Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Changes of prekallikrein in the cases with DIC were investigated, i.e., DIC cases including disseminated metastasis of gastric cancer, acute promyelocytic leukemia and endotoxin shock. Therefore, the trigger substances for this paper were the pathologic cells of the leukemia, the cultured well differentiated adenocarcinoma cells and endotoxin. (1) The lysates of the pathologic cells of the leukemia and the cultured cells showed prekallikrein activation. Endotoxin showed prekallikrein activation via factor XII. (2) Serine proteases (factor Xa, thrombin, plasmin and trypsin) activated prekallikrein in the plasma and the purified prekallikrein. (3) Antithrombin III, aprotinin and FOY inhibited prekallikrein activation. Antithrombin III was promoted by heparin in its inhibitory effect.
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PMID:Changes of prekallikrein in the cases with disseminated intravascular coagulation syndrome. 16 Jan 91

The precursor of matrix metalloproteinase 9 (proMMP-9), also known as '92 kDa progelatinase/type IV procollagenase', was purified from the conditioned medium of U937 monocytic leukaemia and HT1080 fibrosarcoma cell lines stimulated with phorbol 12-myristate 13-acetate. ProMMP-9 in these culture media is non-covalently complexed with the 29 kDa tissue inhibitor of metalloproteinases (TIMP), but free proMMP-9 was separated from the TIMP-proMMP-9 complex by chromatography on Green A Dyematrex gel. The final product was homogeneous on SDS/PAGE, with a molecular mass of 88 kDa without reduction and 92 kDa with reduction. Treatment of proMMP-9 with 4-aminophenylmercuric acetate converted the 88 kDa precursor into 80 kDa and 68 kDa forms. Gelatin-containing zymographic analysis showed zones of lysis associated with all three species. However, only the 68 kDa species was shown to be catalytically active by its ability to bind to alpha 2-macroglobulin. In the presence of an equimolar amount of TIMP, only the 80 kDa species was generated by treatment with 4-aminophenylmercuric acetate, but no enzyme activity was detected. This indicates that TIMP binds to the 80 kDa intermediate and inhibits the generation of the active 68 kDa species. Eight endopeptidases (trypsin, chymotrypsin, plasmin, plasma kallikrein, thrombin, cathepsin G, neutrophil elastase and thermolysin) were tested for their ability to activate proMMP-9. Of them, trypsin was the most effective activator of proMMP-9. Only partial activation (10-30%) was observed with plasmin, cathepsin G and chymotrypsin. The active forms generated by trypsin were identified as 80 kDa, 74 kDa and 66 kDa by their abilities to bind to alpha 2-macroglobulin. In the presence of an equimolar amount of TIMP, proMMP-9 was also converted into the same molecular-mass species by trypsin, but they were not proteolytically active. This suggests activated MMP-9 is inhibited by TIMP. Activated MMP-9 digested gelatin, type-V collagen, reduced carboxymethylated transferrin and, to a lesser extent, type-IV collagen and laminin A chain. The specific activity against gelatin was estimated to be 15,000 units/mg (1 unit = 1 microgram of gelatin degraded/min at 37 degrees C) by titration with alpha 2-macroglobulin. Comparative studies on digestion of gelatin and collagen types IV and V by MMP-9 and MMP-2 indicated that both enzymes degrade these substrates into similar fragments. However, the susceptibilities of laminin, fibronectin and reduced carboxymethylated transferrin to these two MMPs were sufficiently different to indicate differences in substrate specificities between these two closely related proteinases.
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PMID:Purification and characterization of matrix metalloproteinase 9 from U937 monocytic leukaemia and HT1080 fibrosarcoma cells. 137 48

