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)

The bone inducing factor derived from BF osteosarcoma was purified in the following manner. Step 1. The sarcoma, grown in CBA mice, was excised and lyophilized. Step 2. The powder was washed with chilled acetone. Step 3. The acetone-treated powder was then homogenized with chilled distilled water. Step 4. Washing with 0.15M KCl. Step 5. The precipitate was incubated in in 0.2 N NH2OH, pH7.0, for 48 H at 25 degrees. After Step 5, the bone-forming activity showed a slight increase; however, the factor remained insoluble. The properties of the factor were as follows. The factor is relatively relatively heat stable; the osteogenic activity survived the treatment at 75 degrees for 15 min or at 55 degrees for 19 h. The activity was easily lost by mechanical shaking. Incubation with DNase, RNase, neuraminidase, chondroitinase ABC and beta-galactosidase left the osteogenic activity intact, but treatment with either pronase or collagnease destroyed this activity. The results suggest that the factor may be a protein. The activity was seen with the lyophilized BF osteosarcoma cells (without matrix), and it is probable that the factor was exclusively synthesized in the cells. The bone formation, observed across a millipore filter when living BF osteosarcoma enclosed in a millipore chamber was implanted in mice, suggests the synthesis and secretion of the factor from the cells.
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PMID:Studies on a factor responsible for new bone formation from osteosarcoma in mice. 105 58

A transplantable murine osteosarcoma is described. Following transplantation into a syngeneic mouse the tumor grows rapidly and kills the mouse with pulmonary metastases simulating human osteosarcoma. A cell-mediated antibody response is evoked in the host mouse as demonstrated by in vivo and in vitro tests. The number of pulmonary metastases may be decreased with adjunctive immunotherapy following excision of the primary tumor. Immunotherapeutic materials include BCG and isologous cells treated with Vibrio cholerae neuraminidase.
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PMID:Immunological studies in murine osteosarcoma. Immunogenicity, growth kinetics, and immunotherapy. 106 29

Using a somatic cell hybridization technique, four murine monoclonal antibodies (three immunoglobulin M and one immunoglobulin G3) were produced against a human neuroblastoma cell surface glycolipid antigen. They reacted strongly with all human neuroblastoma tumor-containing specimens and six of eight human neuroblastoma cell lines. More than 98% of each neuroblastoma cell population possessed this surface antigen, and in the presence of complement, 100% of them were killed. While melanoma and osteogenic sarcoma carried this antigen, leukemia and most Ewing's and Wilms' tumors did not. There was no cross-reaction with 30 normal or remission bone marrow samples and none with normal human tissues other than neurons in vitro. This antigen was neuraminidase sensitive, separable on thin-layer chromatogram, and did not modulate after combining with the monoclonal antibodies. These antibodies could detect less than 0.1% tumor cells deliberately seeded in the bone marrow samples. Because of their unique properties, these monoclonal antibodies may have diagnostic and therapeutic potentials.
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PMID:Monoclonal antibodies to a glycolipid antigen on human neuroblastoma cells. 258 Jun 25

In the preceding article, we described physicochemical and kinetic properties of parathyroid hormone (PTH) receptors in clonal rat osteosarcoma cells (ROS 17/2.8) using photoaffinity ligand labeling and showed that the physiologically relevant receptor-ligand complex has an apparent Mr = 80,000. In this study, the photoaffinity labeled Mr = 80,000 receptor was localized exclusively on the cell surface plasma membrane and its glycoprotein nature was demonstrated through the use of lectin affinity-chromatography and specific exo- and endoglycosidases. Rinsing ROS cells, preincubated in the dark with 125I-labeled [Nle8, N-epsilon-(4-azido-2-nitrophenyl)Lys13,Nle18,Tyr34]bovine PTH-(1-34)-NH2 (NAP-NlePTH) (4 h, 15 degrees C, equilibrium conditions) with acidic phosphate-buffered saline (pH 2.5, 30 s, 4 degrees C) before photolysis resulted in selective and nearly total disappearance of the labeled Mr = 80,000 receptor. PTH receptor integrity to acid rinsing and photolysis was shown by relabeling the Mr = 80,000 receptor after a second incubation of these cells with 125I-labeled NAP-NlePTH, followed by photolysis. Adsorption of Triton X-100-solubilized, 125I-labeled NAP-NlePTH receptors to wheat germ agglutinin-agarose is nearly complete and highly selective, and elution with N-acetylglucosamine resulted in virtually total recovery of the labeled receptors from the column. The wheat germ agglutinin-retarded PTH receptors show increased electrophoretic mobility upon treatment with neuraminidase which was inhibited by simultaneous addition of 2,3-dehydro-3-desoxy-N-acetylneuraminic acid, a specific neuraminidase inhibitor. Endoglycosidase F treatment of the Mr = 80,000 receptors generated a single, labeled polypeptide with a Mr = 59,000 which migrated as a narrow band. PTH receptors on ROS 17/2.8 cells appear to be monomeric plasma membrane glycoproteins with an apparent Mr of 80,000 which contain a Mr = 59,000 polypeptide backbone and a polymeric arrangement of N-acetylglucosamine with N-acetylneuraminic acid as major terminal sugar residues.
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PMID:Parathyroid hormone receptors are plasma membrane glycoproteins with asparagine-linked oligosaccharides. 283 Dec 9

