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)

Sections were taken from the center, midzone, and margin of four human osteogenic sarcomas and one fibrosarcoma. Single-cell suspensions of tumors were examined in an indirect immunofluorescence assay with autologous or homologous anti-osteogenic sarcoma antisera as the intermediate reactant and fluorescein-labeled anti-human IgG as the final reactant. Cells were stained under conditions in which the fluorescence intensity was directly proportional to the density of the tumor-associated antigen on these cells. The density of tumor-associated antigen on cells from the center of the five tumor masses was low; cells from the midzone had intermediate levels of tumor antigen density, and cells at the margin had the highest levels. Similar preparations stained with polyspecific anti-HLA antisera did not demonstrate such a gradient. Since osteogenic sarcomas grow outward from the center, with the outer margin populated by the youngest cells, these results suggest that the oldest cells in the tumor bear the least tumor antigen, and the youngest tumor cells have the most. This is not compatible with theories which postulate that the immune system modulates the growth of a tumor so that only the least antigenic cells are allowed to grow. Alternative mechanisms are discussed.
 ...
PMID:Antigenic differences among osteogenic sarcoma tumor cells taken from different locations in human tumors. 6 91

The administration of an aqueous-ether extracted residue of Brucella abortus (Bru-Pel) inhibits development of transplanted osteogenic sarcomas in mice as evidenced by a decrease in mortality. At least one mechanism through which Bru-Pel modulates host resistance is activation of macrophages of the reticuloendothelial system. Peritoneal macrophages harvested from mice receiving Bru-Pel were cytotoxic for osteogenic sarcoma cells in vitro, limited the replication of vaccinia virus in cell cultures, and demonstrated enhanced emittance of chemiluminescence during phagocytosis of zymosan particles of Candida albicans. The concept of reticuloendothelial system activation was further supported by the evidence that administration of Bru-Pel enhanced resistance of mice to challenge with a lethal inoculum of Listeria monocytogenes. These observation support the hypothesis that Bru-Pel shares a number of characteristics with recognized immunomodulating agents and that one mechanism by which it modulates host resistance to tumors, to virus infections, and to challenge with L. monocytogenes is through activation of macrophages.
 ...
PMID:Enhancement of resistance to murine osteogenic sarcoma in vivo by an extract of Brucella abortus (Bru-Pel): association with activation of reticuloendothelial system macrophages. 10 4

Several benign and malignant tumors of bone and cartilage were examined by means of type-specific collagen antibodies in connection with indirect immunofluorescence technique in order to determine wether there is a positive correlation between cell morphology and gene expression as refered to the synthesis of tissue- or cell-specific collagen. In general benign bone and cartilage tumors show the collagen type corresponding to the original maternal tissue. In malignant osteogenic tumors a strong positive correlation was found between morphologic differentiation of osteosarcoma cells and tissue specific collagen synthesarcomas. Unrelated to the grade of differentiation and the type of malignant tumor, collagen type III could be demonstrated in all tumors investigated, occurring rather from vascular stroma than from the tumor cell itself.
 ...
PMID:Immunhistochemical demonstration of different collagen types in the normal epiphyseal plate and in benign and malignant tumors of bone and cartilage. 14 52

Benign osteoblastoma is a rare tumor, more frequent in males, usually occurring in patients under the age of 30 years, and is seen most frequently in the spine, femur, tibia, and mandible. Its varied roentgenographic appearance may suggest a large osteoid osteoma or an aneurysmal bone cyst, but about one-fourth of cases present a picture consistent with a malignant neoplasm. The roentgen changes in the spine are frequently subtle and require care for identification. Differentiation from osteogenic sarcoma is sometimes difficult even with histological material, because some low grade osteogenic sarcomas contain areas resembling osteoblastoma. Conservative surgery is the treatment of choice for osteoblastoma.
 ...
PMID:The spectrum of osteoblastoma. 17 1

The transformed cells that arise from among the hamster epithelial and mesenchymal cells exposed to SV40 in vitro are, as a rule, fibroblastoid and pleomorphic rather than epithelioid. Moreover, the neoplasms that these transformed cells induce in the allogeneic host are spindle cell sarcomas and pleomorphic sarcomas rather than carcinomas. Since this phenomenon may result from cellular dedifferentiation in culture, to the extent that the anaplastic morphology and lack of specialized function can no longer suggest the cell or origin, we investigated the fate of the differentiated state of cells of three types of SV40-induced hamster tumors before and after serial passage in vitro. The tumors evaluated were three reticulum cell sarcomas, three osteogenic sarcomas, and two lymphosarcomas of B-cell origin. Our data demonstrate that reticulum cell sarcoma cells lose their morphological differentiation soon after the original tumors are dissociated into cell suspensions but preserve their phagocytic activity throughout their in vitro passage. Osteogenic sarcoma cells lose their differentiated phenotype and their capacity to form osteoid during but not before their serial passage in culture. Lymphosarcoma cells preserve their lymphoid morphology and their ability to produce immunoglobulin even after many in vitro passages. These results indicate that, in many types of SV40-induced tumors, neoplastic cell dedifferentiation, following serial passage in culture, is responsible to a great extent for the emergence of new cell phenotypes lacking in morphological and functional features characteristic of the cells originally transformed by SV40.
 ...
PMID:Loss or persistence of the differentiated state of simian virus 40-induced hamster tumor cells before and after serial passage in culture. 18 42

