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)

Ifosfamide, Carboplatin and Etoposide (ICE) therapy was used to treat 4 patients, 2 with refractory osteosarcoma, and one each with relapsed brain tumor and newly diagnosed brain tumor. ICE therapy was administered in doses of Ifosfamide 1,800 mg/m2 x 5, Carboplatin 400 mg/m2 x 2 and Etoposide 100 mg/m2 x 5. A total of 30 courses were administered. Two cases of osteosarcoma had a stable disease (range, 3-9 months) and 2 cases of brain tumor had a complete response by magnetic resonance imaging. Moderate or severe toxicity evaluated on a per course basis included: neutropenia 83%, thrombocytopenia 93%, fever 30%, hepatotoxicity 3%, and hemorrhagic cystitis 3%. The median time to hematologic recovery was 20 days. ICE therapy is highly effective for the treatment of refractory or recurrent solid tumors with acceptable toxicity.
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PMID:[Pilot study of relapsed osteosarcoma and brain tumor with ifosfamide, carboplatin and etoposide (ICE therapy)]. 949 32

Apo2L/TRAIL is a member of the tumor necrosis factor (TNF) family of cytokines that induces death of cancer cells but not normal cells. Its potent apoptotic activity is mediated through its cell surface death domain-containing receptors, DR4 and DR5. Apo2L/TRAIL interacts also with 3 "decoy" receptors that do not induce apoptosis, DcR1, DcR2, which lack functional death domains, and osteoprotegerin (OPG). The aim of our study was to investigate the cytotoxic activity of Apo2L/TRAIL on established osteogenic sarcoma cell lines (BTK-143, HOS, MG-63, SJSA-1, G-292 and SAOS2) and in primary cultures of normal human bone (NHB) cells. When used alone, Apo2L/TRAIL at 100 ng/ml for 24 hr induced greater than 80% cell death in only 1 (BTK-143) of the 6 osteogenic sarcoma cell lines. In contrast, Apo2L/TRAIL-resistant cells were susceptible to Apo2L/TRAIL-mediated apoptosis in the presence of the anticancer drugs, Doxorubicin (DOX), Cisplatin (CDDP) and Etoposide (ETP) but not Methotrexate (MTX) or Cyclophosphamide (CPM). Importantly, neither Apo2L/TRAIL alone nor in combination with any of these drugs affected primary normal human bone cells under equivalent conditions. Apo2L/TRAIL-induced apoptosis, and its augmentation by chemotherapy in the resistant cell lines was mediated through caspase-8 and caspase-3 activation. Furthermore, Apo2L/TRAIL-induced apoptosis and its augmentation by chemotherapy was effectively inhibited by caspase-8 zIETD-fmk and caspase-3 zDEVD-fmk protease inhibitors and by the pan-caspase inhibitor zVAD-fmk. The pattern of basal Apo2L/TRAIL receptor mRNA expression, or expression of the intracellular caspase inhibitor FLICE-inhibitory protein, FLIP, could not be readily correlated with resistance or sensitivity to Apo2L/TRAIL-induced apoptosis. However, the augmentation of Apo2L/TRAIL effects by chemotherapy was associated with drug-induced up-regulation of death receptors DR4 and DR5 mRNA and protein. No obvious correlation was seen between the expression of OPG mRNA or protein and susceptibility of cells to Apo2L/TRAIL-induced apoptosis. Stable over-expression of a dominant negative form of the Fas-associated death domain protein (FADD) in the Apo2L/TRAIL-sensitive BTK-143 cells completely inhibited Apo2L/TRAIL-induced cell death. Our results indicate that chemotherapy and Apo2L/TRAIL act synergistically to kill cancer cells but not normal bone-derived osteoblast-like cells, which has implications for future therapy of osteosarcoma.
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PMID:Chemotherapeutic agents sensitize osteogenic sarcoma cells, but not normal human bone cells, to Apo2L/TRAIL-induced apoptosis. 1199 38