The distribution of cell surface negatively-charged macromolecules was determined electron microscopically on untreated and on retinoic acid (RA)-treated cultured human osteosarcoma Hs791 and chondrosarcoma Hs705 cells using cationized ferritin (CF), an electron-dense marker of anionic sites. Labeling on the surface of prefixed cells was continuous and uniform whether they were grown in the absence or presence of RA. In contrast, CF distribution on unfixed cells was markedly affected by RA; CF labeling of untreated cells occurred in patches and clusters whereas the label on RA-treated cells was continuous, as on prefixed cells. CF labeling of unfixed cells decreased considerably after incubation of the cells either with hyaluronidase or neuraminidase. There was also a reduction in patching and clustering. Changes induced by RA in the apparent membrane microviscosity, in neuraminidase-releasable sialic acid, or in transglutaminase activity could not be related to the effect of RA on CF-induced anionic site redistribution since these characteristics were modulated differently in the two cell lines. In contrast, RA increased the sialylation of specific cell surface membrane glycoproteins on both cell types. These results suggest that RA prevents redistribution of cell surface sialoglycoconjugates and glycosaminoglycans by CF. This effect may be the result of increased sialylation of specific surface components and may be related causally to the suppression of the transformed phenotype in the sarcoma cells.
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PMID:Prevention by retinoic acid of anionic site redistribution on the surface of cultured human sarcoma cells. 615 8

The effect of beta-all-trans-retinoic acid (RA) on the synthesis of cellular, cell surface, and secreted glycoconjugates by human Hs705 chondrosarcoma and Hs791 osteosarcoma cells was investigated in vitro. Untreated and RA-treated cells were labeled either metabolically with radioactive precursors or by oxidation of externally exposed cell membrane glycoprotein(s) (GP) by treatment with NalO4 or neuraminidase and galactose oxidase followed by reduction with NaB[3H]4. The cells were solubilized and analyzed by polyacrylamide gel electrophoresis followed by fluorography. RA enhanced the labeling of sialic acid and galactose residues on the GP of relative molecular weight(s) (Mr) in the range 95,000-300,000 on the surfaces of both cell types. [3H]glycosamine incorporation into GP with Mr of 100,000, 150,000, and 190,000 in both cell lines was also stimulated. In the Hs705 cells there was also an increase in the labeling of a 290,000-Mr GP. In contrast, [3H]glucosamine incorporation into glycoconjugates greater than 400,000 Mr in both the cells and the conditioned medium of Hs705 cells decreased. The latter glycoconjugates were susceptible to hyaluronidase and chondroitinases. [3H]glucosamine incorporation into a secreted 230,000-Mr GP, identified as fibronectin, was also reduced. Analyses of conditioned media of cells labeled with [35S]methionine or [14C]proline demonstrated that RA decreased the secretion of procollagen chains and fibronectin. Immunofluorescence revealed that RA alters the distribution of cell-associated fibronectin. These results demonstrated that RA increases the glycosylation of specific cellular and cell surface GP and decreases the production of secreted GP and glycosaminoglycans by the sarcoma cells.
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PMID:Modulation by retinoic acid of cellular, surface-exposed, and secreted glycoconjugates in cultured human sarcoma cells. 658 9

