Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0006142 (breast cancer)
 160,383 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have previously shown that thrombospondin-1 (TSP-1) and TGF-beta 1 upregulate the urokinase plasminogen activator (uPA) and its receptor (uPAR) and promote tumor cell invasion in breast cancer. To date, the effect of TSP-1 and TGF-beta 1 on the plasminogen/plasmin system in gastrointestinal epithelial malignancies has not been investigated. In this study, we determined the effect of TSP-1 and TGF-beta 1 on uPA and uPAR expression and on tumor cell invasion in pancreatic cancer. ASPC1 human pancreatic adenocarcinoma cells were incubated for 48 h on cell-conditioned media (CCM) either alone (Control) or with the addition of either TSP-1 (40 micrograms/ml) or TGF-beta 1 (5 ng/ml). uPA and uPAR expression were determined by ELISA. ASPC1 cell invasion was determined in a modified Boyden chamber type I collagen invasion assay. The upper chamber was treated with CCM either alone (Control) or with the addition of anti-uPA (10 micrograms/ml) or anti-uPAR (10 micrograms/ml). The lower chamber was treated with CCM either alone (Control) or with the addition of either TSP-1 (40 micrograms/ml) or TGF-beta 1 (5 ng/ml). TSP-1 and TGF-beta 1 induced a twofold increase on uPAR expression but only a slight increase on total uPA. Tumor cell invasion was upregulated 3.5 to 4.5-fold by TSP-1 and TGF-beta 1, respectively. Anti-uPA and anti-uPAR antibodies completely blocked the TSP-1 and TGF-beta 1-mediated pancreatic tumor cell invasion. We conclude that TSP-1 and TGF-beta 1 mediate pancreatic tumor cell invasion through upregulation of the plasminogen/plasmin system.
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PMID:The effect of thrombospondin-1 and TGF-beta 1 on pancreatic cancer cell invasion. 969 45

Potential effects of tamoxifen therapy on blood coagulation and fibrinolysis were investigated in women with breast cancer. We studied 14 parameters of hemostasis in 19 postmenopausal women receiving 20 mg tamoxifen/day as an adjuvant treatment. Blood sampling was done before and after the 1st, 3rd, and 6th month of treatment. Pretreatment values of procoagulation, anticoagulation, plasminogen, and plasminogen activator inhibitor were found within the reference range, whereas tissue-plasminogen activator, fibrin degradation products, and prothrombin-fragment 1+2 were elevated. On therapy an initial decrease of all measured parameters was observed. The effect was pronounced in coagulation inhibitors (antithrombin III, protein C and S). No pathological values (below 60%) were observed. No further effects were found during the 3rd and 6th month of treatment. Our data indicate that the decrease of hemostatic parameters during the initial phase of tamoxifen treatment is due to the timing of blood collection, which took place no more than 14 days after surgery. The reduction of coagulation inhibitors was not associated with pathological values. No cumulative effects were seen during tamoxifen therapy. The decrease was not associated with a concomittant increase of in vivo coagulation markers (prothrombin-fragment 1+2, thrombin-antithrombin-complex, fibrin degradation products). Therefore our results are likely to reflect only the resolution of postoperative activation and do not translate into a drug related thrombogenic effect.
Breast Cancer Res Treat 1998 Jul
PMID:Adjuvant antiestrogen treatment with tamoxifen in postmenopausal women with breast cancer: a longitudinal study of blood coagulation and fibrinolysis. 980 22

