Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0178874 (tumor progression)
 40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A volume of data that has accumulated for over a century has suggested that fibrin may facilitate the persistence and progression of malignancy. Techniques that have been developed recently have shown that fibrin is indeed a component of the connective tissue stroma in human malignancy but in only a few tumor types. However, therapeutic intervention studies with drugs that limit thrombin activity or enhance fibrinolysis have shown favorable clinical effects in at least one such tumor type. These favorable findings affirm the concept that cause-and-effect relationships do, in fact, exist between thrombin generation with fibrin formation and tumor progression, and suggest that a rational basis exists for the design of future drug intervention trials that target reactions relevant to specific tumor types. These findings also provide a basis for the design of experiments capable of defining further the role of fibrin in the integrity of these tumor types. Because fibrinogen is found much more commonly than fibrin in the connective tissue of a variety of human malignancies, attention might reassumably be directed to determining the possible contribution of this molecule as well as of fibrin to tumor progression.
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PMID:The role of fibrin in tumor metastasis. 142 19

In patients with malignant tumors a high incidence of haemostatic disorders occurs. The reaction of thrombin with its major inhibitor antithrombin III (AT III) leads to the formation of a stable complex, which represents a sensitive marker for the activation of intravascular coagulation. In 153 patients suffering from different kinds of gynaecological malignancy thrombin-antithrombin III-complex (TAT) levels were measured. In 21 cases the course of the disease was studied. Of 153 patients with gynaecological malignancy 102 (67%) showed TAT plasma concentrations above the normal range before therapy. Seven patients with elevated TAT levels before treatment showed a decrease of TAT concentrations to the normal range when no evidence of disease was obvious. In 5 cases TAT levels were in the normal range before and after successful therapy, 4 patients with tumor progression and 5 patients with tumor recurrence showed an increase of TAT levels. The TAT plasma concentrations correlated with the presence or absence of the tumor. Measurement of TAT plasma concentrations in gynaecologic malignancies can detect any thromboembolic risk for the patient and in addition can reveal information about the course of the disease.
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PMID:Elevated thrombin-antithrombin III complex concentrations in patients with gynaecological malignancy. 201 73

Studies of malignancy in experimental animal models have indicated that cause-effect relationships exist between coagulation activation and cancer progression. Evidence for coagulation activation in human malignancy together with favorable results from pilot clinical trials led to the establishment of a prospective, randomized therapeutic trial of warfarin in cancer. A statistically significant prolongation of survival was observed in patients with small cell carcinoma of the lung entered into this study. Demonstration of an initiator of coagulation activation together with coagulation factor intermediates and fibrin in situ associated with viable tumor cells in small cell carcinoma of the lung is consistent with the hypothesis that tumor-initiated thrombin formation might contribute to progression of this tumor type. These observations suggest novel experimental treatment strategies for small cell carcinoma of the lung. Warfarin anticoagulation may be of value in the treatment of certain other types of malignancy.
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PMID:Small cell carcinoma of the lung: interaction with the blood coagulation mechanism and treatment with anticoagulants. 282 1

Acquired dysfibrinogenemia has not been previously reported as a paraneoplastic marker for malignancy. This report describes the clinical course of a patient who at the time of diagnosis of nonmetastatic renal cell carcinoma had dysfibrinogenemia characterized by prolongation of the thrombin and Reptilase times and increased sialic acid content of the purified fibrinogen. The thrombin and Reptilase times returned toward normal values after nephrectomy but became abnormal with the development of nonhepatic metastases. It is concluded that acquired dysfibrinogenemia can be part of a paraneoplastic syndrome and is a sensitive plasma marker for tumor progression.
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PMID:Acquired dysfibrinogenemia. Paraneoplastic syndrome in renal cell carcinoma. 398 42

