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 main deficiency of rapid intra-operative histological diagnosis of bone tumours is the possibility of biopsy error. If this is avoided, rapid sections can be made from tumour biopsy specimens either with the simple freeze-microtome or a cryostat. The specially thin cryostat sections are particularly suitable for revealing cytological details and may be superior even to paraffin sections. On the other hand, cell-deficient tumours with a great deal of intercellular substance or carcinoma metastases can be diagnosed more reliably from usual frozen section than cryostat section. Considerable experience is required to avoid misdiagnosis. One of the most difficult problems is the diagnosis of chondromas of the long bones and the pelvis. The term "semimalignancy" is a suitable one for many forms of those giant-cell tumours which have special tendency towards recurrence even after years. Dangers and limitations of the rapid diagnosis of bone tumour are demonstrated most clearly on purely histomorphological assessment, without knowledge of history, clinical findings or X-ray diagnosis. This is especially striking in the case of fracture callus which may be misdiagnosed as osteosarcoma.
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PMID:[Rapid intra-operative histological diagnosis of bone tumours (author's transl)]. 26 29

The morphologic events and macromolecular interactions in matrix-induced bone formation are comparable with those occurring in the development of fracture callus. Thus, bone induction by decalcified bone matrix is an experimental model for fracture healing and a new tool for research concerning the biochemistry of bone cell differentiation. Three conditions are necessary for bone cell differentiation in postnatal life: (1) a three-dimensional pattern of proliferation of mesenchymal cells; (2) anchorage-dependent microvilli extending the proliferating cells; and (3) a locally released bone morphogenetic protein (BMP). To date, BMP with a molecular weight of 17,500-18,500 daltons has been isolated from bone, and a BMP-like protein with a molecular weight of 22,000 daltons has been extracted from mouse osteosarcoma. It is difficult to separate BMP, a collagenase-resistant, trypsin-labile acidic polypeptide, from several other low molecular weight proteins.
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PMID:Postnatal new bone formation. 670 31

Stress fractures of the femoral diaphysis in young children are rare. Pain and an antalgic gait are the most common features. There is usually no history of either trauma or a recent increase in physical activities. Initial radiographs may be normal. Technetium bone scanning is the most sensitive method of early diagnosis, but may not be diagnostic. Computed tomography and magnetic resonance imaging are useful in early confirmation of the diagnosis. Serial radiographs will show maturation of the periosteal new bone with evidence of repair. Biopsy should be avoided, except in cases of obvious neoplasm shown by computed tomography or magnetic resonance imaging, or in cases with progressive cortical destruction shown on serial radiographs, because fracture callus may be difficult to distinguish from osteosarcoma. Treatment consists of protected weight bearing and activity restriction until resolution of symptoms and radiographic evidence of healing.
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PMID:Stress fractures of the femoral diaphysis in young children. A report of 2 cases. 764 34

Interstitial collagenase plays an important role in both the normal and pathological remodeling of collagenous extracellular matrices, including skeletal tissues. The enzyme is a member of the family of matrix metalloproteinases. Only one rodent interstitial collagenase has been found but there are two human enzymes, human collagenase-1 and -3, the latter being the homologue of the rat enzyme. In developing rat and mouse bone, collagenase is expressed by hypertrophic chondrocytes, osteoblasts, and osteocytes, a situation that is replicated in a fracture callus. Cultured osteoblasts derived from neonatal rat calvariae show greater amounts of collagenase transcripts late in differentiation. These levels can be regulated by parathyroid hormone (PTH), retinoic acid, and insulin-like growth factors, as well as the degree of matrix mineralization. Much of the work on collagenase in bone has been derived from studies on the rat osteosarcoma cell line, UMR 106-01. All bone-resorbing agents stimulate these cells to produce collagenase mRNA and protein, with PTH being the most potent stimulator. Determination of secreted levels of collagenase has been difficult because UMR cells, normal rat osteoblasts, and rat fibroblasts possess a scavenger receptor that removes the enzyme from the extracellular space, internalizes and degrades it, thus imposing another level of control. PTH can also regulate the abundance of the receptor as well as the expression and synthesis of the enzyme. Regulation of the collagenase gene by PTH appears to involve the cAMP pathway as well as a primary response gene, possibly Fos, which then contributes to induction of the collagenase gene. The rat collagenase gene contains an activator protein-1 sequence that is necessary for basal expression, but other promoter regions may also participate in PTH regulation. Thus, there are many levels of regulation of collagenase in bone perhaps constraining what would otherwise be a rampant enzyme.
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PMID:The regulation and regulatory role of collagenase in bone. 888 5

The authors report a rare case of juxtacortical osteosarcoma of the radius in a child. The diagnosis and treatment were delayed because of misleading and wrongly reassuring radiological and histological aspects. The 12-year-old boy was admitted for a tumefaction of the proximal extremity of the right radius noticed after trauma. Physical examination showed a hard and slightly painful swelling. Xrays showed an irregular osseous mass developed from the superior metaphysis of the radius and encircling it. MRI showed a juxtacortical tumor with medullary involvement. A biopsy concluded to a fracture callus. Ten months later, the tumor became painful and homogeneous, regular and well defined on Xrays. A repeat biopsy showed juxtacortical osteosarcoma. Enbloc resection of the tumor was done. After a follow-up of 2 years, the child is alive without recurrence and metastasis and with a satisfactory function of the upper limb.
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PMID:[Juxtacortical osteosarcoma of the radius in a child]. 1241 46