We have reported previously that both urokinase-type plasminogen activator (uPA) and its type 1 inhibitor (PAI-1) are statistically significant prognostic variables in patients with high-risk breast cancer (Grondahl-Hansen et al., Cancer Res., 53:2513-2521, 1993), and we recently described that the uPA receptor (uPAR) is a prognostic marker in postmenopausal, node-positive breast cancer patients (Grondahl-Hansen et al., Clin. Cancer Res., 1:1079-1087, 1995). The present retrospective study describes the prognostic impact of uPA, its receptor uPAR, and PAI-1 in breast cancer cytosol from 111 low-risk premenopausal patients and 184 low-risk postmenopausal patients with a median follow-up of 6.0 years (range, 3.8-14.9) and 7.4 (range, 3.7-14.0) years, respectively. uPA, uPAR, and PAI-1 levels were determined by sandwich enzyme-linked immunosorbent assays, and data were dichotomized using the median value as the cutoff for calculation of recurrence-free survival and overall survival. A correlation was found between the levels of each of the three molecules. In univariate analysis, high PAI-1 was significantly associated with short overall survival in postmenopausal patients [relative risk (RR), 2.3; 95% confidence interval (CI), 1.3-4.3; P = 0.005] and shorter recurrence-free survival in both premenopausal (RR, 2.5; 95% CI, 1.3-4.7; P = 0.004) and postmenopausal (RR, 1.8; 95% CI, 1.1-2.9; P = 0.02) patients. Neither uPA nor uPAR reached statistical significance in the univariate analyses. The prognostic value of uPA, uPAR, and PAI-1 was then compared with that of other established prognostic variables by multivariate analysis. PAI-1 was an independent prognostic variable for recurrence-free survival in premenopausal patients, with a RR of 2.6 (95% CI, 1.3-5.0). For recurrence-free survival (RR, 1.9; 95% CI, 1.1-3.5) and overall survival (RR, 2.6; 95% CI, 1.2-5.7) in postmenopausal patients, PAI-1 was the only independent variable left in this group of patients. Neither uPA nor uPAR reached significance in the multivariate analysis. These data, together with previously published data on the prognostic significance of components of the urokinase plasminogen activation system in breast cancer cytosols, strongly indicate that PAI-1 is a statistically significant and independent prognostic marker in both low- and high-risk breast cancer patients.
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PMID:Plasminogen activator inhibitor type 1 in cytosolic tumor extracts predicts prognosis in low-risk breast cancer patients. 981 78

Functional assembly of the plasminogen-dependent proteolytic system on the cell surface requires multiple interactions involving urokinase (uPA), urokinase receptor (uPAR), plasminogen activator inhibitors, and other molecules that mediate cell migration and adhesion. We analyzed the in vitro interaction of uPAR-containing particulate cell fractions with the amino-terminal fragment (ATF) of human urokinase and the matrix-like form of vitronectin. Binding and cross-linking of 125I-labeled ATF to crude membrane extracts from LB6-19 mouse cells overexpressing human uPARs in the presence of 25 nM urea-denatured vitronectin led to the formation of Mr 137,000, 92, 000, and 82,000 covalent complexes. Immunoprecipitation of the preformed cross-linked 125I-labeled complexes with anti-vitronectin, anti-uPA, or anti-uPAR antibodies revealed that the Mr 82,000 and 92, 000 species do contain ATF and vitronectin and identified the Mr 137, 000 species as a ternary complex formed by ATF, uPAR, and vitronectin. A similar electrophoretic pattern was displayed by acid-pretreated membranes extracted from MCF-7 breast carcinoma or HT1080 fibrosarcoma cell lines, as well as a ductal breast carcinoma specimen; the latter exhibited complex formation at concentrations of vitronectin lower than 10 nM. Finally, uPAR-vitronectin interaction was further documented by the decreased reactivity of an anti-uPAR polyclonal antibody to acid-pretreated sections of 10 breast carcinomas that had been preincubated with vitronectin. Our findings highlight the ability of uPAR to interact simultaneously with vitronectin and uPA in breast cancer, supporting a dynamic coupling of the molecular mechanisms underlying plasminogen-dependent matrix degradation and cell adhesion.
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PMID:Vitronectin binding to urokinase receptor in human breast cancer. 981 12