Adhesive interactions between cells and the subendothelial extracellular matrix take place at several stages during tumor progression and metastasis. We have previously demonstrated that thrombin possesses an active yet cryptic Arg-Gly-Asp (RGD) site which can be exposed in the presence of low concentrations of plasmin and cell-associated heparan sulfate proteoglycan. Thus, thrombin may act as a matrix-adhesive molecule via activation of the alpha v beta 3 integrin. We have now identified a 31 amino acid fragment as the minimal thrombin-generated cleavage product, which contains an active RGD site, following gel filtration analysis on FPLC Superdex 75 column. The role of membrane-associated heparan sulfate in thrombin conversion to an adhesive protein was demonstrated by using CHO cell mutants defective in various aspects of glycosaminoglycan synthesis. Incubation of both thrombin and a low concentration of plasmin on the surface of wild type CHO cells resulted in a typical digestion cleavage profile upon gel filtration. No cleavage products were observed when thrombin and a suboptimal plasmin concentration were incubated on monolayers of CHO cell mutants lacking heparan sulfate. Next, we examined the possible role of the thrombin RGD site during the progression of tumor development and metastasis. Toward this, we tested murine melanoma cells expressing low (B16-F1 cells) and high (B16-BL6 cells) lung colonization potentials in cell adhesion assays in vitro. Differential adherence capability of the cells was observed: while high attachment levels of B16-BL6 cells were obtained, the low metastatic B16-F1 cells did not adhere to thrombin RGD. Antibodies raised against the RGD site in thrombin specifically recognized thrombin digested with plasmin, but were unable to interact with native thrombin or prothrombin and inhibited potently B16-BL6 melanoma cell adhesion. Furthermore, the antibodies failed to recognize RGD in other adhesive plasma proteins such as vitronectin, fibrinogen, or fibronectin. Provided that the RGD-containing fragments of thrombin are widely distributed throughout the vascular system, they may have a significant role during tumor progression and dislodgement of metastatic cells. The development of RGD mimetics and/or specific antibodies might thus be applied to inhibit a critical step in metastatic spread.
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PMID:The involvement of thrombin RGD in metastasis: characterization of a cryptic adhesive site. 774

Osteopontin (OPN), a secreted phosphoprotein, has been implicated in various biological phenomena (e.g. bone development, sepsis, tumor progression, and metastasis). Its role in any context is poorly understood. OPN contains a conserved Gly-Arg-Gly-Asp-Ser (GRGDS) sequence, and binds to cells via integrin-mediated mechanisms. Using recombinant human osteopontin-glutathione S-transferase fusion protein and our improved hybridoma fusion partner (Sp2/mIL6), we raised murine monoclonal antibodies against osteopontin. We characterized two antibodies that recognize not only recombinant but also native human osteopontin. These antibodies do not cross-react with mouse osteopontin (recombinant protein or that secreted by ras-transformed NIH 3T3 cells), or bovine bone osteopontin, suggesting that they recognize epitopes unique to human OPN. One antibody specifically inhibited adhesion of MDA-MB-435 human breast cancer cells and ras-transformed NIH 3T3 cells to human osteopontin. This antibody failed to recognize osteopontin cleaved by thrombin, which cleaves adjacent to the cell binding domain. We previously showed that thrombin cleavage reduces osteopontin cell binding activity. Thus we postulate that this monoclonal antibody recognizes and interferes with the function of the RGD/thrombin cleavage region of human OPN.
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PMID:Inhibition of Arg-Gly-Asp (RGD)-mediated cell adhesion to osteopontin by a monoclonal antibody against osteopontin. 808 34

To clarify the significance of factors of coagulation and fibrinolysis in tumor progression, we measured levels of D-Dimer, Thrombin-Anti-Thrombin III complex (TAT), and Plasmin-alpha 2-Anti-Plasmin complex (PAP) in 55 patients with primary lung cancer, and studied the relationship between these parameters and clinical TNM stage. D-Dimer, TAT and PAP increased in parallel with progression of primary tumor and distant metastasis, whereas there was no significant relationship between the progression of nodal involvement and these factors. In 19 patients, we investigated changes of D-Dimer, PAP and TAT during chemotherapy. These parameters decreased in the partial response group and minor response group, whereas they increased in the progressive disease group. These data suggest that D-Dimer, PAP and TAT determination is useful for evaluation of disorders of coagulation and fibrinolysis related to tumor progression or remission in patients with lung cancer.
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PMID:[Significance of factors of coagulation and fibrinolysis in progression of lung cancer]. 839 May 88

