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 effect of recombinant Pasteurella multocida toxin (PMT) on primary cultures of embryonic chick bone-derived osteoblastic cells was investigated. It was found that PMT was a potent mitogen for primary derived chicken osteoblasts. The toxin stimulated DNA synthesis and cell proliferation in quiescent osteoblasts at the first passage and accelerated cell growth in subconfluent cultures. Cell viability was not affected by PMT, even at relatively high concentrations. Osteoblast numbers increased in a dose-dependent manner in response to PMT. Intracellular inositol phosphates were elevated in response to PMT, but no elevation in cyclic AMP (cAMP) levels was evident. Indeed, PMT inhibited cAMP elevation in osteoblasts in response to cholera toxin at a stage before other PMT-mediated events take place. In addition to increased cell turnover, PMT down-regulated the expression of several markers of osteoblast differentiation. Both alkaline phosphatase and type I collagen were reduced, but osteonectin was not affected. The in vitro deposition of mineral in cultures of primary osteoblasts and osteoblast-like osteosarcoma cells was also inhibited by the presence of PMT. This suggests that PMT interferes with differentiation at a preosteoblastic stage.
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PMID:Pasteurella multocida toxin is a mitogen for bone cells in primary culture. 864 7

Thirty-three osteosarcomas at various grades of histologic differentiation, including chondroblastic, osteoblastic, and fibroblastic variants, were investigated immunohistochemically for evidence of osteonectin. Twenty-two cases of varying types of osteosarcoma were examined with in situ hybridization for mRNA expression of osteonectin. Immunohistochemically, osteonectin was present in all the osteosarcomas in this study. With in situ hybridization, 12 out of 22 osteosarcomas showed a positive signal. Two osteochondrosarcomas, seven chondrosarcomas, and one mesenchymal chondrosarcoma were also studied with regard to the localization of osteonectin, either immunohistochemically or by in situ hybridization. Immunohistochemically, osteonectin was present in all the chondroid lesions except for one osteochondroma. However, in situ hybridization of osteonectin mRNA was negative in all the chondroid lesions we studied. This study revealed that immunohistochemical localization of osteonectin is not useful in providing conclusive diagnosis of osteosarcoma. In situ hybridization of osteonectin mRNA might be useful in differentiating osteosarcoma from nonsteogenic bone tumors.
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PMID:The impact of osteonectin for differential diagnosis of osteogenic bone tumors: an immunohistochemical and in situ hybridization approach. 871 13

To distinguish the origin of bone-forming cells in the osteosarcoma (OST) tumor inoculated into nude mice, we have developed a novel in situ hybridization technique. The system used digoxygenin (DIG) labeled DNA probes that encoded human specific repetitive gene, Alu, and mouse specific repetitive gene, mouse L1 (m-L1). The chondrogenic and osteogenic cells in the tumor had strongly positive signals for m-L1 probe without any signals for Alu probe. The expression of bone matrix proteins was also examined by in situ hybridization. The bone-forming cells were positive for mRNAs of mouse osteonectin, osteopontin, and osteocalcin relating to calcification during bone formation, while these were negative for human mRNAs of these bone matrix proteins. The OST cells in the tumor expressed the human bone morphogenetic proteins (BMPs) mRNAs by RT-PCR. These data indicated that the mouse cells, not the human sarcoma cells, are responsible for cartilage and bone formation in the OST tumor inoculated into nude mice, and we speculated that BMPs, at least in part, could play an important role in this ossification.
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PMID:Human osteosarcoma (OST) induces mouse reactive bone formation in xenograft system. 892 42

Two human osteosarcoma cell lines, Hu09 and OST, were suspended in Matrigel (Becton Dickinson Labware, Bedford, Massachusetts) and implanted subcutaneously in the backs of nude mice. To study phenotypic changes of tumor cells and host cells, expression of mRNA for osteopontin (OPN), osteocalcin (OC), and osteonectin (ON) was analyzed by in situ hybridization. Bone tissue was formed in the tumors derived from Hu09 cells. OPN mRNA was transcribed predominantly in osteocyte-like cells within the bone, whereas OC mRNA was transcribed in osteoblast-like cells that surrounded the bone. ON mRNA was detected in both types of cells. The similarity of the expression pattern of OPN, OC, and ON during osteogenesis of Hu09 cells to that of normal skeletal development suggests that the bone formed in Hu09-implanted mice is the same as normal bone tissue. By DNA-DNA in situ hybridization using a human-specific Alu probe and a mouse-specific m-L1 probe, osteoblast-like cells in Hu09 tumorous bone were, however, of human origin, whereas osteocyte-like cells were of mouse origin. In the tumors derived from OST cells, no osteogenesis was observed during the experimental period, and the expression of OPN, OC, and ON was not detected in tumor cells. An endochondral bone formation was not evident when these cells were simply implanted into muscle tissue. An endochondral bone was, however, reactively induced in the host mUscle tissue either when 1 alpha-hydroxyvitamin D3 and all-transretinoic acid were administered to OST-implanted mice or when Hu09 cells were pretreated with dexamethasone before implantation. Hu09 implantation seems to be a useful tool not only for the study of the differentiation of osteosarcoma cells but also for the investigation of the mechanism of bone formation. This system, using Hu09 and OST, may provide us with a new tool for the isolation of the unidentified factors that induce or inhibit osteogenesis in vivo.
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PMID:In vivo implantation of human osteosarcoma cells in nude mice induces bones with human-derived osteoblasts and mouse-derived osteocytes. 894 Dec 16

