Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0006142 (breast cancer)
 160,383 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Nearly all patients with cancer manifest laboratory evidence of hypercoagulability and some develop clinical thromboembolic disease (TED). Routine laboratory studies of blood coagulation have been performed in several large, prospective trials of the use of anticoagulant drugs in cancer treatment. The results of these studies, as well as data from several smaller studies of more sensitive tests of hypercoagulability [e.g. fibrinopeptide A (FPA); thrombin-antithrombin (TAT) complexes; prothrombin fragment F1 + 2)], indicate that the levels of some clotting proteins parallel disease activity. However, no studies of sound methodologic design have yet been performed to indicate that any of these tests of blood coagulation can serve as adequate predictors of TED in patients with cancer. In addition to the important role played by tumor-related procoagulants, several other mechanisms may be involved in the pathogenesis of thromboembolic events in patients with cancer, including stasis and endothelial damage. Considerable variability in the relative importance of these mechanisms in the pathogenesis of TED may exist among patients with different types of cancer. The risk for TED associated with surgical procedures in cancer patients is substantial and prophylactic antithrombotic therapy should be considered for most of these patients. Chemotherapy and hormonal therapy of cancer probably increases the likelihood of TED, particularly in those subjects with indwelling venous catheters. This risk has been particularly well-studied in patients with breast cancer treated with tamoxifen plus cytotoxic drugs. The pathogenic mechanisms may be complex but vascular injury is likely as a proximate cause of venous access catheter thrombosis and can be prevented with low dose coumadin therapy. The utility of low dose coumadin anticoagulation in reducing the risk for TED during breast cancer treatment is unknown but is currently being tested in a large, multiinstitutional study. Since chronic coumadin anticoagulation of cancer patients, and single pulse dose heparin prior to intravenous chemotherapy, both prevent thrombin generation, these agents may be of use in reducing the risk of chemotherapy-associated thrombosis. Prophylactic anticoagulation should be considered for high risk patients.
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PMID:Hemostatic alterations in cancer patients. 142 16

Recent progress in elucidating the complex and heterogeneous interactions between malignancy and coagulation or fibrinolysis reactions in humans has clarified the pathogenesis of disseminated intravascular coagulation that occurs with malignancy and has revealed evidence for two distinct pathways of growth regulation based on production by tumor cells of initiators of thrombin formation versus plasminogen activators. We have proposed a preliminary classification of tumors (see Table 2) based on these interactions. Type I tumors are those in which the tumor cells are associated with an intact coagulation pathway that leads to thrombin formation at the tumor periphery but in which the tumor cells lack u-PA. Examples of tumors in this category include SCCL, malignant melanoma, and renal cell carcinoma. Type II tumors are those in which the tumor cells express u-PA but lack an associated coagulation pathway leading to thrombin formation. Examples of type II tumors include prostate cancer, colon cancer, breast cancer, and N-SCLC. Type III tumors are those that express neither of these pathways, or exhibit some other pattern of interaction. Obviously, this formulation must be regarded as hypothetical. However, this concept fits with the limited data available to date from clinical trials. More importantly, this hypothesis can be tested further by means of intervention aimed at interrupting pathways relevant to specific tumor types. Characterization of additional tumor types by the methods described should permit amplification of this classification of tumors and other patterns of interaction may be defined. Exploration of the coagulation-cancer interaction holds considerable promise for gaining new understanding of both the coagulation mechanism and tumor biology. Most intriguing is the prospect that imaginative approaches to cancer treatment may be devised that are not only relatively nontoxic and low cost, but also effective.
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PMID:Pathways of coagulation/fibrinolysis activation in malignancy. 157 11

The occurrence and distribution of components of coagulation pathways in situ were determined using immunohistochemical techniques applied to 10 cases of primary carcinoma of the breast, normal breast tissue obtained from two patients undergoing reductive mammoplasty, and three patients with benign breast tumors. Tumor cells stained for factor X and thrombomodulin but not for tissue factor, factor V, factor VII, or factor XIII. Rare nonneoplastic duct epithelial cells stained for thrombomodulin, but these tissues did not otherwise stain for any of these antigens. Macrophages within the tumor stroma stained for tissue factor, factor VII, and factor XIII but not for factor V or factor X. These features of macrophages were the same in malignant and nonmalignant breast tissue. Fibrinogen was present in abundance throughout the connective tissue in breast cancer but not in nonmalignant tissues. By contrast, no staining was observed using fibrin-specific antibodies. These results suggest that an intact coagulation pathway does not exist in breast cancer tissue and that thrombin capable of transforming fibrinogen to fibrin is not generated in significant amounts in this tumor type. While fibrin is not a feature of the connective tissue stroma in breast cancer, it is conceivable that the abundant fibrinogen present in the tumor connective tissue (and factor XIII present in connective tissue macrophages) might contribute to the structural integrity of breast tumor tissues.
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PMID:Fibrinogen deposition without thrombin generation in primary human breast cancer tissue. 167 Sep 92

