Tissue-type plasminogen activator (tPA) in breast cancer: relationship with clinicopathological parameters and prognostic significance.
ABSTRACT Tissue-type plasminogen activator (tPA) is a serine protease primarily involved in the intravascular dissolution of blood clots. High intratumoral tPA levels are associated with prognosis in several human tumors. In addition, tPA has been shown to be an estrogen-inducible protein in human breast cancer cell lines. The aim of the present study was to analyze the cytosolic tPA content in primary breast carcinomas and its potential clinical value.
tPA was measured by a solid-phase enzyme immunoassay in tumor cytosol samples obtained from 800 patients with breast cancer. The median follow-up period was of 49.2 months.
Cytosolic tPA levels ranged widely in breast carcinomas (median: 3.9; range: 0.1- 315.3 ng/mg protein). tPA levels were significantly lower in large tumors, as well as in those showing poor differentiation, estrogen (ER) or PgR-negativity, aneuploidy, or a high S-phase fraction. In addition, low tPA intratumoral levels were associated with a high probability of both shortened relapse-free and overall survival in all patients and in the subgroup with node-negative tumors. However, our results did not show any significant relationship between intratumoral tPA levels and prognosis in the different subgroups of patients, stratified according to the type of systemic adjuvant therapy received (chemotherapy, tamoxifen or chemotherapy plus sequential tamoxifen).
The results of the present investigation indicate that low intratumoral tPA levels are associated with aggressiveness and poor prognosis in breast cancer patients. However, the study suggests that tPA levels do not predict response to systemic adjuvant therapy.
- Seminars in Thrombosis and Hemostasis 08/1991; 17(3):303-12. · 4.22 Impact Factor
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ABSTRACT: In 1977 the National Surgical Adjuvant Breast and Bowel Project initiated a prospectively randomized clinical trial for women with primary operable breast cancer and positive axillary nodes. In this study 1891 patients were randomized to receive L-phenylalanine mustard and 5-fluorouracil (PF) either with or without tamoxifen (T). In this interim report findings are presented concerning disease-free survival (DFS) and survival as related to age and to estrogen receptor (ER) and/or progesterone receptor (PR) content of the tumor. The median follow-up time is 3 yr. Patients 50 yr of age or older with either 1-3 or more than 3 positive axillary nodes had a markedly longer disease-free survival on PFT than did those receiving PF adjuvant therapy (p less than 0.001). The effectiveness of PFT was related to the levels of tumor receptors. Patients 50 yr old or more with both tumor ER and PR levels of 10 fmole or more ("high") displayed the greatest benefit in disease-free survival from PFT (p = 0.004). Analyses by age indicated that it is more appropriate to divide patients of 50 yr or older into two age groups, 50-59 and 60-70 yr old. In the former the survival results were poorer on PFT when tumor PR was low, whereas, regardless of receptor levels, those 60-70 yr old experienced an advantage on PFT. In women under 50 yr of age, there was no difference in disease-free survival (p = 0.64), but survival results favored the PF over the PFT treated (p = 0.06). Patients under 50 yr with tumor ER and PR levels under 10 fmole ("low") had a poorer survival when given PFT (p = 0.003). Those whose tumors demonstrated a high ER and a low PR also had a shorter survival on PFT (p = 0.01). The observation of no benefit in younger patients when both receptor levels were high, but a benefit in older patients with receptor-poor tumors, indicates that, at least according to the conditions of this study, the difference between the two age groups cannot be explained by the association of age with receptor content. Multivariate analyses considered the effects of the number of positive nodes, age, ER, and PR. They support the conclusion that, while nodes and ER exert strong prognostic influences in both PF- and PFT-treated patients, the PR content of tumors is a stronger predictor of the effectiveness of PFT therapy than is ER content.(ABSTRACT TRUNCATED AT 400 WORDS)Journal of Clinical Oncology 05/1983; 1(4):227-41. · 18.04 Impact Factor
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ABSTRACT: Neoplastic growth and metastatic spread of adenocarcinomas is characterized by a marked increase of urokinase-type plasminogen activator (u-PA) and a decrease of tissue-type plasminogen activator (t-PA). In this study, the authors determined the activity and antigen levels of u-PA and t-PA, and their inhibitors, plasminogen-activator inhibitors types 1 and 2 (PAI-1 and PAI-2), in normal mucosa, adenomatous polyps, and adenocarcinomas of the human colon. The decrease in t-PA activity in the neoplastic tissues, determined enzymatically and zymographically, was significantly correlated with an increase in PAI-1 and PAI-2, in particular in carcinomas. In spite of significantly higher inhibitor levels in the neoplastic tissues, u-PA was found to be increased as well, both in antigen level and in activity. The authors conclude that PAI-1 and PAI-2 are significantly increased in neoplastic tissue of the human colon and contribute considerably to the decrease of t-PA activity in carcinomas. However, the malignancy-associated increase in u-PA seems not to be affected by the plasminogen activator inhibitors. Thus, it appears that there is an imbalance between plasminogen activators and their inhibitors in colonic neoplasia in favor of u-PA, which may contribute to plasmin-mediated growth, invasiveness, and metastasis. This feature was also noticed in adenomatous polyps, supporting the malignant potency of adenomas.Gastroenterology 01/1992; 101(6):1522-8. · 12.82 Impact Factor