Fine-needle aspiration (FNA) is a reliable, safe, and cost-effective procedure with a well-established role in the diagnosis of various solid tissue neoplasms. The role of FNA in the diagnosis of primary bone tumors, including osteosarcoma (OGS), is controversial and has yet to be established. We reviewed our experience with the use of FNA as a diagnostic technique over the past 8 yr at our institution. Diagnosis was conclusive in 26 (65%) of 40 patients, 18 of whom went to neoadjuvant therapy and/or resection based solely on the FNA interpretation of either "high grade sarcoma" or "osteosarcoma." Of the remaining 14 (25%) patients, 12 had inconclusive diagnosis and two (5%) were false-negatives. An inconclusive diagnosis was most likely to be an inadequate or paucicellular aspirate, seen in six (15%) patients. An additional six patients had variants of osteosarcoma (four chondroid, one "giant cell rich," one parosteal) that made definitive diagnosis impossible. The two that were incorrectly classified were diagnosed as fracture callus and plasmacytoma. FNA is an accurate and cost-effective tool for the initial diagnosis of primary osteosarcoma with a sensitivity of 65% and accuracy of 95%. Inconclusive diagnoses are likely to be due to insufficient sample cellularity or the presence of OGS variant. In our experience, FNA is sufficient to provide the diagnosis of OGS prior to definitive treatment when interpreted in conjunction with imaging studies and clinical findings. In those cases where FNA fails to yield a diagnostic sample, a traditional biopsy can be performed.
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PMID:Utility of fine-needle aspiration in the diagnosis of primary osteosarcoma. 1245 65

Murine mesenchymal stem cells are capable of differentiation into multiple cell types both in vitro and in vivo and may be good candidates to use as cell therapy for diseased or damaged organs. We have previously reported a method of enriching a population of murine MSCs that demonstrated a diverse differentiation potential both in vitro and in vivo. In this study, we show that this enriched population of murine mesenchymal stem cells embolize within lung capillaries following systemic injection and then rapidly expand within, and invade into, the lung parenchyma, forming tumor nodules. These lesions rarely contain cells bearing the immunohistochemical characteristics of lung epithelium, but they do show the characteristics of immature bone and cartilage that resembles exuberant fracture callus or well-differentiated osteosarcoma. Our findings indicate that murine mesenchymal stem cells can behave in a manner similar to tumor cells, with dysregulated growth and aberrant differentiation within the alveolar microenvironment after four passages. We demonstrate that unlike human MSCs, MSCs from different mouse strains can acquire chromosomal abnormalities after only a few in vitro passages. Moreover, other parameters, such as mouse strain used, might also play a role in the induction of these tumors. These findings might be clinically relevant for future stem cell therapy studies. Disclosure of potential conflicts of interest is found at the end of this article.
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PMID:Murine but not human mesenchymal stem cells generate osteosarcoma-like lesions in the lung. 1736 52

Accumulating evidence suggests that cyclooxygenase (COX)-2 is involved in the pathogenesis of human and canine osteosarcoma. The aim of this study was to investigate the expression of COX-2 in normal, reactive and neoplastic canine bone and the events downstream to COX-2 that lead to prostaglandin E(2) (PGE(2)) production. COX-2, microsomal PGE(2) synthase-1 (mPGES-1) and the PGE(2) receptor (EP2) were assessed by immunohistochemistry in 12 samples of normal bone, 14 cases of fracture callus and 27 appendicular osteosarcomas. No immunoreactivity to COX-2, mPGES-1 or EP2 receptor was observed in normal bone. Fifty percent of reactive bone samples expressed COX-2 and 57% expressed mPGES-1 and EP2 receptor, although with weak labelling intensity. Ninety-three percent of osteosarcomas expressed COX-2, while mPGES-1 was expressed by 85% and EP2 receptor by 89% of the tumours. The data confirm that COX-2 is expressed at high level in osteosarcoma and support the use of COX-2 inhibitors to improve the response to chemotherapy. The possibility of blocking the EP2 or the selective inhibition of mPGES-1, rather than COX-2 activity, might decrease the incidence of adverse effects that occur due to the inhibition of prostanoids other than PGE(2).
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PMID:Immunohistochemical expression of COX-2, mPGES and EP2 receptor in normal and reactive canine bone and in canine osteosarcoma. 2263 46

A case of potentially dedifferentiated parosteal osteosarcoma was found in the proximal humerus of an adult female buried in the late Anglo-Saxon cemetery of Cherry Hinton, Cambridgeshire, UK. Key features include a large, dense, lobulated mass attached to the medial metaphysis of the proximal humerus by a broad-based attachment, accompanied by cortical destruction and widespread spiculated periosteal reaction. Radiographic images confirm medullary involvement, lack of continuity between the cortex and external mass, a radiolucent cleavage plane and possible radiolucent zones within the bony masses. Differential diagnoses considered include osteochondroma, myositis ossificans, fracture callus, as well as the primary malignancies of osteosarcoma and chondrosarcoma, and their various subtypes. The macroscopic and radiographic analysis of the tumor is described and discussed within clinical and paleopathological contexts. One of only 19 uncontested examples of osteosarcoma from past human populations, most of which remain unconfirmed, this case represents what we believe to be the earliest, and probably singular, bioarcheological example of parosteal osteosarcoma in human history.
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PMID:On the importance of considering disease subtypes: Earliest detection of a parosteal osteosarcoma? Differential diagnosis of an osteosarcoma in an Anglo-Saxon female. 2977 80