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 purified human platelet factor 4, a platelet alpha-granule protein, on the growth of the human osteoblastic osteosarcoma cell lines Saos-2 and G-292 was investigated. Platelet factor 4 (20 ng/ml to 2 micrograms/ml) caused a significant, dose-dependent inhibition of human osteoblast-like osteosarcoma cell proliferation. Platelet factor 4 exerted its inhibitory effect under all growth conditions tested: serum-free, serum-stimulated and thrombin-stimulated. The platelet factor 4-induced cell inhibition was not associated with a cytotoxic effect on the cells (assessed by lactate dehydrogenase release). The inhibitory effect of platelet factor 4 was not affected by the presence of indomethacin in the cultures, indicating that the effect was prostaglandin-independent. These results suggest that platelet factor 4 has direct antitumor effects and that it may be important in pathological and physiological processes of bone.
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PMID:Human platelet factor 4 is a direct inhibitor of human osteoblast-like osteosarcoma cell growth. 152 Mar 9

Alterations of blood analyses have been studied at relapse of patients with osteosarcoma and Ewing's sarcoma. The tests included erythrocyte sedimentation rate (ESR), haemoglobin (Hb), leukocyte and thrombocyte counts, gamma glutamyltransferase (GT), lactate dehydrogenase (LD) and alkaline phosphatase (ALP). Sixteen relapsing patients diagnosed from 1970 to 1987 were eligible in each sarcoma group. Median age was 16 years (range 9-30) at diagnosis. The blood tests seemed to be of no help in detecting relapse of osteosarcoma, while ESR, LD and GT rose significantly in relapsing patients with Ewing's sarcoma. ESR was best correlated to disease activity.
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PMID:Alterations of blood analyses at relapse of osteosarcoma and Ewing's sarcoma. 197 22

Of 33 surgical specimens of osteosarcoma obtained from 24 patients, eight were established as transplantable tumor lines in immune-deprived CBA/CaJ inbred mice. Each line retained the histological characteristics of the corresponding primary tumor and produced human lactate dehydrogenase isozymes. Volume doubling times, which ranged from a mean of 12.3 +/- 5.6 to 39.3 +/- 9.8 days, were stable for individual lines over multiple passages. Flow cytometric analysis indicated similar cellular DNA content values in the primary human tumors and established xenograft lines; the presence of two separate stem lines, as in the original tumors, was observed in the laboratory models. Comparison of two methods of immune deprivation indicated that thymectomy, whole-body irradiation, and bone marrow reconstitution was associated with a higher rate of successful engraftment than was thymectomy, 1-beta-D-arabinofuranosylcytosine treatment, and whole-body irradiation. Bone marrow-reconstituted mice also showed less variability in tumor volume doubling time. We conclude that osteosarcoma can be heterotransplanted into bone marrow-reconstituted mice with a relatively high success rate and that the xenografts retain features characteristic of the tumors of origin. The availability of these models should prove useful in the development of new therapeutic regimens and in understanding the biology of osteosarcoma.
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PMID:Development and characterization of pediatric osteosarcoma xenografts. 232 4

Six hundred and fifty-six patients with osteosarcoma of the extremities (107 metastatic and 549 with localized disease) were followed from 2.5 to 20 years (average: 10 years) to evaluate whether their pretreatment serum lactate dehydrogenase (LDH) enzyme levels had a clinical value in predicting the course of the disease. The percentage of patients who had an elevated serum LDH at the time of diagnosis was significantly higher in those patients with metastatic disease than those who had localized disease (64% versus 33%, p < 0.0001). For those who presented with localized disease and had an increased serum LDH level, far more ultimately developed a relapse of disease (60% versus 38%, p < 0.0001) than those patients with a normal pre-treatment value. The prognostic significance of the serum LDH was more pronounced for the 247 patients treated with adjuvant chemotherapy (relapse rate of 72% versus 48%; p < 0.0002) than the 271 patients treated with neoadjuvant chemotherapy (relapse rate: 46% versus 28%, p < 0.005). Following treatment, serum LDH levels almost uniformly returned to normal and no correlation between postoperative levels and relapse of disease could be identified. We have demonstrated that in patients with osteosarcoma of the extremities, pretreatment serum LDH levels have a definite prognostic value which should be considered when comparing the results achieved with different therapeutic protocols and in planning new randomized clinical trials.
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PMID:Prognostic significance of serum lactate dehydrogenase in patients with osteosarcoma of the extremities. 798 4

