Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0029463 (osteosarcoma)
 16,637 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Monoclonal antibodies against a human osteogenic sarcoma cell line were prepared by production of a somatic cell hybrids between the spleen cells from U-393OS--immunized mice and the mouse myeloma cells SP2/0. From 7 producing and well-growing clones only one--B-0S12--produced antibodies, reactive preferentially with osteosarcoma cells as identified by binding second antibodies and 125I-labeled Protein A. This antibody was tested against a panel of normal and tumor cell targets to determine the pattern of the antigen detected. The monoclonal antibody reacted strongly against U-3930S cells and another human sarcoma in vitro and more weakly against human fibroblasts, peripheral lymphocytes, red blood cells and was negative against mouse fibroblasts. When tested against a panel of unrelated human tumor cell lines, B-0S12 antibody was positive with melanoma cells and negative with cells from bladder, cervix and mammary carcinoma. These cross reactions suggested, that the antibody is reactive with a protein, expressed on different tumor types. This protein is not expressed on the cell surface and is probably associated with cytoskeleton, as revealed by immunofluorescence experiments. Western-blot analysis of a cytoskeletal preparation of U-3930S cells suggests, that B-0S12 antibody recognizes a protein with Mr 55 kD. Further studies are needed to characterize the molecules, carrying the epitope, identified by this monoclonal antibody.
 ...
PMID:Monoclonal antibody to a human osteogenic sarcoma cell line. 304 55

The expression of a cell surface antigen defined by an anti-human osteogenic sarcoma monoclonal antibody was analysed by flow cytofluorometry using fluorescein-labelled antibody. Quantitative absorption tests established that the antigen was associated with plasma membranes, whereas cytosol, cellular lipids and nuclei were largely devoid of activity. Single-phase aqueous butanol solutions at non-cytolytic concentrations failed to solubilize the antigen, although treatment of cells with papain virtually abolished antigenic activity. The antigen was shown to be solubilized by the non-ionic detergent Nonidet P-40, and following lactoperoxidase-catalysed radioiodination of viable cells, extraction with detergent, immunoprecipitation of antigen with monoclonal antibody and Sepharose-Protein A, the molecular weight of antigen was determined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The findings indicate that this human osteogenic sarcoma antigen is a monomeric integral membrane protein with an apparent molecular weight of 72,000, which is predominantly expressed at the external face of the tumour cell plasma membrane.
 ...
PMID:Characteristics of a cell surface antigen defined by an anti-human osteogenic sarcoma monoclonal antibody. 634 92

Monoclonal antibody against an osteogenic-sarcoma cell line (791T) was prepared by production and cloning of a somatic-cell hybrid between the mouse myeloma P3-NS1 and spleen cells from 791T-immunized mice. Three clones of hybridoma producing antibody against 791T, as detected by 125I-labelled Protein A binding, were tested against a range of normal and tumour cell targets to determine the pattern of expression of the antigen detected. The 3 clones had identical activity. They reacted strongly against 791T cells and another osteogenic sarcoma, 788T, and more weakly against a further 2 from a total panel of 10 osteogenic-sarcoma lines. The antibody was negative for fibroblasts from the donor of 791T, and for other fibroblasts, human red blood cells, human peripheral mononuclear cells and sheep red blood cells. When tested against a panel of unrelated tumours, they reacted against individual cell lines derived from carcinomas of colon, lung, bladder and cervix. These cross-reactions were not observed with other colon or lung carcinomas, and it is suggested that the antibody was reacting with a tumour-associated antigen expressed randomly on different tumour types, rather than specifically on osteogenic sarcomas.
 ...
PMID:Antitumour reactions of monoclonal antibody against a human osteogenic-sarcoma cell line. 694 6

Monoclonal antibodies directed against one spontaneously arising rat mammary carcinoma and a human osteogenic sarcoma have been prepared following the fusion of spleen cells from appropriately immunised donors with mouse myeloma cells. The characteristics of these antibodies have been analysed and methods for their purification have been developed using immunoadsorption chromatography or by utilising their affinity for Sepharose-linked Protein A. The use of these antibodies for the identification, characterisation and isolation of their target tumour antigenic structures is described.
 ...
PMID:Characteristics of two anti-tumour monoclonal antibody preparations. 694 20

The genes regulated by p53, as well as the factors modulating its function, need to be identified before the mechanism of action of p53 in control of cell growth can be adequately understood. Binding of the SV40 large T-antigen protein to an evolutionally conserved (conformational) domain of p53 inhibits p53's DNA-binding and transcription activation activities. Cellular proteins might also bind to this same region of p53 to regulate its function. A hybrid protein composed of protein A fused to the conformational domain (amino acids 115-295) of p53 was expressed in Escherichia coli and used as an affinity probe for binding proteins in detergent lysates of non-small cell lung carcinoma (NSCLC) cells. The wild-type p53 hybrid protein associated with several major proteins of molecular weights 45 K, 56 K, and 70 K, as well as other minor species ranging in molecular weight from 30 K to 90 K. These proteins bound specifically to the p53 sequence of the hybrid protein. Protein A did not associate with these proteins and the two p53 hybrid proteins containing missense mutations at codons 273 and 175 exhibited a 40-80% weaker association. In addition, T antigen competed with the cellular proteins for binding to the conformational domain. The conditions of cell growth had a profound effect on the expression of the p53 binding proteins. Considerably more p53 binding proteins were expressed in actively growing cells than in cultures maintained under conditions for slow growth. Quantitative differences in expression of p53-binding proteins were observed among different NSCLC cell lines. The expression of p53-binding proteins was not restricted to NSCLC cell lines; detergent extracts of an osteosarcoma cell line yielded similar p53-binding proteins.
 ...
PMID:Binding of cellular proteins to a conformational domain of tumor suppressor protein p53. 824 46