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)

Carbohydrate moieties of cell surface glycoproteins with an external orientation play a role in hormone recognition and/or transmembrane signal transmission. We have examined the effect of various lectins, which interact with specific cell surface glycosyl residues, and of tunicamycin, an antibiotic that inhibits glycosylation of proteins, on the adenosine 3',5'-cyclic monophosphate (cAMP) response to parathyroid hormone (PTH) in confluent cultured osteoblast-like rat osteosarcoma cells (UMR-106) and opossum kidney cells (OK cells). Incubation of both cell lines with wheat germ lectin (WGL), but not with concanavalin A, succinylated wheat germ, ricin, or soybean lectins, markedly reduced the PTH-induced cAMP production, whereas the stimulation obtained with forskolin, a compound that acts directly on the adenylate cyclase enzyme, was not affected. In contrast, tunicamycin did not cause any decrease in the cAMP response to PTH. These results indicate that the masking of sialic acid residue by WGL considerably blunted PTH-stimulated cAMP production in cultured osteoblast-like and kidney cells. An 80% inhibition of glycosylation of cell surface proteins did not appear to affect the response to PTH. Thus the functional role of this carbohydrate moiety in the PTH receptor remains to be determined.
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PMID:Effects of lectins and tunicamycin on cAMP response to parathyroid hormone. 253 32

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 concanavalin A-induced agglutination of cultivated cells of human osteosarcoma Sa-4 was studied in the process of their reversion caused by high polar compounds, dimethylsulphoxide (DMSO) and dimethylformamide (DMFA). Primarily lectin induced an expressed ability to agglutination in Sa-4 cells. In the process of tumour cell reversion under the effect of chemical inducers their agglutination decreases. After the DMSO and DMFA removal the osteosarcoma cells return to their initial state showing a high agglutination. Other high-polar compounds (N-methylformamide and dimethylacetamide) induced no reversion of Sa-4 cells and no agglutination of them as well.
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PMID:[Changes in lectin-induced agglutination of human tumor cells during the process of their reversion]. 385

Laser nephelometry was used to measure the lectin-mediated agglutination of cultured human tumor cells (of osteosarcoma and adenocarcinoma of the lungs). The rates of a decrease in the value of light dispersion (V delta VLD) and the length of time (to) necessary for complete cell sedimentation (at V delta VLD-O) can be used as quantitative indices of cell agglutination. V delta VLD and to were found to correlate with the concentrations of tumor cells and lectins (PHA and Con A).
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PMID:[Estimation of cell agglutination by laser nephelometry]. 658 83

The lectin (PHA and Con A) induced agglutination of a human tumour cell line (lung adenocarcinoma and osteosarcoma) was estimated by the spectrophotometric method. A decrease in the optic density for 1 min (delta D) of cell suspension and the time (t0) necessary for a complete sedimentation of cells (at delta D = 0) were used as quantitative indicators of agglutination. An increase in the concentration of tumour cells and lectins resulted in an increase of delta D and a decrease of t0. The results of spectrophotometry were correlated with the microscopic study data for tumour cells agglutination.
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PMID:[Spectrophotometric method of evaluating tumor cell agglutination induced by lectins]. 659 28

A comparison was made of the cell surface glycoproteins of four human cell lines, namely a giant tumor of bone cell line, an osteosarcoma line, a fibrosarcoma line and a human fibroblast line. The cells were labeled by lactoperoxidase catalyzed iodination and the glycoproteins extracted by 0.5% Triton X-100 were bound to lentil-lectin and subsequently analyzed by SDS gel electrophoresis. While the cell lines examined shared a series of common glycoproteins, it was found that the giant cell tumor line and the fibrosarcoma lines exhibited a higher degree of homology than the other cell lines.
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PMID:Surface glycoproteins of human sarcoma- and fibroblastic cells. 694 38

