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

Metastatic osteosarcoma is a potential target for gene therapy, because conventional therapies are only palliative and metastatic disease is invariably fatal. Overexpression of the cyclin G1 (CYCG1) gene is frequently observed in human osteosarcoma cells, and its continued expression is found to be essential for their survival. Previously, we reported that down-regulation of cyclin G1 protein expression induced cytostatic and cytocidal effects in human MG-63 osteosarcoma cells (Skotzko et al., Cancer Research, 1995). Here, we extend these findings in a tumorigenic MNNG/HOS cell line and report on the effective inhibition of tumor growth in vivo by an antisense cyclin G1 retroviral vector when delivered as concentrated high titer vector supernatants directly into rapidly growing subcutaneous tumors in athymic nude mice. Histologic sections from the antisense cyclin G1 vector-treated tumors showed decreased mitotic indices and increased stroma formation within the residual tumors. Furthermore, in situ analysis of the cell-cycle kinetics of residual tumor cells revealed a decrease in the number of cells in S and G2/M phases of the cell cycle concomittant with an accumulation of cells in the G1 phase. Taken together, these studies demonstrate in vivo efficacy of a high-titer antisense cyclin G1 retroviral vector in an animal model of osteosarcoma.
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PMID:Retroviral vector-mediated transfer of an antisense cyclin G1 construct inhibits osteosarcoma tumor growth in nude mice. 932 69

This article focuses on major clinical and imaging features that are of practical interest in the diagnosis and management of osteosarcoma, a malignant tumor arising from the osteogenic matrix. The current histologic classification of this tumor is also reported. Different types of osteosarcoma are described, each of them with a definite clinical and radiographic pattern. Conventional radiography is the keystone to diagnosis because it allows analysis of the patterns relevant to the different lesions (location, site, bone destruction, periostal reaction, soft tissue masses). The most common type of osteosarcoma is defined classic or conventional high grade (75%) and it typically involves the medullary cavity. Radiographically, it may be predominantly osteosclerotic or osteolytic, but more frequently it has a mixed (osteoslerotic/osteolytic) pattern. The teleangiectatic osteosarcoma is an aggressive form (5%) characterized by marked vascularization with large blood-filled cystic cavities; its typical radiographic pattern is purely osteolytic. Juxtacortical osteosarcoma (8-10%) indicates a group of osteosarcomas apparently arising on bone surface. The most common type is parosteal osteosarcoma which affects older subjects and has a better prognosis than the classic type. Radiography shows a heavily ossified mass with a broad base attached to the underlying cortex. CT and MRI are useful in the differential diagnosis of osteosarcoma and myositis ossificans or osteocondroma. Rare types of osteosarcoma include the periosteal and high-grade surface variants, as well as secondary and multifocal osteosarcoma (osteosarcomatosis). CT and MRI are the imaging procedures of choice in locoregional staging (intraosseous and extraosseous spread, skip metastases, growth plate and articular involvement). CT of the chest is a useful tool for detecting lung metastases. Also MRI has a role in monitoring the response to chemotherapy and in detecting recurrence. It permits a more accurate study of the tumor volume than other imaging techniques and clinical examination. MRI becomes even more useful when paramagnetic contrast agents are administered because dynamic MRI with contrast enhancement help differentiate postchemotherapy changes from viable tumor--the latter enhancing rapidly and the former slowly. Thus, dynamic MRI allows a precise mapping of any residual tumor activity.
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PMID:Malignant tumors of the osteogenic matrix. 965 9

