Expression of extracellular matrix degrading enzymes during migration of xenografted brain cells

Proteolytic enzymes, postulated to create an avenue for cell migration by digestion of host extracellular matrix molecules, have been implicated in neoplastic glial cell migration. A similar process is likely to occur in the developing brain. Fetal rabbit brain fragments transplanted into the striatum of the neonatal Shiverer mouse give rise to cells which migrate from the graft site and differentiate into astrocytes and oligodendrocytes. Proteinase expression by transplanted brain cells was studied using immunohistochemistry and in situ hybridization. Immature donor cells expressed the mRNAs for matrix metalloproteinases (MMP) 1 (collagenase) and 3 (stromelysin). Northern blot analysis of rabbit brain showed that MMP-1 in particular is expressed in the immature rabbit cerebrum and down-regulated during maturation. Immature donor cells exhibited immunoreactivity for urokinase plasminogen activator. However, immunoreactivity was also present in maturing neurons. Donor and host astroglia in the vicinity of grafts were immunoreactive for MMP-2 and tissue-type plasminogen activator. This expression may represent a reactive phenomenon, not specifically related to cell migration, by mature astrocytes. Based upon our findings, MMP-1 appears to be a candidate for involvement in migration of immature brain cells in the cerebrum.     

晶状体上皮细胞PAI—1蛋白酶mRNA的表达

研究从转录水平确定晶状体上皮细胞是否能够合成纤麦原激活物抑制物－１蛋白酶。方法体外培养的牛晶状体上皮细胞,当细胞生长融合后,抽提ＲＮＡ;采用Ｎｏｔｈｅｒｎｂｌｏｔ分析技术,对抽提得到的牛晶状体上皮细胞ＲＮＡ用特异的ｃＤＮＡ探针进行检测。结果在牛晶状体上皮细胞的基因转录产物中存在有ＰＡＩ－１ｍＲＮＡ的表达,所表达的ＰＡＩ－１ｍＲＮＡ碱基长度为２．３ｋｂ。结论牛晶状体上皮细胞能够分泌ＰＡＩ－１蛋白酶：     

Effects of interleukin-1, tumor necrosis factor-β, and forskolin on tissue plasminogen activator activity in human osteoblastic osteosarcoma cells

Summary The effects of interleukin-1 (IL-1), forskolin, and tumor necrosis factor (TNF-) on tissue plasminogen activator (t-PA) activity were studied in the human osteoblastic osteosarcoma cell line, G292. t-PA activity was measured in the cell media using the chromogenic substrate, S-2251. After a 24 hour incubation period, IL-1 increased t-PA in a dose-dependent manner. The effect of IL-1 at 10.0 U/ml was partially inhibited in the presence of indomethacin. Forskolin (1.0 M) increased t-PA activity after 24 hours with the effects of combined treatment of IL-1 (1.0 U/ml, 10.0 U/ml) and forskolin being apparently additive in nature. TNF- (10^-8–10^-7 M) also produced increased t-PA activity in the cell medial after a 24 hour incubation period. These results suggest that the cytokines, IL-1 and TNF-, can increase t-PA activity in G292 cells and that there is both a cAMP-dependent as well as a cAMP-independent pathway involved in the regulation of this osteoblastic cell function.     

组织型纤溶酶原激活剂(t-PA)及其突变体的表达研究进展

对组织型纤溶酶原激活剂(t-PA)及其突变体在大肠杆菌、酵母、哺乳动物细胞、丝状真菌、昆虫细胞和转基因动物乳腺等表达系统中进行表达的研究工作情况进行了综述，并对各个表达系统的优缺点进行了比较。     

尿激酶型纤溶酶原激活剂系统在喉癌中的表达及意义

目的　探讨尿激酶型纤溶酶原激活剂及其抑制剂在喉癌中的表达及与临床病理各参数及预后的关系。方法　采取免疫组化链霉卵白素生物素过氧化酶法 (labeled streptoavidin biotin peroxidase,SAB)法 ,对 10 4例喉鳞状细胞癌标本中的尿激酶型纤溶酶原激活剂 (urokinase typeplasminogenactivator,uPA)、抑制剂 (plasminogenactivatorinhibitors ,PAI)PAI 1和PAI 2表达情况进行检测。结合临床随访 ,经Kaplan Meier生存曲线、log rank检验及Cox比例风险模型分析其与临床病理参数及患者生存预后的关系。结果　uPA、PAI 1、PAI 2在喉癌组织中的表达分别为 66 3 %、70 2 %、5 0 0 %。uPA、PAI 1、PAI 2的阳性表达在颈部淋巴结转移组与非转移组中差异有显著性 ,经半定量分析P值分别为 0 0 10、0 0 2 7、0 0 3 8。单因素分析显示 :淋巴结转移及复发、肿瘤细胞分化程度、uPA和PAI 2表达是影响患者预后的因素。多因素分析提示 :淋巴结转移及复发、临床分期、uPA和PAI 2是影响患者预后的独立因素。结论　uPA在喉癌转移中起着重要的作用 ;PAI 1的作用复杂 ,可能不单纯是uPA的抑制剂 ;PAI 2可能是uPA主要抑制剂 ,由于其表达不足尚不能抑制uPA的活性     

