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Query: UMLS:C0029463 (osteosarcoma)
 16,637 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Clinical observations have demonstrated a positive effect of estrogens and androgens on the maintenance of structural bone integrity. This study examines the direct effects of androgenic hormones on the osteoblast-like human osteosarcoma cell line, HOS TE85. Employing radiolabeled dihydrotestosterone (DHT), 2800 saturable, high-affinity (dissociation constant = 0.66 nM) androgen binding sites were detected per HOS TE85 cell. Androgen binding was specific in that DHT and testosterone (T) displayed significantly greater competition than the progestins, progesterone and medroxyprogesterone. The expression of androgen receptors in HOS TE85 cells was further substantiated by Northern analysis. A human androgen receptor complementary DNA probe revealed a 9.5 kilobase transcript which corresponds to the predominant human androgen receptor transcript detected in human male reproductive tissues. Androgens were also found to elicit biological responses in HOS TE85 cells. Physiological concentrations of DHT and T decreased HOS TE85 cell proliferation as assessed by cell count. This finding suggests that DHT may also play a role in osteoblast differentiation. In support of this hypothesis, treatment with T (24 h, 10 nM) enhanced the abundance of both alpha 1(I)-procollagen messenger RNA (mRNA) (5-fold) and transforming growth factor-beta mRNA (2.2 fold). The nonaromatizable androgen DHT (24 h, 10 nM) elicited an increase in the steady state concentration of alpha 1(I)-procollagen mRNA similar to the increase observed with T treatment. Thus, in addition to the recent discovery of estradiol receptors and estrogenic regulation of HOS TE85 cells, it is now evident that these osteoblast-like osteosarcoma cells also express high affinity androgen binding sites and can respond biologically to androgens.
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PMID:High-affinity androgen binding and androgenic regulation of alpha 1(I)-procollagen and transforming growth factor-beta steady state messenger ribonucleic acid levels in human osteoblast-like osteosarcoma cells. 203 57

Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) promotes the growth of a variety of hematopoietic and nonhematopoietic cells, both benign and malignant. There is now evidence that osteoblast-like cells produce GM-CSF and their growth is stimulated by this cytokine in vitro. We have studied the effect of rhGM-CSF on DNA synthesis and cell proliferation in the human osteogenic sarcoma cell lines U-20S, G-292, MG-63, and HOS. RhGM-CSF stimulated a dose-dependent increase in radioactive thymidine incorporation in each of the four cell lines in the presence of serum-free media, and in two cell lines (HOS and U-20S) in the presence of fetal bovine serum (FBS). In addition, rhGM-CSF produced significant increases in cell proliferation in two cell lines (MG-63 and U-20S) in the presence of 2% FBS. These results suggest that GM-CSF may have an important role in the biology of human osteogenic sarcoma cells. The clinical implications of these findings merit further investigation.
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PMID:The effect of rhGM-CSF on the proliferation of osteogenic sarcoma cells. 206 68

The presence and functions of steroid receptors were evaluated in three human osteosarcoma cell lines (OS1 = SA OS; OS2 = HOS TE 85, and OS3 = MNNG HOS TE 85). The human breast cancer cell line MCF-7 was used as internal control for oestrogen receptors (E2R). High and low affinity sites were characterised. The high affinity sites had a similar dissociation constant in all four cell lines. In contrast, the number of sites per cell was higher in MCF-7 cells. E2 did not significantly modify the number of progesterone receptors (PgR) per cell in any of the osteosarcoma lines. As expected, E2 increased the number of PgR sites per MCF-7 cell. 4-hydroxytamoxifen decreased the growth of MCF-7 cells only. OS1 and OS2 were sensitive only to the highest concentration tested, which produces only non-specific cytotoxic effects. Thus E2R and PgR were found in osteoblast-like cells, but the function of E2R in such cells remains unknown.
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PMID:Steroid receptors in human osteoblast-like cells. 214 99

Stable SV40 transformation of the human osteosarcoma cell line HOS yielded SV-HOS cells with high levels of large-T and quasi-original levels of p53. The latter kept its former intermediate metabolic stability, was found to be uncomplexed with SV40 large-T, however coimmunopurified with a 70 kDa protein. Upon comparison with HOS, SV40-HOS cells showed decreased serum-dependence and increased colony-forming efficiency in soft agar. SV-HOS cells were non-invasive in an in vitro assay in contrast with SV40-transformed human cells exhibiting a classical large-T-p53 complex. Both SV40-transformed human cell types were poorly tumorigenic in athymic mice in contrast with transformed HOS cells, expressing activated v-ras or met oncogenes. The p53 molecules from HOS cells and any of the HOS derivatives were underphosphorylated and showed unusual methionine- and phosphate-containing peptide fingerprints when compared with 'normal' human p53, which can associate with SV40 large-T. The structural and biological features of the HOS p53 molecules are discussed in relationship to analogous human and murine molecules in experimental and natural systems.
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PMID:Partial transformation of human tumor cell lines showing defective interaction between unusual p53 gene product and SV40 large-T antigen. 215 84