The role and value of chemotherapy for soft tissue sarcomas remain unclear. Seventeen patients with pulmonary metastatic soft tissue sarcomas underwent treatment with chemotherapy, and the clinical efficacy and prognosis were studied. Six patients with synovial sarcomas, 4 with malignant fibrous histiocytomas, 4 with neurosarcomas, and the remaining 3 patients with leiomyosarcoma, extraskeletal osteosarcoma, and extraskeletal chondrosarcoma, were studied. Cases with small round cell sarcomas were excluded. The chemotherapy agents were ifosfamide in 10 cases, combination of ifosfamide and adriamycin in 5 cases, or cisplatin and adriamycin in 2 cases. Of the 17 patients, seven had partial responses radiographically and five had pulmonary metastases from synovial sarcoma. Eight patients underwent resection of pulmonary metastases following chemotherapy, and they were found to be residual tumor cells histologically. Twelve of the patients died of disease at 6-108 months (median, 30 months) from the time of the initial therapy, and five patients have survived from 1-53 months (median, 30 months). The absolute three-year survival rate, according to the Kaplan-Meier method, for all 17 patients was 39%. In the two cases with no change and progressive disease, all patients were dead within 2 years, while in the seven partial response cases, two patients were dead, four were alive with pulmonary metastases, and only one case was disease-free at this writing. The survival rate for patients with partial response was significantly higher than for patients with no response. Although the cure rate of pulmonary metastatic soft tissue sarcomas is still low, the combination of chemotherapy and surgery has been shown to result in prolonged survival.
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PMID:[Chemotherapy for pulmonary metastases of soft tissue sarcoma]. 975 95

Metastatic osteosarcoma most commonly affects the lungs and other bones. Hepatic metastasis at the time of diagnosis is extremely rare. A 14-year-old boy with synovial sarcoma of the left popliteal fossa was treated with surgical resection, radiotherapy for microscopic residual disease, and 1 year of chemotherapy (vincristine, cyclophosphamide, dactinomycin, and doxorubicin). Approximately 10 years after the initial diagnosis, a secondary osteosarcoma developed in the left proximal tibia. Computed tomography at presentation showed bilateral pulmonary metastases and large ossified nodules in the liver that demonstrated abnormal avidity on 99mTc MDP bone scan indicating hepatic metastasis. Despite chemotherapy (cisplatin, ifosfamide, high-dose methotrexate, and dacarbazine), the patient died of progressive disease 4 months after the diagnosis of the second cancer. Hepatic metastasis was found at the time of diagnosis of a secondary osteosarcoma and manifested as ossified nodules. The risk of radiation-induced osteosarcoma should always be considered in decisions about treatment for soft-tissue sarcoma.
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PMID:Metastatic osteosarcoma to the liver after treatment for synovial sarcoma: a case report. 1125 30

Radiation-induced sarcomas can originate in either the irradiated bone or soft tissues. Most of these tumors are high-grade. The most common histologic subtypes are malignant fibrous histiocytoma (MFH) and osteosarcoma, although other histologies (eg, angiosarcoma, rhabdomyosarcoma) can occur. Tumor size and grade are the two most important prognostic factors for soft tissue sarcomas, including those associated with radiation therapy. The therapy is therefore dictated by the risk of distant metastases. High-grade tumors that are larger than 5 cm should be treated with primary chemotherapy followed by a margin-negative surgical excision of the residual disease. All low-grade tumors and high-grade tumors 5 cm or smaller should be treated with a margin-negative surgical excision, and systemic chemotherapy should be considered when a negative margin is difficult or impossible to accomplish. Radiation-induced sarcomas (either MFH or osteosarcoma) originating in bone should be approached with primary chemotherapy followed by a margin-negative excision similar to de novo bone sarcomas. The dose-intensity of the active agents should be adjusted appropriately for the age, performance status, and prior therapy in a given patient.
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PMID:Radiation-induced sarcoma. 1205 68