A case of intraosseous well-differentiated osteosarcoma in one phalanx of the hand is reported. A 78-year-old man noticed swelling in the little finger of his right hand approximately 7 years before referral. Imaging disclosed a tumour with a "ground glass" appearance and irregular mottled calcification occupying almost all of the phalanx marrow and suggested slight invasion into the soft tissue. Open biopsy suggested a diagnosis of well-differentiated fibroblastic osteosarcoma. The finger and its metacarpal bone were amputated and a tumour measuring 3.5 x 2.2 x 2.0 cm and with an indistinct soft tissue margin was found in the bone marrow. Histologically, the tumour was composed of fibroblastic cells with few mitoses, and neoplastic bone formation was apparent. Although the tumour appeared to be a fibrous dysplasia, the presence of nuclear atypia, hypercellularity, and the absence of a typical woven bone pattern in addition to the soft tissue invasion indicated otherwise. Ultrastructural examination showed focal myofibroblastic differentiation, and immunohistochemistry revealed smooth muscle actin, vimentin, osteocalcin, osteonectin and MIBI in the tumour cells. This ultrastructural and immunohistochemical study is believed to be the first detailed report of an intraosseous well-differentiated osteosarcoma of phalangeal bone.
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PMID:Phalangeal intraosseous well-differentiated osteosarcoma of the hand. 908 23

Until now, many extracellular matrix proteins, e.g. osteopontin and osteonectin, have been used to determine a cell's osteogenic maturation. The disadvantage in evaluation of these proteins is their relative wide-ranging appearance throughout the osteogenic differentiation process. Thus, the aim of this study was to establish an immunohistochemical setup using E11, a marker that binds selectively to cells of the late osteogenic cell lineage. In addition, the histochemical expression of the bone matrix proteins osteonectin, osteopontin and fibronectin was compared to that of E11 using monoclonal antibodies. For light microscopical detection of osteogenic markers in cultured cells we developed a simple paraffin technique using a fibrin glue as embedding medium. This allows the handling of cultured cells such as a tissue sample and includes the use of stored biological specimens for further immunohistochemical experiments. We used newborn rat calvariae for whole tissue preparations and for isolation and cultivation of bone cells. In addition, we included the rat osteosarcoma cell line ROS 17/2.8 in this study. For the first time, we have localised E11 in osteocytes of rat calvaria preparations at the electron microscopical level. E11 was detected at plasma membranes of osteocytes and their processes, but not at those of osteoblasts. Accompanying experiments with cultured newborn rat calvaria cells and ROS 17/2.8 cells revealed E11 reactivity on a subset of cells. The results obtained confirm the suitability of the differentiation marker E11 as a sensitive instrument for the characterisation of bone cell culture systems.
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PMID:Immunohistochemical investigations on the differentiation marker protein E11 in rat calvaria, calvaria cell culture and the osteoblastic cell line ROS 17/2.8. 993 Aug 85

Osteosarcomas produce an extracellular matrix (ECM), called tumor osteoid, which is also the microscopic hallmark of these tumors. It can be difficult to differentiate tumor osteoid from other formations of ECM in intra-and extraskeletal soft tissue tumors, so that problems in differential diagnosis arise. Conventional special stainings provide a means to increase the reliability of the differential diagnosis, but do not identify the type of tumor conclusively as they only reflect physiochemical features and do not identify the molecular components of the matrix. The key to the solution of this problem is the immunohistochemical use of antibodies against bone matrix components. Matrix-immunohistochemistry using polyclonal and monoclonal antibodies against COL-I-C-peptide, Osteopontin, Osteonectin, Osteocalcin, and Decorin have proved to be a useful tool for the differentiation of osteoid in a series of 20 osteosarcomas with different variants of osteoid formation. For the detection of undifferentiated tumors, however, this method has not proved useful, since the cytoplasmatic immunoreactivity is variable. Molecular methods appear to be a more promising tool. Since the expression of Osteocalcin is known to be the last step of the osteoblastic differentiation, we have established a method to detect osteocalcin mRNA by RT-PCR. First studies of our group on the identification of the osteoblastic differentiation at the molecular level have revealed that Osteocalcin mRNA can be detected both in osteosarcoma cells and in non-skeletal tumor cell lines. In order to provide a reliable means of molecular tumor characterisation, thorough comparative studies on fresh and paraffin material of larger tumor series are in progress.
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PMID:[Bone matrix production in osteosarcoma]. 1009 26

