的表达，根据CD34阳性的血管内皮细胞计数肿瘤组织微血管密度（MVD）。结果 （1）胃癌组织中uPA mRNA和蛋白、PAI-1 mRNA和蛋白阳性表达定位于胞质；uPA的表达随分化程度的降低有逐渐升高的趋势，PAI-1的表达随分化程度的降低有逐渐降低的趋势。（2）110例uPA mRNA及蛋白表达阳性组MVD值显著高于阴性组，差异均具有显著性（P值均＜0．05）。（3）uPA mRNA及蛋白的表达与临床分期呈正相关（P＜0．05），PAI-1的表达与临床分期和淋巴结转移无相关性。（4）uPA mRNA／蛋白与PAI-1 mRNA／蛋白的表达无相关性。结论uPA与促进胃癌的血管生成密切相关，阻断uPA的分泌和作用途径有望对胃癌浸润转移起抑制作用；胃癌组织中PAI-1可能担当重要的调节剂或者是肿瘤细胞防止自身降解的保护剂而不是这个系统的单纯抑制剂。     

Increase of a urokinase receptor-related low-molecular-weight molecule in colorectal adenocarcinomas

Proteolytic activity is important for tumor growth and metastasis. Plasminogen and urokinase-type plasminogen activator (u-PA) constitute one of the most extensively studied proteolytic systems believed to participate in these processes. u-PA cleaves plasminogen to plasmin, which in turn degrades surrounding extracellular matrix and allows tumor cells to migrate to other areas. The specific receptor for u-PA (u-PAR) has also been implicated as an essential modulator in this pathway. Eleven paired samples of colorectal cancers and normal mucosal tissues from the same patients were removed at surgery. The tissues were homogenized and the supernatants assayed for u-PAR immunoreactivity, u-PAR antigen concentration, u-PAR binding activity and u-PA activity. Immunoblot analysis showed that a major u-PAR species of 55 kDa was present in all tissues. In addition, a protein band of 4 kDa, which crossreacted with anti-u-PAR antibodies, was also found in the tumors. This protein band was either absent, or present in relatively small amounts in the normal colorectal tissues. Cross-linking experiments showed that the 55 kDa band only, and not the 41 kDa band, was able to bind either single chain urokinase-type plasminogen activator (scu-PA) or the amino terminal fragment of urokinase (ATF). The tumor samples also exhibited highly elevated u-PA activity and u-PAR antigen relative to the corresponding normal tissues. Elevated u-PA activity appeared to correlate with elevated u-PAR antigen in colorectal cancers, but not in the normal tissues. These increases were also associated with increase of the u-PAR-related, low-molecular-weight protein in the tumor samples. The measurement of u-PAR and the u-PAR-related protein, in addition to u-PA activity, could have diagnostic or prognostic value in this type of cancer.     

Plasminogen Activators and Their Inhibitor in Bone Tumors and Tumor-Like Damages

Expression of urokinase- and tissue-type plasminogen activators and their inhibitor PAI-1 in the cytosolic fraction of 20 osteosarcomas, 20 chondrosarcomas, 13 giant-cell bone tumors, 5 Ewing's sarcomas, and 7 osteochondral exostoses was studied by enzyme immunoassay. The content of urokinase-type plasminogen activator increased, while the concentration of tissue-type plasminogen activator decreased in bone tumors of various histological compositions compared to osteochondral exostoses. A positive correlation was found between PAI-1 content and the volume of osteo- and chondrosarcomas. Expression of urokinase-type plasminogen activator increased in patients with primary osteosarcomas characterized by early generalization of the pathological process.     

Pre-clinical Study of <Superscript>213</Superscript>Bi Labeled PAI2 for the Control of Micrometastatic Pancreatic Cancer

Purpose: The urokinase plasminogen activator (uPA) and its receptor (uPAR) are expressed by pancreatic cancer cells and can be targeted by the plasminogen activator inhibitor type 2 (PAI2). We have labeled PAI2 with ²¹³Bi to form the alpha conjugate (AC), and have studied its in vitro cytotoxicity and in vivo efficacy. Methods and Materials: The expression of uPA/uPAR on pancreatic cell lines, human pancreatic cancer tissues, lymph node metastases, and mouse xenografts were detected by immunohistochemistry, confocal microscopy, and flow cytometry. Cytotoxicity was assessed by the MTS and TUNEL assay. At 2 days post-cancer cell subcutaneous inoculation, mice were injected with AC by local or systemic injection. Results: uPA/uPAR is strongly expressed on pancreatic cancer cell lines and cancer tissues. The AC can target and kill cancer cells in vitro in a concentration-dependent fashion. Some 90% of TUNEL positive cells were found after incubation with 1.2 MBq/ml of AC. A single local injection of ~222 MBq/kg 2 days post-cell inoculation can completely inhibit tumor growth over 12 weeks, and an intraperitoneal injection of 111 MBq/kg causes significant tumor growth delay. Conclusions: ²¹³Bi-PAI2 can specifically target pancreatic cancer cells in vitro and inhibit tumor growth in vivo. ²¹³Bi-PAI2 may be a useful agent for the treatment of post-surgical pancreatic cancer patients with minimum residual disease.