Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P00750 (PLA)
 16,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The distributions of urokinase and tissue plasminogen activators (uPA, tPA), uPA receptor (uPAR), and plasminogen activator inhibitors (PAI-1, PAI-2) were studied immunohistochemically in two subsets of colorectal adenocarcinomas with low and high aggressiveness, respectively: nine Dukes' stage A tumors with additional other good prognostic markers and 13 Duke's stage C tumors with also other poor prognostic markers (referred to as Dukes' stage A and Dukes' stage C tumors). The results showed that these components of the tissue destructive plasminogen activation system were accumulated at the invading front of the tumors. Both tumor groups showed accumulations of uPA, uPAR, and PAI-1 at the tumor-host interface compared with the location within the tumor epithelium and the adjacent normal mucosa and muscularis propria (all P < .05). However, the uPA level at the tumor-host interface in the Dukes' stage C tumors was twice the level in the Dukes' stage A tumors (P < .05). The uPAR level was also significantly higher in the Dukes' stage C tumors (P < .05), whereas the PAI-1 level was not significantly higher. This may indicate that uPA in more aggressive tumors exceeds the inhibitory capacity represented by PAIs, resulting in enhanced tissue destructive potential that promotes tumor invasion. uPA and uPAR antigen levels and the uPA/PAI-1 ratio at the tumor-host interface appeared to be related to tumor aggressiveness in colorectal cancer.
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PMID:Antigen levels of urokinase plasminogen activator and its receptor at the tumor-host interface of colorectal adenocarcinomas are related to tumor aggressiveness. 755 47

Human colorectal carcinogenesis has been shown previously to be associated with impressive changes in the tissue levels of plasminogen activators and their inhibitors, exemplified by an increase in the urokinase-type plasminogen activator (u-PA) and the inhibitors PAI-1 and PAI-2, and a decrease in tissue-type plasminogen activator (t-PA). In the present study we evaluated the prognostic significance of these parameters to the overall survival of patients with colorectal cancer, in conjunction with several major clinicopathological parameters like age, gender, differentiation grade, and Dukes' stage. Univariate analyses revealed that a low t-PA antigen level, low t-PA activity, and high u-PA/t-PA antigen ratio in normal mucosa and a high u-PA and PAI-2 antigen level in carcinomas are prognostic for a poor overall survival of patients with colorectal cancer. The prognostic value of t-PA antigen and activity in normal mucosa, the antigen ratio of u-PA in carcinoma (C) and t-PA in corresponding normal (N) mucosa [u-PA(C)/t-PA(N) antigen ratio], and PAI-2 antigen in carcinomas was found to be independent from clinicopathological parameters by multivariate analyses. These observations illustrate the clinical importance of the plasminogen activation cascade at the tissue level in colorectal cancer invasion, metastasis, and survival.
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PMID:Prognostic relevance of plasminogen activators and their inhibitors in colorectal cancer. 803 38

In patients with colorectal cancer, profound alterations of the plasminogen activator system have been described at the tumor level, but conflicting results have been obtained for fibrinolytic parameters in plasma. Components of the fibrinolytic system, including tissue-type and urokinase-type plasminogen activators and their inhibitors type 1 and 2, were measured in tissue and/or plasma from 41 patients with colorectal cancer and in 40 controls. Procoagulant activity of freshly isolated mononuclear cells (basal activity) and the procoagulant activity and fibrinolytic proteins produced by the cells after incubation for 18 h without exogenous stimulation were also evaluated. Malignant tissue extracts had significantly higher levels of urokinase-type plasminogen activator and plasminogen activator inhibitor-1, but lower levels of tissue-type plasminogen activator than normal mucosa. Plasminogen activator inhibitor-1 alone was higher in advanced (Dukes' stages C + D) than limited (B) tumors. Plasminogen activator inhibitor-2 was not different in malignant tissue and normal mucosa. Plasma levels of plasminogen activator inhibitor-1 antigen were significantly increased in cancer patients compared with controls, but there were no differences in tissue-type and urokinase-type plasminogen activator, in plasminogen activator inhibitor-2, and D-dimer levels. Intra-patient analysis revealed no significant correlation between tumor and plasma levels of plasminogen activators or type 1 inhibitor. Tissue-type plasminogen activator, but not the urokinase type or inhibitor type 1, was higher in venous than in arterial blood collected at the tumor site during surgery. Basal procoagulant activity of mononuclear cells and the procoagulant activity and inhibitor type-2 produced by the cells after short-term culture were comparable in patients and controls. These findings indicate that, at least in our patients with colorectal cancer, the profound changes occurring at tumor level are barely detectable in the blood. Thus, the clinical relevance of plasma fibrinolytic parameters, especially urokinase-type plasminogen activator antigen, as tumor markers in colorectal cancer remains to be established.
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PMID:Blood and tissue fibrinolytic profiles in patients with colorectal carcinoma. 878 47