The mechanisms involved in the mitogenic actions of insulin-like growth factor-I (IGF-I) on skeletal cells are at present unclear. We have investigated the role of glucose-6-phosphate dehydrogenase (G6PD) in this mechanism and provide strong evidence that stimulation of G6PD activity is required for the growth promoting activities of IGF-I. IGF-I (10 ng/ml) significantly elevated G6PD activity in MG-63 human osteosarcoma cells within 30 min which preceded the IGF-I induced DNA synthesis in these cells. Inhibition of G6PD activity by epiandrosterone decreased DNA synthesis in IGF-I stimulated MG-63 cells but this was partly overcome by the addition of a combination of the four deoxyribonucleosides. IGF-I did not cause a general increase in cell metabolism as succinate dehydrogenase and iso-citrate dehydrogenase activity were not altered. Although IGF-I caused a significant increase in lactate dehydrogenase activity this was not inhibited by epiandrosterone. The culture of metatarsals of 4-week-old rats with IGF-I (10 ng/ml) also stimulated G6PD activity in osteoblasts lining the metaphyseal trabeculae.
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PMID:Mitogenic action of insulin-like growth factor-I on human osteosarcoma MG-63 cells and rat osteoblasts maintained in situ: the role of glucose-6-phosphate dehydrogenase. 825 63

Remarkable progress has been made in the treatment of osteosarcoma in the past two decades as a result of the development of effective adjuvant chemotherapy. However, the prognosis is poor in patients with early lung metastases. We review the lactate dehydrogenase release prognostic factor in the development of early lung metastases. This is a retrospective study. Eighteen patients with osteosarcoma were divided in two groups: Group A, patients with normal lactate dehydrogenase and Group B, patients with elevated lactate dehydrogenase. A univaried analysis was established. Ten patients (55%) had elevated levels of lactate dehydrogenase at diagnosis; nine of these patients developed lung metastases in the first twelve months. The difference in patients with normal levels of lactate dehydrogenase was significant (p: 0.02). The value of lactate dehydrogenase as an isolated single factor is limited. It is necessary to consider the tumoral volume, the patient's age and the histologic subtype in the prognosis of these patients, to predict the early development of pulmonary metastatic disease.
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PMID:[Lactic dehydrogenase as a prognostic factor in the development of pulmonary metastatic disease in patients with osteosarcoma]. 896 78

The purpose of this study was to evaluate the prognostic significance of variables in osteosarcoma. We performed a retrospective analysis of 35 patients with non-metastatic limb osteosarcoma that were treated between 1973 and 1994. The following variables were evaluated: age, sex, ethnic group, tumor histology and primary site, alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) levels at diagnosis, treatment regimen, and the histologic response to treatment. Three variables showed significant correlation with prognosis: i) histologic response to preoperative treatment. Disease-free survival (DFS) was 89% in patients with grade III-IV histologic response after a median follow-up (MFU) of 64 months, 67% in patients with grade II after an MFU of 64 months, the patients with grade I response died within 15 months (p<0.0001); ii) treatment regimen. DFS was 83% after an MFU of 42 months, 62% after an MFU of 82 months, and 30% after an MFU of 177 months in patients treated by the 90's, 80's, and 70's protocols, respectively (p<0.05); iii) corrected ALP (cALP) levels at diagnosis. DFS was 78% after an MFU of 88 months in patients with cALP levels <200, and 32% after an MFU of 56 months in patients with cALP levels >200 (p=0.01). Low ALP levels, good histologic response to preoperative chemotherapy, and the new therapeutic regimen correlated with good prognosis in patients with osteosarcoma.
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PMID:Prognostic factors in non-metastatic limb osteosarcoma: A 20-year experience of one center. 1037 13

There is now conclusive evidence that extracellular nucleotides acting via cell surface P2 receptors are important local modulators of bone cell function. Multiple subtypes of P2 receptors have been localized to bone, where their activation modulates multiple processes including osteoblast proliferation, osteoblast-mediated bone formation, and osteoclast formation and resorptive capacity. Locally released nucleotides also have been shown to sensitize surrounding cells to the action of systemic factors such as parathyroid hormone (PTH). In nonskeletal tissue recent attention has focused on one particular P2 receptor, the P2X7 receptor (previously termed P2Z), and its ability to form nonselective aqueous pores in the plasma membrane on prolonged stimulation. Expression of this receptor originally was thought to be restricted to cells of hemopoietic origin, in which it has been implicated in cell fusion, apoptosis, and release of proinflammatory cytokines. However, recent reports have indicated expression of this receptor in cells of stromal origin. In this study, we investigated the expression of the P2X7 receptor in two human osteosarcoma cell lines, as well as several populations of primary human bone-derived cells (HBDCs) at the levels of messenger RNA (mRNA) and protein. We found that there is a subpopulation of osteoblasts that expresses the P2X7 receptor and that these receptors are functional as assessed by monitoring ethidium bromide uptake following pore formation. Inhibition of delayed lactate dehydrogenase (LDH) release in response to the specific agonist 2',3'-(4-benzoyl)-benzoyl-adenosine triphosphate (BzATP) by the nonspecific P2X receptor antagonist PPADS confirmed a receptor-mediated event. After treatment with BzATP SaOS-2 cells exhibited dramatic morphological changes consistent with those observed after P2X7-mediated apoptosis in hemopoietic cells. Dual staining with terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL) and a P2X7-specific monoclonal antibody confirmed the induction of apoptosis in osteoblasts expressing the P2X7 receptor. These data show for the first time the expression of functional P2X7 receptors in a subpopulation of osteoblasts, activation of which can result in ATP-mediated apoptosis.
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PMID:Expression of a P2X7 receptor by a subpopulation of human osteoblasts. 1134 29

