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)

A transplantable osteogenic sarcoma originally arising in the right femur of an AKR/Ms male mouse is described. The original tumor showed a conspicuous bone and cartilage formation, but the capability of forming the bone was lost in the 4th transplant generation and that of cartilage formation was lost in the 7th generation. Alkaline phosphatase activity was histochemically demonstrated in only a few tumor cells, and the activity did not rise in the host serum. Intracisternal type-A particles of an average diameter of 70 nm were abundant in the rough endoplasmic reticulum, while type-C particles were rarely found to be budding from the cell surface or free in the extracellular spaces by electron microscopy. Three of the 27 thymectomized AKR mice that had been neonatally injected with cell-free material of the transplanted tumor developed osteomas, but no osteogenic sarcoma was found.
 ...
PMID:A spontaneous transplantable osteogenic sarcoma in AKR/Ms mice. 19 24

Malignant fibrous histiocytomas are well-described tumors of the soft tissues. Recent investigations have shown that malignant histiocytoma may also occur as a primary bone tumor. However, difficulties may arise to distinguish malignant histiocytoma of bone from other malignant bone tumors, such as osteosarcoma. In the present study, the ultrastructure of five cases of malignant fibrous histiocytoma of bone is compared with that of osteosarcoma. The results show that malignant fibrous histiocytoma is composed mainly of histiocytic cells and fibroblastic cells. In addition, xanthomatous cells, undifferentiated cells, and giant cells may be observed. By contrast, the predominant cell type in osteosarcoma is the neoplastic osteoblast, characterized by abundant rough endoplasmic reticulum. Signs of matrix calcification in the intercellular matrix between the collagen fibrils are regularly observed in osteosarcoma, but not in malignant histiocytoma. From these results it is concluded that the ultrastructure of malignant fibrous histiocytoma arising in bone is morphologically identical with the soft tissue counterpart of this tumor. The components of the tumor are derived from neoplastic histiocytes. This cytogenesis differs from that of osteosarcoma, which is derived from neoplastic osteoblasts. Therefore, from the ultrastructural point of view, malignant fibrous histiocytoma of bone should be accepted as a distinct histologic entity among bone tumors.
 ...
PMID:Malignant fibrous histiocytoma of bone and osteosarcoma. A comparative light and electron microscopic study. 22 75

Light microscopic, histochemical and ultrastructural studies of a transplantable mouse osteosarcoma were carried out. The osteosarcoma grew in CBA mice after injection of cultured cells derived from a Dunn osteosarcoma. The tumour differed from the original Dunn osteosarcoma with respect to metastatic potential and structural features. The transplantable tumour was an anaplastic, richly vascularized fibroblastic osteosarcoma with alkaline phosphatase activity and rather sparse osteoid formation, resulting in death of the animals within 6 to 8 weeks. Virus particles were found intracellularly, mainly localized to cisterns of rough endoplasmic reticulum, and extracellularly often close to plasma membranes and collagen fibres. Sign suggestive of formation of collagen fibres by tumour cells were observed. A possible viral influence upon the tumour was suggested also by its growth behaviour in vitro. The results indicate that this new transplantable tumour, obtained in an allogenic system, represents a clonal derivative of the original Dunn osteosarcoma.
 ...
PMID:Transplantable osteosarcoma in mice. Structural characterization of a transplantable osteosarcoma obtained in an allogenic system. 29 21

An osteogenic sarcoma arose in the right orbit of a 7-year-old boy some 5 years after the right orbit had been treated by four courses of radiotherapy (total dose approximately 13,000 rads) for a multicentric retinoblastoma. Death occurred 6 months after the orbital tumor was first detected. Study of the orbital tumor by electron microscopy revealed a cell population of varied morphology in which two main types were identified. In one group, the cells were large with radiolucent cytoplasm, which contained long branching segments of rough endoplasmic reticulum. In the second group, the cells were smaller with irregular nuclei and an electron-dense cytoplasm, which contained short segments of dilated rough endoplasmic reticulum and numerous mitochondria. The first group of cells closely resembled osteoblasts, while the second group had some features of osteoclasts or their percursors. The branching processes of the tumor cells were separated by an amorphous ground substance, which contained collagen-like fibrils and hydroxyapatite crystals. Crystal deposition was in some instances in close relation to extracellular membrane-bound vesicles.
 ...
PMID:Fine structure of a radiation-induced osteogenic sarcoma. 105 46

