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 investigated both constitutive- and cytokine-induced secretion of interleukin-8 (IL-8) and its regulation by dexamethasone and 17 beta-estradiol in normal human bone marrow stromal (HBMS), osteoblast-like cells (hOB), and osteosarcoma MG-63 cells. Although HBMS cells secrete low levels of IL-8 constitutively, treatment with IL-1 beta and tumor necrosis factor-alpha (TNF-alpha) induced IL-8 secretion. Their effects were synergistic but IL-8 production was not affected by 17 beta-estradiol. Human osteosarcoma MG-63 cells also secreted low levels of IL-8 constitutively; the production was induced by IL-1 beta and TNF-alpha and was also not affected by 17 beta-estradiol. The magnitude of the response to cytokine stimulation of IL-8 in MG-63 cells was much lower than that of HBMS and hOB cells, indicating differences in response in normal and osteoblastic osteosarcoma cells. Dexamethasone (10(-7) M) significantly inhibited IL-1 beta plus TNF-alpha stimulated IL-8 production in HBMS, MG-63, and hOB cells. The accumulated results demonstrate that IL-8 is secreted by HBMS, MG-63, and hOB cells, suggesting that IL-8 may play a role in the regulation of bone cell function. These data also emphasize the importance of glucocorticoids in controlling cytokine secretion in HBMS, hOB, and MG-63 cells.
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PMID:Dexamethasone regulates IL-1 beta and TNF-alpha-induced interleukin-8 production in human bone marrow stromal and osteoblast-like cells. 792 84

Monocyte chemotactic proteins (MCP) belong to a group of structurally and functionally related factors, called chemokines. To facilitate additional characterization of the recently identified MCP-2, the 76-residue protein was chemically synthesized. The synthetic 7-kDa monomeric protein was chemotactic for monocytes at 1 nM and was biochemically similar to natural MCP-2. Sensitive radioimmunoassays for both MCP-1 and MCP-2 were developed. These RIAs were specific in that no cross-reactivity could be observed, and other chemokines or cytokines were not detected. Induction of MCP-1 and MCP-2 in human diploid fibroblasts and peripheral blood leukocytes as well as osteosarcoma, epidermal carcinoma, and melanoma cells by the cytokines IL-1 beta, IFN-beta, and IFN-gamma and cytokine inducers such as dsRNA, virus, endotoxin, mitogen, and phorbol ester was studied. In connective tissue cells, IL-1 beta was the best inducer of MCP-1, but IFN-gamma was a superior inducer of MCP-2. Mononuclear cells also proved to be a source of MCP-1 and MCP-2 when stimulated by most of the inducers tested. Granulocytes, however, were inefficient producers. Measles virus induced MCP-1 and MCP-2 in most cell types. In general, the yields of MCP-2 were at least 10-fold lower than those of MCP-1. It is concluded that, although MCP-2 is often coproduced with MCP-1, regulation of expression of the two chemokines is not identical. It remains to be studied under which pathological conditions MCP-2 is released in vivo and whether MCP-1 and MCP-2 can activate different target cells.
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PMID:Induction of monocyte chemotactic proteins MCP-1 and MCP-2 in human fibroblasts and leukocytes by cytokines and cytokine inducers. Chemical synthesis of MCP-2 and development of a specific RIA. 818 67

Upon entering a cell the natural product rapamycin, like the structurally related immunosuppressant FK506, associates with members of the FKBP family of proteins. One or more of the resulting FKBP-rapamycin complexes blocks signaling pathways emanating from some growth factor receptors. Recently, the addition of rapamycin was shown to inhibit the phosphorylation and activation of a 70-kDa ribosomal S6 protein kinase, which normally occurs minutes after the activation of certain cytokine and growth factor receptors. We now report that rapamycin can be added 4 to 6 h after the addition of serum growth factors to quiescent human osteosarcoma cells and still arrest these cells in G1. This window of action correlates with the inducible appearance of a cyclin-dependent kinase (cdk) activity, and the induction of this activity is inhibited by the addition of rapamycin. Furthermore, p36cyclin D1 associates with this cdk protein complex in lysates of untreated cells, but does not associate with this cdk protein complex in lysates of rapamycin-treated cells. Together, these studies demonstrate that FKBP-rapamycin can modulate a cyclin-dependent kinase activity and a cyclin D1-cdk association during early G1 in MG-63 human osteosarcoma cells.
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PMID:FKBP-rapamycin inhibits a cyclin-dependent kinase activity and a cyclin D1-Cdk association in early G1 of an osteosarcoma cell line. 822 93