In this article, the "tethered ligand" thrombin receptor was identified on human pancreatic tumor cells, MIA PaCa-2, using immunofluorescence studies with a monoclonal anti-thrombin receptor antibody. Pharmacological characterization, using 3H-labeled thrombin receptor activating peptide-6 (TRAP-6) as radioligand, demonstrated a single class of high-affinity binding sites (KD = 9.1+/-1.8 x 10(-7) M) and a binding capacity of 13.9+/-0.7 fmol/mg protein. These binding sites represent functional thrombin receptors, as shown by alpha-thrombin- and TRAP-6-induced mobilization of free intracellular calcium, protein kinase C translocation from cytosol to the cell membrane, and stimulation of DNA synthesis in MIA PaCa-2 cells. These results provide the first identification of tethered ligand thrombin receptor in human pancreatic cancer cells and suggest thrombin receptor involvement in mechanisms of human pancreatic tumor progression.
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PMID:Characterization of functional thrombin receptors in human pancreatic tumor cells (MIA PACA-2). 951 Jan 43

Aggregation of host platelets by circulating tumor cells is believed to play an important role in the metastatic process. Because thrombomodulin (TM) is one of the major mediators of the activation of the anticoagulant protein C by thrombin, we examined 136 primary tumor tissues and 45 metastatic lymph node tissues of lung squamous cell carcinomas for TM expression using immunohistochemical methods. The number of tumors with positive TM staining was less in metastatic tumors (44%) than in primary tumors (74%) (P < 0.01). Of various clinicopathological factors, better differentiation and lower N stage were significantly associated with TM expression. A loss of TM expression was associated with a shortened survival in 113 patients who underwent complete resection of the lung tumor (P < 0.01). In this group, TM expression and tumor-node-metastasis staging were independent significant determinants for survival, determined using Cox's multivariate survival analysis. Since TM is apparently associated with tumor progression and differentiation, this correlation may serve as a prognostic indicator in squamous cell carcinoma of the lung.
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PMID:Prognostic value and clinicopathological correlation of thrombomodulin in squamous cell carcinoma of the human lung. 981 28

Extravascular fibrin deposition is frequently observed within and around neoplastic tissue and has been implicated in various aspects of tumor growth. The distribution of fibrin deposits was investigated in squamous cell carcinomas representing different stages of tumor progression of the larynx (n = 25) and hypopharynx (n = 9) by immunofluorescent techniques. Double and treble labelings were used to detect fibrinogen and fibrin in combination with marker antigens for tumor cells (cytokeratin), endothelial cells (von Willebrand factor), macrophages (recognized by KiM7), as well as factor XIII subunit A (FXIIIA) and tenascin (an embryonic extracellular matrix protein newly expressed during tumorigenesis). All tissue samples showed specific staining for fibrinogen/fibrin. Fibrin deposition was localized almost exclusively in the connective tissue compartment of tumors with characteristic accumulation at the interface of connective tissue and the tumorous parenchyma. In certain tumor samples showing highly invasive characteristics, fibrin deposits were observed in close association with tumor blood vessels in the tumor cell nodules. The overlapping reactions with polyclonal antibody to fibrinogen/fibrin and monoclonal antibody to fibrin indicate the activation of the coagulation cascade resulting in in situ thrombin activation and fibrin formation. Fibrin was crosslinked and stabilized by FXIIIA as revealed by urea insolubility test. Accumulation of phagocytozing macrophages detected by Ki M7 monoclonal antibody could be seen in areas of fibrin deposition. The blood coagulation factor XIIIA was detected in and around the cells labeled with Ki M7 antibody. Tenascin and fibrin deposits were found in the same localization in the tumor stroma and in association with tumor blood vessels within the tumor cell nodules. Neither fibrin nor tenascin were detected in the histologically normal tissue adjacent to tumors. The close association between fibrin deposits and macrophage accumulation strongly suggests the active participation of tumor-associated macrophages in the formation of stabilized intratumoral fibrin that facilitates tumor matrix generation and tumor angiogenesis.
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PMID:Fibrin deposition in squamous cell carcinomas of the larynx and hypopharynx. 984 69


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