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Query: UMLS:C0029463 (osteosarcoma)
 16,637 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two cases of osteosarcoma are described arising in patients who had undergone angiography with Thorotrast during childhood. In both patients, there was radiographic and pathologic evidence of radioactive thorium dioxide deposition in bone as well as throughout the reticuloendothelial system. Thorotrast deposits were demonstrated in the immediate vicinity of the primary tumors by both histology and autoradiography. Previous cases of osteosarcoma associated with Thorotrast administration from the literature are cited, and possible causal relationships are discussed between thorium retention in bone and neoplastic transformation by chronic radiation.
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PMID:Osteosarcoma associated with Thorotrast administration: report of two cases and literature review. 36 15

Tumours of mixed glial and sarcomatous elements occurring in intracranial neoplasms are well recognised and have been termed gliosarcomas. These tumours account for up to 8% of all glioblastomas. The sarcomatous elements are thought to derive from the neoplastic transformation of mesenchymal cells in or adjacent to the tumour. This transformation usually has the appearance of a fibrosarcoma or angiosarcoma. Alternative mesenchymal neoplastic differentiation may occur, however, giving rise to the appearances of chondrosarcoma and osteosarcoma. In 1969 Goldman described a case in which the sarcomatous elements of a mixed gliosarcoma appeared, on the basis of light microscopy alone, to differentiate towards skeletal muscle having the features of a rhabdomyosarcoma. He coined the term gliomyosarcoma. In 1986 Barnard et al reported a second case and demonstrated the features of rhabdomyosarcoma using the electron microscope. A further case characterised with both light microscopic and immunohistochemical techniques is reported.
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PMID:Gliomyosarcoma: an immunohistochemical analysis. 152 49

We have used both biochemical and morphological techniques to characterize PTH receptors on the clonal osteosarcoma cell line UMR-106, a widely used model of the osteoblast phenotype. 125I-labeled rat (r) PTH-(1-34) bound to a single class of specific saturable receptors on both whole cells and membranes prepared from UMR-106 cells in a time- and temperature-dependent manner. A decrease in PTH receptor affinity seen in the presence of guanine nucleotides demonstrated that PTH receptors on the UMR-106 cells are coupled to guanyl nucleotide-binding proteins. Although PTH is a potent stimulator of adenylate cyclase in the UMR-106 cells, comparison of PTH-stimulated adenylate cyclase and PTH binding curves indicated the presence of receptors that are not linked to the adenylate cyclase system. Our studies also demonstrated that 125I-labeled rPTH-(1-34) bound to UMR-106 cells is rapidly internalized at 22 C, whereas PTH bound at 4 C remains intact and on the cell surface. Internalization of 125I-labeled rPTH-(1-34) was associated with degradation and release of the hormone at 22 C. Three morphologically distinct cell types were identified in subconfluent cultures of UMR-106 cells. Autoradiographic analysis of 125I-labeled rPTH-(1-34) binding demonstrated differential PTH receptor expression in these cell types. The most abundant PTH binding was observed over a cell type with long cytoplasmic extensions. This cell was reminiscent of the predominant PTH target cell previously identified in the rat metaphysis in vivo, suggesting that the UMR-106 cell line may represent neoplastic transformation of the PTH target cell.
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PMID:Biochemical and morphological characterization of parathyroid hormone receptor binding to the rat osteosarcoma cell line UMR-106. 215 23

Established osteoblast-like (OB) cells infected with the bone tumor-inducing C-type retrovirus OA MuLV remained nontumorigenic over 104 cell culture passages. DNA histograms revealed a new cell population with a stem line peak at 5c. A second OA MuLV-infected OB cell line underwent neoplastic transformation with increasing passage level. These cells showed diffuse aneuploidy. Stepwise linear discriminant analysis of the chromatin structure of control, OA MuLV-infected, and FBR osteosarcoma virus-transformed cell lines resulted in various levels of discrimination ranging between 79.6% for control cells versus nontumorigenic OA MuLV-infected cells, and 96.6% for nontumorigenic OA MuLV-infected cells versus FBR osteosarcoma virus-transformed cells. OA MuLV-infected tumorigenic cells and FBR osteosarcoma virus-transformed cells were discriminated at a 93.6% level.
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PMID:Computer-assisted imaging cytometry of nuclear chromatin reveals bone tumor virus infection and neoplastic transformation of adherent osteoblast-like cells. 255 99

