Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It has repeatedly been proposed that fibrin plays a role in tumor growth and metastasis. Among tumor cell products or activities which may promote clot formation, cancer procoagulant (CP), a direct activator of coagulation factor X, has been suggested to be selectively associated with the malignant phenotype. We report here the enzymatic and immunological identification of this cysteine proteinase procoagulant in extracts and cells from human melanoma. CP activity was independent of both the intrinsic and extrinsic pathways of blood coagulation, using factor IX and factor VII deficient plasmas, and was inhibited by the cysteine proteinase inhibitors iodoacetamide and HgCl2. CP activity was detectable in extracts and cell suspensions from all 32 patients studied and was higher in extracts from metastases (14.8 +/- 3.9 units/mg protein) than from the primary tumors (3.7 +/- 1.0 units/mg protein). CP activity was not affected by an anti-apoprotein III antibody or by concanavalin A, a known inhibitor of thromboplastin. In contrast, no CP activity or antigen was detected in extracts from six benign melanocytic lesions. The procoagulant activity was dependent on factor VII and was inhibited by anti-apoprotein III antibody and by concanavalin A, properties that suggest that the procoagulant was tissue thromboplastin. These data indicate that CP can be expressed by human tumor cells and that, among melanotic lesions, its presence is associated with the malignant phenotype and its activity is particularly high in metastatic cells.
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PMID:Cancer procoagulant in human tumor cells: evidence from melanoma patients. 353 81

Cancer procoagulant, a proteolytic procoagulant enzyme, has been purified from rabbit V2 carcinoma extracts by two procedures. In the first, the protein was purified by benzamidine--Sepharose affinity chromatography, gel filtration chromatography, and phenyl-Sepharose hydrophobic chromatography. Antiserum was raised against the purified protein and was used to prepare an immunoadsorbent column. In the second, tumor extracts were purified by immunoaffinity chromatography followed by p-(chloromercuri)benzoate affinity chromatography. The second procedure was substantially quicker and easier. The final product of both procedures was homogeneous on the basis of analytical sodium dodecyl sulfate--polyacrylamide gel electrophoresis and isoelectric focusing. The molecular weight was 68 000 and the isoelectric point 4.8. The proteinase activity of cancer procoagulant directly activated factor X, in the absence of factor VII, and was inhibited by 1 mM iodoacetamide and 0.1 mM mercury which are classic cysteine proteinase inhibitors. A carbohydrate analysis showed less than 1 mol of hexose or sialic acid/mol of protein. The amino acid analysis showed that serine (19.1%), glycine (18.77%), and glutamic acid (12.5%) were the prevalent amino acids. The amino acid composition of cancer procoagulant was substantially different than other known factor X activating proteinases or other cysteine proteinases including cathepsin B.
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PMID:Isolation and characterization of cancer procoagulant: a cysteine proteinase from malignant tissue. 393 63

Cancer cells may promote fibrin formation in the tumor microenvironment through availability of procoagulant activities which are mainly of two types: tissue thromboplastin-like or direct activator of coagulation factor X. The pharmacological modulation of these activities could be potentially important in the control of metastasis growth. However, very limited information is available so far on this issue; it has recently been shown that the direct activator of coagulation factor X is a vitamin K-dependent activity which is depressed by warfarin treatment, not by anticoagulation with heparin or defibrinating enzymes. Whether the inhibition of this peculiar cancer procoagulant is involved in the antimetastatic activity of warfarin is a stimulating hypothesis which needs to be further substantiated.
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PMID:Cancer cell procoagulants and their pharmacological modulation. 639 43

Thrombosis is the most frequent complication and the second cause of death in patients with overt malignant diseases. Increasing evidence suggests that thrombotic episodes may also precede the diagnosis of cancer by months or years thus representing a potential marker for occult malignancy. Recently, emphasis has been given to the potential risk of cancer therapy (both surgery and chemotherapy) in enhancing the risk for thromboembolic disease. Post-operative deep-vein thrombosis is indeed more frequent in patients operated for malignant diseases than for other disorders. On the other hand, both chemotherapy and hormone therapy are associated with an increased thrombotic risk, which can be prevented by low-dose oral anticoagulation. Possible contributory causes for thromboembolic disease in cancer include the capacity of tumor cells and their products to interact with platelets, clotting and fibrinolytic systems, as well as their interactions with endothelial cells and tumor-associated macrophages. In particular, procoagulant activities of tumor cells have been extensively studied; one of these, cancer procoagulant, could represent a novel marker of malignancy in both solid tumors and acute promyelocytic leukemia (APL). In solid tumors, CP, a vitamin K dependent enzyme could represent the selective target of the antimetastatic effects of warfarin treatment. In APL, CP may contribute to trigger the well known intravascular coagulation syndrome accompanying the early manifestations of the disease and is depressed by all-trans-retinoic acid, an agent capable to determine complete remission with a rapid amelioration of the bleeding syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Cancer and thrombosis: from Phlegmasia alba dolens to transgenic mice. 857 72