The ultrastructural features of 20 cases of osteosarcoma are discussed. Characteristically, the malignant cells (osteoblasts) contained large quantities of dilated, anastomosing rough endoplasmic reticulum, ofter forming large lakes. Mitochondria were sparse. Similar features are seen in osteoblasts in normal developing bone. Marked ultrastructural similarities of cells from chondrosarcomatous, fibrosarcomatous and typical osteosarcomatous areas of these tumors strongly supports the concept that these neoplastic cells all arise from the same progenitor cell. Malignant giant cells were readily differentiated from benign osteoclasts. The most significant ultrastructural findings were the varying degrees of calcification in the intercellular areas (osteoid), ranging from an extensive dense deposition of hydroxyapatite crystals which obscured the underlying collagen fibers, to focal collectors, or puffs, of slender needle-shaped hydroxyapatite crystals deposited on or along collagen fibers. The earliest apparent evidence of calcification was the presence of small electron-dense particles on or in collagen fibers.
 ...
PMID:The ultrastructure of osteosarcoma. A review of twenty cases. 106 51

Immunohistochemical staining techniques used on an 11-week-old fetus showed that fetal antigen 2 (FA2) was present intracellularly in endochondral and perichondral osteoblasts, and the immunoreaction was extended into the adjacent bone matrix. Osteoclasts and chondroblasts were found to be FA2 negative. A granular perinuclear intracytoplasmic FA2 immunoreaction was found in cultured osteoblasts and osteogenic osteosarcoma cells, and immunoelectron-microscopical examination revealed a granular immunoreaction product in the rough endoplasmic reticulum. These findings indicate that FA2 is synthesized by osteoblasts and osteogenic osteosarcoma cells. A reaction of immunological identity was found between FA2 purified from second trimester amniotic fluid and serum-free supernatants of cultured osteogenic osteosarcoma cells. This shows that an antigen recognized by the anti FA2 antibody is secreted by these malignant cells. Thus, FA2 may represent a marker for altered bone metabolism, and have a potential in the classification of osteogenic osteosarcoma/chondrosarcoma.
 ...
PMID:Fetal antigen 2 (FA2) in human fetal osteoblasts, cultured osteoblasts and osteogenic osteosarcoma cells. 141 76

Functional morphology on the transformation of fibroblasts into chondrocytes induced by bone morphogenetic protein (BMP) was studied by light and electron microscopy using 35S autoradiography and immunohistochemistry for S-100 protein and type-II collagen. A pellet containing BMP obtained from a murine osteosarcoma was transplanted into the mouse subfascia. By 3 days after implantation, many typical fibroblasts, which were free of the silver grains for 35S and devoid of both S-100 protein and type-II collagen, entered the pellet region. By 5 days, the fibroblasts in the pellet region became polygonal in shape, and cytoplasmic vesicles and vacuoles appeared, both containing a homogeneous substance of low electron density. At 5 days, autoradiography revealed many silver grains for 35S over the Golgi apparatus and vesicles and vacuoles of the cells in the pellet region as well as over the surrounding extracellular matrix. Moreover, the cells at 5 days displayed immunoreactivity to both proteins. The extracellular matrix around the cell began to show clear metachromasia and increased in amount with time. At 9 days all the cells in the pellet region were round or oval in shape and surrounded by an abundant cartilaginous matrix. The rough endoplasmic reticulum and Golgi apparatus were extremely well developed, and a large number of vacuoles and vesicles were seen in the cytoplasm. These cells showed intense immunoreactivity to both proteins, and strong accumulation of sulfur was visualized in the extracellular matrix by autoradiography. These results suggest that the fibroblasts in the pellet region change into chondroblasts by 5 days, and become typical chondrocytes by 9 days.
 ...
PMID:Immunohistochemical, autoradiographic and electron microscopic studies on the transformation of fibroblasts into chondrocytes in the mouse subfascia induced by bone morphogenetic protein. 142 6