Previously we have reported the development of a model in vitro system for the study of osteosarcoma. In this system, when chick periosteal explants are infected with Fujinami sarcoma virus (FSV), osteosarcoma-like tissue is formed. In the present study, a series of histopathologic parameters of neoplastic transformation and osteogenesis were quantitated, at a single cell level, by computer-assisted morphometry. Most significantly, it was found that compared to uninfected (control) cultures, in the FSV-infected (experimental) cultures, the bone to osteoid ratio per unit area was decreased due to a relative decrease in the area of bone and an increase in the area of osteoid. The cellularity of the FSV-infected tissues was significantly increased due to an increase in the number of unlabeled and [3H]thymidine-labeled cells, while the proportion of alkaline phosphatase (AP) positive cells decreased. Double-label immunohistochemistry (with anti-P140gag-fps) and histochemistry for AP activity was performed, to demonstrate production of the oncogene-encoded protein, and osteoblastic differentiation respectively. In an in vitro transformation assay, single cells derived from control, uninfected cultures did not grow, while those derived from FSV-infected cultures formed colonies in semisolid medium. Some of these colonies demonstrated AP staining. Taken together these data show that in this in vitro system (i) neoplastic transformation of osteogenic cells does occur, (ii) changes in osteoid and bone production are related to neoplastic transformation, and (iii) osteosarcoma-like changes can be quantitated at the individual cell level.
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PMID:Neoplastic transformation of osteogenic cells: quantitative morphometric analysis of an in vitro model for osteosarcoma. 284 30

Recently we have developed a model in vitro system for the study of factors regulating the histogenesis of osteosarcoma. In this system, Fujinami sarcoma virus (FSV) induces osteosarcomatous changes such as increased cell proliferation and altered patterns of bone and nonmineralized matrix (osteoid) formation. Such changes can be quantitated at the individual cell level, by computer-assisted morphometry. Here we report on the effects of dexamethasone (DEX) on FSV-induced neoplastic transformation and osteogenesis in chick embryonic periosteum cultures, as reflected by a series of histopathological parameters. Most significantly, it was found that compared to 10(-9) M DEX treated cultures, in 10(-7) M DEX pretreated cultures, the bone/osteoid ratio was increased due to a relative increase in the area of bone and a decrease in the area of osteoid. The number of [3H]thymidine-labeled cells decreased significantly, while the proportion of alkaline phosphatase positive cells increased. Double-label immunohistochemistry (with anti-P140gag-fps) and histochemistry for alkaline phosphatase activity was performed, to demonstrate production of the oncogene-encoded protein, and osteoblastic differentiation, respectively. In an in vitro transformation assay single cells derived from 10(-9) M DEX treated cultures formed a significantly higher number of colonies than those obtained from 10(-7) M DEX pretreated cultures. Taken together, the data indicate that in the chick embryonic periosteum culture system, pretreatment with 10(-7) M DEX inhibits the ability of FSV to induce neoplastic transformation. This effect is probably the result of DEX-induced cell differentiation, prior to infection with FSV.
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PMID:Dexamethasone effects on induction of neoplastic transformation by Fujinami sarcoma virus in an in vitro chick embryo periosteal model for osteosarcoma. 284 66

Our present knowledge about bone tumors is still in need of a convincing cytohistogenetic concept that would support the adequate differentiation and classification of different tumor types. The modern therapeutic approach must rely on subtle diagnostis using preferably cyto- and histomorphologic criteria. The present study depends on a considerable number of malignant and semimalignant bone tumors which were analysed by several modern investigative methods. Based on these results, we intend to find the answers to some problems of cytogenesis and histogenesis of bone tumors. Comparison and correlation of our findings with the results of other authors is attempted with the objective to propose an overall histogenetic concept of bone tumors in consideration of the known data and hypotheses. Our material comprises 85 malignant and semimalignant bone tumors. The following tumor types are discussed on the basis of cases from our collection (numbers in brackets): "Conventional" highly malignant osteosarcoma (32), parosteal and periosteal osteosarcoma (2), telangiectatic osteosarcoma (2), small cell osteosarcoma (1), small cell sclerosing osteosarcoma (2), histiocytic osteosarcoma (1), Ewing's sarcoma (15), "conventional" chondrosarcoma (7), dedifferentiated chondrosarcoma (2), mesenchymal chondrosarcoma (1), giant cell tumor (12), malignant fibrous histiocytoma of bone (5), fibrosarcoma of bone (3), The results of conventional light and electron microscopy, but also of enzyme histochemistry and autoradiography were included in the definitive classification by both histologic and cytologic criteria. In addition, different collagen types present in the ground substance of these tumors were studied by immunofluorescence microscopy; in anaplastic tumors of high malignancy the intermediate filaments of the cytoskeleton were further subjected to immunohistochemical analysis. The concept resulting from these studies may be briefly summarized as follows: The stem cell of conventional, highly malignant osteosarcoma is a stromal cell of the skeletal system, which is undergoing neoplastic transformation. At first this cell fails to show any sign of collagen synthesis, the activity of alkaline phosphatase is not increased. Of a primarily anaplastic nature, this tumor cell may differentiate in several directions: in osteoblastic differentiation, the cell will produce predominantly collagen type I, and alkaline phosphatase activity will increase. During fibroblastic differentiation we observe an increased synthesis of collagen type III, but alkaline phosphatase activity is not raised.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[Cytogenesis and histogenesis of malignant and semimalignant bone tumors]. 609 60