The murine monoclonal antibody 791T/36 cross-reacts with cells other than the immunizing osteogenic sarcoma cell line 791T, upon which the 791T/36-defined epitope is expressed on a protein of apparent molecular weight 72,000. An investigation was performed to determine whether the epitope occurred on similar molecules on other cell lines. Radiolabelled immunoprecipitates, prepared with the 791T/36 antibody, from three osteogenic sarcoma cell lines (2 OS, 788T and 278T), the prostate carcinoma EB33 and the colon carcinoma HcLo each contained a protein with a molecular weight of 72,000 as the major constituent, together with, in some cases, material of lower molecular weight. This heterogeneity was shown by neuraminidase treatment of the immune precipitates to be due to variations in sialic acid content of the antigens since, in five of the six cell lines tested, such treatment produced homogeneous material of apparent molecular weight 55,000. Chymotrypsin treatment of the immune precipitates produced in each instance a major polypeptide of molecular weight 47,000 which displayed no microheterogeneity. Immunoadsorbent-purified antigen from 791T cells was shown to bind strongly to Sepharose-wheat-germ agglutinin and less to Sepharose-concanavalin A, confirming the glycoprotein nature of this antigen. These studies demonstrate that molecules expressing the 791T/36-defined epitopes on different tumour cell lines are glycoproteins which display heterogeneity with respect to apparent molecular weight that is attributable to varying degrees of sialylation. No apparent differences were detected in the polypeptide "backbone" of these antigenic molecules.
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PMID:Analysis of a human osteogenic sarcoma antigen and its expression on various human tumour cell lines. 658 12

Five paired human cell lines consisting of either skin fibroblasts or tumor obtained from patients with osteogenic sarcoma were studied for their susceptibility to macrophage mediated cytotoxicity. In two of the matched pairs, the malignant cell lines were susceptible to the effects of cytotoxic macrophages, whereas normal targets were not. In two other pairs, both malignant and normal targets were resistant to the effects of cytotoxic macrophages. In the fifth pair, both targets were sensitive to the effects of the macrophages. Cell surface sialic acid content of the five matched pairs and several previously studied targets was determined. It was found to correlate with susceptibility to macrophage mediated cytotoxicity. The resistant normal cell lines contained approximately 50% less sialic acid than did the sensitive tumor cell lines. Furthermore, the three resistant tumor lines also had cell surface sialic acid content in the range of the normal resistant targets. Sensitive tumor cells with high cell surface sialic acid, after neuraminidase treatment, became resistant to the effects of cytotoxic macrophages and the effect of the neuraminidase treatment was blocked by addition of sialic acid to the incubation mixture. Thus, it appears that susceptibility to macrophage mediated cytotoxicity is associated with increased levels of sialic acid on the cell surface membranes.
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PMID:Specificity of macrophage mediated cytotoxicity: role of target cell sialic acid. 695 42

High-performance liquid chromatography (HPLC) separates three human bone alkaline phosphatase (BALP) isoforms in serum; two major BALP isoforms, B1 and B2, and a minor fraction, B/I, which is composed on average of 70% bone and 30% intestinal ALP. The current studies were intended to identify an in vitro source of the BALP isoforms for physical, biochemical, and immunological characterizations. The three BALP isoforms were identified in extracts of human osteosarcoma (SaOS-2) cells, by HPLC, after separation by anion-exchange chromatography. All three BALP isoforms were similar with respect to freeze-thaw stability, solubility, heat inactivation, and inhibition by L-phenylalanine, L-homoarginine, and levamisole. The isoforms were also kinetically similar (i.e., maximal velocity and KM at pH 8.8 and pH 10.0). The isoforms differed, however, with respect to sensitivity to precipitation with wheat germ agglutinin (WGA), P < 0.001, but not Concanavalin A. At 3.0 mg/ml, WGA precipitated approximately 25% of B/I but more than 80% of B1 and B2. Molecular weights were estimated by native gradient gel electrophoresis: B/I, 126 kDa; B1, 136 kDa; and B2, 141 kDa. Desialylation with neuraminidase reduced the apparent sizes of B1 and B2 to 127 kDa (i.e., approximately to that of B/I). The total carbohydrate content was calculated to be 18 kDa, 28 kDa, and 33 kDa (i.e., 14%, 21%, and 23%) for the BALP isofonns, B/I, B1, and B2, respectively. The number of sialic acid residues was estimated to be 29 and 45, for each B1 and B2 homodimer, respectively. Apparent discrepancies between these estimates of molecular weight and estimates based on gel filtration chromatography were attributed to nonspecific interactions between carbohydrate residues and the gel filtration beads. All three BALP isoforms showed similar dose-dependent linearity in the commercial Alkphase-B and Tandem-MP Ostase immunoassays, r = 0.944 and r = 0.985, respectively (P < 0.001). In summary, our data indicate that B1 and B2 have more (or more reactive) sialic acid residues compared with B/I, which mainly explains the apparent differences in molecular weight. Future investigations will focus on the clinical and functional significance of the revealed differences in sialic acid residues.
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PMID:Differences in sialic acid residues among bone alkaline phosphatase isoforms: a physical, biochemical, and immunological characterization. 1223 76