Interferonalpha (IFNalpha) induces cell cycle arrest and triggers apoptosis and chemosensitivity. But the mechanism of IFNalpha in regulating chemosensitivity has not been fully understood. To study whether IFNalpha affected chemosensitivity of osteosarcoma cells, we treated p53-wild U2OS cells and p53-mutant MG63 cells with IFNalpha and etoposide, alone or in combination, and then examined growth inhibition, cell cycle arrest and apoptosis. IFNalpha enhanced etoposide-induced growth inhibition and apoptosis in p53-wild U2OS cells but not p53-mutant MG63 cells in a dose- and time-dependent manner. Etoposide-induced G2/M phase arrest was also enhanced by IFNalpha. The enhanced apoptosis was associated with the accumulation of transcriptionally active p53 accompanied with increased Bax and Mdm2, as well as decreased Bcl-2. IFNalpha also activated caspases-3, -8 and -9 protein kinases and PARP cleavage in response to etoposide in U2OS cells. Moreover, the combination-induced cytotoxicity and PARP cleavage were significantly reduced by caspase pan inhibitor and p53 siRNA. Thus we conclude that IFNalpha enhances etoposide-induced apoptosis in human osteosarcoma U2OS cells by a p53-dependent and caspase-activation pathway. The proper combination of IFNalpha and conventional chemotherapeutic agents may be a rational strategy for the treatment of human osteosarcoma with functional p53.
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PMID:Interferonalpha enhances etoposide-induced apoptosis in human osteosarcoma U2OS cells by a p53-dependent pathway. 1819 51

In the current work, we compared the ability of 17beta-estradiol (E2) and the selective estrogen receptor modulators (SERMs), tamoxifen (Tam), raloxifene (Ral) and ospemifene (Osp) to promote the survival of osteoblast-derived cells against etoposide-induced apoptosis. In order to compare the roles of the two estrogen receptor (ER) isotypes, we created a U2OS human osteosarcoma cell line stably expressing either ERalpha (ERalpha) or ERbeta (ERbeta). Transfection with either of the ERs was able to render the U2OS cells sensitive to E2. We show that E2 opposed etoposide-induced apoptosis and that the effect was mediated via both ER isotypes. The ER isotype selective agonists propyl-pyrazole-triol (PPT) and diarylpropionitrile (DPN) had the same effect in U2OS/ERalpha and U2OS/ERbeta cells, respectively. Osp also opposed apoptosis at least in U2OS/ERalpha cells. Tam and Ral were not able to protect against etoposide-induced cell death. In order to evaluate the protective effects of E2 and Osp upon etoposide challenge, we studied the expression of two E2-regulated, osteoblast-produced cytokines, IL-6 and OPG in E2 and SERM-treated U2OS/ERalpha and U2OS/ERbeta cells. Etoposide strongly increased expression of IL-6 and decreased that of OPG. E2 opposed IL-6 increase only in U2OS/ERalpha cells and OPG decrease primarily in ERbeta cells. Osp opposed the effect of etoposide on OPG primarily in U2OS/ERbeta cells but interestingly, it had little effect on IL-6 expression. E2, PPT, DNP and Osp also inhibited etoposide-induced death and cytokine changes in SAOS-2 osteosarcoma cells expressing endogenous ERalpha and ERbeta. Collectively, our results suggest that the osteoblast protective anti-apoptotic effects of E2 are mediated by both ERalpha and ERbeta but those of Osp primarily by ERalpha. In addition, E2 and Osp opposed the etoposide-induced increase of IL-6 and decrease of OPG which changes would increase osteoclastic activity. These anti-resorptive effects of E2 and Osp upon etoposide challenge differed from each other and they seemed to be differentially mediated in ERalpha and ERbeta expressing osteoblast-derived U2OS cells.
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PMID:Estrogen and the selective estrogen receptor modulator (SERM) protection against cell death in estrogen receptor alpha and beta expressing U2OS cells. 1845 92

Background. Osteosarcoma is a highly malignant bone tumour. After the second relapse, the 12-month postrelapse disease-free survival (PRDFS) rate decreases below 20%. Oral Etoposide is often used in clinical practice after surgery as an "adjuvant" outside any protocol and with only limited evidence of improved survival. Viscum album fermentatum Pini (Viscum) is an extract of mistletoe plants grown on pine trees for subcutaneous (sc) injection with immunomodulatory activity. Methods. Encouraged by preliminary findings, we conducted a study where osteosarcoma patients free from disease after second metastatic relapse were randomly assigned to Viscum sc or Oral Etoposide. Our goal was to compare 12-month PRDFS rates with an equivalent historical control group. Results. Twenty patients have been enrolled, with a median age of 34 years (range 11-65) and a median follow-up time of 38.5 months (3-73). The median PRDSF is currently 4 months (1-47) in the Etoposide and 39 months (2-73) in the Viscum group. Patients getting Viscum reported a higher quality of life due to lower toxicity. Conclusion. Viscum shows promise as adjuvant treatment in prolonging PRDFS after second relapse in osteosarcoma patients. A larger study is required to conclusively determine efficacy and immunomodulatory mechanisms of Viscum therapy in osteosarcoma patients.
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PMID:A Randomized Study on Postrelapse Disease-Free Survival with Adjuvant Mistletoe versus Oral Etoposide in Osteosarcoma Patients. 2480 44

