Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Osteosarcomas and rhabdomyosarcomas are vigorously invading tumors. Before they can extravasate to the parenchymal organs and form metastases, they have to adhere to the endothelial cells lining the blood vessels and then penetrate through the endothelium. We show that several human sarcoma cell lines, osteosarcomas HOS, MG-63, U2-OS, and a rhabdomyosarcoma RD, express VLA-4 molecule on their surface and bind to the VCAM-I-expressing activated endothelial cell line Ea.hy 926. The increased sarcoma-cell adhesion could be abolished by treating the sarcoma cells with monoclonal antibodies (MAbs) VLA4 (both alpha- and beta-chain, HP2/1 and 4B4 respectively) or treating endothelial cells with VCAM-I antibody (4B9). Furthermore, we show that sarcoma cells adhere to recombinant soluble VCAM-I protein. On the other hand, these sarcoma cell lines do not express marked amounts of other ligands (such as CDII/18 or sialyl-Lex) for other endothelial adhesion molecules (ICAM-I, ICAM-2, E- and P-selectin) indicating that the VLA-4-VCAM-I dependent pathway might be of major importance in sarcoma extravasation. VLA-4 is not always in an avid form and therefore the expression of VLA-4 does not directly predict adherence to VCAM-I. The avidity of VLA-4 (measured by adherence to soluble VCAM-I) of MG-63 and U2-OS cells could be increased by a 30-min PMA treatment, whereas the avidity of VLA-4 on HOS cells increased only after 48 hr of PMA induction. Our results show that sarcoma cell lines (HOS, MG-63, U2-OS and RD) adhere to stimulated endothelium via VLA-4-VCAM-I adhesion molecules and that VLA-4 avidity on sarcoma cells can be differentially modulated by PMA.
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PMID:VLA-4 integrin on sarcoma cell lines recognizes endothelial VCAM-1. Differential regulation of the VLA-4 avidity on various sarcoma cell lines. 128 Nov 43

We investigated whether stromal cells obtained from human tonsils could interact and modulate the proliferation of the osteosarcoma cell in order to determine why lymph node metastases usually have a low incidence and remain occult using routine examinations. The effects of the supernatant of resting or activated stromal cells were analysed on osteoblastic cell proliferation of three different cell lines (HOS, U2, OS, MG-63). Only the proliferation of MG-63 was significantly inhibited. The direct adhesion of stromal cells to the osteosarcoma cell lines caused a greater inhibition of the proliferation of all three lines tested.
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PMID:Effect of stromal cells from human lymph nodes on the growth of osteosarcoma cell lines. 896 96

Metastatic osteosarcoma is a potential target for gene therapy, because conventional therapies are only palliative and metastatic disease is invariably fatal. Overexpression of the cyclin G1 (CYCG1) gene is frequently observed in human osteosarcoma cells, and its continued expression is found to be essential for their survival. Previously, we reported that down-regulation of cyclin G1 protein expression induced cytostatic and cytocidal effects in human MG-63 osteosarcoma cells (Skotzko et al., Cancer Research, 1995). Here, we extend these findings in a tumorigenic MNNG/HOS cell line and report on the effective inhibition of tumor growth in vivo by an antisense cyclin G1 retroviral vector when delivered as concentrated high titer vector supernatants directly into rapidly growing subcutaneous tumors in athymic nude mice. Histologic sections from the antisense cyclin G1 vector-treated tumors showed decreased mitotic indices and increased stroma formation within the residual tumors. Furthermore, in situ analysis of the cell-cycle kinetics of residual tumor cells revealed a decrease in the number of cells in S and G2/M phases of the cell cycle concomittant with an accumulation of cells in the G1 phase. Taken together, these studies demonstrate in vivo efficacy of a high-titer antisense cyclin G1 retroviral vector in an animal model of osteosarcoma.
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PMID:Retroviral vector-mediated transfer of an antisense cyclin G1 construct inhibits osteosarcoma tumor growth in nude mice. 932 69

