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 synthesis, purification, and characterization of biotinylated analogues of parathyroid hormone (PTH) and PTH-related protein (PTHrP) are described. A novel methodology was developed which allowed the selective biotinylation during solid-phase synthesis of either the Lys13 or Lys26 residue in PTH/PTHrP sequences. Incorporation of orthogonally protected N alpha-Boc-Lys(N epsilon-Fmoc) at a selected position in the sequence, followed by selective side-chain deprotection and biotinylation of the epsilon-amino group, permitted modification of the specific lysine only. Biotinylated analogues of [Nle8,18,Tyr34]bPTH(1-34)NH2 (analogue 1a) were prepared by modification of Lys13 with a biotinyl group (analogue 1) or a biotinyl-epsilon-aminohexanoyl group (analogue 2) or at Lys26 with a biotinyl-epsilon-aminohexanoyl group (analogue 3). A biotinylated PTHrP antagonist [Leu11,D-Trp12,Lys13(N epsilon-(biotinyl-beta-Ala))]PTHrP(7-34)NH2 (analogue 5), was also prepared. In a different synthetic approach, selective modification of the thiol group of [Cys35]PTHrP(1-35)NH2, in solution, with N-biotinyl-N'-(6-maleimidohexanoyl)hydrazide, resulted in analogue 4. The high affinities of the biotinylated analogues for PTH receptors present in human osteosarcoma B-10 cells or in porcine renal cortical membranes (PRCM), were comparable to those of the underivatized parent peptides. The analogues were also highly potent in stimulation of cAMP formation (analogues 1-4) or inhibition of PTH-stimulated adenylyl cyclase (analogue 5) in B-10 cells. The most potent analogue (analogue 1) had potencies in B-10 cells (Kb = 1.5 nM, Km = 0.35 nM) and in porcine renal membranes (Kb = 0.70 nM) identical or similar to those of its parent peptide, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Synthesis of fully active biotinylated analogues of parathyroid hormone and parathyroid hormone-related protein as tools for the characterization of parathyroid hormone receptors. 131 56

A highly purified fraction with bone-inducing potential was obtained from a murine osteosarcoma using initial fractionation, gel filtration on Sephacryl S-200, and cation-exchange, hydroxyapatite and reverse-phase h.p.l.c. Protein sequencing of the sample derived from this active fraction revealed the N-terminal amino acid sequence to be Ala-Ala-Leu-Arg-Pro-Leu-Val-Lys-Pro, which is identical to the N-terminal sequence of mouse, human and rat ribosomal protein L32, except for an additional methionine residue at the N-terminus of the three latter proteins. Amino acid analysis of the sample also showed its similarity to L32. Two lines of evidence using an antibody specific for the above peptide strongly suggest that this L32-related protein from a murine osteosarcoma has the potential to induce ectopic bone formation. First, the protein specifically detected by the antibody co-distributes with the bone-inducing active fraction. Secondly, a highly purified sample obtained using the antibody was shown to induce the formation of bone with active haematopoiesis.
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PMID:Purification and partial identification of bone-inducing protein from a murine osteosarcoma. 132 Mar 80

A patient with bilateral retinoblastoma and subsequent multiple primary osteosarcomas has been described previously. Osteosarcoma cell lines established from this patient were shown to express a shortened RB1 mRNA transcript and no detectable normal Rb protein. We now show that the osteosarcoma cell lines have lost one TP53 allele and contain a mutation in exon 8 codon 286 [GAA to AAA (Glu to Lys)] in the remaining allele. Consequently, the osteosarcoma cell lines have no normal Rb protein and no normal p53 protein. Neither constitutional DNA nor DNA extracted from a retinoblastoma of the left eye of the patient contained the TP53 mutation, suggesting that the TP53 mutation in the osteosarcoma cells may represent a tumor-promoting mutation, which confers a selective growth advantage. If both RB1 and TP53 are involved in the initiation of osteosarcoma, the mechanisms for development of the retinoblastoma and osteosarcoma tumors are different.
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PMID:A TP53 mutation detected in cells established from an osteosarcoma, but not in the retinoblastoma of a patient with bilateral retinoblastoma and multiple primary osteosarcomas. 133 9