Human RC2A myelomonocytic leukemia cells are able to activate the prourokinase (pro-u-PA) they secrete so that active u-PA is present both in serum-free conditioned medium from these cells, as well as on the cell surface. When the cells are grown in serum-containing medium, no u-PA activity can be found in the medium but active u-PA is found bound to the cell surface where it can generate bound plasmin. This distribution of u-PA activity was shown to be, first, the net result of slow inactivation of free active u-PA by serum inhibitor(s) and simultaneous rapid uptake of u-PA onto the cell surface. Binding to cells was at least six times faster than inactivation by 10% serum. The principal serum inhibitor of u-PA was identified as alpha 2-macroglobulin (alpha 2M), and prior inactivation of u-PA by purified human alpha 2M was also shown to prevent uptake of u-PA activity onto cells. Second, although endogenous u-PA could form covalent complexes with purified alpha 2M in the culture medium of RC2A cells, covalent alpha 2M complexes were not formed by u-PA on the cell surface; the u-PA taken up in this compartment was protected against alpha 2M inhibition. u-PA anchored to plastic surfaces via monoclonal antibodies to the amino-terminal region of u-PA was also protected against alpha 2M, suggesting that the protection of cell surface u-PA results from a steric effect. These results provide evidence as to how the active u-PA produced by leukemia cells can contribute to proteolytic activity on their cell surface in the presence of serum inhibitors.
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PMID:Alpha 2-macroglobulin restricts plasminogen activation to the surface of RC2A leukemia cells. 172 17

In order to define a specific acceleration of fibrinolytic activity in acute promyelocytic leukemia (APL), we determined fibrinolytic factors in APL and acute myeloblastic leukemia (AML). An increase in plasma levels of D-dimer was observed in both APL and AML, indicating that there is an acceleration of fibrinolysis in both types of leukemia. The levels of D-dimer/FDP ratio were significantly lower in APL than AML. These findings suggest that fibrinogenolytic activities were higher in APL that in AML. The relationship between the plasma levels of plasmin alpha 2PI complex (PIC) and FDP was investigated to study whether fibrinolysis was induced by plasmin. PIC levels were linearly correlated with FDP levels in AML, while in APL there was no close correlation between the plasma levels of PIC and FDP. Then, we measured PMN elastase-alpha 1 proteinase inhibitor complex (E-alpha 1 PI). There was a correlation between the plasma levels of E-alpha 1PI and FDP in APL but not in AML. Furthermore, PMN elastase activity was detected in leukemic cell lysate in patients with APL but not in AML. These findings suggest that PMN elastase may be an important factor in the induction of fibrinolysis in APL.
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PMID:[Role of PMN elastase in fibrinolytic activity in patients with acute promyelocytic leukemia]. 224 16

We present the case of a young man with acute monocytic leukemia (French-American-British classification:M5) and systemic hyperfibrinolysis with severe bleeding. Although fibrinolysis is usually mild and secondary to disseminated intravascular coagulation, its role as a primary and dominant factor in rare cases of leukemia warrants that its presence be sought as a cause of abnormal bleeding. Decreased serum plasminogen and increased serum plasmin determined by synthetic substrate assay and a negative protamine paracoagulation test are crucial findings. Use of high-dose epsilon-aminocaproic acid was effective in treating this complication. A transient increase in fibrinolytic activity coincident with the early effect of antileukemic treatment suggested that plasminogen activator and/or fibrinolytic protease substances were released from leukemic cells. Fibrinolytic activity subsequently disappeared with reduction in the population of leukemic cells.
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PMID:Primary fibrinolysis in acute monocytic leukemia. 276 88

The concentrations of elastase-alpha 1-proteinase inhibitor (E-alpha 1 PI) complex were assayed in 43 patients with various types of leukemia. Marked to moderate elevation of E-alpha 1 PI complex levels was observed in patients with acute myelocytic leukemia (AML), acute promyelocytic leukemia (APL), acute myelomonocytic leukemia (AMMoL), or chronic myelocytic leukemia (CML) at diagnosis. The ratio of E-alpha 1 PI complex concentrations in plasma to leukocyte counts markedly elevated in the patients with APL, especially. During the course of remission induction therapy, levels of E-alpha 1 PI complex decreased in parallel with decline of leukocyte counts in the patients with leukemia other than APL, however the E-alpha 1 PI complex was persistently elevated regardless of leukopenia in some patients with APL. In APL, concentrations of fibrin/fibrinogen degradation products (FDP) markedly increased even when levels of plasmin-alpha 2-antiplasmin complex were within normal limits. However, levels of E-alpha 1 PI complex usually increased in these cases. From these results, it is strongly suggested that promyelocytes contain markedly elevated amounts of elastase which participates in degradation of fibrin or fibrinogen in some cases of APL.
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PMID:Quantitative estimation of elastase-alpha 1-proteinase inhibitor (E-alpha 1 PI) complex in leukemia: marked elevation in cases of acute promyelocytic leukemia. 278 34

