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)

Alkaline phosphatase (orthophosphoric-monoester phosphohydrolase [alkaline optimum], EC 3.1.3.1) expressed in two human osteosarcoma cell lines (Saos-2 and KTOO5) in culture was the tissue nonspecific type and was released from the plasma membrane by phosphatidylinositol (PI) phospholipase C. Despite a difference of 10-fold between the two cell lines in the amount of alkaline phosphatase expressed, the phospholipase solubilized nearly all of the phosphatase from resuspended cells of the two lines. Alkaline phosphatase released with Nonidet-P40 from Saos-2 cells had a Mr of 445,000 by gradient gel electrophoresis in the absence of detergent; that released by PI-phospholipase C was 200,000. The subunit Mr of both solubilized forms was 86,000. Thus, tetrameric alkaline phosphatase in the membrane is attached by a PI-glycan moiety and is converted to dimers when released by PI-phospholipase C. Tunicamycin treatment of Saos-2 cells in culture affected the release of alkaline phosphatase by a high concentration of PI-phospholipase C, but not by a low concentration; both the rate and extent of release were lower from treated cells. However, the enzyme released from the treated cells was in two forms with different molecular weights; it seems that both glycosylated and nonglycosylated dimers were transported to the cell surface and incorporated into the plasma membrane. Glycosylation does not appear to be necessary for alkaline phosphatase to be anchored in the membrane via PI.
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PMID:Release of alkaline phosphatase from human osteosarcoma cells by phosphatidylinositol phospholipase C: effect of tunicamycin. 316 62

Gardner's murine osteosarcoma has been successfully cultured and maintained as a clonal cell line (GOS/T), capable of forming a tumor with neoplastic bone and osteoid tissue by inoculation of 1 x 10(7) cultured cells. Alkaline phosphatase (ALPase) level in the culture medium and the serum from the tumor-bearing mice increased significantly three times and 16 to 105 times, respectively. The bone-specific ALPase was purified by butanol extraction following gel-filtration through Sephadex G-200. The molecular weight of ALPase was determined as 420,000, which was three times 140,000, the molecular weight of a subunit. Immunofluorescence staining using anti-ALPase antiserum, which was made by inoculation of partially purified ALPase, revealed a positive reaction for GOS/T cell line and osteoblasts of the fetal mice. The data presented here suggest that the cell line of GOS/T can be regarded as an established cell line, and the immunological reaction with anti-ALPase antibody is a useful model system to study human osteosarcoma.
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PMID:Establishment and characterization of a murine Gardner's osteosarcoma cell line (GOS/T): purification of bone-specific alkaline phosphatase (ALPase) and use of anti-ALPase as a diagnostic acid. 322 88

The molecular nature of an osteosarcoma-associated antigen was investigated with the three monoclonal antibodies Ost6 (immunoglobulin (IgG1), Ost7 (IgG1), and Ost15 (IgG2a), which selectively react with frozen sections of osteosarcoma and chondrosarcoma tissues. When tested with a panel of 41 human cell lines in the mixed hemadsorption assay, the antibodies reacted similarly with three of six osteosarcomas, one choriocarcinoma, one teratoma, and one osteoblast-like culture, but failed to react with 32 lines of normal and other tumor cell types. Immunoprecipitation plus sodium dodecyl sulfate (SDS)--polyacrylamide gel electrophoresis and sequential immunoprecipitation studies revealed that in [35S]methionine- or [14C]glucosamine-labelled osteosarcoma cells the three antibodies detected a single glycoprotein, with an apparent molecular mass of 86 kilodaltons (kDa), which was not affected by reducing conditions. Tunicamycin treatment and pulse-chase experiments showed glycosylation of this molecule to be N-linked; it arose from a 54-kDa polypeptide precursor. Alkaline phosphatase activity was detected in the material rich in 86-kDa molecules that was immunoprecipitated from serologically reactive cell lines with each antibody. These antibodies also cross-reacted with two isoenzymes of alkaline phosphatase (strongly with the liver and bone, and moderately with the placental isoenzyme), but not with the intestinal form.
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PMID:Identification of a human osteosarcoma-associated glycoprotein with monoclonal antibodies: relationship with alkaline phosphatase. 333 Dec 86

