Prognostic impact of urokinase-type plasminogen activator (uPA) and its inhibitor (PAI-1) in cytosols and pellet extracts derived from 892 breast cancer patients

Abstract

SummaryTo evaluate the clinical relevance of urokinase-type plasminogen activator (uPA) and its type-1 inhibitor (PAI-1) measured by a recently developed enzyme-linked immunosorbent assay (ELISA), we analysed both components in samples derived from 892 patients with primary breast cancer (median follow-up 99 months). The assays were performed in cytosolic extracts as well as in corresponding detergent extracts of pellets obtained after ultracentrifugation, which was carried out when preparing the cytosolic fractions for routine steroid hormone receptor determination. Statistically significant correlations were found between the cytosolic levels and those determined in the pellet extracts (Spearman correlation coefficient r s = 0.60, P < 0.0001 for uPA and r s = 0.65, P < 0.0001 for PAI-1). Furthermore, strong correlations were found between the levels of both uPA (r s = 0.85, P < 0.0001) and PAI-1 (r s = 0.90, P < 0.0001) in the cytosols and their levels previously measured with ELISAs based on commercial reagents. In both Cox univariate and multivariate analysis, high cytosolic levels of uPA or PAI-1 were significantly associated with increased rates of relapse and death. The levels of uPA and PAI-1 in the pellet extracts also provided prognostic information, although to a lesser extent compared with the cytosolic extracts. The prediction of prognosis on the basis of uPA and PAI-1 assessed by an alternative ELISA once again emphasizes the established prognostic role and usefulness of these parameters in selection of breast cancer patients at high or low risk of recurrence.Keywords: urokinase-type plasminogen activator; plasminogen activator inhibitor; enzyme-linked immunosorbent assay; cytosol; breast cancer; prognostic impact 1190British Journal of Cancer (1999) 79(7/8), 1190-1198 © 1999 Cancer Research Campaign Article no. bjoc.1998 Received of uPA and PAI-1 were correlated to those obtained earlier with ELISAs based on commercial reagents. MATERIALS AND METHODS Patients and tumour characteristicsIn the present study, 892 patients with primary operable breast cancer (modified mastectomy, 446 patients; breast-conserving lumpectomy, 446 patients) were included. Inclusion criteria for patients from whom tumour biopsies or cytosol samples were stored in the tumour bank of the Rotterdam Cancer Centre (Dr Daniel den Hoed Kliniek) were: (i) primary diagnosis of breast cancer between 1979 and 1989; (ii) no signs of distant metastasis at diagnosis; (iii) no previous diagnosis of carcinoma, with the exception of basal cell skin cancer and cervical cancer stage Ia; (iv) no evidence of disease within 1 month after primary surgery. In cases of mastectomy after an initial lumpectomy for residual disease, the mastectomy is considered as (part of) primary treatment. The median number of lymph nodes removed surgically was 11. Patients without primary surgery or patients who received neoadjuvant treatment before primary surgery were excluded. Median age of the patients at the time of surgery was 56 years (range 25Ð89 years)....

Prognostic impact of urokinase-type plasminogen activator receptor (uPAR) in cytosols and pellet extracts derived from primary breast tumours

“…Evidently, this finding is a (de Witte et al, 1999a), and for tPA, 2.40 and 13.01 ng mg protein -1 (de Witte et al, 1999b). These biochemical assays are very sensitive and easily can be performed on as little as 25 mg of tissue.…”

“…The combined prognostic value of the cytosolic levels of uPAR and of uPA, the latter previously determined in the same samples (De Witte et al, 1999a), with respect to RFS and OS is visualized in Figure 3. Patients with high levels of uPAR (i.e.…”

Prognostic value of tissue-type plasminogen activator (tPA) and its complex with the type-1 inhibitor (PAI-1) in breast cancer

“…Recently, the antigen levels of PAI-1 were determined in the same cytosols and pellet extracts, applying the same ELISA framework (De Witte et al, 1998). The (total) levels of PAI-1 and tPA in both types of extracts were very weakly negatively correlated with each other (r s = -0.073, P = 0.033, for cytosols; r s = -0.12, P = 0.001, for pellet extracts).…”

“…The patients, whose samples were stored in the tumour bank of the Rotterdam Cancer Institute (Dr Daniel den Hoed Kliniek), included those for which tumour levels of uPA and PAI-1 were determined previously (De Witte et al, 1998). Patients with primary diagnosis of breast cancer between 1979 and 1989, without evidence of distant metastasis at the time of diagnosis, were included in the study.…”

Dedifferentiation of serous ovarian cancer from cystic to solid tumors is associated with increased expression of mRNA for urokinase plasminogen activator (uPA), its receptor (uPAR) and its inhibitor (PAI-1)

“…4,5 Also, high tumor tissue concentrations of these factors are associated with shorter survival for patients with several different types of malignant tumors. [5][6][7][8] Increased levels of uPAR in plasma are related to poor prognosis in colon cancer. 9 Supporting results have been obtained in studies of corresponding mRNA species.…”