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)

Transforming growth factor (TGF)-alpha is a pleiotropic polypeptide which mediates a variety of tissue-specific cellular responses such as induction of proliferation, cell migration, vascularization, and formation of extracellular matrix. TGF-alpha is produced by certain tumor cells and embryogenic tissues, as well as by normal cells of different origin. Within the granulocytic lineage, TGF-alpha production has been shown in promyelocytic leukemia cells induced to differentiate, as well as in blood eosinophils of patients with the idiopathic hypereosinophilic syndrome. The present study was carried out in order to examine expression of the TGF-alpha gene in polymorphonuclear (PMN) and mononuclear (MN) blood cells of normal healthy donors. While MN and neutrophilic PMN failed to synthesize TGF-alpha transcripts and protein, eosinophils constitutively exhibited TGF-alpha transcripts accompanied by the release of immunoreactive TGF-alpha protein. Exposure of PMN and MN cells to the leukocyte-activating cytokines interleukin (IL)-3, IL-5, and granulocyte-macrophage colony-stimulating factor resulted in a several-fold increase of TGF-alpha mRNA expression and protein release by eosinophils, but not by neutrophils and MN cells. PMN and MN were insensitive to induction of TGF-alpha release by IL-8 and granulocyte colony-stimulating factor. These results point to a functional role of eosinophils in disorders characterized by unbalanced TGF-alpha production such as disease states associated with abnormal matrix formation and neovascularization which may be explained by the present demonstration of TGF-alpha production in these cells.
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PMID:Expression of the transforming growth factor-alpha gene by human eosinophils is regulated by interleukin-3, interleukin-5, and granulocyte-macrophage colony-stimulating factor. 812 34

Induction of IL-8 gene expression was investigated in IL-2-stimulated circulating peripheral blood polymorphonuclear neutrophils (PMN). Brief exposure of normal PMN to human rIL-2 enhanced both transcriptional and translational expression of IL-8. The IL-8 mRNA was first detectable by 3 h, followed by a continuous maintenance of high mRNA levels up to 18 h. Maximal transcription was obtained with 1000 U/ml of IL-2, which achieved the level observed with known neutrophil-activating factors such as granulocyte macrophage-CSF and Candida albicans. The protein synthesis inhibitor, cycloheximide, had no detectable effect on levels of IL-8 mRNA expression in PMN incubated in medium alone; however, cycloheximide could selectively modulate IL-8 mRNA transcription in PMN, depending on the cytokine used. Cycloheximide did not affect or alter IL-8 mRNA induction in IL-2-treated PMN but abrogated it in granulocyte macrophage-CSF-treated PMN and super-induced the level of IL-8 mRNA in C. albicans-treated PMN. Of significance was the observation that IL-2 has no direct chemotactic effect on PMN, whereas the cell-free supernatants from IL-2-stimulated PMN show potent chemotaxis for freshly isolated PMN, which can be specifically blocked by anti-IL-8 Abs. These findings suggested that the induction of IL-8 gene expression in PMN by IL-2 may be involved in the recruitment of PMN into tissues during local IL-2 therapy in human cancer and in part contribute to tumor rejection.
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PMID:Induction of IL-8 gene expression in human polymorphonuclear neutrophils by recombinant IL-2. 814 38

The inflammatory mechanisms which take place in microcrystalline arthropathies can be divided into several stages, each of them being characterized by the activation of a set of mediators. The process begins with activation by crystals of resident cells in the synovial fluid which release various pro-inflammatory factors including several cytokines. Among these, interleukin 1 (IL-1) and tumor-necrosis factor alpha (TNF-alpha) have multiple effects and play a predominant role in the starting of inflammation. With the contribution of humoral factors, also activated by the crystals, IL-1 and TNF-alpha activate notably the endothelial cells to allow leucocyte extravasation. The attraction and massive activation of polymorphonuclear neutrophils (PMNs) which then occurs and characterizes acute microcrystalline arthropathies mainly depend on IL-8, another cytokine secreted by synoviocytes. At the same time, an acute phase systemic reaction principally induced by IL-6 develops. When inflammation is prolonged mechanisms of tissue destruction begin to act, notably by releasing proteases induced by IL-1 and TNF-alpha. These mechanisms are counterbalanced by release of antiproteases, notably those induced by the transforming growth factor beta (TGF-beta) and by IL-6. Finally, these inflammatory processes may limit themselves or even stop spontaneously, due to a series of control mechanisms including cytokines with anti-inflammatory effects, ACTH release and physico-chemical changes in crystals.
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PMID:[Mechanisms of microcrystalline inflammation]. 817 68