Tumor cell invasion and metastasis is a multifactorial process, which at each step may require the action of proteolytic enzymes such as collagenases, cathepsins, plasmin, or plasminogen activators. An enzymatically inactive proenzyme form of the urokinase-type plasminogen activator (pro-uPA) is secreted by tumor cells which may be converted to an enzymatically active two-chain uPA-molecule (HMW-uPA) by plasmin-like enzymes. Action of proteases on pro-uPA may generate the enzymatically active or inactive high-molecular-weight form of uPA (HMW-uPA). Some proteases (plasmin, cathepsin B and L, kallikrein, trypsin or thermolysin) activate pro-uPA by cleaving the peptide bond Lys158 and IIe159. Other proteases (elastase, thrombin) cleave pro-uPA at different positions to yield enzymatically inactive HMW-uPA. HMW-uPA may be split into the enzymatically active LMW-uPA and the enzymatically inactive ATF (amino terminal fragment). ATF may be cleaved between peptide sequence 20 and 40 within the receptor binding domain of uPA (GFD). Such impaired ATF does not bind to uPA-receptors. Action of the bacterial endoproteinase Asp-N from Pseudomonas fragi mutant on pro-uPA or HMW-uPA, however, generates intact ATF which efficiently competes for binding of HMW-uPA or pro-uPA to receptors on tumor cells. High uPA-antigen content (pro-uPA, HMW-uPA, or LMW-uPA) in breast cancer tissue (not in plasma) indicates an elevated risk for the patient of recurrences and shorter overall survival. Thus pro-uPA/uPA-antigen content in breast cancer tissue serves as an independent prognostic parameter for the outcome of the disease. Cathepsin D is also an independent prognostic factor for recurrences and overall survival. High content of cathepsin D in breast cancer tumors is, however, not correlated with elevated levels of pro-uPA/uPA indicating that synthesis and release of cathepsin D and pro-uPA/uPA are independent events.
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PMID:Biological and clinical relevance of the urokinase-type plasminogen activator (uPA) in breast cancer. 180 51

Plasma levels of D-dimer, a degradation product of crosslinked fibrin, were determined in 73 patients with breast cancer. In these patients, significantly elevated plasma levels of D-dimer were found, as compared to healthy controls (P less than 0.0001). In addition, we observed a moderate correlation between plasma levels of D-dimer and those of CA15-3 (r = 0.40; P less than 0.001) and between D-dimer and carcinoembryonic antigen (r = 0.39; P less than 0.01). Plasma levels of thrombin-antithrombin III complex (TAT), reflecting the activation of thrombin, were also significantly elevated in patients with breast cancer (P less than 0.0001), and a poor, but significant correlation between carcinoembryonic antigen and TAT (r = 0.25; P less than 0.05) was found. We concluded that the increase in plasma D-dimer and TAT levels might reflect an enhanced activation of the clotting system in patients with breast cancer.
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PMID:Plasma levels of D-dimer: a crosslinked fibrin-degradation product in female breast cancer. 203 94

Platelets contain mitogenic activities for MCF-7 human breast cancer cells when assayed under serum-free chemically defined conditions. Purification from outdated human platelets identified insulinlike growth factor I (IGF-I) as the most potent breast cancer cell mitogen in lysates (Karey KP, Sirbasku DA: see accompanying article, this issue). In this study the release and subcellular localization of IGF-I was investigated. Degranulation of platelets by thrombin treatment caused release of lysosomal enzymes (beta-glucuronidase and N-acetyl-D-glucosaminidase), alpha-granule proteins (beta-thromboglobulin and fibrinogen) as well as mitogenic activity for MCF-7 cells and IGF-I as measured by radioimmunoassay (RIA) and radioreceptor assay. Release of mitogenic activity and immunologically identified IGF-I was induced tenfold over controls by thrombin and was nearly complete as compared to platelets disrupted by repeated freezing and thawing. Disruption of platelets by nitrogen cavitation followed by separation of the organelles by sucrose density gradient sedimentation showed that IGF-I and mitogenic activity localized predominantly to fractions containing alpha-granules rather than soluble cellular components, lysosomes, or dense granules. The morphology of MCF-7 cells in serum-free medium supplemented with supernatants from thrombin-treated platelets also indicated the release of important cell-adhesion factors for human breast cancer cells.
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PMID:Human platelet-derived mitogens. II. Subcellular localization of insulinlike growth factor I to the alpha-granule and release in response to thrombin. 275 54