Nineteen monoclonal antibodies (MAbs) against tissue-nonspecific (liver/bone/kidney) alkaline phosphatase (TNALP) were investigated in the ISOBM TD-9 Workshop. These MAbs were generated with antigens obtained from human bone tissue (n = 9), human osteosarcoma cell lines (SaOS-2 and TPX; n = 7) and human liver tissue (n = 3). The evaluation included the following antigen forms: (a) commercially available preparations of human bone ALP (BALP) and liver ALP (LALP); (b) human BALP isoforms, B/I, B1 and B2; and (c) soluble secreted epitope-tagged recombinant human TNALP (setTNALP) expressed in COS-1, osteosarcoma (SaOS-2) and hepatoma (Huh2) cell lines. In addition, 16 TNALP mutant cDNAs corresponding to a wide spectrum of reported hypophosphatasia mutations were used in an attempt to map specific immunoreactive epitopes on the surface of the TNALP molecule. The TD-9 MAbs were evaluated by immunoradiometric (IRMA) assays, cross-inhibition and different enzyme immunoassay designs. No indications of explicit tissue discriminatory immunoreactivities of the investigated MAbs against TNALP were found. However, certain IRMA combinations of MAbs increased the specificity of BALP measurements. All MAbs bound to the three BALP isoforms B/I, B1 and B2, but none of the investigated MAbs were specific for any of the isoforms. Significant differences were, however, found in immunoreactivity between these isoforms, with cross-reactivities ranging from 21 to 109% between the two major BALP isoforms B1 and B2. Desialylation with neuraminidase significantly increased the MAb affinity for the BALP isoforms B/I, B1 and B2, and also decreased the observed differences in cross-reactivity between these isoforms. We suggest, therefore, that the MAb affinity is dependent on the amount/number of terminal sialic acid residues located at the five putative N-glycosylation sites. Based on the overall results, we present a putative three-dimensional model of the TNALP molecule with positioning of the four major antigenic domains (designated A-D) of the investigated MAbs. The TNALP molecule is depicted as a homodimer, hence most, but not necessarily all, epitopes are displayed twice. The antigenic domains were positioned with the following assumptions: domain A was positioned close to the active site since most of these MAbs interfered with the catalytic activity. Interestingly, both MAbs included in the commercial BALP kits were grouped with domain A. Moreover, 4 of the 5 putative N-glycosylation sites (with terminal sialic acid residues) are located within, or with close proximity to, domain A. Domain B was localized at the top flexible loop (crown domain) of the TNALP molecule. Domain C was clearly defined by the IRMA assay combinations and by site-directed mutants of TNALP to be close to residue E281, which is located near the fourth metal binding site, likely to be occupied by a calcium ion. Domain D was positioned close to residues A115, A162 and E174, but this domain was also close to the GPI anchor site. In conclusion, none of the 19 investigated TD-9 MAbs were entirely specific for BALP or LALP, thus indicating that all MAbs bind mainly to epitopes on the common protein core of BALP and LALP and/or common glycosylated epitopes. However, some MAbs (either single or in combination with other MAbs) work sufficiently well to measure BALP when the assayed samples do not contain elevated levels of LALP.
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PMID:Monoclonal antibodies against tissue-nonspecific alkaline phosphatase. Report of the ISOBM TD9 workshop. 1249 79


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