Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Short- and long-term co-cultures of 49 cases of human osteosarcoma cells with bone marrow or peripheral blood cells of patients with different types of leukemia were studied. Morphological changes were observed in 7 of 13 long-term co-cultures resembling those induced by RNA tumor viruses. The changes were accompanied by appearance of cytoplasmic antigen as shown by fixed immunofluorescence test with sera from patients with osteosarcoma, leukemia, and of some apparently normal blood donors. Absorption with Forssman-like substances, whole human embryo cells or osteosarcoma cells demonstrated the reaction to be due to tumor antigen(s) in co-culture cells showing morphological changes. Electron microscopy showed a few type C virus particles in one co-culture. Cell-free filtrates of fluid from the transformed co-cultures induced morphological changes in 1 of 4 human embryo cultures. Uninoculated embryo cultures or those inoculated with filtrates from parental sarcoma or leukemia cultures showed no morphological changes. Human embryo cell cultures treated with fluid from parental leukemic bone marrow but not from parental sarcoma cultures showed appearance of cytoplasmic antigen by immunofluorescence test with sera of osteosarcoma and leukemia patients and of some apparently normal blood donors. Transformed human co-cultures showed the cytoplasmic antigen with 28 of 48 sera of osteosarcoma and leukemia patients tested, after absorption with Forssman-like material, human embryo, and mycoplasma suspensions. Fourteen of 49 sera of normal donors were also positive with the transformed co-cultures. Similar results were obtained in an earlier series of experiments with human embryonic cultures transformed by fluid from different osteosarcoma-leukemia co-cultures when examined by fixed immunofluorescence tests with sera of patients with osteosarcoma and leukemia. In 2 whole human embryo cell cultures showing morphological changes high molecular weight RNA was found, similar to that of RNA animal tumor viruses and in one of the cultures transient reverse transcriptase was detected.
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PMID:Virus retrieval studies in human neoplasia. 5 29

Sera from 8 of 9 patients with osteogenic sarcoma equally lysed autologous tissue-cultured cells of both skin and osteosarcoma in the presence of complement. Of 155 normal human sera tested, 103 (66%) lysed allogeneic normal ksin in tissue culture. These antibodies appeared more prevalent in younger (96% in ages 11-20 yr) than older (33% in ages 41-50 yr) humans. The presence of these "natural" antibodies against normal and malignant cells growing in tissue culture was possibly directed against components adsorbed to the cells during tissue culture or to "new" cell-surface antigens expressed by these cells grown in tissue culture. These non-tumor-related neoantigens on normal and malignant cells in tissue culture represented a potential source of confusion in studies of the serologic response of humans to tumors.
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PMID:Lysis of human normal and sarcoma cells in tissue culture by normal human serum: implications for experiments in human tumor immunology. 6 9

57Co-bleomycin appears to be one of the best tumor detecting agents at the moment. The localization within the cells is not yet known. This preclinical investigation had the aim to study the subcellular distribution of 57Co-bleomycin in liver, spleen and tumors of rats and mice. Mice with transplanted lymphosarcoma and osteosarcoma were used and rats with transplanted rhabdomyosarcoma. The concentration of 57Co-bleomycin was 2 to 10 times higher in the tumors as compared to the (normal) liver. This accumulation property was not found with the control substance: 57CoCl2. The highest radioactivity of 57Co-bleomycin (cpm/mg protein) was observed in subcellular fractions containing mitocohndria and lysosomes. After treatment of these fractions with hypertonic solutions it could be shown that enzymes of the mitochondrial matrix remained inside the vesicles under conditions of almost complete release of 57Co-bleomycin. Half of the lysosomal enzyme acid phosphatase was released too. From these experiments it is concluded that 57Co-bleomycin is preferentially localized in heavy secondary lysomes which are more fragile than the lighter lysosomes in the cells.
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PMID:Subcellular localization of 57Co-bleomycin in normal and tumor tissues. 7 96

Lung tumor-associated antigens of approximately 32,000 daltons were recognized by the use of sensitive radioimmunoassays and rabbit antisera, one raised against an extract of pooled human malignant lung tissues and another raised against a cell line derived from a human squamous cell carcinoma of the lung. These antigens differ from antigens described previously, including carcinoembryonic antigen and alpha-fetoprotein. The antigens were detected on 13 of 13 lung tumors (of all histologic types), fetal tissue, normal brain, 2 of 8 colon tumors, 2 of 9 prostate tumors, and 2 of 3 breast tumors, as well as on cell lines derived from lung tumors, neuroblastoma, human amnion, colon adenocarcinoma, and bladder tumors. They were not detectable on normal lung, liver, kidney, colon, or prostate tissues or on cell lines derived from osteosarcoma, fetal lung fibroblasts, transitional cell carcinoma, and squamous cell carcinoma of the skin. Lung tumors of different histologic types were concluded to express common, tumor-associated oncofetal antigens that are found less often on tumors of other organs.
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PMID:Human lung tumor-associated antigens of 32,000 daltons molecular weight. 9 95