Telomeres, which are important for maintaining chromosome integrity and functions, shorten with each cell division. Telomerase, responsible for telomere synthesis, is expressed in approximately 90% of human tumor cells but seldom in normal somatic cells. This study evaluated the hypothesis that simultaneous shortening of telomeres and inhibition of telomerase results in synergistic and tumor-selective cytotoxicity. In telomerase-positive human pharynx FaDu tumor cells, paclitaxel caused telomere erosion (first detected at 1 h) and apoptosis. Expression of antisense to the RNA component of human telomerase (hTR) inhibited telomerase activity, shortened telomere length, reduced cell growth rate, and resulted in a significant higher sensitivity to paclitaxel. Another telomerase inhibitor, 3'-azido-3'-deoxythymidine (AZT), at a concentration that produced little or no cell detachment or apoptosis, inhibited the telomerase activity and enhanced the paclitaxel-induced cell detachment and apoptosis. AZT also enhanced the activity of paclitaxel in mice bearing well-established s.c. FaDu xenograft tumors (i.e., reduced residual tumor size, enhanced apoptotic cell fraction, and prolonged survival time), without enhancing host toxicity. In contrast, AZT did not enhance the paclitaxel activity in the telomerase-negative osteosarcoma Saos-2 cells nor in FaDu cells where telomerase was already suppressed by antisense hTR, confirming that the AZT effect in parent FaDu cells is mediated through telomerase inhibition. These results demonstrate that combined use of agents targeting both telomere and telomerase yielded synergistic activity selective for tumors that depend on telomerase for telomere maintenance.
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PMID:Simultaneous targeting of telomeres and telomerase as a cancer therapeutic approach. 1256 99

A photodynamic therapy technique with acridine orange (AO-PDT) was experimentally developed and applied clinically to musculoskeletal sarcoma patients to reduce the surgical margin and obtain good limb function. Furthermore, various modalities to enhance and strengthen the cytocidal effect of AO-PDT were investigated. A recent report revealed that the use of stronger unfiltered xenon light in AO-PDT enhanced the cytocidal efficacy of this treatment modality. Therefore, in this study, we investigated whether the use of a flash wave light (FWL) from a xenon lamp, as compared to that of the conventional continuous wave light (CWL), might enhance the cytocidal effect of AO-PDT, using the mouse osteosarcoma cell line, LM8. For an equal energy dose (79.6 joules/cm2), AO-PDT using FWL (10 minutes excitation) was found to exert a significantly stronger cytocidal effect than that using CWL (18 seconds excitation). For the same excitation time (10 minutes' excitation), the use of FWL (79.6 jouleslcm2) was associated with a significantly stronger cytocidal effect of AO-PDT than that of CWL (3,820 joules/cm2). These results reveal that the use of FWL entails the need for a lower excitation energy and shorter excitation time than that of CWL for the cytocidal effect of AO-PDT to be observed against the osteosarcoma cells. In addition, FWL also has the advantage of generating low heat and of having the ability to homogenously illuminate a wider area. We therefore concluded that FWL is more useful for AO-PDT than CWL in terms of saving on the excitation time and of obtaining good efficacy of destruction of the residual tumor in the treatment of musculoskeletal sarcomas.
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PMID:Flash wave light strongly enhanced the cytocidal effect of photodynamic therapy with acridine orange on a mouse osteosarcoma cell line. 1797 79

Osteosarcoma is an aggressive tumor of mesenchymal origin, capable of producing osteoid and immature bone. It is the most frequent primary malignant skeletal neoplasm in children and adolescents. Imaging studies play a major role in initial diagnosis, staging, and assessment of tumor response to chemotherapy. Conventional radiography is the prime imaging modality for diagnosis of bony tumors. Radionuclide bone scan is used in detection of metastatic lesions in the other bones. Computed tomography may be used as an adjunct to conventional radiography, but its main role is detection of pulmonary metastasis. The standard magnetic resonance imaging is the most specific modality for local staging and monitoring response to chemotherapy, and distinguishing postsurgical changes from residual tumor. Dynamic contrast-enhanced magnetic resonance imaging has been introduced to quantify the percentage of tumor necrosis, identify early responders, and thus predict survival. The role of 18F fluorodeoxyglucose positron emission tomography (PET) in the staging and management of osteosarcoma is evolving. It has the advantage of total body imaging and may have an overall role in tumor staging and grading, detection of early response, and therefore, in the prognosis and detection of recurrence.
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PMID:Imaging assessment of osteosarcoma in childhood and adolescence: diagnosis, staging, and evaluating response to chemotherapy. 2021 85