As an adjuvant to chemotherapy hyperthermia has proven to be successful as a treatment for osteo- and chondrosarcoma patients. The aim of this study was to investigate whether hyperthermia could increase cellular expression of heat-shock-protein 72 in human osteo- and chondrosarcoma cells and how heat treatment would affect their susceptibility to natural killer cell (NK-cell)-mediated lysis. About 5-10% of the peripheral mononuclear blood cells (PBMC) in the human peripheral blood are natural killer cells (NK-cells). Natural cytotoxicity, mediated by NK-cells, is believed to play an important role in host defense against cancer. The exact mechanisms of recognition of target cells and subsequent NK-cell activation are not yet known. NK-cells, isolated from the peripheral blood of healthy donors, were enriched by magnetic cell-separation to a purity of 85-97%, assessed by FACS-analysis. The susceptibility of heat-treated (42.5 degrees C, 90 minutes) and untreated osteosarcoma (MG63) and chondrosarcoma (HTB94) cell lines to NK-killing was determined by a release assay of lactate dehydrogenase (LDH). Lysis by NK-cells was increased by heat treatment of the target cells from 16.6% + 4.5% to 33% + 15%, p=0.035, for osteosarcoma cells, (E/T ratio of 5:1) and from 13.7% + 3.1% to 27.9% + 16.9%, p=0.021, (E/T ratio of 20:1) for chondrosarcoma cells. An increased expression of HSP72 of chondro- and osteosarcoma cells after heat treatment was detected by the Western blot technique. The results of this study show that hyperthermia increases HSP72 expression in osteo- and chondrosarcoma cells and their susceptibility to NK-cell-mediated lysis. These findings may lead to new therapeutic strategies, using hyperthermia to improve immunological defense against chondro- and osteosarcoma cells.
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PMID:Hyperthermia increases the susceptibility of chondro- and osteosarcoma cells to natural killer cell-mediated lysis. 1201 51

A certain number of pediatric cancer patients still succumb to relapse following conventional treatment of their malignancies. One of the mechanisms of relapse is escape from immunity. Adoptive cellular immunotherapy with effector cells has the potential to overcome this escape. In adults, the CD3+ CD56+ cell, a cytokine-induced killer (CIK) cell, appears to be a promising effector cell type with the greatest cytotoxicity. This effector cell type may work in children as well. No similar studies with children have been published. We speculated that expanded CD3+ CD56+ cells obtained from pediatric cancer patients during remission would act similarly against various pediatric tumor cell lines; therefore, we undertook the present study to find support for our speculation. This study was undertaken to generate and expand CD3+ CD56+ CIK cells from normal peripheral blood mononuclear cells (PBL) obtained from 6 children with cancer (2 with acute lymphoblastic leukemia, 2 with large cell lymphoma, and 2 with osteosarcoma) in remission after intensive chemotherapy and to study the cytotoxic activities of these cells against chronic myeloid leukemia cell line K562 t(9;22), 4 pediatric tumor cell lines [infant acute lymphoblastic leukemia RS4 t(4;11), TEL/AML acute lymphoblastic leukemia REH t(12;21), alveolar rhabdomyosarcoma Rh-Cr t(2;13), and Ewing sarcoma EW-Le t(11;22)], and 2 pediatric glioblastoma multiforme cultured cell lines (G74 and G77). CIK cells were generated and expanded in culture medium to which interferon gamma, monoclonal antibody against CD3, and interleukin 2 were added at appropriate times. Cells were counted by flow cytometry. Net lactate dehydrogenase release from target cells incubated with CIK cells was used as an index of CIK cell cytotoxicity against various pediatric tumor cell lines. The results show that after 21 days in culture CD3+ CD56+ CIK cells derived from the 6 pediatric patients accounted for a median of 28.3% of the entire culture (range, 10.7%-36.4%). Before expansion no such cells were found in any of the 6 children. Median lytic activity rates of CIK cells were 45.5% to 64.5%, rates that contrasted drastically to the lytic activity rates of PBL, which were only 8% to 12%. The findings of the present study are encouraging. They provide information for developing adoptive immunotherapy for future clinical trials with pediatric cancer patients, particularly those patients with minimal residual disease after intensive chemotherapy or stem cell transplantation (especially nonmyeloablative transplantation procedures).
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PMID:Generation of CD3+ CD56+ cytokine-induced killer cells and their in vitro cytotoxicity against pediatric cancer cells. 1262 54


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