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 pathologist must obtain X-rays before attempting to make a diagnosis in a bone tumor. Errors are made with both benign and malignant lesions associated with calluses. Infection may stimulate a malignant bone tumor radiographically and pathologically. Secondary aneurysmal bone cyst may dominate the radiographic and pathologic findings and obscure the primary diagnosis. Osteoblastomas are becoming increasingly difficult to diagnose. The question of whether such an entity can become malignant has not been resolved. Cartilagenous tumors are often difficult to diagnose and the pathologist must not only rely on histologic findings, but in particular pay attention to the radiographic pattern which is often diagnostic. Accuracy of diagnosis in Ewing's sarcoma is essential because the treatment now can result in a cure rate of almost 40%. Certain lesions such as lymphoma or osteosarcoma can mimic this tumor. To re-emphasize the problem, the pathologist must have all the clinical information before attempting a diagnosis of a bone tumor and without the pertinent X-ray, errors are almost inevitable.
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PMID:Common errors made by pathologists in the diagnosis of bone tumors. 107 Jul 17

Chondroprogenitor cells present in the apical and lateral parts of the mandibular condyle from neonatal mice differentiate towards the osteoblastic lineage and form bone within 7 days in culture. Infection of condylar explants with the FBR osteosarcoma virus (FBR MSV) results in the transformation of cells in the progenitor zone, previously identified as the target for the virus, and the formation of a transplantable osteosarcoma-like lesion. Morphological and biochemical changes in this system were investigated in the course of tumor development. Virus infection was followed by a significant increase in cell density and 3H-thymidine incorporation within the progenitor zone at the early stage of culture. In later stages, cell density and 3H-thymidine incorporation were lower than in control tissue. The 3H-thymidine labeling index gave similar results in infected and control tissues until day 7. Then, a significantly higher labeling index was found in the progenitor zone of infected condyles. At this stage, the proliferative effect of the virus even affected the cartilagenous core of the tissue. Quantitative alkaline phosphatase activity increased between day 3 and day 7 and was particularly high in the zone of infected cells. In addition, infected tissues consistently revealed a higher uptake of 45Ca, and deposition of the radioisotope along irregularly formed bone trabecules in the transformed tissue. The results suggest that there is an enhancement of tissue maturation following infection with the FBR osteosarcoma virus. Although biochemical investigations of whole condyles showed few differences in the total values of alkaline phosphatase activity, 3H-thymidine incorporation, DNA content, and 45Ca uptake, the histochemical assays revealed clear differences in the distributional pattern of these parameters within infected and control condyles.
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PMID:Biochemical characterization of a virus-induced osteosarcoma-like osseous lesion in vitro. 255 23

Infection of cells derived from an osteogenic sarcoma (HOS) with human cytomegalovirus (HCMV) resulted in persistent infection. It appears that persistent infection is due to a balance between release of virus and the growth of uninfected cells. Viruses derived from the persistently infected cultures were not temperature sensitive nor were they defective interfering particles. However, hybridization experiments using the Q-labeled probe from the XbaI Q fragment indicated that one copy of the repeat sequences contained in fragments Q and O of CMV, Towne DNA have been completely deleted from the virus DNA derived from the persistent culture. Thus the mechanism of persistent infection is probably due in part to a variant of CMV present in the cultures.
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PMID:A variant of human cytomegalovirus derived from a persistently infected culture. 608 16

Human neurokinin-1 receptor cDNA was introduced into the pSFV1 Semliki Forest virus (SFV) vector and the in vitro transcribed RNA was electroporated into BHK cells with pSFV-Helper RNA. This procedure resulted in the packaging of a high-titer SFV-NK-1 virus stock containing approximately 5 x 10(9) infective units/ml. Infection of baby hamster kidney, COS-7, Chinese hamster ovary and human osteosarcoma cells yielded high levels of human neurokinin-1 receptor expression as assessed by [3H]substance P binding. The maximal receptor expression level obtained was 4 x 10(6) receptors/cell and studies of the post-infection time indicated that a high level of receptor expression was observed 10-24 h post-infection. The human neurokinin-1 receptor expressed in infected baby hamster kidney, COS-7 and Chinese hamster ovary cells was able to stimulate Ca2+ mobilization indicating functional coupling to guanine-nucleotide-binding proteins. The application of the Semliki Forest virus expression system will permit the rapid and efficient production of large quantities of receptor protein for both pharmacological and structural studies.
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PMID:High-level expression of the human neurokinin-1 receptor in mammalian cell lines using the Semliki Forest virus expression system. 752 21

