Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.7 (plasmin)
 9,023 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Acid stable trypsin inhibitor having the same antigenicity as urinary trypsin inhibitor was first identified in the bile of patients with malignant tumors (biliary tract carcinoma or pancreas head carcinoma) and gallstones. Bile trypsin inhibitor from malignant tumor patients was partially purified by DEAE cellulose ion exchange column chromatography. Two molecular forms of the inhibitor were identified. The main form had a molecular weight of about 86,000 and the minor one a molecular weight of 31,000 as determined by gel filtration. Using isoelectric focussing, the larger molecular form gave a pI value of 2.0 and the smaller form, a pI value of 5.1. The isolated larger form migrated on the slightly cationic side of human serum albumin by analytical polyacrylamide gel electrophoresis. The larger form reacted and fused with anti-urinary trypsin inhibitor serum and strongly inhibited trypsin, partially inhibited chymotrypsin and plasmin, but did not inhibit urokinase. The clinical significance of acid stable trypsin inhibitor is discussed.
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PMID:Acid stable trypsin inhibitor in bile. 374 18

Discrepancies in correlations between fibrinolytic activity and metastatic potential of malignant cells has resulted in speculation on the putative role of plasminogen activators (PA) in cancer. In this report we have compared lymphocyte PA from 40 patients with chronic lymphocytic leukemia (CLL) to normal human B- and T-lymphocytes. Lymphocytes were isolated from peripheral blood by Ficoll-Hypaque centrifugation. The B- and T-cells were further separated on nylon wool columns. Cell PA activity and cell membrane PA were determined using 3H-fibrin-coated plates with added human plasminogen. Lymphocytes did not lyse 3H-fibrin in the absence of plasminogen. Plasminogen-dependent fibrinolytic activities of normal B- and T-lymphocytes were comparable. The addition of protease inhibitors with trypsin or plasmin specificity to lymphocytes significantly inhibited normal PA, thus substantiating the serine protease spectrum of lymphocyte PA. Examination of lymphocytes from greater than 95% of patients with chronic lymphocytic leukemia revealed a marked decrease in lymphocyte and cell membrane PA as compared to normals. No correlation between Stage of CLL and lymphocyte PA was observed. Likewise, an inhibitor of PA in CLL lymphocytes was not detected. The function of PA in normal B-lymphocyte physiology and the potential pathogenetic role of diminished PA in CLL lymphocytes remain to be explored.
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PMID:Plasminogen-dependent fibrinolytic activity in normal human lymphocytes: diminished lymphocyte plasminogen activator in chronic lymphocytic leukemia. 392 13

Plasminogen and plasmin have been determined in the same plasma samples in normal subjects and in various physiological and pathological conditions (pregnancy, liver cirrhosis, untreated cancer, and myocardial infarction during treatment with streptokinase) by means of two different methods. These were an enzymatic assay and a new immunochemical assay based on radial immunodiffusion employing cellulose acetate strips.A significant correlation was found in normal subjects. However, in the other conditions marked discrepancies were observed in the results by the two methods. These findings might be related to variations in the functional activity of plasminogen and plasmin in disease.
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PMID:Enzymatic and immunochemical determination of plasminogen and plasmin in different physiological and pathological states. 425 95

Immunization of a goat with partially reduced and S-carboxymethylated plasmin B-chain-alpha 2-antiplasmin complex resulted in a large population of antibodies with rather high specificity towards the complex. These antibodies do not react with plasminogen or plasmin in complex with other inhibitors than alpha 2-antiplasmin. However, they react fully with native alpha 2-antiplasmin, but a 200-fold higher concentration, as compared to plasmin-alpha 2-antiplasmin complex, is needed to obtain a similar displacement curve in a double-antibody radioimmunoassay. The results indicate a conformational change in the vicinity of the reactive site in alpha 2-antiplasmin, as a result of complex formation with plasmin. A method for determination of plasmin-alpha 2-antiplasmin complex in plasma has been elaborated using the described radioimmunoassay. About 1.5 mg plasmin-alpha 2-antiplasmin complex/l can be detected, which equals the condition when about 1% of the alpha 2-antiplasmin in plasma is in complex with plasmin. In normal individuals plasmin-alpha 2-antiplasmin complex could be detected only rarely. However, patient with acute processes, as evidenced by high fibrinogen levels, surgical patients postoperatively or patients with malignancy have often detectable levels.
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PMID:Determination of plasmin-alpha 2-antiplasmin complex in plasma samples by means of a radioimmunoassay. 619 54

The pre-treatment serum activities of several proteinase-like peptidases and the proteinase inhibitors, alpha 1-antitrypsin (alpha 1AT) and alpha 2-macroglobulin (alpha 2M), have been determined in 102 women with breast cancer and compared with those in 20 women with benign disease and in 30 healthy women of cancer bearing age. There were no significant differences in serum proteinase-like peptidase activities associated specifically with breast cancer. However, trypsin-like and plasmin-like activities were significantly lower than normal in women with breast disease. Serum alpha 1AT and alpha 2M levels were higher in patients with breast cancer than in healthy women or women with benign breast disease. These results indicate that, at presentation, breast cancer is not associated with abnormal serum levels of the proteinase-like peptidases studied, possibly as a result of an increase in the concentration of proteinase inhibitors.
Eur J Cancer Clin Oncol 1984 Feb
PMID:Serum proteinase-like peptidase activities and proteinase inhibitors in women with breast disease. 620 Mar 26