Sclerosing epithelioid fibrosarcoma (SEF) has distinctive morphology and occurs mainly in deep soft tissue of adult extremities. Approximately 59 cases of SEF have been reported, with only 12 previously described in head and neck locations. Lesions involving the oral and maxillofacial region (OMFR) and intraosseous examples are rare. We present five cases of OMFRSEF. The OMF Pathology Department Registry was searched for cases coded from 1990 to the present as "SEF," "fibrosarcoma not otherwise specified" or "neoplasm of uncertain histiogenesis." Inclusion required OMFR location, an abundantly sclerotic sarcoma with epithelioid features, and lack of other phenotype by immunohistochemistry. Five cases of SEF included 3 males and 2 females. The age of the patients were: 19, 22, 35, 47 and 47 years. Tumor location included the infra-temporal fossa, buccal mucosa (recurrence extending into bone), anterior mandible (intraosseous primary, focally extending into soft tissue), and left parotid and submandibular gland (with metaplastic bone) regions. Tumor sizes ranged from 1.0 to 5.7 cm, median 3.5 cm. Histologically, the tumors were well delineated and multinodular, separated by fibrous septae. The spindled to primarily epithelioid tumor cells formed moderately cellular sheets and cords of irregularly contoured medium to large, round to oval, occasionally overlapping nuclei, indistinct nucleoli, wispy eosinophilic (retracting) cytoplasm, and distinctive cytoplasmic borders, embedded in osteoid-like stroma. Hemangiopericytoid (HPC-like) vessels were observed. Despite numerous apoptotic cells, mitoses were generally low; necrosis was present in two cases. Three tumors were graded as 2/3 and two 1/3. Immunohistochemically, the tumor cells were positive for vimentin, 1 case focally for CD34, whereas all cases were negative for S100 protein, keratins, EMA, desmin, and SMA. Wide or radical excision was performed with no adjuvant therapy. Follow-up revealed that 4 cases recurred at a range of 12-120 months. One case had no recurrent/residual disease at 3 months. Metastatic disease was present in 2 cases, to chest wall and lumbar/thoracic spine at 12 and 21 months, respectively. One patient died of disease complications at 15 months. OMFRSEF occur in adults in various locations, but with a common propensity to involve bone; there is recurrent potential and morbidity with higher grade lesions. The differential diagnosis for these tumors in this site includes sclerosing carcinoma, Ewing/PNET, osteosarcoma, osteoblastoma, and benign and malignant myoepithelial salivary gland tumors. The collagen, focal spindle cell features, HPC-like vasculature, and weak focal CD34 reactivity in one case might have raised a possible relationship between OMFRSEF and low grade malignant solitary fibrous tumor, but the intraosseous propensity, epithelioid features and relative lack of CD34 make this a distinctive entity.
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PMID:Oral and maxillofacial sclerosing epithelioid fibrosarcoma: report of five cases. 2061 75

The Colony-Stimulating Factors (CSFs) are undergoing clinical trials for their ability to stimulate the regeneration of bone marrow in patients receiving anticancer chemotherapy. However, the reported effects on the growth of tumor cell lines of different derivations, including osteosarcoma, raise the possibility that the use of these cytokines may induce proliferative effects also in residual tumor cells. In this study, we have used a panel of 12 human osteosarcoma (2 cell lines and 10 primary cultures) and 7 Ewing's sarcoma cell lines (5 cell lines and 2 primary cultures) to evaluate the presence of the G-CSF receptor by RT-PCR and the effects of recombinant Human (rHu) G-CSF on their in vitro growth ability. RT-PCR did not reveal the presence of G-CSF receptor band in any of the osteosarcoma or Ewing's cell lines examined. Moreover, after exposure to rHuG-CSF, no significant stimulatory or inhibitory effects were observed in any of the cell lines. Therefore, G-CSF may be safely used to stimulate marrow regeneration after high-dose chemotherapy both in osteosarcoma and in Ewing's sarcoma.
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PMID:Absence of stimulatory effect of g-csf on the growth of human sarcoma-cells. 2155 32


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