Sarcoma and normal tissue plasma membrane lectin-reactive glycoproteins were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Two peanut agglutinin-reactive N-acetylgalactosamine-containing glycoproteins of 1.05 x 10(6) and 1.25 x 10(5) Da and one lentil agglutinin-reactive mannose/N-acetylglucosamine(-fucose)/sialic acid-containing glycoprotein of 1.7 x 10(5) Da (Gp170) were detected in osteosarcoma and malignant fibrous histiocytoma (MFH), respectively. However, these glycoproteins were not detected in normal tissue plasma membranes. Concanavalin A, wheat germ and Ulex europaeus Type I agglutinins did not reveal any unique sarcoma-associated membrane glycoproteins. Preliminary studies on monoclonal antibodies (mAbs) generated against Gp170 (mAb 64-35-84) and against lentil-reactive glycoproteins from MFH (mAbs 67-34 and 67-117) revealed high specific binding to a number of membranes isolated from MFH and osteosarcoma tissues, with no crossreactivity to normal human tissues tested (liver, spleen and skin). Detailed analysis of mAb 67-102, which was generated against lentil-reactive glycoproteins isolated from MFH plasma membranes, exhibited significant binding to membranes isolated from osteosarcoma, liposarcoma and MFH; moderate binding to synovial sarcoma, aggressive fibromatosis and fibrosarcoma; and minimal to no binding to other soft tissue sarcoma plasma membranes. No binding was observed to twenty normal tissue specimens, with the exception of low positive binding to two of five fat and two of three colon specimens.
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PMID:Isolation and analysis of lectin-reactive sarcoma-associated membrane glycoproteins. 801 64

The total plasma alkaline phosphatase level has long been recognised as an indicator of osteoblastic activity, but lack of specificity makes it an insensitive index of the progress of disease and the response to treatment. Selective precipitation by wheatgerm lectin allows measurement of the plasma bone-specific alkaline phosphatase. We measured the plasma levels of this isoenzyme in 170 normal Chinese adolescents and adults, in 49 adults with fractures of a long bone, in 15 patients with osteosarcoma and in 38 patients with osteolytic metastases. The enzyme activity was also determined in 39 patients with liver disease. Of the patients with fractures, 94% had increased plasma activity during the healing process. The level was also increased in those with osteosarcoma but not in those with osteolytic bone metastases. There was no significant increase in activity in the patients with liver disease. We conclude that the plasma bone-specific alkaline phosphatase activity is a sensitive and reliable measure of osteoblastic activity.
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PMID:Plasma bone-specific alkaline phosphatase as an indicator of osteoblastic activity. 844 51

Human soluble galactose-binding lectin (galectin-1) has been expressed as an Escherichia coli fusion protein, following the amplification by polymerase chain reaction of cDNA prepared from a human osteosarcoma cell line. The fusion protein is a functional beta-galactoside-binding lectin, as is the recombinant galectin when purified from the cleaved fusion protein. The recombinant galectin has a biphasic effect on cell proliferation. Unlike the fusion protein, it functions as a human cell growth inhibitor, confirming earlier findings with natural human galectin-1, though it is less effective than the natural galectin. This reaction is not significantly inhibited by lactose, and is thus largely independent of the beta-galactoside-binding site. At lower concentrations, recombinant galectin-1 is mitogenic, this activity being susceptible to inhibition by lactose, and thus attributable to the beta-galactoside-binding ability of the protein. Some tumour cells are susceptible to the growth-inhibitory effect, and the galectin-1 gene is expressed in both normal and tumour cells.
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PMID:Biphasic modulation of cell growth by recombinant human galectin-1. 867 36

The levels of bone-specific alkaline phosphatase (BALP) in plasma and tumour tissue samples of 20 Chinese patients with osteosarcoma in Hong Kong were measured by the wheat germ lectin precipitation technique. The plasma BALP levels in these patients were significantly higher than those of the normal subjects (p < 0.001), and also significantly higher than those of patients with benign bone tumor and those of patients with malignant tumor metastasized to the bone (p < 0.0001). Considering the prognostic value of BALP for osteosarcoma, the plasma BALP levels at the time of diagnosis were found to be significantly related to the rate of disease recurrence (p < 0.05). Furthermore, at the time of relapse, the plasma BALP levels in the group of recurrent osteosarcoma patients were significantly higher than those of osteosarcoma patients showing no recurrence (p < 0.05). When ALP was assayed in the tumor tissue, the BALP levels were also significantly higher than those of the control cortical bone extracts in the same group of patients (p < 0.05). We conclude that plasma BALP is a sensitive and specific biochemical parameter in the diagnosis and the subsequent monitoring of osteosarcoma.
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PMID:Bone-specific alkaline phosphatase in plasma as tumour marker for osteosarcoma. 869 30


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