Cellular genes containing nucleotide sequences homologous to retroviral oncogenes (v-onc) have been identified in the genomes of a variety of species of both the vertebrate and invertebrate phyla. Expression of such genes, termed c-onc genes, has been shown to be tissue-specific in chickens and mice and to be modulated during murine development and differentiation of human haematopoietic cells. We report here that the level of the c-fos gene transcripts is 100-fold greater in human term fetal membranes than in other normal human tissues and cells. These levels of c-fos expression in human amniotic and chorionic cells are close to the level of v-fos expression that results in the induction of osteosarcomas in mice and transformation of fibroblasts in vitro. This observation suggests that the induction of neoplastic transformation by the FBJ murine osteosarcoma virus may require the expression of the fos gene product at high levels in an inappropriate cell type. In contrast, the human c-fms gene is expressed at high levels specifically in term placenta and trophoblastic cells. The tissue and cell type-specific patterns of c-fos and c-fms expression suggest that the physiological function of the c-fos and c-fms encoded proteins may be associated with those embryo-derived cells whose primary functions are protection and nourishment of the human fetus.
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PMID:Tissue and cell type-specific expression of two human c-onc genes. 687 68

Hormone-related cancers account for almost 30% of all cancer cases in the United States. Data from animal experiments and from epidemiological and endocrinological studies in humans support the hypothesis that the individual hormones which control normal growth of target organs can also create the proper conditions for neoplastic transformation. The concept that hormones can cause, i.e., increase the incidence of, human cancer is most developed for the four hormone-related cancers which are numerically the most important, namely, breast, prostate, endometrium, and ovary. Even for these sites, large gaps remain in our knowledge of the responsible hormones and the conditions which create the optimal opportunity for carcinogenesis. Although scanty, the available epidemiological evidence also suggests a hormonal role in the pathogenesis of testis cancer, thyroid cancer, and osteosarcoma. We believe that the primary prevention of all these cancers will probably depend on modification of the factors which affect the secretion and metabolism of the responsible hormones rather than on control of exposure to classical exogenous initiators.
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PMID:Endogenous hormones as a major factor in human cancer. 704 21

Twelve human cell cultures derived from tumors, normal tissues, and derivative cultures transformed by either a RNA tumor virus or chemical carcinogen were examined for their response to cytochalasin B (CB) and the expression of this marker was correlated with growth in soft agar and saturation density in monolayer culture. Cell lines derived from carcinoma of the bladder (T24 and RT4), kidney (Caki-1), prostate (DU 145), and breast (MCF-7) multinucleated when growth in CB-supplemented medium, whereas cell cultures derived from benign bladder epithelium (HCV-29), and normal kidney (Flow 4000) and skin (GM10) remained binucleate under comparable conditions. Human osteosarcoma (HOS) cells transformed by murine sarcoma virus (MSV) or a chemical carcinogen extensively multinucleated in response to CB treatment, relative to a morphological revertant of MSV-transformed HOS and parental HOS cells. CB-induced multinucleation was consistently correlated with the ability of cells to form colonies in soft agar but inconsistently correlated with growth to high saturation densities. These results demonstrate a differential response to CB by normal and transformed human cells and that CB-induced multinucleation provides a convenient and useful in vitro marker for neoplastic transformation.
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PMID:Cytochalasin B-induced multinucleation of human tumor and normal cell cultures. 739 90


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