Virtually pure primary cultures of normal mammary epithelial cells (MEC) obtained from healthy women were shown to release interleukin 6 and 8 (IL6, IL8) and to produce a nonsecreted form of tumor-necrosis factor (TNF). No interferon (IFN), whether alpha, beta, or gamma, or IL1-alpha or -beta could be detected. Analysis of cellular RNA confirmed these findings and showed that MEC also express IL6 receptor and TNF-alpha-related mRNAs. Epithelial cells were selectively stained by antibodies to IL6, IL8 and TNF-alpha both in primary cultures and in the normal mammary gland. Samples of human milk contained sizable amounts of IL6, IL8 and IFN-gamma; yet the liquid phase was consistently negative for other cytokines (i.e., TNF-alpha, IFN-alpha/-beta, IL1-alpha/-beta). Expression of IL6 (but not of IL8 and TNF-alpha) was abolished in ductal infiltrating carcinomas and greatly reduced in cultures of oncogene-transfected mammary cells, suggesting that alterations of IL6 expression are associated with pathogenesis in breast cancer.
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PMID:Normal breast epithelial cells produce interleukins 6 and 8 together with tumor-necrosis factor: defective IL6 expression in mammary carcinoma. 825 29

Monocyte chemotactic and activating factor (MCAF) is an important mediator of monocyte recruitment to sites of chronic inflammation and neoplasia. In the present study, we determined whether MCAF can also enhance the activation of tumoricidal capacity of monocytes. Human monocytes incubated with MCAF and subthreshold concentrations of lipopolysaccharide (LPS) exhibited synergistic tumoricidal activity against allogeneic A375 melanoma cells, irrespective of their metastatic potential. The sequence of MCAF and LPS treatment was crucial. Monocytes treated first with MCAF for 4 h and then with LPS for 18 h were highly cytotoxic to the melanoma cells, whereas monocytes first treated with LPS and then with MCAF were not. Treatment of monocytes with MCAF and LPS also significantly increased production of tumor necrosis factor. These data suggest that like interferon-gamma, MCAF can prime human monocytes to respond to LPS. Interleukin-8, a chemokine for neutrophils, did not enhance the monocytes' LPS-triggered tumoricidal response. Collectively, these data show that MCAF can influence the recruitment and tumoricidal activation of blood monocytes. Therefore, MCAF may be an important mediator of tumor regression.
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PMID:Synergism between human recombinant monocyte chemotactic and activating factor and lipopolysaccharide for activation of antitumor properties in human blood monocytes. 826 May 37

A number of different cytokines, including IL-1 alpha and beta, IL-2, IL-3, IL-4, IL-6, IL-7, IL-8, IFN-alpha, -beta and gamma, TNF-alpha -beta, and TGF-beta 1, can modulate the expression of distinct cell surface antigens of normal and neoplastic cells. Both induction/increase of expression and reduction of expression can be achieved depending on the antigen and on the cytokine. Antigens subjected to the modulating activity of cytokines include distinct families of cell surface structures such as the molecules coded by the major histocompatibility complex (MHC), the superfamily of adhesion receptors that regulate cell-cell and cell-matrix interaction, receptors for cytokines and growth factors and tumor-associated antigens. The modulating activity of cytokines is a consequence of their influence on gene expression, protein synthesis, membrane expression and shedding of antigens from the cell surface. The changes of phenotype due to the action of cytokines can influence the signalling pathways dependent on the expression and function of cell surface structures. Therefore, the antigen modulating activity of cytokines can thoroughly affect the biological behavior of normal and neoplastic cells. As described here, most of the modulating effects of cytokines on different cell surface structures and the functional consequences of antigenic modulation can be verified in human malignant melanoma cells.
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PMID:The role of cytokines in the modulation of cell surface antigens of human melanoma. 827 6

Liposome-encapsulated muramyl tripeptide phosphatidylethanolamine (L-MTP-PE), a new biologic response modifier, was designed to target the immunomodulator to monocytes and macrophages. Human monocytes/macrophages phagocytize L-MTP-PE, with subsequent upregulation of interleukin (IL)-1 alpha, IL-1 beta, IL-6, IL-8, tumor necrosis factor (TNF)-alpha, and monocyte chemotactic and activating factor genes and with the production and secretion of these cytokines in vitro. L-MTP-PE-activated macrophages kill tumor but not normal cells in vitro. Following i.v. infusion of L-MTP-PE into cancer patients, its uptake was demonstrated in liver, spleen, lung, and in and around metastases to lung. We also investigated whether L-MTP-PE therapy administered in a neoadjuvant setting could improve the disease-free interval in relapsed osteosarcoma patients with lung metastasis. Patients received either a 12- or 24-week course of L-MTP-PE after surgical removal of all metastases. Following L-MTP-PE infusion, induction of circulating TNF-alpha, IL-6, neopterin, and C-reactive protein was demonstrated. Disease-free intervals were calculated from the day of surgery to the day of relapse in each group and were compared with the disease-free interval for a historical control group. Those patients receiving 24 weeks of L-MTP-PE showed a significant (p < 0.03) prolongation in time to relapse. These data indicate that L-MTP-PE is an active agent against osteosarcoma and warrants further investigation in an adjuvant setting.
J Immunother Emphasis Tumor Immunol 1993 Nov
PMID:Liposome-encapsulated MTP-PE: a novel biologic agent for cancer therapy. 828 Jul 10

