Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029463 (osteosarcoma)
 16,637 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have examined the correlation between matrix metalloproteinase (MMP) expression and metastatic properties of a low metastatic osteosarcoma cell line, osteosarcoma takase (OST), under stimulation by tumour necrosis factor alpha (TNF alpha). In vivo, OST cells exhibited significantly increased colonization in the lungs of nude mice in a dose-dependent manner when they were treated by TNF alpha prior to injection. In vitro, TNF alpha enhanced tumour cell invasion through the reconstituted basement membrane in a transwell chamber up to 2.5-fold. Gelatin zymography and sandwich enzyme immunoassays demonstrated marked production of MMP-9 [92-kDa gelatinase/type IV collagenase (gelatinase B)] but not MMP-2 [72-kDa gelatinase/type IV collagenase (gelatinase A)], MMP-3 (stromelysin-1) or MMP-7 (matrilysin). Motility of the tumour cells and adhesion to cultured endothelial cells were slightly increased by the TNF alpha treatment up to 1.6-fold and 1.4-fold, respectively, while the growth rate was decreased. These results suggest that upregulation of MMP-9 together with enhanced motility and endothelial adhesion contribute to the increased metastatic ability of OST cells induced by TNF alpha treatment.
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PMID:Expression of matrix metalloproteinase 9 (92-kDa gelatinase/type IV collagenase) induced by tumour necrosis factor alpha correlates with metastatic ability in a human osteosarcoma cell line. 803 35

We have isolated a cDNA (NC28) transcribed from a mRNA which is transiently induced in U937 promonocytic cells by PMA and super-induced by cycloheximide. NC28 cDNA encodes a new member of the chemokine family, MCP-3, recently purified from MG-63 osteosarcoma cells by Van Damme et al. [1]. The MCP-3 protein sequence shows 74% identity with human monocyte chemoattractant protein 1 (MCP-1) and, like MCP-1, recombinant MCP-3 protein shows chemotactic activity for monocytes but not for neutrophils. However the secreted MCP-3 protein differs from MCP-1 in being N-glycosylated. The 3' noncoding regions of MCP-3 and MCP-1 mRNAs are more diverged (44%), allowing specific cDNA probes to be made, and indicating that the two genes are evolutionarily distant. Sequence comparisons of the 3' noncoding regions suggest that MCP-3 may be the human homologue of the mouse MARC gene [2], and that MCP-1 and MCP-3 genes arose by a gene duplication event before the mammalian radiation. Both MCP-1 and MCP-3 mRNAs are expressed by PBMC, principally by monocytes, with MCP-1 mRNA being expressed at levels 2-4 times that of MCP-3 mRNA. However, while MCP-1 mRNA is also expressed at high levels in fibroblast or astrocytoma cell lines after IL-1 and TNF stimulation, MCP-3 mRNA is expressed only at very low levels in these cells. The cellular origin of MCP-3 is thus more restricted than that of MCP-1. In our experiments on PBMC, LPS is not a consistent inducer of MCP-1 and MCP-3 mRNAs. In some experiments, it actually decreases levels of these two mRNAs, while concomitantly increasing IL-6 and TNF-alpha mRNA levels. Levels of MCP-1 and MCP-3 mRNAs in PBMC are both increased by IFN-gamma, although IL-6 mRNA is not induced. They are also increased by PHA-P and are decreased, in most cases, by IL-13 [3]. MCP-1 and MCP-3 mRNAs are thus co-ordinately regulated in monocytes in response to a number of inducing or inhibitory agents, in a manner differing in several respects from that of other monokines such as IL-6.
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PMID:Molecular cloning of the MCP-3 chemokine gene and regulation of its expression. 831 76

Isolated limb perfusion (ILP) with TNF alpha, IFN gamma and melphalan causes impressive tumour reduction in patients with irresectable soft tissue sarcomas with a high limb salvage rate. Since this therapy could be of value in patients with progressive osteosarcoma, we performed a study in an osteosarcoma tumour model in the rat. The ROS-1 osteosarcoma was implanted s.c. in the hind leg of WAG rats. Rats were divided in four groups: rats that underwent ILP with perfusate alone, TNF alpha alone, melphalan alone or their combination. Almost all rats, treated with a sham ILP or a perfusion with 40 micrograms melphalan, showed progressive disease (PD) (6/6 and 5/6). After perfusion with 50 micrograms TNF alpha alone a varied response was observed: 2/6 PD, 2/6 no change (NC) and 2/6 a complete remission (CR). After combined perfusion: 3/6 rats had a partial remission and 3/6 a CR. The best and most consistent responses are obtained by combining TNF alpha and melphalan. The discrepancy with the in vitro sensitivity of ROS-1 indicates that indirect effects are important in this tumour model.
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PMID:Isolated limb perfusion with TNF alpha and melphalan in a rat osteosarcoma model: a new anti-tumour approach. 860 32

