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)

Sarcolectins are present in a great variety of tissues from mammalian origin. Such substances were observed to be secreted from cultures of human embryonic fibroblasts, human osteosarcoma and rat Rous sarcoma transformed cells and could be extracted from TG 180 Crocker Sarcoma or normal human placenta. All sarcolectins tested here, were comparable by their physicochemical properties to those previously reported in hamster or human sarcomas. Indeed, they are proteins or glycoproteins, resistant to pepsin and migrate in SDS-PAGE in the 65 kDa area. They agglutinate cells with an affinity for simple sugars and degrade previously established interferon-induced antiviral resistance. Considering the hamster sarcolectin as reference in this comparative study, both differences and similarities in the antigenic properties of mouse, rat and human sarcolectin variants were demonstrated. An indirect immunofluorescence assay showed that sarcolectins were specifically labelled on the cell surface but not detected in the cytoplasm after methanol or acetone permeabilization of the membrane. By electron microscopy, using immunoperoxidase labelling, sarcolectins can be localized on the surface of normal, transformed, human or rat cells. Only limited segments of normal cell membranes were labelled, while transformed cells were frequently stained on their whole surface. Other known extracellular proteins, such as fibronectin and collagen, did not share common antigenic determinants with sarcolectins.
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PMID:Cell distribution and antigenic properties of mammalian sarcolectins. 311 55

Synthesis of type I and III collagens has been examined in MG-63 human osteosarcoma cells after treatment with the steroid hormone, 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3). Analysis of total [3H]proline-labeled proteins and pepsin-derived collagens revealed that 1,25-(OH)2D3 selectively stimulated synthesis of alpha 1I and alpha 2I components of type I collagen after 6-12 h. Consistent with previous reports (Franceschi, R. T., Linson, C. J., Peter, T. C., and Romano, P. R. (1987) J. Biol. Chem. 262, 4165-4171), parallel increases in fibronectin synthesis were also observed. Hormonal effects were maximal (2- to 2.5-fold versus controls) after 24 h and persisted for at least 48 h. In contrast, synthesis of the alpha 1III component of type III collagen was not appreciably affected by hormone treatment. Of several vitamin D metabolites (1,25-(OH)2D3, 25-dihydroxyvitamin D3, and 24R,25-dihydroxyvitamin D3) tested for activity in stimulating type I collagen synthesis, 1,25-(OH)2D3 was found to be the most active. Analysis of collagen mRNA abundance by Northern blot hybridization indicated that both types I and III procollagen mRNAs were increased 4-fold after a 24-h exposure to 1,25-(OH)2D3. Pro alpha 1I mRNA remained elevated through the 48-h time point while pro alpha 2I and pro alpha 1III mRNAs returned to control values. These results indicate that the regulation of collagen synthesis by 1,25-(OH)2D3 is complex and may involve changes in translational efficiency as well as mRNA abundance. 1,25-(OH)2D3 also caused at least a 20-fold increase in levels of the bone-specific calcium-binding protein, osteocalcin. These results are consistent with the hypothesis that 1,25-(OH)2D3 is stimulating partial differentiation to the osteoblast phenotype in MG-63 cells.
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PMID:Regulation of type I collagen synthesis by 1,25-dihydroxyvitamin D3 in human osteosarcoma cells. 326 82

The FBJ osteosarcoma (a virus-induced osteosarcoma named after its discoverers, Finkel, Biskis, and Jinkins) contains an extensive extracellular matrix. Collagens were extracted by digestion with pepsin in dilute acetic acid from tumors grown in lathyritic mice and fractionated by differential salt precipitation, yielding five fractions. Fraction 1 (precipitated at acidic 0.7 M and neutral 2.0 M NaCl) gave rise mainly to alpha 1(III) chain on phosphocellulose column chromatography. The alpha 1(III) chain was identified by its typical behavior on interrupted electrophoresis and analysis of the CNBr-cleaved peptides. The alpha 1(III) chain of the FBJ tumor had a high content of hydroxylysine and neutral saccharide. Fraction 2 (precipitated at acidic 0.7 M and neutral 4.5 M NaCl) yielded alpha 1(I) and alpha 2(I) chains on the phosphocellulose column from which alpha 1(I) was eluted as a broad peak, conceivably reflecting a high content of hydroxylysine and neutral saccharide. Fraction 4 (precipitated at acidic 1.2 M and neutral 4.5 M NaCl) yielded type V collagen, which also featured an exceptionally high content of neutral saccharide (Yamagata, S., et al. (1982) Biochem. Biophys. Res. Commun. 105, 1208-1214). The proportions of type I, type I trimer, type III, and type V collagens extracted by pepsin digestion from FBJ tumor were calculated to be 33, 29, 26, and 12%, respectively. The FBJ tumor is free from invasion by blood vessels, shows no deposition of calcium, and thus has the appearance of cartilage. But type II collagen, a specific gene product of cartilage, could not be identified in any of the fractions analyzed. Contrary to its appearance, collagen type analyses indicate that FBJ osteosarcoma is literally induced from osteogenic cells.
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PMID:FBJ virus-induced osteosarcoma contains type I, type I trimer, type III as well as type V collagens. 659 19

The composition of collagen was analyzed and the degree of lysyl hydroxylation of individual collagen chains was determined in four osteosarcomas and two osteofibrous dysplasias. In addition, the tumor proliferation (number of mitoses, proliferating-nuclear-antigen-positive cells, MIB) as well as the response to chemotherapy (morphological regression grade) were checked. All tumors contained a high proportion of collagen III and, in all but one osteosarcoma, pepsin-extracted collagens I and III were overmodified. Furthermore, the proportion of diglycosides in collagen I was about four times higher than in controls. The collagen composition and modification resembled those of bones at early stages of human development. One osteosarcoma and both osteofibrous dysplasias were in the normal range of lysyl hydroxylation. There was no correlation between the collagen properties and the histopathological marker of tumor proliferation.
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PMID:Composition and posttranslational modification of individual collagen chains from osteosarcomas and osteofibrous dysplasias. 763 71