Despite the advances in pre-, peri- and post-operative medical care of colorectal carcinoma patients, the prognosis has improved only marginally over recent decades. Thus, additional prognostic indicators would be of great clinical value to select patients for adjuvant therapy. In previous studies we found that colorectal carcinomas have a marked increase of the urokinase-type of plasminogen activator (u-PA), and the inhibitors PAI-1 and PAI-2, whereas the tissue-type plasminogen activator (t-PA) is found to be decreased in comparison with adjacent normal mucosa. In the present study we evaluated the prognostic value of several plasminogen activation parameters, determined in both normal and carcinomatous tissue from colorectal resection specimens, for overall survival of 136 Dukes' stage B and C colorectal cancer patients, in relation to major clinicopathological parameters. Uni- and multivariate analyses indicated that a high PAI-2 antigen level in carcinoma, a low t-PA activity and antigen level and a high u-PA/t-PA antigen ratio in adjacent normal mucosa are significantly associated with a poor overall survival. A high ratio of u-PA antigen in the carcinomas and t-PA antigen in normal mucosa, i.e. u-PA(C)/t-PA(N), was found to be predictive of a poor overall survival as well. All these parameters were found to be prognostically independent of the clinicopathological parameters. Multivariate analysis of combinations of these prognostically significant plasminogen activation parameters revealed that they are important independent prognostic indicators and have in fact a better prognostic value than their separate components. Based on these combined parameters, subgroups of patients with Dukes' stage B and C colorectal cancer could be identified as having either a high or a low risk regarding overall survival. In conclusion, these findings emphasize the relevance of the intestinal plasminogen activation system for survival prognosis of patients with colorectal cancer and, in the future, might constitute a patient selection criterion for adjuvant therapy.
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PMID:Contribution of plasminogen activators and their inhibitors to the survival prognosis of patients with Dukes' stage B and C colorectal cancer. 919 84

Urokinase type plasminogen activator (u-PA) secreted by cancer cells is considered to play a key role in promoting invasion and metastasis of cancer cells. This study was designed to evaluate the expression and prognostic value of u-PA in Dukes B and C colorectal cancer. u-PA expression was investigated in 57 Dukes B or C colorectal cancers using a monoclonal antibody against u-PA. u-PA expression was mainly observed on the cytoplasm of cancer cells, and was associated with relapse, especially hematogenous metastasis (p=0.025, the chi2 test). Patients with high u-PA expression had a lower rate of DFS (9/22 events) compared to those with low u-PA expression (6/35 events) (p=0.061, log-rank test). This study demonstrated that u-PA expression might be a novel prognostic factor in Dukes B and C colorectal cancer.
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PMID:The expression of urokinase type plasminogen activator is a novel prognostic factor in dukes B and C colorectal cancer. 946 74

Cysteine proteases [Cathepsin B and L (CATB, CATL)] and the serine protease urokinase type plasminogen activator (UPA) with its inhibitor type-1 (PAI-1) are thought to play an important part in colorectal cancer invasion and metastasis. To our knowledge, however, cathepsins and plasminogen activator/inhibitor system have not been evaluated in the same study. The authors using the ELISA method, determined the protease antigen concentrations in colorectal cancer tissue and in normal tissue distant from tumour, in 35 patients with colorectal cancer. They also evaluated the relationship that these proteases may have with the major histomorphological parameters and tumour staging. Significantly higher antigen levels were found: 1. in cancerous tissue vs. tumour free tissue (CATB, CATL, UPA, PAI-1); in colorectal cancer with vs. without metastasis (CATB, CATL, UPA, PAI-1); 3. in poorly vs. well differentiated tumours (CATB, UPA, PAI-1); 4. in advanced Dukes' stages (CATB, UPA, PAI-1). The simultaneous activation of cathepsins and plasminogen activator/inhibitor system in colorectal cancer confirms their role in colorectal tumor biology and particularly in the process of invasion and metastasis. Our results suggest the possible prognostic impact of these proteases in colorectal cancer.
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PMID:[The role of cathepsins and the plasminogen activator/inhibitor system in colorectal cancer]. 1048 82

The aim of this study was to evaluate the cytosolic tissue-type plasminogen activator (tPA) content in colorectal cancer, its possible relationship with the clinicopathologic parameters of tumors, and its prognostic significance. We have therefore examined by immunoenzymatic assay the cytosolic tPA content in tumors and paired surrounding normal mucosa samples from 162 colorectal cancer patients. Cytosolic tPA levels were significantly higher in surrounding normal mucosa samples than in neoplastic tissues (4.01 +/- 5.07 vs 2.63 +/- 5.82 ng/mg protein; p < 0.0001). By contrast, no significant correlation was found between tPA content and clinicopathologic tumor parameters such as location, Dukes' stage, histologic grade, and DNA content or S-phase fraction. However, the results indicated that a high cytosolic tPA content (> 0.75 ng/mg protein) in tumors predicted for a shorter relapse-free and overall survival (both p < 0.05) in 123 resectable colorectal cancer patients who were prospectively evaluated during a mean follow-up period of 32.2 months. This suggests that tPA may give additional information to that provided by other biochemical markers currently used in colorectal cancer.
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PMID:Tissue-type plasminogen activator (tPA) content in colorectal cancer and in surrounding mucosa: relationship with clinicopathologic parameters and prognostic significance. 1076 40