The human osteosarcoma 143.98.2 cell line was found to express high levels of prostaglandin synthase-2 (PGHS-2) without detectable levels of prostaglandin synthase-1 (PGHS-1) as measured by reverse transcriptase-polymerase chain reaction (RT-PCR) and immunoblot analysis. Maximal levels of PGHS-2 induction were attained when the cells were grown beyond confluence. The osteosarcoma cells also secrete IL-1 alpha, IL-1 beta and TNF alpha in the culture medium. PGHS-2 expression was inducible by the exogenous addition of these cytokines as well as conditioned media from auto-induced cultures and inhibitable by treatment with dexamethasone. In contrast, undifferentiated U937 cells selectively express PGHS-1 as analyzed by RT-PCR and Western blotting. The effects of non-steroidal anti-inflammatory drugs (NSAIDs) on the cellular PGE2 production mediated by each isoform of human PGHS were determined using osteosarcoma and undifferentiated U937 cells. When cells were preincubated with inhibitors to allow time-dependent inhibition prior to arachidonic acid stimulation, NS-398, CGP 28238, L-745,337, SC-58125 all behaved as potent (IC50 = 1-30 nM) and selective inhibitors of PGHS-2, in contrast to indomethacin, flurbiprofen or diclofenac which are potent inhibitors of enzymes. DuP-697 and sulindac sulfide were also potent inhibitors of PGHS-2 but both compounds inhibited cellular PGHS-1 activity at higher doses (IC50 = 0.2-0.4 microM). Time-dependent inhibition of PGE2 production in osteosarcoma cells was observed for indomethacin, diclofenac and etodolac. The synthesis of PGE2 by U937 cells was strongly dependent on exogenous arachidonic acid (100-fold stimulation) whereas confluent osteosarcoma cells also produced PGE2 without exogenous stimulus (7-fold stimulation by arachidonic acid). Osteosarcoma cells grown beyond confluence released more PGE2 from endogenous substrate than arachidonic acid stimulated undifferentiated U937 cells. These results indicate that osteosarcoma cells selectively express PGHS-2 with an autocrine regulation and effective utilization of endogenous arachidonic acid for PGE2 synthesis.
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PMID:Characterization of autocrine inducible prostaglandin H synthase-2 (PGHS-2) in human osteosarcoma cells. 908 44

Osteosarcoma cell lines vary widely in their susceptibility to natural killer (NK) cell lysis in vitro although it is still unclear why this occurs. In this study we investigated the expression of some cell adhesion molecules on osteosarcomas to determine which of these can modify the susceptibility to NK lysis and we also attempted to modulate the cytolytic susceptibility of these targets with TNF alpha. We found that osteosarcoma lysis induced by NK cells correlates with different expression of the CD54 adhesion molecule on osteosarcomas and the increased susceptibility after TNF alpha treatment mostly depends on the expression of CD54 molecules on target cells.
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PMID:Human osteosarcoma cell susceptibility to natural killer cell lysis depends on CD54 and increases after TNF alpha incubation. 910 91

Oxidative stress has been frequently implicated in the initiation and promotion phases of carcinogenesis. Antioxidant enzymes, which can antagonize this process, are lowered in a number of malignancies even though different findings have been reported in the literature. It has been shown that tumors have less copper/zinc superoxide dismutase (Cu/Zn SOD) in comparison with the more metabolically active tissues, but there is a large overlap between normal and tumor tissue. In order to examine the relationship between osteosarcoma at different degrees of proliferation and differentiation and Cu/Zn SOD levels, four different human ostosarcoma cell lines: HOS, U-2 OS, MG63, Saos-2 were studied for their production and release of Cu/Zn SOD. A normal human stromal cell line was used as control. Osteosarcoma cells were stimulated with TNF alpha, a cytokine previously shown to have antiproliferative activity. The release of Cu/Zn SOD into the supernatant was higher for the HOS and U-2 OS lines when compared to the other cell lines evaluated both in basal condition and after incubation with TNF alpha. Elevated intracellular levels of Cu/Zn SOD were shown except for the HOS and U-2 OS which possess high concentrations of the enzyme at 24 hours declining during the other incubation periods. These concentrations were increased after TNF alpha treatment. The different behaviour of the four cell lines evaluated might be explained by their degree of differentiation.
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PMID:Copper/zinc superoxide dismutase expression by different human osteosarcoma cell lines. 961 84