This review concentrates on growth autonomy of tumor cells in relation to tumor progression. Human malignant melanoma serves as an example for progressive growth factor independence at subsequent stages of tumor progression. Mechanisms by which malignant cells acquire growth factor independence are discussed. In melanoma, deregulation of growth regulatory pathways has been described on four levels: 1) aberrant production of autocrine growth factors that substitute for exogenous growth factors (basic fibroblast growth factor [bFGF]); 2) alterations in the response to negative autocrine growth factors (interleukin [IL]-6 and transforming growth factor [TGF]-beta); 3) overexpression of epidermal growth factor receptors (EGF-R); and 4) alterations of cellular protooncogenes involved in signal transduction (RAS, MYB) and growth suppression (p53). In addition to bFGF and IL-6, multiple other growth factor genes are activated in malignant melanoma cells but not normal melanocytes. These include both chains of platelet-derived growth factor (PDGF), TGF-alpha, IL-1, IL-8, and tumor necrosis factor (TNF)-alpha. Of these, PDGF-B has been investigated in more detail. Melanoma-derived PDGF clearly does not act in a direct autocrine mode, but has important paracrine effects on normal tissue constituents, notably fibroblasts and endothelial cells, that are essential for tumor development in vivo. It is speculated that other melanoma-derived growth factors with as yet undefined functions similarly exert such paracrine or 'indirect' autocrine effects that cannot be sufficiently addressed in studies on cultured cells.
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PMID:Growth factor independence and growth regulatory pathways in human melanoma development. 828 9

A novel Hodgkin cell line, designated HD-MyZ, was established from the pleural effusion of a 29-yr-old patient with Hodgkin's disease (HD) of nodular sclerosing type. The majority of cells grow adherently and display typical morphological characteristics of Reed-Sternberg (RS) and Hodgkin (H) cells, i.e., large multi- and mononucleated cells with prominent nucleoli. Immunofluorescence analysis revealed a myelomonocytoid immunophenotype (expression of CD13 and CD68, and lack of lymphoid markers). HD-MyZ cells strongly expressed restin, a recently described intermediate filament-associated protein, the expression of which is restricted to H cells, RS cells, and in vitro cultivated peripheral blood monocytes. In addition mRNA expression of c-fms (colony-stimulating factor 1 receptor) could be induced in HD-MyZ cells by phorbol myristate acetate (PMA) stimulation. Southern blot analysis did not detect rearrangement of T cell receptor beta and immunoglobulin H loci, thus demonstrating the lack of lymphoid commitment. HD-MyZ cells were also devoid of Epstein-Barr virus genomes. HD-MyZ cells constitutively express mRNAs for interleukin 1 alpha (IL-1 alpha), IL-1 beta, IL-5, IL-6, IL-7, IL-8, IL-10, IL-1 receptor (type I), and IL-6 receptor. Stimulation of cells with PMA increased mRNA expression as well as the secretion of IL-1 beta, IL-6, and IL-8, and induced the de novo expression of IL-8 receptors. Xenotransplantation into severe combined immunodeficient (SCID) mice by intravenous or subcutaneous inoculation led to development of disseminated tumors with infiltrative and destructive growth. In addition lymphadenopathy, pleural effusion, and infiltration of spleen were observed. Morphological and immunological analysis of tumor cells revealed the same features as HD-MyZ cells. This cell line might be an important tool for understanding the pathogenesis and biology of HD. In addition the SCID mice model might prove helpful in developing new therapeutic strategies.
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PMID:Characterization of a novel Hodgkin cell line, HD-MyZ, with myelomonocytic features mimicking Hodgkin's disease in severe combined immunodeficient mice. 838 41

Tumor cells are capable of simultaneously producing a number of related inflammatory peptides, now classified as chemokines. We have isolated a new human granulocyte chemotactic protein (GCP-2), coproduced with interleukin-8 (GCP-1/IL-8) by osteosarcoma cells. Furthermore, the bovine homologue of human GCP-2 was purified from kidney tumor cells using the same isolation procedure. Both chemokines occur in at least four NH2-terminally truncated forms. These 5-6 kDa proteins do not differ in potency and efficacy as granulocyte chemotactic factors using a standard in vitro migration assay. The complete primary structures of human and bovine GCP-2 were disclosed by sequencing peptide fragments derived from the natural proteins. On the basis of the conservation of four cysteine residues, the two molecules are to be classified within the C-X-C chemokine family, including IL-8. Human and bovine GCP-2 are 67% similar at the amino acid level. Their sequences show only weak similarity with that of IL-8, and human GCP-2 does not cross-react in a radioimmunoassay for IL-8. Human and bovine GCP-2 are specific granulocyte chemotactic factors in that they do not attract human monocytes. Bovine GCP-2 is not species specific since it is at least as active as human GCP-2 on human granulocytes. Both chemokines can also activate postreceptor mechanisms leading to release of gelatinase B by granulocytes. This is indicative for a possible role in inflammation and tumor cell invasion.
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PMID:Human and bovine granulocyte chemotactic protein-2: complete amino acid sequence and functional characterization as chemokines. 839 43


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