SPARC is known to be important in development and tissue remodelling. Here, we examined the effects of SPARC (secreted protein, acidic and rich in cysteine; osteonectin) derived from a rat osteosarcoma cell line on migration of renal cell carcinoma (RCC) by a Boyden chamber assay. YCR RCC cells migrated through type IV collagen-coated filters without stimuli (basal level). SPARC in the lower compartment stimulated chemotactic activity to 120% of the basal level, whereas premixing of YCR with purified SPARC before inoculation reduced their migration to 72% of the basal level. Furthermore, SPARC mixed with type IV collagen more efficiently stimulated their migration in a concentration-dependent manner (up to 170% of the basal level). This suggests that SPARC bound to type IV collagen plays a role in tumor invasion.
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PMID:Stimulation of motility of human renal cell carcinoma by SPARC/Osteonectin/BM-40 associated with type IV collagen. 1036 90

Multilayered coatings composed of mixtures of hydroxyapatite (HA) and P(2)O(5)-based bioactive glasses offer potential clinical benefits in orthopedic and dental surgery. In this study double-layer plasma-sprayed coatings were prepared and the biological response evaluated in tissue culture using two human osteosarcoma cell lines, MG63 and HOS TE85 (HOS). The cells were cultured on the materials and the effects on cell growth were determined using a spectrophometric assay of a mitochondrial enzyme that is active in viable cells. While none of the materials influenced the growth of the MG63 cells, the HOS cells appeared to undergo less proliferation on all the HA materials. Flow cytometry analysis was carried out using rabbit antibodies against osteonectin, osteopontin, bone sialoprotein, fibronectin, and collagen type I to measure the effects of the materials on key cellular functions. The results showed that the materials downregulated the expression of these extracellular matrix antigens by MG63 cells whereas they had less effect on the HOS cells compared to the same cells incubated on a plastic surface. Notably, with both cell lines the composite with the higher percentage of glass restored the production of connective tissue proteins to levels that were more similar to those present in the control cells.
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PMID:Flow cytometry analysis of effects of glass on response of osteosarcoma cells to plasma-sprayed hydroxyapatite/CaO-P(2)O(5) coatings. 1049 97

While the analysis of the clinical, radiologic, and histopathologic features of surface osteosarcomas has been the subject of several papers, identification of the phenotypic features of these tumors has so far received little attention. The aim of the present study was to characterize the neoplastic cells of surface osteosarcomas using an ultrastructural and immunohistochemical approach. Glutaraldehyde-fixed, epoxy resin-embedded archival pieces of tissue from 8 surface osteosarcomas (4 parosteal low-grade osteosarcomas, 3 dedifferentiated parosteal osteosarcomas, 1 periosteal osteosarcoma) were investigated using transmission electron microscopy. Sections of formalin-fixed, paraffin-embedded tumor specimens were employed for the immunohistochemical analysis of osteonectin and osteocalcin, two markers of cells of osteoblastic lineage, and sigma-smooth muscle actin and muscle specific actin. By electron microscopy, the tumors were composed of a mixture of neoplastic cells with varied differentiation, i.e., osteoblast-like, fibroblast-like, myofibroblast-like, and chondroblast-like. The latter were particularly abundant in the periosteal osteosarcoma. Osteocalcin expression was detected in the cytoplasm of neoplastic cells in 6 cases (66.6%), while osteonectin was expressed at least focally in all cases. The expression of the noncollagenous bone proteins was higher in low-grade osteosarcomas than in dedifferentiated osteosarcomas. sigma-Smooth muscle actin and muscle-specific actin expression were detected in 4 (44.4%) and 5 (55.5%) cases respectively, and the distribution was similar in both low-grade and dedifferentiated lesions. The results do not confirm previous observations regarding the prevalence of a specific cellular phenotype in surface osteosarcomas. Further, the myofibroblast-like cells that are present in variable numbers in these tumors are probably modified osteoblasts, since they co-express actin, osteonectin, and osteocalcin.
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PMID:Submicroscopic and immunohistochemical profile of surface osteosarcomas. 1050 42


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