Thrombin-catalyzed, cross-linked fibrin (XLF) formation is a characteristic histopathological finding in many human and experimental tumors and is thought to be of importance in the local host defense response. Although the pathogenesis of tumor-associated fibrin deposition is not entirely clear, several tumor procoagulants have been described as likely primary stimuli for the generation of thrombin (and XLF) in the tumor microenvironment (TME). In a previous study of a variety of human tumors we have shown that tissue factor (TF) is the major procoagulant. However, the relative contribution to fibrin deposition in the TME of tumor cell TF and host cell TF (eg, macrophage-derived) was not established. In addition, recent evidence has implicated TF in the regulation of the synthesis of the pro-angiogenic factor vascular endothelial growth factor (VEGF) by tumor cells. In the current study we used in situ techniques to determine the cellular localization of XLF, TF, VEGF, and an alternative tumor procoagulant, so-called cancer procoagulant (CP), a cysteine protease that activates clotting factor X. In lung cancer we have found XLF localized predominantly to the surface of tumor-associated macrophages, as well as to some endothelial cells and perivascular fibroblasts in the stromal area of the tumors co-distributed with TF at the interface of the tumor and host cells. Cancer pro-coagulant was localized to tumor cells in several cases but not in conjunction with the deposition of XLF. TF and VEGF were co-localized in both lung cancer and breast cancer cells by in situ hybridization and immunohistochemical staining. Furthermore, a strong relationship was found between the synthesis of TF and VEGF levels in human breast cancer cell lines (r2 = 0.84; P < 0.0001). Taken together, these data are consistent with a highly complex interaction between tumor cells, macrophages, and endothelial cells in the TME leading to fibrin formation and tumor angiogenesis.
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PMID:Activation of coagulation and angiogenesis in cancer: immunohistochemical localization in situ of clotting proteins and vascular endothelial growth factor in human cancer. 946 66

Hemostatic abnormalities associated with malignant disease led to the search for and discovery of a proteolytic enzyme that activated factor X in the blood coagulation cascade. It was named cancer procoagulant (CP). CP is a cysteine proteinase that is found in malignant and fetal (human amnion-chorion) tissue; it has not been found in normally differentiated tissue. It is a calcium-dependent, Mn2+ stimulated enzyme that has enhanced activity and inhibition in a reduced environment. This review presents a complete compilation and discussion of the known chemical and enzymatic characteristics of CP as well as many purification and assay procedures. Several unique properties of these procedures are described. Some problems and controversies are highlighted in each of the sections. An immunoassay for CP as a tumor marker and some of its potential applications in the diagnosis and monitoring of cancer are reviewed. Some therapeutic implications of CP are noted in light of the observation that antibodies to CP block the metastatic seeding of lung colonies in vivo and diminish the viability of tumor cells in vitro. Finally, comments about the relationship between tissue factor and CP in the malignant cells are provided.
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PMID:Cancer procoagulant: a factor X activator, tumor marker and growth factor from malignant tissue. 951 49

Thromboembolic complications are a very important part of neoplastic diseases. In these complications specific processes participate which are the result of the action of substances produced by the tumour or they are formed as a consequences of the reaction to the neoplastic disease, its complications or treatment. A special role in this respect is played by the tissue factor and cancer procoagulant which are very important procoagulant proteins. Post-mortem evaluation reveals thromboembolic manifestations in as many as 50% of all oncological patients. Considerable attention is paid to the prevention of thromboembolic episodes or their progression and patterns for their prevention and treatment were elaborated. One of these provisions is the use of anti-thrombotic drugs, their introduction being motivated by an attempt to check coagulation and eliminate its tendency towards hypercoagulation. In this respect the importance of heparin is beyond doubt, i.e. of non-fractionated as well as low-molecular heparin.
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PMID:[Activation of blood coagulation in oncology patients]. 960 60

This study aimed at evaluating diagnostic significance of cancer procoagulant (CP) activity in the homogenates of colon cancer tissues and in blood serum of patients with this neoplasm. Procoagulant activity, depending of specific cancer procoagulant, has been found in all examined tissues as well as in blood serum of cancer patients. CP activity in homogenates of colon cancer tissues as well as in blood serum of the examined cancer patients has been markedly higher than in the normal subjects. These data indicate that CP activity in the neoplastic tissue homogenates and in blood serum may be of value in the diagnosis of cancer.
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PMID:[Diagnostic significance of cancer procoagulant activity in colorectal cancer]. 1087 Apr 14

The paper reviews the current studies on mechanism of thrombo-embolic complications in patients with malignancy. The neoplastic cells can express procoagulants like tissue factor (TF), cancer procoagulant (CP) and others, which induce thrombin formation in blood plasma and cause thrombo-embolic events, disseminated intravascular coagulation and other complications. Both procoagulants are acting via extrinsic pathway--TF makes complexes with factor VII and calcium ions, while CP acts directly on factor X transforming it into active form (Xa). Gynecological tumor-related complications occur in 20-30% patients with ovarian or uterine cancer.
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PMID:[Expression of thrombogenic substances by neoplasms: TF and cancer procoagulant. Pathogenic effects]. 1114 39

Tumor cells produce tissue factor, cancer procoagulant, plasminogen activators and other factors that interact with the coagulation system, the fibrinolytic system and vascular or blood cells such that they can upset the normal homeostasis and balance between activation and inhibition of the coagulation and fibrinolytic systems. These activities play a role in tumor cell growth and metastasis, vascular wall function, and hemostasis. Proteases and their inhibitors are intimately involved in all aspects of the hemostatic, cell proliferation and cellular signalling systems. This review provides a brief examination of recent observations in this complex interaction of cellular and hemostatic factors.
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PMID:Update on tumor cell procoagulant factors. 1154 74


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