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

L-Asparaginase (ASP), a chemotherapeutic agent used in the treatment of children with acute lymphoblastic leukaemia (ALL), is linked to thromboembolic complications secondary to an acquired deficiency of antithrombin III (ATIII). Fresh frozen plasma (FFP) is used to prevent and/or treat thrombotic complications in these children. However, the effect of FFP on plasma concentrations of ATIII and biochemical markers of activation of coagulation has never been tested. In this study, FFP (20 ml/kg) was administered to eight children with ALL receiving ASP in the consolidation phase of their treatment. Plasma samples were drawn pre-infusion, and following infusion at 1, 24, and 48 hr. Prior to the FFP infusions, plasma concentrations of prothrombin, fibrinogen, alpha 2-macroglobulin, heparin cofactor II, protein C, and protein S were similar to levels in healthy children. Only plasma concentrations of ATIII were significantly decreased (0.55 U/ml). Following FFP infusions, there was no statistical or clinically important increase in plasma concentrations of any coagulation protein at any time point. Pre-infusion plasma concentrations of markers of endogenous thrombin generation (thrombin-antithrombin III complexes (TAT)) and activation of the fibrinolytic system in response to activation of the coagulation system (D-dimer levels) were significantly increased. However, FFP had no statistical or clinically important effect on concentrations of these markers. We conclude that FFP administration for the prevention and treatment of acquired ATIII deficiency secondary to ASP has no demonstrable benefit on plasma levels of coagulation proteins and is unlikely to be of clinical benefit.
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PMID:Fresh frozen plasma has no beneficial effect on the hemostatic system in children receiving L-asparaginase. 752 13

APL-associated hemostasis disorders result from at least two distinct mechanisms due to the release of procoagulant activities and plasminogen activators from the leukemic cells. These two mechanisms (thrombin activation and plasmin activation) may cleave the fibrinogen molecule, but their respective roles in low fibrinogen levels and bleeding diathesis genesis remain in dispute. In vivo ATRA therapy induces a rapid correction of both low fibrinogen level and bleeding tendency, but no clear explanation of this beneficial effect has been proposed. We prospectively investigated 27 APL patients at presentation for diffuse intravascular coagulation (DIC) markers (prothrombin activation fragment and thrombin/antithrombin complexes) and plasmin-dependent primary fibrinogenolysis markers (alpha 2 plasmin inhibitor consumption +/- plasmin/alpha 2 plasmin inhibitor complexes). Fourteen of these patients were then serially studied during the first 2 weeks of ATRA therapy. Four of them, however, developed an hyperleukocytosis requiring additional chemotherapy before the end of the 2nd week. At presentation, low level of fibrinogen was clearly associated with alpha 2 plasmin inhibitor deficiency (p < 0.01), while DIC was equally present in fibrinogenopenic and non-fibrinogenopenic patients. Moreover, was observed a rapid simultaneous correction of low fibrinogen levels and plasmin activation markers in APL patients undergoing ATRA therapy (before day 5), but a more prolonged persistence of DIC markers (until day 14). Initial bleeding syndrome seemed more frequent in patients with initial low fibrinogen level. These data indicate that plasmin-dependent primary fibrinogenolysis is the major etiologic factor of low fibrinogen level in APL patients. In vivo differentiation ATRA therapy induces a rapid decrease in the plasmin activation and a normalization of fibrinogen level, while DIC may in vivo persist for several weeks. Prospective studies evaluating antifibrinolytic agents as therapy of APL-associated hemostasis disorders should be considered. Additionally, prophylactic heparin therapy might be useful after day 5 in patients undergoing ATRA therapy, since they present a prolonged procoagulant tendency.
Leukemia 1995 Jan
PMID:In vivo thrombin and plasmin activities in patients with acute promyelocytic leukemia (APL): effect of all-trans retinoic acid (ATRA) therapy. 753 Dec 60

Both normal and leukaemic human megakaryocytopoiesis are stimulated by several cytokines, including stem cell factor, granulocyte-macrophage colony stimulating factor (GM-CSF), interleukin-3, GM-CSF/interleukin-3 fusion protein, interleukin-6, interleukin-11, basic fibroblast growth factor and thrombopoietin, but are inhibited by tumour necrosis factor-alpha, platelet factor 4, beta-thromboglobulin, thrombin, interleukin-4, interferon-alpha and interferon-gamma. Human megakaryoblastic leukaemia cell lines have common biological features, including high expression of the megakaryocytic specific antigen: CD41; high expression of the early myeloid antigens: CD34 and CD33; constitutive expression of interleukin-6 and platelet-derived growth factor; complex karyotype picture; expression of c-kit: the stem cell factor receptor; growth-dependency or -stimulation by stem cell factor, interleukin-3 and/or GM-CSF; megakaryoblastic differentiation by phorbol-myristate-acetate; and in vivo tumorigenicity in mice is associated with marked fibrosis. Only a few agents including phorbol-myristate-acetate; vitamin D3, interferon-alpha, interferon-beta 2, erythropoietin and thrombin have been reported to induce megakaryocytic differentiation in the human megakaryoblastic leukaemia cells.
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PMID:Characteristic biological features of human megakaryoblastic leukaemia cell lines. 756 68

