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

The rat osteosarcoma cell line UMR-106-01 has an osteoblast-like phenotype. When grown in monolayer culture, these cells transport Pi via a Na(+)-dependent carrier. The Na(+)-Pi cotransport system is stimulated by parathyroid hormone (PTH). Because there are insulin receptors on osteoblast-like cells, we determined possible effects of insulin on Na(+)-Pi cotransport in UMR-106-01 cells. Incubation of cells with 10(-8) M insulin for 3 h produced a 73% increase (P less than 0.025) in Na(+)-Pi cotransport. There was no significant change in Na(+)-L-alanine cotransport or in Na(+)-independent uptake of Pi and alanine. The stimulatory action of insulin on Na(+)-Pi cotransport was present within 2 h and was dose dependent in the range 10(-10) to 10(-7) M. The increase in Na(+)-Pi cotransport was accompanied by an increase in apparent maximal velocity with no change in apparent Michaelis constant for Pi. Use of cycloheximide to block de novo protein synthesis did not interfere with this action of insulin. We conclude that insulin, like PTH, directly stimulates the Na(+)-Pi cotransport system in osteoblast-like cells. The mechanism remains to be determined.
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PMID:Insulin stimulates sodium-dependent phosphate transport by osteoblast-like cells. 203 31

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

It has been shown that a significant correlation is seen when the hydropathy scores of amino acids encoded by the coding strand of double-helical DNA are plotted against those of the noncoding strand. Thus, peptides encoded by complementary DNA strands might form amphiphilic structures and bind one another. We have used this approach to study the interaction between fibronectin (FN) and its cell receptor. Taking into consideration the nucleotide sequence from published rat cDNA clones that corresponds to the cell binding site (Arg-Gly-Asp-Ser) in the FN molecule, the deduced amino acid sequence found for the putative receptor binding site was Trp-Thr-Val-Pro-Thr-Ala. This peptide was chemically synthesized and coupled to an AH-Sepharose column. FN bound appreciably to this column and was eluted much more efficiently by a solution of Arg-Gly-Asp-Ser-containing peptide than by a solution of related but inactive Arg-Gly-Glu-Ser-containing peptide. Binding of labeled FN to receptor-rich MG63 human osteosarcoma cells was inhibited by the hexapeptide. The hexapeptide Gly-Ala-Val-Ser-Thr-Ala predicted similarly from the nucleotide sequence of human FN was equally efficient in such inhibition. Antibodies produced against Trp-Thr-Val-Pro-Thr-Ala recognized with equal efficiency Gly-Ala-Val-Ser-Thr-Ala in an ELISA assay. Furthermore, they were able to recognize a single 140-kDa band in whole-cell extracts from Chinese hamster ovary cells, attesting to their specificity. Identification of the recognized protein was provided by showing that this antibody was also able to bind to affinity-purified FN receptor from human osteosarcoma MG63 cells.
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PMID:Characterization of the cellular receptor for fibronectin through a hydropathic complementarity approach. 296 29

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

Alpha-aminoisobutyric acid (AIB), or alpha-methyl alanine, is a nonmetabolized amino acid transported into cells, particularly malignant cells, predominantly by the 'A' amino acid transport system. Since it is not metabolized, [1-11C]-AIB can be used to quantify A-type amino acid transport into cells using a relatively simple compartmental model and quantitative imaging procedures (e.g. positron tomography). The tissue distribution of [1-11C]-AIB was determined in six dogs bearing spontaneous tumors, including lymphosarcoma, osteogenic sarcoma, mammary carcinoma, and adenocarcinoma. Quantitative imaging with tissue radioassay confirmation at necropsy showed poor to excellent tumor localization. However, in all cases the concentrations achieved appear adequate for amino acid transport measurement at known tumor locations. The observed low normal brain (due to blood-brain barrier exclusion) and high (relative to brain) tumor concentrations of [1-11C]-AIB suggest that this agent may prove effective for the early detection of human brain tumors.
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PMID:Evaluation of [1-11C]-alpha-aminoisobutyric acid for tumor detection and amino acid transport measurement: spontaneous canine tumor studies. 397 10

Leukocyte interferon was given by i.m. injection as adjuvant therapy to 9 patients with osteosarcoma. The dose was 3 X 10(6) standard units daily for one month, and then 3 times a week for the next 17 months. Blood samples were drawn at intervals for a number of routine tests during the 18-month course of interferon administration and during the subsequent 18 months. On withdrawal of the interferon treatment, the mean Hb concentration rose significantly and the mean ESR fell significantly. There was no significant change in the leukocyte and platelet counts or in the alkaline phosphatase, alanine and aspartate aminotransferase or plasma protein levels.
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PMID:Effect of long-term treatment with human leukocyte interferon on various laboratory parameters. 615 78

A human p53 mutant, p53Val-138 (amino acid 138, Alanine-->Valine), generated by in vitro mutagenesis was introduced into Saos-2 human osteosarcoma and Jurkat acute T-lymphoblastic leukemia cell lines, both lacking p53 protein expression. p53Val-138 caused growth arrest in Saos-2 cell line and apoptosis in Jurkat cell line at 32.5 degrees C while it allowed both cell lines to grow continuously at 37.5 degrees C. p53Val-138 activated expression of p53-responsive genes including MDM2, GADD45 and WAF1/CIP1/SD11 in Saos-2 cell line upon the temperature shift-down from 37.5 degrees C to 32.5 degrees C. Thus, p53Val-138 acted as a temperature-sensitive p53 mutant. Taking advantage of these human cell systems, we demonstrated that p53-mediated cell cycle arrest occurred in G1 and G2/M phases of Saos-2 cell line but not in Jurkat cell line. The induced level of WAF1/CIP1/SDI1 mRNA by p53 was extremely lower in Jurkat cell line than that of Saos-2 cell line. However, MDM2 mRNA accumulated to the similar levels in these two cell lines. These results suggest that a factor(s) other than p53 may be involved in differential expression of WAF1/CIP1/SDI1 and MDM2 mRNA.
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PMID:A human temperature-sensitive p53 mutant p53Val-138: modulation of the cell cycle, viability and expression of p53-responsive genes. 762 16


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