Benraad T J, Geurts-Moespot J, Grøndahl-Hansen J, Schmitt M, Heuvel J J, de Witte J H, Foekens J A, Leake R E, Brünner N, Sweep C G
532 Department of Experimental and Chemical Endocrinology, University of Nijmegen, Netherlands.
Eur J Cancer. 1996 Jul;32A(8):1371-81. doi: 10.1016/0959-8049(96)00118-9.
The urokinase-type plasminogen activator (uPA) is considered to play a key role in the process of invasion and metastasis. In several independent studies, in a variety of cancer types (e.g. of the breast, colon, stomach, lung, ovary), high antigen levels of uPA in tumour extracts have been associated with rapid disease progression. In these studies, different sets of antibodies and standards (often as commercially available uPA ELISA kits) have been used. The standards provided with the different uPA ELISA kits are different from each other in both composition and source. In addition, the different uPA ELISA kits use antibodies which differ in specificity and affinity for the various forms of uPA including pro-uPA, HMW-uPA, LMW-uPA, the aminoterminal fragment (ATF) and complexes with inhibitors (PAI-1 and PAI-2) and the receptor (uPAR). Further, the composition of tumour tissue extraction buffers differ significantly among the published studies. Thus, it is not surprising that the ranges of cytosolic uPA levels reported differ considerably even when measured within the same tumour type. These discrepancies led the EORTC Receptor and Biomarker Study Group, in conjunction with the BIOMED-1 consortium on 'Clinical Relevance of Proteases in Tumour Invasion and Metastasis', to organise a workshop to study the characteristics associated with six different uPA immunoassays (ELISA) used in clinical studies reported in the literature. Although the absolute uPA antigen values measured with the respective uPA ELISA kits differed, high correlations were obtained for any two of the four uPA ELISA kits finally applied to sets of breast cancer cytosol preparations. The preparations used at present as standards in the various uPA ELISA kits are not representative of actual human breast cancer cytosols. Thus absolute standardisation is only possible by using a common reference sample (breast cancer cytosol) and similarly composed ELISA uPA kits. Then it will be possible to generate comparable data on clinical tissue as well as to check for batch-to-batch variations within particular ELISA kits.
尿激酶型纤溶酶原激活剂（uPA）被认为在侵袭和转移过程中起关键作用。在几项独立研究中，在多种癌症类型（如乳腺癌、结肠癌、胃癌、肺癌、卵巢癌）中，肿瘤提取物中uPA的高抗原水平与疾病快速进展相关。在这些研究中，使用了不同的抗体组和标准品（通常为市售的uPA ELISA试剂盒）。不同uPA ELISA试剂盒提供的标准品在组成和来源上均互不相同。此外，不同的uPA ELISA试剂盒使用的抗体对各种形式的uPA（包括pro-uPA、HMW-uPA、LMW-uPA、氨基末端片段（ATF）以及与抑制剂（PAI-1和PAI-2）和受体（uPAR）的复合物）的特异性和亲和力也不同。此外，已发表的研究中肿瘤组织提取缓冲液的组成差异很大。因此，即使在同一肿瘤类型中进行测量，所报道的胞质uPA水平范围存在相当大的差异也就不足为奇了。这些差异促使欧洲癌症研究与治疗组织（EORTC）受体和生物标志物研究小组与“蛋白酶在肿瘤侵袭和转移中的临床相关性”的BIOMED-1联盟联合组织了一次研讨会，以研究文献报道的临床研究中使用的六种不同uPA免疫测定法（ELISA）的相关特性。尽管使用各自的uPA ELISA试剂盒测得的绝对uPA抗原值不同，但最终应用于乳腺癌细胞溶质制剂组的四种uPA ELISA试剂盒中的任意两种之间都获得了高度相关性。目前在各种uPA ELISA试剂盒中用作标准品的制剂并不代表实际的人乳腺癌细胞溶质。因此，只有通过使用共同的参考样品（乳腺癌细胞溶质）和组成相似的ELISA uPA试剂盒，才有可能实现绝对标准化。这样就有可能生成关于临床组织的可比数据，并检查特定ELISA试剂盒内的批次间差异。