Receptor-induced binding of the stable GTP analogue, guanosine 5'-[gamma-thio]triphosphate (GTP [gamma S]), to guanine nucleotide-binding regulatory proteins (G proteins) was measured in various permeabilized cells. In myeloid differentiated human leukemia (HL-60) cells, permeabilized with either digitonin, streptolysin O or Staphylococcus aureus alpha-toxin, binding of GTP[gamma S] induced by three distinct chemoattractant receptors was observed. The extent of receptor-stimulated GTP[gamma S] binding (maximally about 2-fold) was independent of the type of permeabilizing agent used. In human erythroleukemia cells permeabilized with digitonin, agonist activation of thrombin and neuropeptide Y receptors increased GTP[gamma S] binding by 1.8- and 1.5-fold, respectively. Finally, in adherently grown human embryonic kidney cells permeabilized with digitonin, activation of the stably expressed human muscarinic m3 receptor increased GTP[gamma S] binding by about 1.6-fold. In digitonin-permeabilized HL-60 cells, a quantitative analysis of formyl peptide receptors and interacting G proteins was performed. About 50,000 formyl peptide receptors per cell were detected. Agonist binding to these receptors was fully sensitive to regulation by guanine nucleotides and pertussis toxin. The number of high-affinity GTP[gamma S] binding sites, most likely representing heterotrimeric G proteins, was calculated to be about 670,000 per cell. Stimulation of formyl peptide receptors led to the activation of about 130,000 of high-affinity GTP[gamma S] binding sites, indicating a ratio of about three activated G proteins per one agonist-activated receptor.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Analysis of receptor-G protein interactions in permeabilized cells. 763 Apr 24

Disseminated intravascular coagulation (DIC) is characterized by extreme activation of intravascular coagulation, and clinical manifestations such as bleeding and/or multiple organ failure is sometimes observed in advanced cases of DIC. The balance of coagulation and fibrinolysis activation varies according to the underlying diseases of DIC. DIC cases are classified as the type with predominant coagulation activation and the type with predominant fibrinolysis activation in former type plasma levels of thrombin-antithrombin III complex (TAT) are greatly increased, and those of plasmin-alpha 2 plasmin inhibitor complex (PIC) are slightly increased. In addition plasma levels of plasminogen activator inhibitor 1 (PA1) are greatly increased, multiple organ failure is a major clinical manifestation in advanced cases and sepsis is a representative underlying disease. In the second type both plasma levels of TAT and PIC are greatly increased, plasma levels of PA1 are almost within normal limits. Bleeding is a major clinical manifestation in advanced cases and acute promyelocytic leukemia (APL) is a representative underlying disease. The classification of DIC should be considered when choosing treatment with DIC. Diagnosis of pre-DIC status is based on gradually decreasing platelets counts in sepsis and on mild elevation of FDP and D dimer in APL, leukemia and cancer.
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PMID:[Classification and treatment of DIC]. 778 36

Acute promyelocytic leukemia (APL) has been historically characterized by a high rate of early hemorrhagic death, particularly from intracranial bleeding. The hemorrhagic complications have been attributed to a combination of intravascular thrombin generation, excessive fibrinolysis and/or proteolytic activities released from blast cells. Before the era of all-trans retinoic acid (ATRA), the incidence of early fatal bleeding in recent series has ranged from 8 to 46%, and no anti-hemorrhagic treatment clearly appeared superior in abating this complication. This uncertainty is due to remain because of the lack of prospective studies. The increasing awareness of the need for prompt diagnosis and treatment of APL and the larger availability of supportive therapy has largely contributed to lessen the incidence of fatal bleeding, which can be reliably estimated around 10% in major centers. Groups pioneering the use of ATRA have reported a rapid improvement of the coagulopathy of APL, usually starting 48 h from the beginning of the treatment. However, the hemostatic changes during ATRA have been monitored only in a few patients and recent results suggest that hyperfibrinolysis/proteolysis is rapidly corrected by ATRA, whereas thrombin generation may persist longer. Moreover, although significantly less frequent, fatal bleeding may occur during ATRA and thrombotic events have also been reported so that hemostatic death rate is also approximately 10% in patients treated with ATRA. The combination of chemotherapy plus ATRA administration during induction has been suggested as a useful means of controlling hyperleukocytosis, and this could contribute in abating this unacceptably high rate of early death. On the other side, chemotherapy can dramatically exacerbate clotting abnormalities leading to catastrophic clinical outcomes. Thus, more detailed studies of the coagulopathy of APL and its changes during treatment with ATRA, or ATRA combined with chemotherapy, are required in order to offer the most appropriate treatment to these patients still at risk of severe bleeding and thrombotic complications.
Leukemia 1994
PMID:The pathophysiology and treatment of hemorrhagic syndrome of acute promyelocytic leukemia. 781 32