PA-III rat prostate adenocarcinoma cells are capable of inducing osteoblastic reaction after inoculation onto rat skeleton. In this study PA-III cells and osteoblast-derived rat osteosarcoma cells (UMR 106 cells) were employed to characterize the cellular interactions in the PA-III cell-induced bone tumors, in vitro. Insulin-like growth factor-I (IGF-I) and conditioned media (CM) of UMR 106 cells stimlated tritiated-thymidine incorporation into the DNA of PA-III cells growing in serum-free media. This effect was inhibited by monoclonal anti-hIGF-I antibody. In addition PA-III cell CM contained proteinolytic activity for the IGF-binding proteins of UMR 106 cell CM (IGFBP-1 and -2). This proteinase activity hydrolyzed also benzyloxycarbonyl-lysine thiobenzyl ester (BLT) and its action on IGFBPs and BLT was inhibited by benzamidine and aprotinin. Proteinase activity of PA-III cell CM when bound covalently to tritiated-dilsopropylfluoro-phosphate (DFP) and then analyzed on SDS-PAGE gel electrophoresis, revealed the presence of radioactivity linked with a 35 kDa protein band. This proteinase was eluted in the void volume of the G-50 sephadex column and was retained on and eluted from p-benzamidine affinity column. The 35 kDa proteinase was retained on and was eluted from cartridges of the C18 silica by 80% acetonitrile over 0.1% trifuroacetic acid. This partially purified material hydrolyzed BLT substrate and IGFBPs of UMR 106 cell CM and its effect was inhibited by benzamidine and aprotinin. These data indicate that PA-III cell CM contains a 35 kDa proteinase capable of digesting the IGFBPs and thus increases the bioavailability of osteoblast-derived IGFs. This mechanism may participate in the pathophysiology of the PA-III cell-induced bone tumor and its subsequent osteoblastic reaction.
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PMID:Proteinolytic activity against IGF-binding proteins involved in the paracrine interactions between prostate adenocarcinoma cells and osteoblasts. 137 96

To identify the sites important for the different biological activities of human interleukin-1 alpha (hIL-1 alpha), 56 single-amino acid-substituted mutants of hIL-1 alpha were produced in Escherichia coli using site-directed mutagenesis, and were examined for their biological activities such as mouse lymphocyte activating factor activity (LAF activity), cytostatic activity against human melanoma cells A-375 (A375 activity) and prostaglandin E2 (PGE2) inducing activity in human osteosarcoma cells MG-63 (PEI activity). Two amino acid residues, Asp26 and Asp151, were found to be important for these activities. The replacement of Asp26 by Val caused a decrease in LAF and PEI activities by one or two orders of magnitude and a slight decrease in A375 activity. The Tyr or Phe substitution for Asp151 caused decreases in LAF and A375 activities by one or two orders of magnitude and complete loss of PEI activity. The change from Asp151 to Lys or Arg resulted in marked decrease in LAF activity and complete loss of A375 and PEI activities. Since Asp26 and Asp151 are close to each other in the three-dimensional structure, the region involving these amino acids seems to be important for the biological activities of hIL-1 alpha.
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PMID:Structure-activity relationships in human interleukin-1 alpha: identification of key residues for expression of biological activities. 159 72