Three murine hybridomas (TMMR-1-3) were developed by repeated immunizations of mice with four different human osteosarcoma cell lines in an alternating sequence of inoculations. The monoclonal antibodies were screened for reactivities to cultured cell lines and tissue sections of osteosarcomas using flow cytometry and immunohistochemical techniques. TMMR-2 is a highly specific antibody (IgG1) that reacted with all 14 osteosarcoma tumors and eight human osteosarcoma cell lines tested, including the established human osteosarcoma cell lines HOS and Saos-2. Benign neoplastic cells from two osteoblastomas, osteoblasts from regions of reparative osteoid formation and neonatal new bone, are also reactive with TMMR-2. TMMR-1 has mesenchymal specificity while TMMR-3, although reactive with osseous differentiated cells, also reacted with mitotic cells of all cell types. Characterization of antigen structure by Western immunoblotting revealed that TMMR-2 reacted with a 100 degrees C heat labile mercaptoethanol-sensitive Mr 26,000 protein, and TMMR-3 recognized a mercaptoethanol-resistant Mr 97,000 protein whereas TMMR-1 reacted with a series of bands from 65,000 to 85,000 molecular weight, all of which were mercaptoethanol sensitive. TMMR-1 and TMMR-2 monoclonal antibodies showed complement-independent inhibition of [3H]thymidine incorporation into DNA, but did not exhibit cytotoxic activity. The results suggest that TMMR-2 is a specific antibody that recognizes an osteoblast/osteocyte surface antigen present in normal, reactive, and neoplastic disorders of bone. The inhibitory effects on DNA synthesis in cultured osteosarcoma cells by TMMR-2 indicate an important cell growth/proliferation role of this surface antigen. These monoclonal antibodies, in combination with other known antibodies, can be used to characterize mesenchymal cell surface antigenic structure and differentiation.
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PMID:Monoclonal antibody to human osteosarcoma: a novel Mr 26,000 protein recognized by murine hybridoma TMMR-2. 229 50

CCC/2M, CCC/10Y and CCC/MT-2 cat kidney cells producing Japanese isolates of human T-cell leukemia virus type I (HTLVs) and HOS/PL human osteosarcoma cells producing an American isolate of HTLV were infected with vesicular stomatitis virus (VSV) to prepare VSV pseudotypes bearing envelope antigens of HTLVs. VSV propagated in CCC/2M cells contained plaque-forming fractions that were not neutralized by treatment with anti-VSV serum alone: VSV pseudotypes bearing envelope antigens of HTLV2M and CCC cat endogenous virus were formed by infection of CCC/2M cells with VSV. Japanese HTLV2M, HTLV10Y and HTLVMT-2 and American HTLVPL pseudotypes were neutralized by sera of Japanese, American and British patients with ATL. Each serum, including the serum of the patient from whom HTLV2M or HTLV10Y had been derived, gave similar antibody titers against Japanese and American HTLV pseudotypes. The HTLV pseudotypes were also neutralized by rabbit serum raised against HTLVMT-2. A rabbit antiserum against the C-terminal half of the HTLV env protein produced in E. coli also neutralized Japanese and American HTLV pseudotypes. Thus, VSV pseudotype analyses indicated that envelope antigens of HTLVs represent a single serotype worldwide. The env protein produced in E. coli may be used to raise neutralizing antibody against HTLVs.
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PMID:Human T-cell leukemia virus type I: pseudotype neutralization of Japanese and American isolates with human and rabbit sera. 241 68

Highly purified interleukin 1 (IL 1) obtained from stimulated human monocytes appeared to be growth inhibitory and cytocidal for a human melanoma cell line, A375. Although IL 1 did not have an immediate cytolytic effect, with time in culture the growth of the target cells was irreversibly inhibited. The cells eventually lysed and decreased markedly in number; the IL 1 effect can therefore be said to be cytocidal. IL 1 activity could not be separated from the cytocidal activity by a variety of chromatography procedures by using conventional and high-performance liquid chromatography (HPLC). The A375 melanoma cell line was also sensitive to another human cytokine alpha-lymphotoxin (alpha-LT) derived from a human B cell line. IL 1 also appeared to be partially growth inhibitory and cytocidal for a LT-sensitive mouse fibroblast cell line, L929; but not for LT-resistant cells, including a subline of L929; a human epithelial carcinoma cell line, HeLa; a human osteosarcoma cell line, HOS; and a mouse SV40-transformed kidney cell line, TU5. However, the LT-sensitive mouse fibroblast cell line, L-M, was resistant to IL 1. Therefore, the cytocidal activity of IL 1 only partially overlapped the target cell selectivity of alpha-LT. Although natural IFN-alpha and recombinant IFN-beta were appreciably growth inhibitory for the A375 cell line, natural and recombinant IFN-alpha and recombinant IFN-beta and IFN-gamma exhibited little cytocidal activity. Purified IL 1 did not have any antiviral activity, and conversely, IFN and alpha-LT were not co-mitogenic for thymocytes. Furthermore, by ELISA and radioimmunoassays, antibodies against human alpha-LT, tumor necrosis factor, and IFN-gamma did not react with IL 1, indicating that IL 1 is antigenically distinct from these other cytokines. These in vitro results suggest that IL 1 may play a role in host defense against some tumors as a cytocidal factor.
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PMID:Human interleukin 1 is a cytocidal factor for several tumor cell lines. 241 93