This study aimed at clarifying the role of Aminopeptidase N (APN), a Zn2+-dependent ectopeptidase localized on the cell surface of human osteosarcoma cell lines treated with proinflammatory cytokines. We investigated the proinflammatory cytokines interleukin-1 beta (IL-1beta), IL-6 and tumor necrosis factor alpha (TNF-alpha) as well as the anti-inflammatory cytokine transforming growth factor beta (TGF-beta) for their influence on APN regulation. Soluble IL-6 receptor (sIL-6R) was always used together with IL-6 to achieve a stable effect. In addition, the invasive potential of the osteosarcoma cell lines MG63 and HOS was examined. Competitive RT-PCR and Ala-pNA activity assays revealed that IL-6 and sIL-6R significantly increased the mRNA expression and activity of APN in both osteosarcoma cell lines. Although IL-1beta significantly stimulated APN mRNA expression in both cell lines, it influenced the enzyme activity only in MG63. TNF-alpha and TGF-beta, however, had an effect neither on mRNA expression nor on the enzyme activity of APN in both cell lines. In the Matrigel invasion assay, IL-6 and sIL-6R significantly up-regulated the transmigration of these cell lines, whereas other cytokines did not. The up-regulated invasion was inhibited by bestatin, a specific inhibitor of APN. Cellular migration correlated highly with APN activity (r = 0.79, P < 0.002). These findings suggest that APN contributes to the invasive potential of human osteosarcomas enhanced by IL-6 and SIL-6R.
Clin Exp Metastasis 1999
PMID:Possible contribution of aminopeptidase N (APN/CD13) to invasive potential enhanced by interleukin-6 and soluble interleukin-6 receptor in human osteosarcoma cell lines. 1108 84

Matrix degrading enzymes released upon autocrine and/or paracrine induction exert a key role in modulating tumor cell behavior. Osteosarcoma is a highly metastatic cancer, with a redundancy of autocrine loops. Here we report that human osteosarcoma cells express a wide array of chemokine receptors and respond to chemokine activation with the release of N-acetyl-beta-D-glucosaminidase and gelatinase/collagenase activity. Of the two cell lines studied, the osteoblast-like MG-63 showed a higher responsivity compared to the less differentiated HOS. This suggests that chemokine modulation of matrix degrading enzymes requires the maintaining of the osteoblastic phenotype and of signaling pathways which occur in normal tissue.
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PMID:Human osteosarcoma cells release matrix degrading enzymes in response to chemokine activation. 1111 33

Although the mechanism is unknown, infiltration anesthetics are believed to have membrane-stabilizing action. We report here that such a most commonly used anesthetic, lidocaine, effectively inhibited the invasive ability of human cancer (HT1080, HOS, and RPMI-7951) cells at concentrations used in surgical operations (5-20 mM). Ectodomain shedding of heparin-binding epidermal growth factor-like growth factor (HB-EGF) from the cell surface plays an important role in invasion by HT1080 cells. Lidocaine reduced the invasion ability of these cells by partly inhibiting the shedding of HB-EGF from the cell surface and modulation of intracellular Ca2+ concentration contributed to this action. The anesthetic action of lidocaine (sodium channel blocking ability) did not contribute to this anti-invasive action. In addition, lidocaine (5-30 mM), infiltrated around the inoculation site, inhibited pulmonary metastases of murine osteosarcoma (LM 8) cells in vivo. These data point to previously unrecognized beneficial actions of lidocaine and suggest that lidocaine might be an ideal infiltration anesthetic for surgical cancer operations.
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PMID:Infiltration anesthetic lidocaine inhibits cancer cell invasion by modulating ectodomain shedding of heparin-binding epidermal growth factor-like growth factor (HB-EGF). 1212 80

Aminopeptidase N (APN/CD13), a Zn2+-dependent ectopeptidase, is localized on the cell surface and functions as a transmembrane protein. Increased expression and activity of APN have been postulated to correlate with the aggressive behavior of several tumor types. In this study, the osteosarcoma cell line MNNG/HOS was stably transfected with an expression vector capable of expressing the antisense transcript of APN. Four stably transfected clones, the control clones and parental cells were characterized. Stable integration of the antisense vector was confirmed by PCR analysis of genomic DNA. Competitive RT-PCR revealed that mRNA expression of antisense-transfectants was decreased to approximately 37% of the control cell line. The activity assay showed that the enzymatic activity of APN was inhibited to approximately 51% of the control cell line. Antisense-transfection had no influence on the cellular proliferation measured by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, on the motility in Transwell chambers, and on the adhesive potential to collagen I. However, an in vitro invasion assay revealed a significant decrease in the number of cells that migrated through a reconstituted membrane (51% of the control cell line). The adhesive potential to Matrigel was also affected (73% of the control cell line). Furthermore, under in vivo conditions, a reduced potency to metastasize to the lung was shown in an experimental metastasis assay in nude mice. These findings demonstrate that APN plays an active role in the cellular attachment and proteolytic degradation of the extracellular matrix in the metastatic process of osteosarcomas.
Clin Exp Metastasis 2003
PMID:Inhibitory effect of antisense aminopeptidase N (APN/CD13) cDNA transfection on the invasive potential of osteosarcoma cells. 1466 89