Hemostatic function of 129 patients with cancer of the digestive system was studied on the clinical point of view. Activator (A) and inhibitor (I) of fibrinolysis of 94 cancer tissues were determined by Malone's method. The following results were obtained: Latent DIC state was observed in the patients with advanced stage. Great majority of the patients with PT less than or equal to 85%, antithrombin III (AT III) less than or equal to 25 mg/dl, FDP greater than or equal to 5 micrograms/ml, alpha 1 antitrypsin (alpha 1 AT) greater than or equal to 340 mg/dl, plasminogen (plg) less than or equal to 10 mg/dl and alpha 2 plasmin inhibitor (alpha 2 PI) less than or equal to 80%, were eligible only for non-curative operation on the preoperative evaluations. Persistent decreases in PT, AT III, plg and alpha 2 PI mean poor prognosis, which were seen within about 6 months prior to death. In gastric cancer patients, these abnormalities showed correlations with serum choline-esterase, albumin and ferritin, and post-operative changes of these parameters suggested the recurrence. There were I activities in the cancer tissues which were scarcely detected in the normal tissues. Some differences in A/I ratios were observed on types of organs involved, histological types and differentiative degrees. There were no correlations between the hemostatic state and A/I ratios. These results indicate the clinical usefulness of the hemostatic functions of the cancer patients and the fibrinolytic properties of the cancer tissues, and also suggested that tumor bearing state, liver function and non-specific stimulating mechanisms participate in the appearance of the abnormalities.
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PMID:[Hemostatic abnormalities of the patients with cancer. Clinical significance and fibrinolytic properties of the cancer tissues]. 620 15

We carried on an investigation of proteases associated to human tumors by immunohistological techniques. Most of our work dealt with the plasmin system (plasminogen, its two activators and the two plasmin inhibitors, a 2 antiplasmin and a 2 macroglobulin). We found an antigen reacting with anti plasminogen serum in all the 30 colorectal adenocarcinomas we studied by immunofluorescence. This antigen was mainly plasminogen, as we could not detect active plasmin by a histochemical technique on sections of the same tumors. However it is likely that plasminogen present at the surface of tumor cells and on the contour of tumor foci, mainly in invasive areas, can be converted into plasmin, which in turn plays an important role in the degradation of basement membrane antigens. This makes easier tumor invasiveness and release of isolated tumor cells, ready for metastasizing. Plasmin action is likely of short duration and within short range, as this enzyme is rapidly neutralized by its inhibitors, both present at high concentration in the peritumoral stroma. Cathepsin B was characterized by immunoperoxidase method in many colorectal tumors. However our results are preliminary, so we cannot draw any conclusion on the role of this enzyme in tumor invasiveness.
Bull Cancer 1984
PMID:Proteases in human tumors. 624 Sep 98

A spontaneous mammary adenocarcinoma (AC) from an inbred female rat was investigated with regard to secretion of neutral proteases. Cultures of neoplastic epithelial cells derived from the tumour secreted an enzyme that fulfilled the criteria for a specific collagenase. In contrast to cultures of non-neoplastic cells, tumour collagenase was present as an active enzyme, since treatment with trypsin or p-aminophenylmercuric acetate (APMA) did not increase activity. The neoplastic cells were also prolific producers of plasminogen activator (PA). Dexamethasone (Dex) (10(-6)M) markedly reduced the levels of both enzymes. Addition of tranexamic acid (TA), an inhibitor of plasmin and of plasminogen activation, did not affect collagenase activity, even at 10(-1)M TA, nor did latent collagenase accumulate. Latent collagenase was secreted in culture by normal fibroblasts from neonatal rat lungs. This latent enzyme was activated by the addition of tumour cell medium plus plasminogen, but this effect was inhibited by the addition of TA. These results demonstrate that the neoplastic cells themselves secrete collagenase as an active enzyme. PA is also secreted, is not involved with tumour collagenase, but is capable, in the presence of plasminogen, of activating latent collagenase produced by the non-neoplastic cells within the tumour or in the surrounding tissue. This tumour possesses potent collagenolytic ability in vitro which may be partly responsible for its rapid invasion in vivo.
Int J Cancer 1981 Oct 15
PMID:Rat mammary carcinoma cells secrete active collagenase and activate latent enzyme in the stroma via plasminogen activator. 627 36

The relationship of a basement membrane collagen degrading enzyme (BM collagenase) and plasminogen activator (PA) was studied in a number of non-malignant and malignant human and murine cell lines. Several non-malignant cell lines secreted significant amounts of PA but not detectable BM collagenase activity whereas the malignant cell lines, with one exception, secreted both enzymes. Therefore, the secretion of BM collagenase appears to be a characteristic of many malignant cells whereas PA is synthesized also by normal cells. The BM collagenase needed proteolytic activation for maximal activity indicating that it is secreted in a latent form. The addition of plasminogen to the culture medium of human fibrosarcoma cells (HT-1080) resulted in maximal activation of the enzyme. Plasmin, but not plasminogen, increased the activity of partially purified enzyme protein. Accordingly, the activation of latent BM collagenase in vivo may be facilitated by PA through the conversion of plasminogen to plasmin. It is suggested that the secretion of BM collagenase concomitantly with PA is a prerequisite for metastasis.
Int J Cancer 1982 Nov 15
PMID:Secretion of basement membrane collagen degrading enzyme and plasminogen activator by transformed cells--role in metastasis. 629 70

Plasminogen activator is a protease which catalyses the conversion of the inactive plasminogen to the active plasmin. Most transformed cell lines and solid tumors produce elevated levels of plasminogen activator compared with nontransformed counterparts. This increased synthesis of plasminogen activator may play a role in tumorigenesis, cancer invasion and metastasis. Measurement of plasminogen activator in tumor extracts and body fluids may provide diagnostic and prognostic information. Finally, since plasminogen activator is an estradiol-inducible enzyme, its measurement in breast carcinomas might be a marker for a functional estrogen receptor.
Eur J Cancer Clin Oncol 1984 May
PMID:Plasminogen activator and cancer. 637 29


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