Alkaline phosphatase [ALP; orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1] is a ubiquitous enzyme of unknown function expressed at high levels in cells of mineralizing tissues. To study the structure, function, and expression of ALP, a full-length cDNA of rat ALP (2415 bases) was isolated from a ROS 17/2.8 osteosarcoma cell lambda gt10 cDNA library. The predicted amino acid sequence spans 524 residues and includes an N-terminal signal peptide of 17 amino acids, the phosphohydrolase active site, a rather hydrophilic backbone with five potential N-glycosylation sites, and a short hydrophobic C-terminal sequence. ALP negative CHO cells transfected with an expression vector containing the ALP coding sequences express ALP. The rat bone, liver, and kidney ALP shows remarkable 90% homology with the corresponding human enzyme, the most divergent region being the C-terminal hydrophobic domain through which the enzyme may be anchored to the plasma membrane. The rat ALP also shows 50% homology with the human placental and intestinal ALP and 25% homology with the Escherichia coli ALP. The amino acids involved in catalysis show nearly complete homology among all known ALP sequences, suggesting that these enzymes evolved from a common ancestral gene. The rat ALP cDNA pRAP 54, used as a hybridization probe in RNA blot analysis of several tissues that express ALP, revealed the presence of an ALP mRNA of approximately equal to 2500 bases. Furthermore, hybridization patterns derived from Southern blot analysis of rat chromosomal DNA offered molecular evidence that the ALP expressed in ROS 17/2.8 osteosarcoma and various rat tissues, excluding the intestine, is the product of the same single copy gene.
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PMID:Structure and expression of rat osteosarcoma (ROS 17/2.8) alkaline phosphatase: product of a single copy gene. 342 31

Alkaline phosphatase (AP) was purified to over 90% homogeneity from rat osteosarcoma by acetone precipitation followed by chromatography on DEAE-cellulose, Sephacryl S-200, and hydroxyapatite. The purified enzyme had a specific activity of 759 units/mg protein at its optimal pH (10.5), and a Km of 0.8 mM for p-nitrophenylphosphate. The enzyme's apparent subunit molecular mass on sodium dodecyl sulfate-polyacrylamide gel electrophoresis was 82,000 Da. The heat-inactivation profile and homoarginine inhibition were characteristic of the bone-liver-kidney AP isoenzyme. Monoclonal and polyclonal anti-AP antibodies were prepared and characterized. Polyclonal rabbit antiserum quantitatively precipitated the activity from purified AP preparations and tissue extracts but did not inhibit AP catalytic activity. This antiserum was almost 10-fold less active against heat-inactivated enzyme when tested in a competition assay using 125I-AP. Two distinct monoclonal antibodies were each partly effective in immunoprecipitating AP when tested individually; however, together they precipitated over 90% of the AP activity.
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PMID:Rat alkaline phosphatase. I. Purification and characterization of the enzyme from osteosarcoma: generation of monoclonal and polyclonal antibodies. 347 90

A mouse monoclonal antibody raised against rat osteosarcoma alkaline phosphatase (AP) was covalently coupled to protein A-Sepharose and used to purify this enzyme from preparations of rat osteosarcoma, calvaria, kidney, and placenta in a single-step procedure. The tissue-specific isoenzymes purified in this manner showed identity in the immunodiffusion reaction with a polyclonal anti-AP antibody, but differed in apparent molecular weight and degree of polydispersity on sodium dodecyl sulfate-polyacrylamide gels. Treatment with N-glycanase abolished these differences, yielding proteins with an apparent molecular weight of 52,000 Da and identical V8 protease digestion patterns. Alkaline phosphatase from these tissues showed no significant difference in amino acid composition and identity in the first 20 N-terminal amino acids. These findings provide structural evidence which supports the hypothesis that the tissue-specific alkaline phosphatase isoenzymes share a common protein sequence subject to different glycosylation pattern.
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PMID:Rat alkaline phosphatase. II. Structural similarities between the osteosarcoma, bone, kidney, and placenta isoenzymes. 347 91

Alkaline phosphatases (ALPs) [orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1] isolated from human liver, bone, and kidney (L/B/K) exhibit very similar biochemical and immunologic properties that differentiate them from other human ALPs, such as those characteristically found in placenta and intestine. Despite their similarities, the L/B/K ALPs produced in different tissues show slight physical differences. To examine structural and evolutionary relationships between the various ALPs, a cDNA corresponding to L/B/K ALP mRNA has been isolated. A lambda 11 cDNA expression library was constructed using poly(A) RNA from the osteosarcoma cell line Saos-2 and screened with anti-liver ALP antiserum. The 2553-base-pair cDNA contains an open reading frame that encodes a 524 amino acid polypeptide with a predicted molecular mass of 57.2 kDa. This ALP precursor protein contains a presumed signal peptide of 17 amino acids followed by 37 amino acids that are identical to the amino-terminal sequence determined from purified liver ALP. In addition, amino acid sequences of several CNBr peptides obtained from liver ALP are found within the cDNA-encoded protein. The deduced L/B/K ALP precursor polypeptide shows 52% homology to human placental ALP and 25% homology to Escherichia coli ALP precursor polypeptides. Sixty percent nucleotide homology exists between the human L/B/K and placental cDNAs over the protein coding regions. The 5' and 3' untranslated regions of the L/B/K ALP cDNA, 176 and 805 base pairs, respectively, show no homology to the corresponding regions of placental ALP cDNA.
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PMID:Isolation and characterization of a cDNA encoding a human liver/bone/kidney-type alkaline phosphatase. 353 5