Twenty-one patients underwent sternal resection and reconstruction. Surgical indications included sternal infection in 9 patients, recurrent breast cancer in 6, metastatic carcinoma from an unknown primary in 2, pectus excavatum in 2, and osteogenic sarcoma and eosinophilic granuloma in 1 each. Management included partial sternectomy in 10 patients (group 1) and complete sternectomy in 11 (group 2). Chest wall reconstruction was by various flaps and mesh repairs. Blood transfusions averaged 2 units in group 1 versus 5.5 units in group 2 (p = 0.02). Average number of days until extubation was 2.6 in group 1 versus 7.3 in group 2 (p = 0.04). Average number of intensive care unit days was 4.4 for group 1 versus 9.4 for group 2 (p = 0.03). The number of days until discharge was 14 days for group 1 versus 20 days for group 2. Complications occurred in 40% of group 1 and 82% of group 2 patients. Overall mortality was 9.5%. Sternal resection and reconstruction, particularly complete sternal resections, are a major undertaking with substantial morbidity. Using a multidisciplinary approach (cardiothoracic, plastic and reconstructive, critical care medicine, and infectious disease) and aggressive pulmonary support, acceptable cosmetic and functional results are possible.
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PMID:Sternal resection and reconstruction. 846 35

Treatment of episodes of fever and neutropenia in pediatric hematology-oncology patients includes hospitalization and administration of intravenous antibiotics until the patient is afebrile and no longer neutropenic. The present analysis characterizes retrospectively febrile episodes in neutropenic pediatric hematology-oncology patients with regard to frequency of documented infections, organisms associated with these infections, efficacy of a standardized antibiotic regimen, and safety of early antibiotic discontinuation under defined conditions. A total of 149 pediatric febrile neutropenic episodes were identified during a 4-year period between 1990 and 1994. These occurred in 47 male and 19 female patients, of a mean age of 7.6 years (range 0.5-15). The most frequent diagnoses were leukemia (41% of patients), lymphoma (21%), rhabdomyosarcoma (7%), soft tissue sarcoma (5%), Ewing's sarcoma (5%), and osteosarcoma (4%). Infection was certain in 36% of febrile episodes, probable in 14%, and not determined in 50%. Patients with severe neutropenia (absolute neutrophil count < 100) had a slightly, although not significantly higher incidence of documented and probable infection (57%). Patients with solid tumor had documented infection in 40% of their febrile episodes, and the detection rate in the children with leukemia was 31% (P < .20) Blood cultures were positive in 21 (14%) of 149 episodes. Staphylococci (both coagulase-negative and coagulase-positive strains) and Pseudomonas were the organisms most frequently isolated (six episodes each). Mouth and throat (11), lungs (10), and skin (10) were the next most frequent sites of localized infection. Initial treatment consisted of piperacillin and amikacin or of vancomycin and amikacin when the source of fever was thought to be an infected central line catheter, with addition of amphotericin B by the seventh day of treatment when fever with neutropenia persisted or upon clinical suspicion of underlying fungal infection. There was a single fatality, of a patient with Burkitt's lymphoma. Antibiotics were discontinued when initial blood cultures had no growth after at least 48 hours and no source of infection was found, the blood count was improving, and if the patient became afebrile and clinically well. No patient needed readmission during the fortnight that followed discontinuation of antimicrobial therapy. Patients with negative blood cultures under defined conditions, as described above, could safely be discharged early, thus shortening the duration of intravenous antibiotic therapy and hospital stay.
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PMID:Fever and neutropenia in children with malignant disease. 894 Jul 33

Nineteen children were operated on between 1985 and 1994. All the patients presented a sarcoma of long bones: osteosarcoma: 12 and Ewing's sarcoma: 7. They were operated on: resection and reconstruction of the long bones with a free vascularised fibula. Pre and post-operative chemotherapy was used. The average follow-up was 3 years (between 10 years and 1 year). The mean bone defect was 20 cm (between 32 and 11 cm). Boys were more frequently encountered [12]. Average age was 9.5 years. The pathological bone was: femur: 14, tibia: 4, humerus 1. The approach needs usually two incisions for femoral bone: the internal incision allows us to prepare the recipient vessels: deep femoral vessels in 11 cases. In 18 cases, union occurred in less than 14 months. One case of pseudarthrosis occurred. Immediate follow-up was simple in 17 cases. Infection was observed in 2 cases. Secondly, the most frequent complications were: fracture of the fibula: 6 cases, vicious cal: 2 cases; delayed union: 6 cases; stiffness: 2 cases. One patient died later from pulmonary metastasis. Solid osteosynthesis of the member and of the free vascularised fibula permit to shorten these delays. Success depends on two criteria: the graft thickening of the fibula and union of the fibula at both ends. The micro vascular anastomoses must be excellent. Twelve children had bone union with only one operation. In the 6 cases of delayed union, secondary bone grafts give consolidation. The comparison of this technique with standard treatment showed an evident superiority of the free vascularised fibula transplant in extensive defects of bone. The fibula is a life bone which permits rapid union with a short hospitalization, a quick recovery and an early return to school. Free vascularised fibula permit to ameliorate the quality of survival.
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PMID:[Reconstruction of the long bones of the legs in children via free vascularized transplant of the fibula after resection for sarcoma]. 896 11