内皮素及其受体拮抗剂对纤溶系统的影响

目的 探讨内皮素1(ET-1)及其受体拮抗剂(PD142893)对纤溶系统的影响。方法培养肺静脉内皮细胞株(ECV304),分为ET-1刺激组,培养基中加ET-1至终浓度为5、10、20、50、100nmol/L;PD142893干预组,培养基中加ET-1(100nmol/L)后加入PD142893,终浓度为10、100、200、400mol/L,24小时后测定上清中的组织纤溶酶原激活物(t-PA)和纤溶酶原激活物抑制剂-1(PAI-1)的含量。结果 空白对照组PAI-1含量为78.169±1.211ng/ml,ET-1(5、10、20、50、100nmol/L)刺激组分别为66.525±1.746、68.075±1.889、66.911±0.933、67.825±3.564、67.851±2.437ng/ml,刺激组与对照组之间存在显著差异,P<0.05;而两组t-PA含量无明显差异,P>0.05。无PD142893干预的ET-1(100nmol/L)组PAI-1含量为67.951±2.437ng/ml;ET-1(100nmol/L)+PD142893(10、100、200、400nmol/L)干预组PAI-1含量分别为91.112±8.811、99.311±14.079、113.467±7.679、114.933±9.623ng/ml,两者之间存在明显差异,P<0.05;而两组间t-PA含量无明显差异,P>0.05。结论 ET-1对肺静脉内皮细胞分泌的PAI-1有显著的抑制作用,而对t-PA无显著影响;用PD142893干预后,PAI-1显著升高,t-PA的含量无明显的改变。     

Pulmonary thrombo-embolism in nephrotic syndrome treated with tissue plasminogen activator

We describe the case of a boy with steroid sensitive nephrotic syndrome and left pulmonary artery thrombo-embolism. Clinical presentation initially suggested sepsis and respiratory signs were minor. Treatment with tissue plasminogen activator infused into the pulmonary artery was successful. Conclusion Pulmonary thrombo-embolism should be considered in unwell children with nephrotic syndrome. Received: 6 September 1996 / Accepted: 17 December 1996     

乳腺癌组织和血液中组织型纤溶酶原激活剂及其抑制剂测定的临床意义

目的：了解纤维蛋白溶解系统在乳腺癌中的作用和临床意义。方法：采用发色底物法检测３０例乳腺癌组织和术前及术后血液中的ｔ－ＰＡ和ＰＡＩ－１活性，并分析其与乳腺癌各病理参数的关系。结果：术前血液中及组织中的ｔ－ＰＡ活性均与乳腺癌的各病理参数无关，而术前血液中及组织中的ＰＡＩ－１活性与腋窝淋巴结转移情况和肿瘤分期有关，且二者之间有显著正相关关系（ｒ＝０．５９１６，Ｐ＜０．０１）。术后血液中的ＰＡＩ－１活性较术前显著降低（Ｐ＜０．０１）。结论：组织中和术前血液中的ＰＡＩ－１活性测定可能有助于判断乳腺癌的腋窝淋巴结转移情况等，以决定治疗方案和选择术后化疗方案，比较术前与术后血液中的ＰＡＩ－１活性有助于判断手术效果。     

催乳素延缓hCG诱发大鼠排卵和下调纤溶酶原激活系统在卵巢中的表达

给幼龄大鼠注射10IU PMSG,48h后注射7IU hCG,或者hCG加不同剂量的催乳素(PRL).在不同时间取出卵巢,检查输卵管中卵子数和卵巢不同细胞中组织型纤溶酶原激活因子(tPA)和抑制因子(PAI-1)mRNA含量和活性.结果表明:PRL减少hCG诱发的排卵数并有明显剂量和时间抑制曲线.当hCG注射24h后,在两组动物输卵管的卵子数无明显差异.PRL同时抑制hCG所诱发的颗粒细胞tPA表达;与少匕相反PRL还能显著刺激膜一间质细胞PAI-1mRNA表达.上述实验结果表明,PRL只暂时延缓而不是完全抑制hCG诱发的大鼠排卵.上述作用可能是通过抑制纤溶酶激活系统在卵巢中的表达引起的.