Plasma D-dimer was measured and compared with serum fibrinogen/fibrin degradation product levels (FDPs) in patients with disseminated intravascular coagulation (DIC) and other conditions associated with a hypercoagulable state. D-dimer (N less than 200 ng/ml) was elevated in all 43 patients with DIC, in 48 of 59 patients with liver disease, in 22 of 27 patients with acute leukaemia at presentation, in 17 of 23 patients with malignant disease, in 29 of 39 women in the third trimester of a complicated pregnancy, in 17 of 18 patients with deep venous thrombosis and in only four of 27 patients with acute myocardial infarction. There was a significant correlation between plasma D-dimer and serum FDP levels (P less than 0.01) as follows; DIC: r = 0.58, liver disease: r = 0.57, acute leukaemia: r = 0.84, malignancy: r = 0.87. The frequent elevation of D-dimer observed in liver disease, acute leukaemia, malignancy and complicated pregnancy indicates that a hypercoagulable state is a common occurrence in these conditions although in liver disease elevated levels resulting from a failure of normal clearance mechanisms cannot be excluded. The close relationship between D-dimer and FDP levels suggests that serum FDPs predominantly arise from the interaction of plasmin with crosslinked fibrin rather than with fibrinogen in the conditions in which these were compared.
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PMID:Plasma D-dimer levels and their relationship to serum fibrinogen/fibrin degradation products in hypercoagulable states. 291 30

Guanidinobenzoatase is a proteolytic enzyme capable of degrading fibronectin and is a tumour associated enzyme. Guanidinobenzoatase has been shown to be an arginine selective protease and is distinct from trypsin, plasminogen activator, plasmin, thrombin and a newly described tumour associated enzyme specific for guanidino phenylalanine residues. These conclusions have been derived from inhibition studies employing 4-methyl-p-guanidinobenzoate as substrate. Three active site titrants for trypsin have been shown to be good substrates for guanidinobenzoatase. A new active site titrant for trypsin, rhodamine bisguanidinobenzoate, can also be used to assay guanidinobenzoatase in a stoichiometric manner. This active site titrant can be employed to label guanidinobenzoate on the surface of leukaemia cells.
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PMID:Further inhibition studies on guanidinobenzoatase, a trypsin-like enzyme associated with tumour cells. 333 44

Thrombin generation, plasmin formation and non-specific protease activity, were assessed in a cohort group of 30 patients presenting with acute leukaemia. Abnormalities detected by specific tests of one or more of these three systems were found in 27 (90%) of patients while abnormalities in 'routine' laboratory coagulation tests were seen in only 17 (56%). All patients at presentation had a bleeding tendency which was defined as minor (skin purpura) or major (other bleeding sites). Patients presenting with minor (n = 19) or major haemorrhage (n = 11) could not be differentiated by the degree of thrombocytopenia. Similarly, increased generation of either thrombin or plasmin activity alone was non-discriminatory. However, more complex alterations of haemostasis involving increased activity of more than one of these three systems were seen only in those patients who had major haemorrhage.
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PMID:Combinations of increased thrombin, plasmin and non-specific protease activity in patients with acute leukaemia. 622 1

We have studied the main protease inhibitors of leukocytes, alpha-1-protease (alpha 1-PI), alpha-1-antichymotrypsin (alpha 1-Achy) and alpha-2-macroglobulin (alpha 2-M), as well as different parameters of coagulation and fibrinolysis in 21 cases of acute nonlymphoblastic leukemia (ANLL) before, during and after therapy. Nine of the patients presented signs of DIC, 8 of whom belonged to subtype M3 and to subtype 1 M1. The initial alpha 1-PI and alpha 1-Achy levels, which were elevated, increased during the treatment period. There was no significant difference between patients with and without DIC. However, those leukemic patients with DIC showed a significant decrease in plasminogen (p less than 0.005) and fast antiplasmin (p less than 0.01) only during the treatment compared with DIC free patients. All DIC cases demonstrated circulating plasmin-antiplasmin complex (P-AP) both before and during treatment. Independent of a possible proteolytic action of leukocyte enzymes on clotting factors in the clinical course of ANLL (mainly M3 subtype), our results suggest an activation of plasmin-mediated fibrinolysis related to the activation of plasminogen by leukocytes, reactive DIC or both.
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PMID:Changes in plasma levels of protease and fibrinolytic inhibitors induced by treatment in acute myeloid leukemia. 623 45


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