It is the ability to invade and metastasize that ultimately determines the prognosis in cancer. Comprising one of the key groups of molecules involved in invasion and metastasis are proteases such as urokinase plasminogen activator and cathepsins B, D, and L, as well as various metalloproteases. These proteases catalyze degradation of the interstitial matrix and basement membranes, allowing cancer cells to invade locally and metastasize to distant sites. If proteases are directly and causally involved in cancer spread, they have the potential to be new prognostic markers in cancer. One of the best examples of a correlation between high levels of a protease in a primary tumor and poor prognosis is urokinase plasminogen activation in breast cancer. In this malignancy, the urokinase plasminogen activator is a strong and independent prognostic marker and may be a marker for axillary node-negative disease. The urokinase plasminogen activator may also be a prognostic marker in other cancers such as gastric, colorectal, lung, bladder, cervical, and ovarian cancers. In a number of studies, cathepsin D has been shown to be a prognostic factor in breast cancer. However, results with cathepsin D, especially when immunocytochemistry is used for its detection, are conflicting. Levels of cathepsin B, cathepsin L, and certain metalloproteases may also supply prognostic data in certain cancers, but results with these proteases are still preliminary.
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PMID:Proteases as prognostic markers in cancer. 981 10

Tissue remodeling is a key process involved in normal development, wound healing, bone remodeling, and embryonic implantation, as well as pathological conditions such as tumor invasion and metastasis, and angiogenesis. The degradation of the extracellular matrix that is associated with those processes is mediated by a number of families of extracellular proteinases. These families include the serine proteinases, such as the plasminogen-urokinase plasminogen activator system and leukocyte elastases, the cysteine proteinases, like cathepsin D and L, and the zinc-dependent matrix metalloproteinases (MMPs) [1]. Accumulating evidence has highlighted the central role of MMP-driven extracellular matrix remodeling in mammary gland development and breast cancer.
Breast Cancer Res Treat 1998 Jul
PMID:Roles of the matrix metalloproteinases in mammary gland development and cancer. 982 15

In the medical literature there are frequently conflicting reports on the utility of biological tumour markers available in the clinical management of breast cancer. In this review we analyse current information on the relationships between the most widely investigated breast cancer biological markers including oestrogen and progesterone receptors, p53, Bcl-2, c-erbB-2, cyclin expression, proliferative activity, DNA ploidy and the urokinase plasminogen activation system, as well as their relevance to prognosis and response to clinical treatment. By biological prognostic indicator, we mean a marker that correlates with survival and disease-free survival; the term predictor marker indicates a marker that is capable of predicting tumour sensitivity or resistance to various therapies. Similarly to other authors' experiences, our analysis suggests that oestrogen receptors are weak prognostic indicators and good predictors of response to endocrine therapy. Furthermore, there are consistent data suggesting that proliferation indices are good indicators of prognosis, and that they are directly related to response to chemotherapy and closely related to response to hormonotherapy. On the contrary, there is no evidence or conflicting data for all of the other biological markers. These should be considered in the context of randomized trials in order to precisely define their prognostic and predictive roles. p53 and c-erbB-2 seem to be the most promising factors, but their use in routine practice still needs validation.
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PMID:Prognosis and prediction of response in breast cancer: the current role of the main biological markers. 985 25

The mammary gland seems to be the only organ that is not fully developed at birth. Estrogens stimulate breast tissue via estrogen receptors (ERs). In the mammary gland, ER-mediated mechanisms have been shown to regulate: various growth factors, such as TGF-alpha and TGF-beta; enzymes, such as cathepsin D and plasminogen-activator; proto-oncogenes, such as c-fos, c-myc and HER-2/neu; cyclines and other regulatory substances that provide signaling systems for cell division and differentiation; other steroid receptors and epidermal growth factor receptors. Estrogen target genes contain estrogen-responsive elements. In these genes, transcription will be activated through interaction with the estrogen/ER protein complex. Subsequent activation of proto-oncogenes provides an explanation for the stimulating effect of estrogens on the glandular breast. Progesterone may be the key in influencing the risk of breast cancer with the peak of mitotic activity in the breast during the luteal phase of the menstrual cycle. On the other hand, in human breast cancer cell lines, both proliferation and inhibition have been observed with various progestational agents. Relevant biological and clinical issues are pregnancy and exposure to exogenous hormones. The intense hormonal stimulation of pregnancy (both estrogen and progesterone) has no adverse impact on the course of breast cancer. Pregnancy, with its mammogenetic differentiation, results in the protection of this organ from carcinogenesis. Characterization of specific lobular morphology serves as an indicator of the level of differentiation achieved by the organ, and thus provides means to assess the risk of the gland undergoing neoplastic transformation when exposed to given agents. Sufficient evidence exists to indicate the possibility of a slightly increased risk of breast cancer after approximately one decade of postmenopausal estrogen use. A review of the epidemiologic studies of postmenopausal hormone replacement and the risk of breast cancer fails to provide definitive evidence. Recent information derives from observations of cellular proliferation, plasma and tissue estradiol and progesterone receptor levels, and the percentage of apoptotic epithelial cells in human breast tissue. Several studies suggest that short-term, continuous combined HRT does not increase breast cancer recurrence or mortality. The participation of sexual hormones in the mammogenetic process during pregnancy might serve as an intermediate end point in assessing the effectiveness of hormones as chemopreventive agents. Investigations based on history, and breast morphology, should enable us to select estrogens and progestogens for HRT, and adopt optimal therapeutic regimens.
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PMID:Potential benefits of estrogens and progestogens on breast cancer. 992 May 36