Osteosarcoma (OS) is the most common primary malignant bone tumor and prevalently occurs in the second decade of life. Etoposide, a chemotherapeutic agent used in combined treatments of recurrent human OS, belongs to the topoisomerase inhibitor family and causes DNA breakage. In this study we evaluated the cascade of events determined by etoposide-induced DNA damage in OS cell lines with different p53 status focusing on methylation status and expression of miR-34a that modulate tumor cell growth and cell cycle progression. Wild-type p53 U2-OS cells and U2-OS cells expressing dominant-negative form of p53 (U2- OS175) were more sensitive to etoposide than p53-deficient MG63 and Saos-2 cells, showing increased levels of unmethylated miR-34a, reduced expression of CDK4 and cell cycle arrest in G1 phase. In contrast, MG63 and Saos-2 cell lines presented aberrant methylation of miR-34a promoter gene with no miR-34a induction after etoposide treatment, underlining the close connection between p53 expression and miR-34a methylation status. Consistently, in p53siRNA transfected U2-OS cells we observed loss of miR-34a induction after etoposide exposure associated with a partial gain of gene methylation and cell cycle progress towards G2/M phase. Our results suggest that the open and unmethylated conformation of the miR-34a gene may be regulated by p53 able to bind the gene promoter. In conclusion, cell response to etoposide-induced DNA damage was not compromised in cells with dominant-negative p53 expression.
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PMID:p53-dependent activation of microRNA-34a in response to etoposide-induced DNA damage in osteosarcoma cell lines not impaired by dominant negative p53 expression. 2549 93

Osteosarcoma (OSA) is the most common primary bone tumour in dogs. The poor survival rate in dogs with OSA highlights the need for new therapeutic approaches. This study evaluated the cytotoxic effects of etoposide, alone and in combination with piroxicam, on canine OSA cell cultures. Etoposide alone significantly suppressed cell growth and viability, whereas etoposide in combination with piroxicam exhibited concentration dependent cytotoxicity. The anti-proliferative effect was a result of inactivity of the Cdc2-cyclin B1 complex, which correlated with an increase in the G2/M fraction. This subsequently activated the apoptosis cascade, as indicated by elevated apoptosis levels and up-regulation of poly (ADP-ribose) polymerase proteolytic cleavage. Down-regulation of survivin expression induced by the combination treatment may have contributed to the enhanced cytotoxicity. The results of this study suggest that further investigation of etoposide and piroxicam as a therapeutic combination for canine OSA is warranted.
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PMID:Effects of etoposide alone and in combination with piroxicam on canine osteosarcoma cell lines. 2793 9

Osteosarcoma (OSA) in dogs is locally invasive and highly malignant. Distant metastasis is the most common cause of death. To date, the survival rate in dogs with OSA remains poor. The cytotoxic effects of etoposide against canine OSA cell lines, either alone or in combination with piroxicam, have been previously demonstrated in vitro. The aim of this study was to evaluate the anti-tumour effect of etoposide alone and in combination with piroxicam on canine OSA using murine models. Etoposide single agent treatment significantly delayed tumour progression with a marked reduction in Ki-67 immunoreactivity in tumour tissue. Concomitant treatment with piroxicam did not enhance the anti-tumour efficacy of etoposide. Etoposide single agent treatment and combination treatment with piroxicam down-regulated survivin expression, but was not followed by increased apoptotic activity. These findings indicate that etoposide might be a promising novel therapeutic for canine OSA. Further investigations into its potential for clinical application in veterinary oncology are warranted.
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PMID:Anti-tumour efficacy of etoposide alone and in combination with piroxicam against canine osteosarcoma in a xenograft model. 2895 80

High-grade conventional osteosarcoma of the mandible is a rare entity that can manifest as a rapidly growing mass. The authors report the case of a young adult patient with right mandible pain and swelling and a history of humeral osteosarcoma treated over 1 decade earlier. Computed tomography and magnetic resonance imaging showed a mass arising from the right mandible that progressed despite induction chemotherapy and the patient underwent surgery. Histopathology revealed the presence of malignant osteoblasts and osteoid, which led to the diagnosis of high-grade conventional osteosarcoma. There were also regional lymph node metastases. Genetic testing revealed a p53 germline mutation. The presence of mandibular osteosarcoma in a young patient should raise the suspicion of an underlying p53 germline mutation. Ultimately, the recurrent tumor regressed with Etoposide and Ifosfamide.
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PMID:High-Grade Conventional Osteosarcoma of the Mandible Associated With P53 Germline Mutation. 2942 Mar 87