[Nle8,18,Tyr34]bPTH-(1-34)amide (NlePTH) was biotinylated using sulfosuccinimidyl 6-(biotinamido)hexanoate, in dimethyl sulfoxide, and the multiple resulting peptides peaks were separated by reverse-phase high performance liquid chromatography. Their biological activities were compared with those of NlePTH, the parent compound, in radioreceptor and cAMP accumulation bioassays using rat osteosarcoma 17/2.8 cells; the earliest two eluting products, bioPTH 1 and 2, were equipotent, a third, bioPTH 3, was only 10% as potent, and the remaining, later eluting derivatives all were less than 0.1% as active. Competitive avidin binding assays using [3H]biotin suggested that bioPTH 1 and 2 had a single biotin congener per molecule, while bioPTH 3 contained two biotin residues. Upon Edman degradation, bioPTH 1 contained biotin on the lysine at position 13 of NlePTH; bioPTH 2's biotin was on the lysine at position 26 (or 27) and bioPTH 3 had biotins on lysines at both positions 13 and 26 (or 27). Avidin tagged with 125I, peroxidase, or fluorescein isothiocyanate was detected on bone-derived cells which had been incubated initially with bioPTH 2 (1, 10, and 100 nM) for 4 h, but not when NlePTH (1 microM) was added with bioPTH 2. A fluorescence-activated cell sorter detected a symmetrical shift in fluorescence of bone-derived cells incubated with 10 nM of bioPTH 2 and 10 micrograms/ml fluorescein isothiocyanate-avidin. Addition of a 30-fold molar excess of NlePTH, or omission of bioPTH 2, completely reversed this fluorescence shift, and no shift in fluorescence was seen with cells lacking PTH receptors. This fully active, high affinity biotinylated PTH-derivative should prove useful in the study of PTH receptor-bearing cells.
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PMID:Characterization of fully active biotinylated parathyroid hormone analogs. Application to fluorescence-activated cell sorting of parathyroid hormone receptor bearing cells. 215 27

Inhibitory insulin-like growth factor binding protein (In-IGF-BP) has been purified to homogeneity from medium conditioned by TE89 human osteosarcoma cells by two different methods using Sephadex G-100 gel filtration, FPLC Mono Q ion-exchange, HPLC C4 reverse-phase, HPLC CN reverse-phase, and affinity chromatographies. In-IGF-BP thus purified appeared to be homogeneous and unique by the following criteria. (i) N-terminal sequence analysis yielded a unique sequence (Asp-Glu-Ala-Ile-His-Cys-Pro-Pro-Glu-Ser-Glu-Ala-Lys-Leu-Ala). (ii) Amino acid composition of In-IGF-BP revealed marked differences with the amino acid compositions of other known BPs. (iii) In-IGF-BP exhibited a single band with a molecular mass of 25 kDa under reducing conditions on sodium dodecyl sulfate/polyacrylamide gels. IGF-I and IGF-II but not insulin displaced the binding of 125I-labeled IGF-I or 125I-labeled IGF-II binding to In-IGF-BP. In-IGF-BP inhibited basal, IGF-stimulated bone cell proliferation and serum-stimulated bone cell proliferation. Forskolin increased synthesis of In-IGF-BP in TE85 human osteosarcoma cells in a dose-dependent manner. Based on these findings, we conclude that In-IGF-BP is a protein that has a unique sequence and significant biological actions on bone cells.
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PMID:Isolation of an inhibitory insulin-like growth factor (IGF) binding protein from bone cell-conditioned medium: a potential local regulator of IGF action. 247 22

We have isolated a molecular clone of the full-length integrated provirus of simian acquired immune deficiency syndrome retrovirus serotype 1 (SRV-1) from a fatal case of simian acquired immune deficiency syndrome in a juvenile rhesus macaque. An integrated SRV-1 provirus was cloned, sequenced, and found to contain four large open reading frames encoding gag-precursor protein, protease, polymerase, and envelope. The proviral clone was transfected into D17 canine osteosarcoma cells and found to produce infectious virus. A comparison of the sequences of this clone with a noninfectious clone showed 20 differences, resulting in 10 amino acid changes. Also, a cluster of exchanges, short insertions, and deletions in the 5' leader sequences resulted in extension of the tRNA(Lys) primer-binding site from 14 to 19 nucleotides. Virus isolated from transfected cells was shown to be infectious and pathogenic, resulting in disease that followed the same time course and mortality as disease induced by uncloned, in vitro cultivated virus isolated from diseased animals. These results unequivocally show that a type D retrovirus (SRV-1) causes a fatal immunosuppressive syndrome in rhesus monkeys.
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PMID:Induction of simian acquired immune deficiency syndrome (SAIDS) with a molecular clone of a type D SAIDS retrovirus. 304 Oct 28