Cytokeratin 8 (CK8) is an intermediate filament protein that penetrates to the external surfaces of breast cancer cells and is released from cells in the form of soluble heteropolymers. CK8 binds plasminogen and tissue-type plasminogen activator (t-PA) and accelerates plasminogen activation on cancer cell surfaces. The plasminogen-binding site is located at the C-terminus of CK8. In this study, we prepared GST-fusion proteins which contained either 174 amino acids from the C-terminus of CK8 (CK8f) or 134 amino acids from the C-terminus of CK18 (CK18f). A third GST-CK fusion protein was identical to CK8fexcept that the C-terminal lysine was mutated to glutamine (CK8fK483Q). CK8f bound plasminogen; the K(D) was 0.5 microM. Binding was completely inhibited by epsilonACA. CK8fK483Q also bound plasminogen, albeit with decreased affinity (K(D) approximately 1.5 microM). CK18f did not bind plasminogen at all. All three fusion proteins bound t-PA equivalently, providing the first evidence that CK18 may function as a t-PA receptor, t-PA and plasminogen cross-competed for binding to CK8f. Thus, t-PA and plasminogen cannot bind to the same CK8f monomer simultaneously. Nevertheless, CK8f still promoted plasminogen activation, probably reflecting the fact that CK8f was purified in dimeric or tetrameric form. These studies demonstrate that CK8 may promote plasminogen activation by t-PA only when present in an oligomerized state. CK18 may participate in the oligomer, together with CK8, based on its ability to bind t-PA.
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PMID:Characterization of the binding sites for plasminogen and tissue-type plasminogen activator in cytokeratin 8 and cytokeratin 18. 998 31

The identification of patients at high risk of relapse is currently one of the most important issues in breast cancer research. However, the selection of high-risk patients continues to be difficult due to the unpredictable course of this disease. Axillary lymph node status is currently recognized as the best clinical discriminant between good and poor prognosis, yet almost 30% of node-negative patients and 65% of node-positive patients will experience a relapse. Additional prognostic markers are therefore urgently needed. Since metastatic disease is the main cause of cancer patient morbidity and mortality, the measurement of molecules functionally involved in the regulation of tumor invasion and metastasis is attractive as a means to predict prognosis. Cancer invasion is a complex process in which degradation of the extracellular matrix plays a crucial role. This degradation is accomplished by the concerted action of several proteolytic enzyme systems, including generation of plasmin by the urokinase pathway of plasminogen activation, matrix metalloproteases, and other extracellular proteases. Increased expression and secretion of urokinase plasminogen activator (uPA) strongly correlates with the malignant phenotype of many types of cells, and the central role of uPA in tumor invasion is now well established. This review will focus on the prognostic impact of components of the urokinase plasminogen activation system in breast cancer with emphasize on methodological issues.
Breast Cancer Res Treat 1998
PMID:The urokinase plasminogen activator system as a target for prognostic studies in breast cancer. 1006 75


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