Liposomal muramyl tripeptide phosphatidylethanolamine (L-MTP-PE) is a biological agent in phase I and II trials for osteosarcoma and melanoma. Its mechanism of action has been linked to its ability to activate monocyte tumoricidal function and to stimulate monocyte production of tumor necrosis factor (TNF) and interleukins(IL)-1, -6, and -8. Our ultimate goal is to combine L-MTP-PE with chemotherapy. The purpose of this study was to determine whether doxorubicin (Adriamycin) interfered with the ability of L-MTP-PE to activate monocyte cytokine production. Human monocytes were cultured with or without 5-500 ng/ml of Adriamycin for 3 h and washed before being exposed to 2 micrograms/ml L-MTP-PE for 16 h. Cultured supernatants were collected and assayed for TNF, IL-1, IL-6, and IL-8. The messenger RNA expression of IL-1 alpha, IL-1 beta, TNF alpha, IL-6, and IL-8 was quantified with northern blot analysis. Adriamycin did not suppress the up-regulation of any of these cytokines. We concluded that combination therapy with L-MTP-PE and Adriamycin is feasible and that this combination warrants further investigation in a clinical setting.
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PMID:Effect of Adriamycin on liposomal muramyl tripeptide's ability to up-regulate monocyte cytokine expression. 824 65

We investigated the expression of cytokine transcripts in osteoblast-like cells derived from explants of pagetic and normal bone. A reverse transcription-linked PCR was used that allowed the simultaneous analysis of a range of cytokines. Normal osteoblast-like cells were found to contain the transcripts for IL-1 beta, IL-6, and TGF-beta 1. For the first time we detected in bone cells the two other mammalian isoforms of TGF-beta, beta 2, and beta 3. Furthermore, we have also identified mRNA for IL-3 and the novel chemotactic factor, IL-8. Using this sensitive technique it was not possible to detect mRNA for IL-1 alpha, IL-2, IL-4, IL-5, IL-7, TNF-alpha, or interferon-gamma. The human osteosarcoma cell line Saos-2 also showed a similar pattern of expression of these cytokines to primary osteoblast-like cells, with the exception that TNF-alpha was also identified. Cells isolated from pagetic bone showed essentially the same profile of cytokine expression as normal bone except that TNF-alpha was also detected in two of four samples. The cytokine profile of successive populations of cells harvested from one explant culture at 9, 22, and 57 days showed a consistent pattern of cytokine expression, demonstrating the phenotypic stability of the osteoblast-like cells in long-term cultures.
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PMID:PCR detection of cytokines in normal human and pagetic osteoblast-like cells. 825 52

When human MG-63 osteosarcoma cells are triggered with IL-1 beta, they produce, among various other cytokines, also monocyte chemotactic proteins (MCPs). Homogeneous MCP-1, MCP-2 and MCP-3 were found to induce production of gelatinase B and chemotaxis of monocytes. Based on the almost complete amino acid sequence of natural MCP-3, two sets of degenerated oligonucleotides were used for the amplification of MCP-3 cDNA. Total RNA from stimulated MG-63 cells was reverse transcribed and PCRs done on the mRNA:cDNA duplex. Using the PCR-product, several cDNAs were isolated from a cDNA library of IL-1-stimulated MG-63 cells. From the cDNA sequence the complete primary structure of the protein was deduced: MCP-3 shows 71% and 58% amino acid homology with MCP-1 and MCP-2, respectively. Our study establishes MCP-3 as an inflammatory cytokine that regulates macrophage functions. Because MCP-3 is often produced by tumor cell lines and regulates protease secretion by macrophages, its production might also contribute to invasion and metastasis of cancer cells.
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PMID:Human monocyte chemotactic protein-3 (MCP-3): molecular cloning of the cDNA and comparison with other chemokines. 846 Oct 11