Cyclin-dependent kinase inhibitors are potent suppressors of cell growth and have been proposed as targets for gene replacement therapy in cancer. Expression of either p16INK4a or p21WAF1 protected cells from the cytotoxic effects of the topoisomerase II inhibitor, etoposide. A lower level of p53 was induced in CDK inhibitor-expressing etoposide-exposed cells suggesting that protection may be due to lower levels of DNA damage in the growth arrested cells. Exposure of human osteosarcoma cells to either p16INK4a or p21WAF1 prior to and during etoposide therapy protected cells against etoposide-induced cell death. Infection of the cells by Ad-p16INK4a or Ad-p21WAF1 following exposure to etoposide resulted in loss of the protective effect with evidence of enhanced growth inhibition. The results suggest that the schedule of administration of DNA damaging etoposide chemotherapy and cell cycle inhibitory therapy is a major determinant of the resulting cytotoxicity.
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PMID:The administration schedule of cyclin-dependent kinase inhibitor gene therapy and etoposide chemotherapy is a major determinant of cytotoxicity. 1040 29

Human T cell leukemia virus type I (HTLV-I) or its transcriptional transactivator, Tax1, was introduced into a human osteosarcoma cell line, HOS, and a Moloney murine sarcoma virus-positive HOS cell line, S+L-HOS. These HTLV-I- or Tax1-expressing cells were injected subcutaneously into nude mice to investigate the effects of HTLV-I on their tumorigenicities. HOS cells did not form any tumors even in the presence of HTLV-I or Tax1. S+L-HOS cells did form small tumors in two-thirds of nude mice. Infection of S+L-HOS cells with HTLV-I, or transduction of Tax1 into S+L-HOS cells markedly facilitated the tumor formation, and the tumor-bearing mice showed marked splenomegaly and neutrophilia. Elevated levels of granulocyte colony-stimulating factor (G-CSF) were detected in sera of these mice and also in the culture supernatants of Tax1-expressing human cells, suggesting that G-CSF in the mouse sera was produced by the human cells. In sera of some mice with splenomegaly and neutrophilia, high levels of murine granulocyte-macrophage colony-stimulating factor (mGM-CSF) were observed, suggesting that Tax1 produced by human cells induced mouse cells to produce mGM-CSF. Only S+L-HOS cell lines expressing Tax1 showed high tumorigenicity in nude mice. Thus, this system will be a useful model of tumor formation, splenomegaly and neutrophilia dependent on Tax1.
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PMID:Rapid tumor formation and development of neutrophilia and splenomegaly in nude mice transplanted with human cells expressing human T cell leukemia virus type I or Tax1. 1094 44

Expression of Fas (CD95, APO-1), a cell surface receptor capable of inducing ligand-mediated apoptosis, is involved in tissue homeostasis and elimination of targeted cells by natural killer and T cells. Corruption of this pathway, such as reduced Fas expression, can allow tumor cells to escape elimination and promote metastatic potential. In this study, the status of Fas expression has been examined in the parental SAOS human osteosarcoma cells that do not metastasize and in selected variants that cause lung metastases in 16 weeks (LM2) or 8 weeks (LM6) after i.v. injection into nude mice. Fas expression correlated with the metastatic potentials of the three cell lines. Northern and fluorescence-activated cell-sorting analyses indicated that LM6 cells expressed Fas at a lower level than seen in the parental cells. Infection of the LM6 cells with an adenoviral vector containing the murine interleukin (IL)-12 gene (AD:mIL-12) or treatment with recombinant murine IL-12 resulted in a dose-dependent up-regulation of FAS: The up-regulation of Fas by IL-12 was also demonstrated in human etoposide-resistant MDA-MB-231 breast cancer cells. [(3)H]Thymidine growth inhibition studies indicated that the cell surface Fas induced after IL-12 exposure was functional and able to mediate cell death on cross-linking with anti-FAS: We also demonstrate that this effect is independent of IFN-gamma. Whereas these cell lines are sensitive to IFN-gamma, incubation with IFN-gamma does not increase susceptibility to Fas-mediated cell death, nor do these cells produce IFN-gamma with or without IL-12 treatment. We hypothesize that expression of Fas may play a role in the elimination of metastatic tumor cells in the lung, an organ in which Fas ligand is expressed. The antitumor activity of IL-12 may be secondary in part to its ability to up-regulate Fas expression on tumor cells, which subsequently increases immune-mediated destruction of osteosarcoma cells.
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PMID:Interleukin (IL)-12 and IL-12 gene transfer up-regulate Fas expression in human osteosarcoma and breast cancer cells. 1135 27


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