We describe a case of bone tumor in the left tenth rib that was diagnosed as a low-grade osteosarcoma resembling osteoblastoma. This diagnosis was supported by clinical, radiologic, and histologic findings. Specimens of this tumor were transplanted into nude mice, and the morphology of the transplanted tumors was examined. The transplanted tumors were similar histologically to the parent tumor. Ultrastructurally, the transplanted osteoblasts showed irregular, indented nuclei, dilated endoplasmic reticulum, and varying amounts of intercellular junctional complexes. Our transplantable tumor could be valuable as an experimental model for studies on this tumor type.
 ...
PMID:Osteosarcoma resembling osteoblastoma and its heterotransplantation into nude mice. 155 92

Primary cultures of calvarial derived normal diploid osteoblasts undergo a developmental expression of genes reflecting growth, extracellular matrix maturation, and mineralization during development of multilayered nodules having a bone tissue-like organization. Scanning electron microscopy of the developing cultures indicates the transition from the uniform distribution of cuboidal osteoblasts to multilayered nodules of smaller cells with a pronounced orientation of perinodular cells towards the apex of the nodule. Ultrastructural analysis of the nodule by transmission electron microscopy indicates that the deposition of mineral is confined to the extracellular matrix where cells appear more osteocytic. The cell body contains rough endoplasmic reticulum and golgi, while these intracellular organelles are not present in the developing cellular processes. To understand the regulation of temporally expressed genes requires an understanding of which genes are selectively expressed on a single cell basis as the bone tissue-like organization develops. In situ hybridization analysis using 35S labelled histone gene probes, together with 3H-thymidine labelling and autoradiography, indicate that greater than 98% of the pre-confluent osteoblasts are proliferating. By two weeks, both the foci of multilayered cells and internodular cell regions have down-regulated cell growth associated genes. Post-proliferatively, but not earlier, initial expression of both osteocalcin and osteopontin are restricted to the multilayered nodules where all cells exhibit expression. While total mRNA levels for osteopontin and osteocalcin are coordinately upregulated with an increase in mineral deposition, in situ hybridization has revealed that expression of osteocalcin and osteopontin occurs predominantly in cells associated with the developing nodules. In contrast, proliferating rat osteosarcoma cells (ROS 17/2.8) concomitantly express histone H4, along with osteopontin and osteocalcin. These in situ analyses of gene expression during osteoblast growth and differentiation at the single cell level establish that a population of proliferating calvarial-derived cells subsequently expresses osteopontin and osteocalcin in cells developing into multilayered nodules with a tissue-like organization.
 ...
PMID:Expression of cell growth and bone specific genes at single cell resolution during development of bone tissue-like organization in primary osteoblast cultures. 164 67

A newly established human osteosarcoma cell line, HS-Os-1, from an osteoblastic tumor arising in the left humerus of an 11-year-old girl was morphologically characterized in vitro and in vivo. HS-Os-1 cells in a monolayer have been maintained for more than 2 years since the initial cultivation, and were round or polygonal in shape with marked pleomorphism. Their cytoplasm was strongly positive for specific markers of osteoblasts, such as alkaline phosphatase and osteocalcin. Tumors induced in nude mice by HS-Os-1 cell inoculation at passage 12 or 23 revealed typical histological features of osteoblastic osteosarcoma, similar to those observed in the original tumor, producing prominent osteoid matrix with calcification. Ultrastructurally, HS-Os-1 cells in vitro and tumor cells in vivo showed similar well-developed, markedly dilated rough endoplasmic reticulum, polysomes and microfilaments in their cytoplasm. Additionally, many collagen fibers associated with deposition of electron-dense material were detected in the stroma featuring osteoid matrix. Thus, the HS-Os-1 cell line was shown to exhibit its osteoblastic nature in vitro and in vivo, and therefore might become an extremely useful tool for various pathomorphological investigations on human osteosarcomas.
 ...
PMID:Morphological characterization of a newly established human osteosarcoma cell line, HS-Os-1, revealing its distinct osteoblastic nature. 167 69


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