Cultured rat osteosarcoma (UMR106) alkaline phosphatase was purified to apparent homogeneity by sequential application of polyclonal antibody affinity, DEAE-cellulose, and Sepharose CL-6B chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the enzyme preparation treated with sodium dodecyl sulfate and mercaptoethanol showed the presence of a dominant band (using silver staining) corresponding to a molecular weight of 80,000. The amino acid composition was similar to those of various alkaline phosphatases. The N-terminal amino acid sequence was determined as follows: Phe-Val-Pro-Glu-Lys-Glu-Lys- Asp-Pro-Ser-Tyr-Trp-Arg-Gln-Gln-Ala-Gln-Glu-Thr-Leu- Lys-Asn-Ala-Leu-Lys-?-Gln-Lys-?-Asn-Val-Asn-Ala-Lys.
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PMID:Purification and partial amino acid sequencing of rat bone tumor (UMR106) alkaline phosphatase. 329 65

Matrix Gla protein (MGP), a low molecular weight protein found in bone, dentin, and cartilage, contains 5 residues of the vitamin K-dependent amino acid gamma-carboxyglutamic acid (Gla). We have used antibodies raised against MGP and oligonucleotide probes to screen a lambda gt11 cDNA library constructed from the rat osteosarcoma cells (line ROS 17/2) that had been pretreated with 1 alpha,25-dihydroxyvitamin D3. By sequencing several cloned cDNAs, we established a 523-base-pair sequence that predicts an 84-residue mature MGP and a 19-residue hydrophobic signal peptide. The 84-residue mature rat MGP predicted from the cDNA sequence has an additional 5 residues at its C terminus (-Arg-Arg-Gly-Ala-Lys) not seen in the sequence of MGP isolated from bovine bone. The structure of rat MGP provides insight into the mechanisms by which the vitamin K-dependent gamma-carboxylase recognizes substrate. The present studies show that MGP, unlike other vitamin K-dependent proteins, lacks a propeptide. The absence of an MGP propeptide demonstrates that gamma-carboxylation and secretion of vitamin K-dependent proteins need not be linked to the presence of a propeptide or to its proteolytic removal. The propeptides of other vitamin K-dependent proteins are structurally homologous, and there is evidence that this homologous propeptide domain is important to substrate recognition by the gamma-carboxylase. Mature MGP has a sequence segment (residues 15-30) that is homologous to the propeptide of other vitamin K-dependent proteins and probably serves the same role in gamma-carboxylase recognition. Rat MGP also has a second sequence that has recently been identified in all known vitamin K-dependent vertebrate proteins, the invariant unit Glu-Xaa-Xaa-Xaa-Glu-Xaa-Cys (EXXXEXC). Since the glutamic residues in this unit are sites of gamma-carboxylation, it has been suggested that the EXXXEXC unit could allow the gamma-carboxylase to discriminate between substrate and product. The demonstration that two structures common to vitamin K-dependent proteins, the homologous propeptides domain and the invariant EXXXEXC unit, are in mature MGP indicates that des-gamma-carboxy-MGP should be an excellent in vitro gamma-carboxylase substrate for analysis of mechanisms involved in substrate recognition and product dissociation.
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PMID:Molecular cloning of matrix Gla protein: implications for substrate recognition by the vitamin K-dependent gamma-carboxylase. 331 5


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