The objective of this study was to establish whether human recombinant tumor necrosis factor (TNF) can significantly stimulate the proliferation of some tumor cells. Treatment with TNF had little or no effect on the growth of human tumor cells and murine NIH/3T3 cells cultured in medium with high serum concentration. Two tumor lines, SK-MEL-109 melanoma and HOS osteosarcoma cells, were adapted to grow in medium supplemented with 0.5% serum. The growth of these SK-MEL-109 cells was inhibited by TNF, but that of the HOS cells was greatly stimulated by TNF in a dose-dependent way. Treatment with 10 ng/ml of TNF resulted in a two-fold increase in the rate of cell division. This effect of TNF was also shown by measuring DNA and protein synthesis. The continuous presence of TNF was not required for its mitogenic activity on HOS cells cultured with 0.5% serum, since treatment for only one day with TNF resulted in prolonged growth stimulation. The failure of TNF to promote division of cells cultured in medium with 10% serum may possibly be explained by the presence of saturating amounts of growth factors in serum. Interferons abolished the mitogenic activity of TNF on HOS cells. Furthermore, TNF did not show synergism with insulin or epidermal growth factor in stimulating growth of these cells. The level of c-myc mRNA was increased five-fold after 30 minutes of treatment with TNF. This shows that TNF is a growth factor for HOS cells and that it induces accumulation of c-myc mRNA.
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PMID:Tumor necrosis factor stimulates proliferation of human osteosarcoma cells and accumulation of c-myc messenger RNA. 245 Aug 80

The human osteosarcoma cell line Te85 clone F-5 is not tumorigenic in vivo. Its transformation with Kirsten murine sarcoma virus (KiMSV) (KHOS) confers full malignant properties and stable non-tumorigenic revertants of this KHOS cell line have been obtained. Here we show that integration and expression of a single copy of the KiMSV proviral DNA, which is totally lost in the HOS 240S revertant, is responsible for the acquisition of tumorigenicity. Cytogenetic analysis and the absence of a residual LTR copy in the revertant cellular genome suggest that the loss of KiMSV provirus is caused either by chromosomal segregation or by recombination not involving the LTR. In addition analysis of the expression of ras proteins revealed no changes in the pattern of c-ras products and the expression of v-ras only in the KHOS cells. All these data suggest that Te85 and HOS 240S cell lines could represent a human alternative recipient system to rodent cells in studies with oncogenes.
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PMID:Integration and loss of a single v-Ki-ras gene affects tumorigenic potential of human osteosarcoma cells. 283 Oct 97

We report here immunological evidence for the specific association between p53 and hsp72/hsc73 heat shock proteins in a human cell line derived from an osteosarcoma. The same association between p53 and hsp72/hsc73 was observed in HOS-TE85 clone 5 from which the HOS-SL cell line was derived. This association was indicated by the co-immunoprecipitation from HOS-SL of both p53 and hsp72/hsc73 proteins observed with either an anti-p53 monoclonal antibody (PAb421) or an antiserum specifically reacting with hsp72/hsc73 heat shock proteins. Furthermore, Western blot analysis allowed us to show that hsp72/hsc73 proteins did not share an epitope with p53, confirming that the co-immunoprecipitation of p53 and hsp72/hsc73 was attributable to the physical association of the proteins. Data obtained from SDS-PAGE show that the HOS-SL cells expressed two forms of p53 with distinct molecular weights. Both forms contained several species with different isoelectric points ranging between pH 6.0 and 6.5. The data obtained from both 1D and 2D gel analyses consistently show that the p53 proteins involved in the association with hsp72/hsc73 were mainly the species that migrated with the slower mobility in the SDS dimension. The possibility is discussed that the HOS-SL p53 variant forming a complex with hsp72/hsc73 contains an activating mutation for transformation.
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PMID:Specific interaction between a subset of the p53 protein family and heat shock proteins hsp72/hsc73 in a human osteosarcoma cell line. 297 69


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