Colorectal cancer is one of the most common tumour types with approximately one third of the tumours located within the rectum. Rectal cancer differs somewhat from colon cancer, e.g. regarding the method of operation and the use of preoperative radiotherapy due to a tendency for local tumour recurrence. Proteolytic enzymes have been identified as key molecules in tumour invasion and metastasis, and factors within the urokinase-plasminogen activation (uPA) system have been associated with prognosis in several tumour types, including colorectal cancer. Recently, methods have been developed to analyse the soluble fraction of the plasminogen activator receptor (suPAR) in blood samples. An association between elevated suPAR levels and poor prognosis has recently been demonstrated in colorectal cancer. We have measured suPAR levels in pretreatment plasma samples from 173 rectal cancer patients in order to confirm its prognostic strength in this clinical entity. suPAR levels were determined in ethylenediamine tetraacetic acid (EDTA) plasma by a kinetic enzyme-linked immunosorbent assay (ELISA) and analysed with respect to sex, age, Dukes' stage, tumour differentiation grade and survival. In a univariate analysis, continuous suPAR plasma levels were associated with survival (P<0.001) with shorter survival among patients with high suPAR values. Patients with suPAR values within the upper quartile had significantly shorter survival (hazard ratio (HR) 2.2, 95% confidence interval (CI) 1.3-43.7, P=0.002). In a multivariate Cox analysis, increasing suPAR values predicted shorter survival independent from Dukes' stage and tumour differentiation grade with an adjusted HR of 2.2 per ng/ml suPAR (95% CI 1.2-4.0, P=0.01). This study thus confirms that measurement of suPAR in preoperative plasma samples gives independent prognostic information in rectal cancer patients, higher values being associated with shorter survival.
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PMID:Prognostic importance of the soluble plasminogen activator receptor, suPAR, in plasma from rectal cancer patients. 1126 58

The aim of this study was to determine the expression of proteinases and inhibitors from the matrix metalloproteinase (MMP) (MMPs 1, 2, 3, 9, tissue inhibitors of metalloproteinases (TIMPs) 1, 2) and plasminogen activator ((PA) urokinase (uPA), tissue type (tPA), uPAR, plasminogen activator inhibitors (PAIs) 1, 2) systems in colorectal cancer pathology by gelatin zymography, enzyme-linked immunosorbent assays (ELISAs) and quenched fluorescent substrate hydrolysis. The levels of all studied MMPs, uPA, uPAR, TIMP-1 and PAIs were significantly greater in tumour tissues than normal tissues. However, tPA and TIMP-2 were greater in normal colon (P<0.05, Mann-Whitney) e.g. PAI-1: tumour, median 14.9 (range 0.2-80.2) ng/mg total protein; normal, 2.1 (0.1-65.0). Tumour levels of several factors, in particular MMP-1 and PAI-1, correlated with pathology, i.e. Dukes' stage, differentiation, lymphatic or vascular invasion and tumour depth. The interactions between proteinase systems in colorectal cancer are complex and the balance between active proteinases and their inhibitors is important for extracellular matrix (ECM) degradation/remodelling at each stage of the metastatic cascade.
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PMID:The plasminogen activator and matrix metalloproteinase systems in colorectal cancer: relationship to tumour pathology. 1270 68

The lipid mediator platelet-activating factor (PAF) plays a role in cancer. We investigated its presence in human colon carcinoma by assessing the levels of tissue phospholipase A(2) (PLA(2), the key enzyme in the generation of the lyso-PAF precursor), lyso-PAF, PAF and acetylhydrolase activity (AHA, the key enzyme in PAF degradation) in colorectal cancer patients and by correlating them with Dukes' classification. The results highlighted that the tumour tissues of Dukes' A and B patients had significantly higher PLA(2), lyso-PAF, PAF and AHA levels as compared with nontumour tissues. Dukes' C patients had higher PLA(2), lyso-PAF and AHA levels but unchanged PAF. Dukes' D patients had higher AHA levels but unchanged PLA(2), lyso-PAF and PAF. A pathophysiological role for PAF is suggested in human colon carcinoma.
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PMID:Tissue concentrations of platelet-activating factor in colorectal carcinoma: inverse relationships with Dukes' stage of patients. 1456 51


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