Prostate tumor cells preferentially metastasize to bony sites and lymph nodes at a frequency in excess of that which would be predicted by random tumor cell dissemination. In order to determine whether chemoattractants in these organs promote organ-specific metastasis, we utilized human cell lines derived from and/or related to these organs as sources of potential chemoattractants. Secretory proteins derived from the cell lines MG-63 (osteosarcoma), SK-ES-1 (Ewing's sarcoma), and KG-1 (leukemia) stimulated chemomigration of the TSU-pr1 prostate tumor cells in a dose-dependent manner in Boyden chambers. In addition, secretory proteins from a human prostatic stromal cell line (hPS) and from the TSU-Pr1 prostate tumor cell line were also able to stimulate chemomigration of the TSU-pr1 cells through Boyden chambers. Since lymph nodes and bony sites represent organs of hematopoietic/lymphoid proliferation and activation, we undertook identification of specific cytokines present at these sites which may promote the chemomigration of prostate tumor cells. In this context, the cytokines interleukin-1 alpha, interleukin-2, interleukin-6, tumor necrosis factor-beta, transforming growth factor-beta, interferon alpha 2-a, and granulocyte-macrophage colony-stimulating factor did not stimulate chemomigration of the TSU-pr1 prostate tumor cell line. In contrast, the cytokine epidermal growth factor (EGF) stimulated chemomigration of the TSU-pr1 prostate tumor cells through the Boyden chambers in a dose-dependent manner. Western blot analysis of secretory proteins from the cell lines KG-1, SK-ES-1, MG-63, hPS, and TSU-pr1 identified EGF-immunoreactive proteins in all cases. In addition, EGF immunoreactivity was localized to the stroma of the human prostate, the osteogenic stroma of pelvic medullary bone, and the stroma within the capsule and trabeculae of pelvic lymph nodes. Hence, these results demonstrate that the cytokine EGF promotes the chemomigration of the TSU-pr1 prostate tumor cell line, and that EGF within the stroma of pelvic lymph nodes and medullary bone may act as a chemoattractant for prostate tumor cells, thereby facilitating the preferential formation of metastatic foci within these organs.
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PMID:Epidermal growth factor (EGF) promotes chemomigration of a human prostate tumor cell line, and EGF immunoreactive proteins are present at sites of metastasis in the stroma of lymph nodes and medullary bone. 854 75

This paper demonstrates that epidermal cells in culture produce an activity which can increase the frequency of Ia+ epidermal Langerhans cells (LC). This was achieved by treating mice topically with a mixture containing supernatant derived from primary culture of murine epidermis (ES) and a synthetic corticosteroid, triamcinolone acetonide (TAC). The presence of the supernatant in the mixture partially protected the Ia+ LC from depletion by the steroid. The Ia+ LC frequency increasing activity was measured as the difference between the Ia+ LC frequency due to treatment with steroid mixed with supernatant and the Ia+ LC frequency due to treatment with steroid mixed with negative control medium. The mean frequency of Ia+ LC in epidermis treated with TAC mixed with ES was 606(SD 43) cells/mm2, as compared with 486 (SD 68) cells/mm2 in the epidermis treated with TAC mixed with control medium. The activity appeared to be caused by (a) proteinaceous factor(s). A fraction of ES which was retained above a > or = 10 KDa molecular weight cut-off membrane was capable of partially protecting Ia+ LC frequency from TAC depletion. Supernatants from cultured lymph nodes, dermis as well as the squamous cell carcinoma lines T7 and T79, but not the human osteosarcoma cell-line 143B, also contained similar activities. We demonstrate that GM-CSF also increased the number of Ia+ epidermal LC when applied topically to mouse skin in this system. Therefore, using this Ia+ LC frequency modulation system, we propose that GM-CSF is one example of a cytokine which may be involved in the regulation of Ia+ LC numbers in epidermis and that epidermal cells produce factors which can increase the number of Ia+ LC.
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PMID:Modulation of Ia+ Langerhans cell numbers in vivo by cultured epidermis derived supernatants and by GM-CSF. 862 9

Following exogenous administration of transforming growth factor-beta 1 (TGF-beta 1) polypeptide to the human osteosarcoma cell line TE-85, we observed a 2- to 6-fold stimulation of steady-state TGF-beta 1 mRNA. The stimulation was dose- and time-dependent, as judged from Northern blot hybridization analyses. A 2- to 6-fold increase of the TGF-beta 1 polypeptide was also found in the media of these cells after TGF-beta 1 treatments. The autostimulation of TGF-beta 1 mRNA was nullified by cycloheximide treatment of the cells. The in vitro transcription rates of the TGF-beta 1 gene by isolated nuclei were not altered by TGF-beta 1 treatment. Under conditions of transcriptional inhibition, the stability of TGF-beta 1 mRNA was enhanced nearly two-fold by TGF-beta 1 treatment. Our findings indicate that TGF-beta 1 can stimulate autologous gene expression and subsequent polypeptide translation by a post-transcriptional mechanism requiring protein synthesis in human osteoblast-like cells. The recognized versatility of TGF-beta 1 autostimulation mechanisms (transcriptional and post-transcriptional) in other mesenchymal cells may apply also to skeletal cells, further underscoring the broad and potent activities of this cytokine.
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PMID:Post-transcriptional stimulation of transforming growth factor beta 1 mRNA by TGF-beta 1 treatment of transformed human osteoblasts. 882 45

Steady progress in the delineation of prognostic factors and the identification of genetic alterations and of potential mechanisms of oncogenesis mark the contributions to the literature on osteosarcoma for the past year. A new cytokine and chemotherapy combination has shown promise, and additional work on chemotherapy regimens containing ifosfamide will undoubtedly stimulate interest in a new generation of randomized clinical trials that will be essential for further refinement of therapy for osteosarcoma.
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PMID:Osteosarcoma and other tumors of bone. 886 4


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