A RNA-dependent DNA polymerase (RTase) was purified from human osteosarcoma tissue by successive column chromatography of the microsomal fraction on DEAE-cellulose (DE-23 and DE-52) and phosphocellulose. The purified enzyme has a molecular weight of about 68,000, a pH optimum of 8.1, a Mg2+ optimum of 0.8 mM, Mn2+ optimum of 1.0 mM and a KCl optimum of 60 mM. The enzyme transcribes (rA)n . (dT)12, (rC)n . (dG)12-18 and (2-O-methyl C)n . (dG)18, but is unable to transcribe (dA)n . (dT)10. The enzyme has no catalytic activity in the presence of oligodeoxynucleotide initiators alone, indicating the absence of terminal deoxynucleotidyl transferase. The purified enzyme is able to transcribe the heteropolymeric regions of a 70S RNA from R(Mu)LV. The presented data support the presence of a RNA-dependent DNA polymerase in human osteosarcoma tissue with biochemical properties, resembling those of C-type RNA tumor viruses.
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PMID:Purification and biochemical characterization of a virus-specific reverse transcriptase from human osteosarcoma tissue. 9 60

Tw osteosarcomas of jaw bones have been studied by electron microscopy. The objectives were to examine the specific cell types in relation to functions and ultrastructural features, and to examine matrices produced by tumor cells. The osteosarcoma cells were subdivided into four cell types: anaplastic, chondroblastic, osteoblastic, and osteocytic--giant cells were not considered in the present investigation. Compared to normal bone cells, no specific sign of malignancy was found. However, tumor cells seem to lose functional abilities, i.e. a modification of matrix. Consequently, tumor matrix has altered organic and inorganic components with impairment of collagen maturation and matrix mineralization. The alteration in both processes may be related to a diminished production of proteoglycans. The cytogenic hypothesis of a tumor stem cell may be supported by the identification of anaplastic osteosarcoma cells resembling immature reticulum cells. One may speculate on transformation of this cell type as a genetically predetermined osteoprogenitor cell of malignant potential.
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PMID:Ultrastructural study of tumor cell differentiation in osteosarcoma of jaw bones. 9 36

A single intramedullary administration of each dose (15 approximately 20 mg) of 4-nitroquinoline 1-oxide, 3-methylcholanthrene, or 7,12-dimethylbenz[alpha]anthracene was applied to the mandible, diaphysis, or distal metaphysis of the femur of rabbits. The highest incidence in production of osteosarcoma was obtained from the group in which 4-nitroquinoline 1-oxide was applied to the distal metaphysis (75%, including one case of chondrosarcoma). Tumors hardly appeared in any of the groups when given 3-methylcholanthrene or 7,12-dimethylbenz[alpha]anthracene. Histologically, three kinds of entities were recognized from the quantitative difference of the reactive tissues which appeared around carcinogens. It is estimated that the condition of entity III induces the highest incidence of osteosarcoma if chemical carcinogens are given into the bone marrow of experimental animals.
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PMID:Difference in the induction of osteosarcoma in rabbit bone with single administration of three kinds of chemical carcinogens. 10 16

Experience with computed tomography (CT) in 25 patients with histologically proven osteosarcoma is presented. CT was as accurate as conventional radiographic methods in determining the presence of a lesion, but it was definitely superior in defining the extent of disease, particularly intramedullary extension and soft tissue extraosseous tumor component. CT was capable of demonstrating skip metastases in one patient. CT plays a key role in the preoperative evaluation of osteosarcoma patients, particularly when less than radical surgery is planned as primary treatment and when postoperative recurrence is suspected. CT is also useful in assessing the response to therapy in nonsurgical cases. The technique involved in the performance of this examination is discussed.
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PMID:Computed tomography in the evaluation of osteosarcoma: experience with 25 cases. 10 81

For many years, research into human cancer has concentrated on human patients and on artificially induced neoplasms in inbred murine hosts. Cancer, however, affects a great variety of mammals, particularly those that have been domesticated. Suchf naturally occurring neoplasms are common in dogs, cats, cattle, horses, etc., and offer fertile ground for studies relating to epidemiologyf, etiology, immunobiology, and therapy. Canine osteosarcoma is described in detail. The clinicopathologic features of this canine tumor closely approximate that of human osteosarcoma and thus make canine osteosarcoma an invaluable comparative model. Canine osteosarcoma and other naturally occurring tumors lie intermediate between the mouse models and human cancer. The use of these veterinary models in the future fabric of cancer research will broaden its base and will influence our conceptual approach to research and clinical options.
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PMID:The use of naturally occurring cancer in domestic animals for research into human cancer: general considerations and a review of canine skeletal osteosarcoma. 11 62

Sixty-one patients with osteosarcoma were treated. Twenty-four of these patients were managed with our systematic multi-modal treatment. Overall survival rate was markedly improved chiefly by intensive systemic chemotherapy with multiple drugs, especially adriamycin and high dose methotrexate. Preoperative regional intra-arterial infusion of anti-tumor drugs and fast neutron radiotherapy were employed and it was suggested that fast neutron had a higher relative biological effectiveness and a greater therapeutic gain factor as compared with X-rays. Fast neutron radiotherapy can play a significant role in the very systematic treatment of osteosarcoma and is specifically useful for preservation of the affected limbs.
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PMID:Systematic multi-modal treatment of osteosarcoma, with special reference to the role of fast neutron radiotherapy. 11 50


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