Osteosarcoma is the most common primary malignancy of bone and patients often develop pulmonary metastases. In order to investigate the pathogenesis of human osteosarcoma, there is a great need to develop a clinically relevant animal model. Here we report the development of an osteosarcoma animal model using three related human osteosarcoma lines, the parental TE-85 and two derivative lines MNNG/HOS and 143B. In vitro characterization demonstrated that the 143B line had the greatest cell migration and the least cell adhesion activities among the three lines. The 143B line also exhibited the greatest ability for anchorage independent growth. When GFP-tagged osteosarcoma cells were injected into the proximal tibia of athymic mice, we found that 143B cells were highly tumorigenic and metastatic, and MNNG/HOS cells were tumorigenic but significantly less metastatic. TE85 cells were neither tumorigenic nor metastatic. The number of pulmonary metastases was found 50-fold higher in 143B injected animals than that in MNNG/HOS injected mice. No pulmonary metastases were detected in TE85 injected animals for up to 8 weeks. Primary tumors formed by MNNG/HOS and 143B cells could be visualized by whole body fluorescence imaging, while the pulmonary metastases were visualized on the necropsied samples. The GFP tagged 143B cells (and to a lesser extent, MNNG/HOS cells) were readily recovered from lung metastases. This clinically relevant model of human osteosarcoma provides varying degrees of tumor growth at the primary site and metastatic potential. Thus, this orthotopic model should be a valuable tool to investigate factors that promote or inhibit osteosarcoma growth and/or metastasis.
Clin Exp Metastasis 2005
PMID:An orthotopic model of human osteosarcoma growth and spontaneous pulmonary metastasis. 1617 Jun 68

Osteosarcoma is one of the most common primary malignant tumors of the bone in children and adolescents. Some patients continue to have a poor prognosis, as they have metastatic disease and frequent occurrence of drug resistance. Zoledronate is a nitrogen-containing bisphosphonate that has been used for the treatment of hypercalcemia and bone metastasis, because it induces apoptosis in osteoclasts and tumor cells by inhibiting the isoprenylation of intracellular small G proteins. Besides inhibiting isoprenylation, little is known about the manner by which bisphosphonates inhibit cellular proliferation and induce apoptosis. This prompted us to investigate the inhibitory effects of zoledronate in human osteosarcoma cell lines, HOS and MG63. HOS cells accumulated in S phase around 6 h after treatment with 10 microM zoledronate, followed by apoptosis. When HOS cells were treated with zoledronate, ATM kinase and its substrate, check-point kinase (Chk)1, were phosphorylated. Zoledronate also induced phosphorylation of cdc25a (Thr506) in HOS cells, which is a substrate of Chk1, and its phosphorylation is known to be critical for S phase arrest. Following treatment with zoledronate, phosphorylated histone H2AX (gamma-H2AX) displayed patterns of nuclear foci in HOS cells. As gamma-H2AX accumulates at dsDNA breaks, these results demonstrate that zoledronate induced DNA damage and S phase arrest, accompanied by activation of the ATM/Chk1/cdc25 pathway in a human osteosarcoma cell line.
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PMID:Zoledronate-induced S phase arrest and apoptosis accompanied by DNA damage and activation of the ATM/Chk1/cdc25 pathway in human osteosarcoma cells. 1761 84

The development of pulmonary metastasis is the major cause of death in osteosarcoma, and its molecular basis is poorly understood. In this study, we show that beta4 integrin is highly expressed in human osteosarcoma cell lines and tumor samples. Furthermore, highly metastatic MNNG-HOS cells have increased levels of beta4 integrin. Suppression of beta4 integrin expression by shRNA and disruption of beta4 integrin function by transfection of dominant-negative beta4 integrin was sufficient to revert this highly metastatic phenotype in the MNNG-HOS model without significantly affecting primary tumor growth. These findings suggest a role for beta4 integrin expression in the metastatic phenotype in human osteosarcoma cells. In addition, we identified a previously uncharacterized interaction between beta4 integrin and ezrin, a membrane-cytoskeletal linker protein that is implicated in the metastatic behavior of osteosarcoma. The beta4 integrin-ezrin interaction appears to be critical for maintenance of beta4 integrin expression. These data begin to integrate ezrin and beta4 integrin expression into a model of action for the mechanism of osteosarcoma metastases.
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PMID:Beta4 integrin promotes osteosarcoma metastasis and interacts with ezrin. 1959 68


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