A multicenter, randomized, controlled trial was conducted comparing active treatment with placebo in 227 patients with breast, colorectal, lung and other solid forms of cancer. Combination therapy, (CT) conventionally employed for the various types of tumor involved, was associated with MPA (117 patients) or placebo (110 patients). MPA was given orally as tablets, as a dose of 500 mg b.i.d. for 6 months. The results were, briefly, as follows: The incidence of leukopenia was significantly lower in the groups receiving MPA in patients with breast and colorectal cancer (P less than 0.02). Tumors of the lung and other solid forms showed no such difference. The incidence of thrombocytopenia was the same in all disease groups. Objective responses (CR + PR) were observed in 23/46 (50%) of breast cancer patients treated with CT + MPA, and in 13/47 (28%) of those given CT + placebo. The difference was significant (P less than 0.02). Subjective parameters also showed more improvement in the MPA group than in the patients given CT alone. No significant differences were found for the other types of tumor, but the numbers in this population were very limited. In a group of 45 patients, antithrombin III a (%), antithrombin III R: Ag (%), plasminogen (mg/dl), alpha-2 macroglobulin (%), factor VIII C (%), factor VIII R: Ag (%) and factor IX C (%) were determined. The most interesting post-treatment findings were an increase in anti-thrombin III (activity and antigen level) and in plasminogen. This suggests that MPA does not increase the risk of thrombosis, and might even, to some extent, impede tumor-induced thrombophilia.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Protective effect of high-dose medroxyprogesterone acetate (HD-MPA) on hematological toxicity induced by chemotherapy for advanced solid tumors: a multicentric controlled clinical trial. MPA-Hematology Italian Cooperative Group. 287 45

An increased incidence of thromboembolic complications occurring in cancer patients during chemotherapy was recently reported. In view of this report, a study in 49 patients receiving adjuvant chemotherapy for Stage II breast cancer was begun in order to determine the effect of antineoplastic drugs on coagulation factors and platelet function. Among the coagulation factors, a significant decrease of thrombin time and partial prothrombin time was observed, whereas platelet function tests were unchanged. This finding suggests a trend towards hypercoagulability induced by chemotherapy. This effect should be considered when chemotherapy is employed in advanced cancer patients at high risk for thrombosis.
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PMID:Hypercoagulable state induced by cytostatic drugs in stage II breast cancer patients. 373 Oct 37

In order to bring about ideal chemotherapy, targeting, topical maintenance, sustained release and no side effects of the anticancer agent are essential. Adriamycin (ADM) was immobilized on absorbable gelatin material (G) together with thrombin (T) and factor XIII (XIII) to form such an agent, "G . T . XIII-ADM". The material was applied as an embolic agent in experimental transcatheter arterial chemo-embolization (TACE) in rabbits with VX2-carcinoma. Response rate of the tumor (CR + PR) was 75% for "G . T . XIII-ADM", and 28.6% for intra-arterial infusion (IA) of ADM. The ADM was maintained for a long period both in the tumors and the metastatic lymph nodes, in the animals given the chemo-embolic agent. The materials were then clinically prescribed as an embolic agent in preoperative TACE for patients with locally advanced breast cancer. The oncolytic effects obtained with the "G . T . XIII-ADM" were remarkably favorable and the side effects were almost nil. These positive data suggest that "G . T . XIII-ADM" has great potential as a new approach to cancer chemotherapy.
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PMID:[A newly devised chemo-embolic agent, G. T. XIII-ADM]. 405 9

Anticancer agents, Mitomycin C and Adriamycin, were immobilized on absorbable gelatin materials, respectively with a blood clotting factor, Factor XIII and thrombin with a special technique we have developed. The materials were clinically applied as thrombotic agent in pre-operative therapeutic transcatheter arterial embolization (TAE) to 5 patients with locally advanced breast cancer. About 1 week after TAE, the regression of the primary tumor was found in 4 out of 5 patients; all patients received currative operation without any trouble. The histological examinations of the excised specimens showed remarkable degenerative changes (IIA and IIB: Shimosato's classification) of cancer cells not only in the primary tumor, but also in the metastatic regional lymph node. No complications due to the TAE were observed. These findings strongly suggest that this newly deviced materials are quite effective in pre-operative treatment for the locally advanced breast cancers.
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PMID:[Pre-operative transcatheter arterial embolization for the patients with locally advanced breast cancers--a newly deviced thrombotic material]. 641 Sep 96


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