Prognostic value of urokinase plasminogen activator in primary breast carcinoma: comparison of two immunoassay methods

Abstract

Summary Urokinase-type plasminogen activator (uPA) is a potentially important prognostic factor in breast cancer for identifying patients at high risk of recurrence. This retrospective study assessed two enzyme-linked immunosorbent assay (ELISA) methods measuring uPA antigen levels in 499 primary breast cancer cytosols. Both uPA methods were applied to cytosols used routinely for oestrogen (ER) and progesterone (PgR) receptor assays. uPA was determined using a classical ELISA method (Imubind; American Diagnostica) and a novel automatic immunoluminometric assay (Lia; Sangtec Medical). The uPA Imubind method revealed about twice as much uPA antigen (median 0.75 ng mg-1 protein) as the uPA Lia method (median 0.38 ng mg-1 protein). The correlation coefficient between the two methods was acceptable (r = 0.81), but the two techniques are not interchangeable. Univariate analyses confirmed the poor outcome of patients whose tumours contained large amounts of uPA, regardless of the technique used. Multivariate analyses showed that uPA Imubind and uPA Lia values were both strong independent prognostic factors.Keywords: urokinase plasminogen activator; luminometric immunoassay; prognosis; breast cancer Evidence has accumulated that invasion and metastasis by solid tumours require the action of tumour-associated proteases, which promote the dissolution of the surrounding tumour matrix and basement membranes. In several independent studies of a variety of cancer types, i.e. breast (Dano et al, 1985;Duffy et al, 1988), colorectal (Ganesh et al, 1994;Skelly et al, 1995), lung (Oka et al, 1991), ovary (Kuhn et al, 1994), gastric (Nekarda et al, 1994;Cho et al, 1997) and bladder cancer (Hasui et al, 1992), high levels of the serine protease urokinase-type plasminogen activator (uPA) antigen in tumour extracts were associated with rapid disease progression and poor prognosis. In this study of 499 primary breast cancer tumours, we used two different assay methods for uPA antigen, in order to compare an enzyme-linked immunoassay (uPA Imubind; American Diagnostica) with a new automatic immunoluminometric assay (uPA Lia; Sangtec Medical), to assess the relationships between uPA values and clinical and histological factors and to evaluate the prognostic value of the two methods in multivariate analyses. MATERIALS AND METHODS PatientsThe study group consisted of 499 breast cancer patients treated at the Centre Rene Huguenin (CRH) between 1981 and 1989. The median age was 58 years (range 24-84 years). Patients were selected according to the following criteria: (1) primary, unilateral breast tumour; (2) full follow-up at CRH; (3) previously untreated, Correspondence to: C Bouchet without evidence of metastatic disease or any other malignant tumour at the time of diagnosis; (4) surgery as the first treatment; and (5) complete clinical, histological and biological information, especially concerning hormone receptors and antigen levels of uPA measured in cytosols by the two methods. All tumours were graded by a method based on the criteri...

Prognostic value of uPA and p53 accumulation measured by quantitative biochemical assays in 1245 primary breast cancer patients: a multicentre study

“…We confirm the negative correlation between uPA levels and ER status, and the positive correlations between uPA levels, histological grade and tumour size (Duffy, 1996). In our study, the prognostic value of uPA was comparable to that of lymph node involvement, and a high uPA level was still an independent prognostic indicator in multivariate analysis, confirming previous studies based on ELISA methods (Foekens et al, 1992;Jänicke et al, 1993;Duffy, 1996;Bouchet et al, 1998) or LIA (Fernö et al, 1996;Bouchet et al, 1998;Peyrat et al, 1998).…”

“…In this study we used hormone receptor buffer, which yields lower uPA values than Triton X-100 buffer (Janicke et al, 1994a;Knoop et al, 1998). However, significant prognostic value has also been observed with cytosols prepared for hormone receptor assays (Foekens et al, 1992;Bouchet et al, 1994Bouchet et al, , 1998Jänicke et al, 1994a;Fernö et al, 1996;Peyrat et al, 1998). Our technique has the advantage of being automated.…”

“…Our technique has the advantage of being automated. Bouchet (1998) recently showed a good concordance between the results of the most widely used enzyme-linked immunosorbent assay (ELISA) test for uPA (American Diagnostica) and the LIA assay, although the two methods were not interchangeable: indeed, lower uPA levels were obtained with luminometry on cytosols prepared for hormone receptor assays. If we compare our results to those of studies using the same assay (Fernö et al, 1996;Peyrat et al, 1998), median uPA values were close (Table 7).…”

“…Patients were followed for a median of 75 months. Measurements were made using an automatic quantitative biochemical method (Borg et al, 1995;De Witte et al, 1996;Fernö et al, 1996;Berns et al, 1997;Bouchet et al, 1998;Peyrat et al, 1998), which is feasible for routine determination on cytosols prepared for hormone receptor assays.…”

Regulation of hepatocyte growth factor-mediated urokinase plasminogen activator secretion by MEK/ERK activation in human stomach cancer cell lines

“…The over-expression of uPA has been detected in various malignancies including breast (Miyake et al, 1999), prostate (Yang et al, 2000), colon (Duggan et al, 1995), and pancreatic (Lee et al, 2003b). Some data have shown that a high level of uPA in tumors is associated with a rapid disease progression and a poor prognosis (Solomayer et al, 1997;Bouchetm et al, 1998). In addition, studies performed with both in vitro and in vivo experimental models have demonstrates that the levels of uPA are closely associated with the degree of tumor cell invasion (Xing et al, 1996).…”