The hemostatic function of 40 feline immunodeficiency virus (FIV) seropositive and 8 FIV and feline leukemia virus (FeLV) seropositive cats was evaluated and compared with reference values from 30 clinically healthy cats. The FIV-positive cats were divided into 3 groups: group I included asymptomatic carriers; group II comprised sick FIV-infected cats with illnesses not likely to influence the hemostatic system; and group III included FIV-positive cats with diseases potentially associated with coagulopathies. Platelet counts in FIV/FeLV-infected cats were significantly lower than in healthy cats (P < .003), whereas the differences in the 3 groups of FIV-positive cats were variable (group I, P = .009; II, P = .05; III, P = .09). Thrombocytopenia (< 145,000 platelets/microL) was present in 4 FIV-positive and 3 FIV/FeLV-positive cats. Platelet aggregation induced by collagen (0.5 and 0.25 micrograms/mL), adenosine diphosphate (ADP) (1 and 0.6 mumol/L), and thrombin (0.4 and 0.25 IU/mL) was not significantly different from that of healthy cats. The plasma coagulation system was evaluated by measuring one-stage prothrombin time (OSPT), activated partial thromboplastin time (APTT), thrombin time, fibrinogen concentration, coagulation factor assays, fibrinogen and fibrin degradation products (FDP), and plasma exchange test. The OSPT was similar in FIV-seropositive cats and in the healthy control group. Cats with FIV infection, however, had markedly shorter clotting times than healthy cats when using a modified test system (P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hemostatic disorders in feline immunodeficiency virus-seropositive cats. 783 13

Plasma levels of thrombin-antithrombin III complex (TAT), plasmin-alpha 2-plasmin inhibitor complex (PIC) and active plasminogen activator inhibitor (PAI) were assayed in 66 cases of disseminated intravascular coagulation (DIC). Significant elevation of both TAT and PIC was observed in all cases of DIC. Most elevated levels of TAT were seen in DIC with acute promyelocytic leukaemia (APL) and sepsis. The highest levels of PIC were seen in DIC with APL but were much lower in sepsis. A significant elevation in active PAI was observed in DIC due to acute leukaemia (apart from APL), chronic myeloid leukaemia and sepsis, but not in APL, non-Hodgkin lymphoma and cancer. Active PAI was higher in patients with multiple organ failure (MOF) than in those without MOF while PIC was lower in patients with this complication. Thus, the balance of coagulation and fibrinolysis varied according to the underlying cause of DIC; APL had more dominant activation of fibrinolysis, while sepsis had greater activation of coagulation. It is suggested that the inhibition of secondary fibrinolytic activation plays an important role in the progression of MOF by the disturbance of the microcirculation.
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PMID:Study of the balance between coagulation and fibrinolysis in disseminated intravascular coagulation using molecular markers. 786 91

The cytokine melanoma growth-stimulating activity (MGSA) is a growth factor for melanoma cells and a chemotaxin for neutrophils. Known purification procedures of MGSA from human sources or expression systems give a low yield and require multiple chromatography steps. Here, a fast and high-yield method for the purification of recombinant MGSA is described. Approximately 500 micrograms MGSA were recovered from the bacterial lysate of a 10 liter culture within a day. For this purpose, total mRNA of Hs294T melanoma cells was isolated and cDNA of MGSA was obtained by reverse transcription and polymerase chain reaction. The cDNA of MGSA was subcloned into the expression vector pGEX-2T, generating a fusion with the Schistosoma japonicum glutathione S-transferase gene. The fusion protein was expressed in E. coli DH5a and purified from the bacterial lysate using glutathione-sepharose beads. MGSA was cleaved from the complex of fusion protein and glutathione-sepharose beads with thrombin and purified to homogeneity by anion-exchange high-performance liquid chromatography with a Mono-S-column. The bioactivity of the recombinant MGSA was assessed by chemotactic migration and triggered [Ca2+]i-transients in human neutrophils. In addition, [125I]MGSA bound specifically to undifferentiated human leukemia cells HL-60 transfected with the cDNA of the interleukin-8 (IL-8) receptor beta with similar properties as [125I]IL-8. Thus, this described method might be a powerful tool to generate large amounts of cytokines in a short time.
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PMID:Single-step purification of recombinant melanoma growth-stimulating activity by anion-exchange high-performance liquid chromatography. 792 55

Monocytes/macrophages and endothelial cells express tissue factor (TF), an initiator for blood clotting pathway, following their activation accompanied by immune response and/or inflammation. This TF expression results in thrombin generation and fibrin formation around these cells and possibly participates in host-defense mechanism. TF expression by these cells is also a risk-factor to vascular diseases including arteriosclerosis and thrombosis. In cancer and leukemia patients elevation of their plasma TF level associated with DIC and related coagulation disorders.
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PMID:[Current scopes on tissue factor: its physiological function and relationship with coagulation diseases]. 802 93


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