A new technique was applied to the study of human osteosarcoma. Ten slices of 10 micron were cut serially from 2 X 2 X 6 mm shock frozen blocks of human osteosarcoma for chemical analysis. Before and after each series of 10 slices, one slice of 10 micron was separated for morphological analysis. Four different types of osteosarcoma were investigated: Case 1 was an atypical osteoblastic osteosarcoma, case 2 a small cell sclerosing osteosarcoma, case 3 a well-differentiated parosteal osteosarcoma grade I, and case 4 a highly malignant anaplastic osteosarcoma. Alkaline phosphatase, acid phosphatase, beta-glucuronidase and proteolytic activities were analysed as well as matrix collagen and hexosamine, phosphorus (Pi and Po), protein, DNA, and water content. In accordance with the morphology, the obtained data illustrate the great heterogeneity of osteosarcomas. Although case 1, 2 and 3 all represent calcifying types of the tumor, characteristic differences exist with regard to the matrix and the degree of calcification. In contrast to these three, case 4 presents a noncalcified type of osteosarcoma whose matrix contains relatively high amounts of hexosamine and low amounts of collagen, whereas DNA and water contents are high. The data from the analysis of osteosarcoma were compared with previous results from the calf epiphyseal growth plate in order to define differences and similarities between the formation of tumor bone and the physiological formation of hard tissue.
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PMID:Biological characterization of human bone tumors. IV. Combined biochemical and histological analyses of different osteosarcomas. 386 64

Histochemical staining for three hydrolytic enzymes were performed in 35 bone tumours and 43 soft tissue tumours, malignant as well as benign. Osteosarcoma, intra-osseous as well as extra-osseous, revealed characteristic rich staining for alkaline phosphatase, no matter how dedifferentiated the tumour was. Haemangioendothelioma (and normal endothelium), too, showed strong reaction for alkaline phosphatase whereas haemangiopericytoma did not. Alkaline phosphatase furthermore was found in slight to moderate amounts in fibrous proliferations. All other tumours examined were negative. Acid phosphatase was found in almost every tumour investigated except Ewing sarcoma and chondromyxoid fibroma. However, high activity was characteristic of giant cell tumours and malignant fibrous histiocytoma. The inhibition of acid phosphatase by tartrate was complete except in osteosarcoma and giant cell tumours, where only a partial inhibition was seen. There were non-specific esterase reactions in a variety of tumours, but very strong reactions were characteristic of malignant fibrous histiocytoma and giant cell tumours. The reaction could be completely inhibited by the addition of fluoride. In an era of increasing application of immunohistologic techniques in surgical pathology it might be of value to remember that simple enzyme histochemical stainings may provide helpful diagnostic features in the classification of bone and soft tissue tumours.
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PMID:Enzyme histochemical investigations on bone and soft tissue tumours. 398 37

Alkaline phosphatase (AP) has been demonstrated by combined electron microscopy and histochemistry in a transplantable rat osteogenic sarcoma, using a modified Gomori technique (Salomon, 1974). During the early stages of growth of subcutaneously implanted tumors, AP was detected in intracellular membrane systems resembling Golgi and on membranes of cells and matrix vesicles. During growth of the tumor, there was extensive development of intercellular collagen, and AP was demonstrated in bodies associated with collagen. In some cases the AP-containing bodies resembled matrix vesicles, but there was considerable size heterogeneity of the AP-containing bodies, suggesting that there may be heterogeneity of matrix vesicles. The amount of detectable AP seemed to increase in all areas of the tumor which were viable, during tumor growth, but no AP could be detected in cell debris of necrotic areas of the tumor (area C) nor associated with collagen in that area. Area D, particularly during later stages of tumor growth, showed the greatest development of calcium deposits, with calcium spicules apparently associated with AP-containing bodies on both cell membranes and collagen. AP-containing bodies also appeared in large numbers in venules during later stages of tumor growth, associated with an amorphous material. This may account for the increase in serum AP activity which occurs during later stages of growth of transplanted tumors. The sites of AP activity in this osteogenic sarcoma were similar to those described in normal tissue, but generally seemed to be more abundant.
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PMID:An ultrastructural study of alkaline phosphatase in a transplantable rat osteogenic sarcoma. 658 6


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