A newly identified member of the tumor necrosis factor receptor (TNFR) superfamily shows activities associated with osteoclastogenesis inhibition and fibroblast proliferation. This new member, called TR1, was identified from a search of an expressed sequence tag database, and encodes 401 amino acids with a 21-residue signal sequence. Unlike other members of TNFR, TR1 does not contain a transmembrane domain and is secreted as a 62 kDa glycoprotein. TR1 gene maps to chromosome 8q23-24.1 and its mRNA is abundantly expressed on primary osteoblasts, osteogenic sarcoma cell lines, and primary fibroblasts. The receptors for TR1 were detected on a monocytic cell line (THP-1) and in human fibroblasts. Scatchard analyses indicated two classes of high and medium-high affinity receptors with a kD of approximately 45 and 320 pM, respectively. Recombinant TR1 induced proliferation of human foreskin fibroblasts and potentiated TNF-induced proliferation in these cells. In a coculture system of osteoblasts and bone marrow cells, recombinant TR1 completely inhibited the differentiation of osteoclast-like multinucleated cell formation in the presence of several bone-resorbing factors. TR1 also strongly inhibited bone-resorbing function on dentine slices by mature osteoclasts and decreased 45Ca release in fetal long-bone organ cultures. Anti-TR1 monoclonal antibody promoted the formation of osteoclasts in mouse marrow culture assays. These results indicate that TR1 has broad biological activities in fibroblast growth and in osteoclast differentiation and its functions.
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PMID:TR1, a new member of the tumor necrosis factor receptor superfamily, induces fibroblast proliferation and inhibits osteoclastogenesis and bone resorption. 965 24

The tumor necrosis factor receptor, p60 (TNF-R1), transduces death signals via the association of its cytoplasmic domain with several intracellular proteins. By screening a mammalian cDNA library using the yeast two-hybrid cloning technique, we isolated a ubiquitin-homology protein, DAP-1, which specifically interacts with the cytoplasmic death domain of TNF-R1. Sequence analysis reveals that DAP-1 shares striking sequence homology with the yeast SMT3 protein that is essential for the maintenance of chromosome integrity during mitosis (Meluh, P. B., and Koshland, D. (1995) Mol. Biol. Cell 6, 793-807). DAP-1 is nearly identical to PIC1, a protein that interacts with the PML tumor suppressor implicated in acute promyelocytic leukemia (Boddy, M. N., Howe, K., Etkin, L. D., Solomon, E., and Freemont, P. S. (1996) Oncogene 13, 971-982), and the sentrin protein, which associates with the Fas death receptor (Okura, T., Gong, L., Kamitani, T., Wada, T., Okura, I., Wei, C. F., Chang, H. M., and Yeh, E. T. (1996) J. Immunol. 157, 4277-4281). The in vivo interaction between DAP-1 and TNF-R1 was further confirmed in mammalian cells. In transient transfection assays, overexpression of DAP-1 suppresses NF-kappaB/Rel activity in 293T cells, a human kidney embryonic carcinoma cell line. Overexpression of either DAP-1 or sentrin causes apoptosis of TNF-sensitive L929 fibroblast cell line, as well as TNF-resistant osteosarcoma cell line, U2OS. Furthermore, the dominant negative Fas-associated death domain protein (FADD) protein blocks the cell death induced by either DAP-1 or FADD. Collectively, these observations highly suggest a role for DAP-1 in mediating TNF-induced cell death signaling pathways, presumably through the recruitment of FADD death effector.
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PMID:The ubiquitin-homology protein, DAP-1, associates with tumor necrosis factor receptor (p60) death domain and induces apoptosis. 1018 98

We investigated the expression of different chemokines in the surnatants and inside the cells of four human osteosarcoma cell lines. HOS, U-2 OS, MG63 and Saos-2 cells were cultured for 24, 48, 72 hours both in basal conditions and after stimulus with TNF alpha. Human stromal cells were used as control. IL-8 and MCP-1 are present in higher concentration in the surnatants in contrast to RANTES which is present primarily inside the cells. IL-8 and MCP-1 are not totally expressed by all the human osteosarcoma cell lines in unstimulated conditions, but became detectable after TNF alpha treatment. In general, this cytokine stimulated the production and release of the three chemokines.
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PMID:Expression of different chemokines by human osteosarcoma cells in response to tumor necrosis factor-alpha. 1065 98

The combination of chemotherapy with immunotherapy may offer an advantage over either therapy alone and provide a greater potential for total tumor eradication. Monocyte/macrophage-mediated tumor cell killing is a major mechanism of the host's defense against primary and/or metastatic neoplasia. We evaluated the tumoricidal activity against canine osteosarcoma cells of canine pulmonary alveolar macrophages (PAM) exposed in vitro to two recombinant canine (rc) cytokines (rcTNF alpha and rcIFN gamma). We also evaluated the in vivo tumoricidal activity of PAM from dogs treated with the macrophage activator, liposome-encapsulated muramyl tripeptide-phosphatidyl-ethanolamine (L-MTP-PE) alone or in combination with doxorubicin (DOX). This study demonstrated that rcTNF alpha and rcIFN gamma significantly enhance in vitro canine PAM cytotoxicity against canine osteosarcoma cells, and that PAM from dogs treated with DOX + L-MTP-PE have enhanced cytotoxic activity against osteosarcoma cells when compared to dogs treated with DOX or L-MTP-PE alone. These findings support the rationale for combining a chemotherapy agent with an immunotherapy agent for the treatment of metastatic disease, and suggest a role for TNF alpha and IFN gamma as agents for stimulating the antitumor activity of macrophages.
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PMID:In vitro and in vivo enhancement of canine pulmonary alveolar macrophage cytotoxic activity against canine osteosarcoma cells. 1085 Feb 95


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