Bone cancer can be induced by radionuclides that localize in the skeleton. Histologically, these experimentally induced tumors resemble those found naturally in man; they range from densely ossified osteogenic sarcomas to osteolytic tumors with giant cells and only a small osteoid component. Fibrosarcomas and hemangiosarcomas also can occur in some species. It has not been possible to determine the dose in terms of absorbed energy necessary for bone-tumor induction because radionuclides are not deposited uniformly, and they diminish in amount with time. Also, the precise time when irreversible noeplastic change occurs is not known. With X-rays, however, 500 rads delivered to the endosteal surface of a mouse femur has been shown to cause osteogenic sarcoma. Bone tumors can be induced in mice by viruses. FBJ osteosarcoma virus and RFB osteoma virus were obtained from spontaneous tumors; FBR osteosarcoma virus came from a radiation-induced tumor. All three are RNA viruses with C-type particle morphology, and they are propagated by injecting cell-free extracts of virus-induced tumor. All three are RNA viruses with C-type particle morphology, and they are propagated by injecting cell-free extracts of virus-induced tumor into newborn mice. Interaction studies with bone-seeking radionuclides and these viruses have led to the hypothesis that radiation produces cancer by inactivating a viral inhibitor. There is also evidence of a bone tumor virus in the human disease. The injection of cell-free extracts of human bone cancer into newborn Syrian hamsters has induced a variety of mesenchymal tumors at a rate significantly higher than in the control hamsters. Sixty tumors of this type, including 20 osteosarcomas, 11 fibrosarcomas, and 9 osteomas, have been diagnosed so far in experimental animals; in control hamsters there has been only one, a fibrosarcoma. Immunofluorescence assays and cytotoxicity studies indicated that these hamster tumors carried a human antigen.
 ...
PMID:Pathogenesis of radiation and virus-induced bone tumors. 18 72

This study was undertaken to find out if there are any factors of prognostic significance that can help the surgeon in the management of osteogenic sarcoma. One hundred and thirty-nine cases of osteogenic sacrocma were treated during a 30-year period and their survival figures have been analysed with respect to age, sex, extent of disease, previous treatment, and value of lymphadenectomy. We found that patients in whom the lymph nodes were preserved had a better survival as compared to patients in whom the lymph nodes were removed en bloc with the primary tumour. This further supports our contention that the regional lymph nodes have an important role to play in the immune response against osteosarcoma. The experimental work of the cytotoxic action of regional lymph node cells against osteosarcoma cell lines has been studied in our laboratory. The results of this study stimulated us to undertake this retrospective analysis.
 ...
PMID:Prognostic significance of the regional lymph nodes in osteosarcoma. 26 34

Doubling time values of pulmonary metastases from soft tissue sarcomas were measured. Sixty metastases from 24 patients were measured 79 consecutive times, and, the values for 116 doubling times were calculated. Small volume metastases grew significantly faster (arithmetic mean 29.7 days) than large metastases (arithmetic mean 43.4 days). An assessment with comparative data obtained previously by measuring the doubling time values of pulmonary metastases from osteogenic sarcoma revealed similar growth characteristics. The possible involvment of identical control mechanisms operating in the growth process of pulmonary metastases in both soft tissues and osteogenic sarcomas are discussed.
 ...
PMID:Actual volume doubling time values for pulmonary metastases from soft tissue sarcomas. 27 19

Great progress has been made both in the treatment of metastatic sarcomas and in adjuvant treatment of Ewing's, rhabdomyo- and osteogenic sarcomas. This is due partly to new and more effective cytostatic drugs and combinations, but to a greater extent to an improved systematic multimodal approach. In patients with metastatic sarcoma, better and longer remissions can be achieved, whereas real cures are possible in Ewing's, rhabdomyo- and osteosarcoma if properly managed using an interdisciplinary approach. Patients with these rare malignancies should be referred to specialized cancer centers, in view of the problems and possible complications of their necessarily intensive therapy.
 ...
PMID:[Bone and soft tissue sarcomas]. 27 26

A comparative electrone microscopic investigation of osteogenic sarcomas and giant-cell bone tumors has revealed the ultrastructural differences between a mononuclear component of the giant-cell tumor and the most frequently observed type of osteogenic sarcoma cells (a well-developed ergastoplasma in cells of osteogenic sarcoma and moderately developed one- in the giant-cell tumor of bones, different rate of development of the mitochondrial apparatus, the character of nuclei) that indicates different genesis of these two tumor types. In giant-cell bone tumors a definite ultrastructural similarily between some mono- and multinuclear cells (a large number of mitochondrial, similar character of nuclei) may speak in favour of the common source of their development and explains the high activity of oxidoreduction enzymes in them revealed histochemically.
 ...
PMID:[Ultrastructure of a giant cell tumor of the bones and of osteogenic sarcoma]. 28 63


1 2 3 4 5 6 7 8 9 10 Next >>