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)

P-glycoprotein is an adenosine triphosphate-dependent drug-efflux pump that extrudes drugs from cells and causes drug-resistance. P-glycoprotein is believed to mediate drug-resistance in a wide variety of tumors. In this study, we developed two P-glycoprotein-positive, murine osteosarcoma cell lines that were resistant to Adriamycin (doxorubicin) (MOS/ADR1 and MOS/ADR2). We created the cell lines by short-term pulse exposures of the parent cell line to Adriamycin followed by single-cell cloning. The MOS/ADR1 and MOS/ADR2 cells were sevenfold and eighteenfold more resistant to Adriamycin than the cells from the parent line. Expression of P-glycoprotein, as examined with an immunofluorescence method, was detected in most of the MOS/ADR1 and MOS/ADR2 cells but not in the parent cells. After the cells had been incubated with Adriamycin for one hour, there was less accumulation of the drug in the resistant cell lines than in the parent cell line. The reduced accumulation was due to the increased efflux of Adriamycin. The Adriamycin-resistant cell lines demonstrated greater alkaline phosphatase activity than the parent cell line and produced more differentiated osteoblastic sarcomas in mice. Dose survival studies with use of a tetrazolium colorimetric assay showed that the MOS/ADR1 cells were cross-resistant to vincristine, vinblastine, etoposide, bleomycin, mitomycin C, and actinomycin D but not to dacarbazine, cisplatin, carboplatin, cytosine arabinoside, carmustine, cyclophosphamide, ifosfamide, methotrexate, and 5-fluorouracil. Although the MOS/ADR2 cells exhibited a similar spectrum of cross-resistance, they were more resistant than the MOS/ADR1 cells. We also tested the effect of three different resistance-modifying agents on the reversal of resistance to Adriamycin. We found that verapamil and trifluoperazine substantially reversed resistance to Adriamycin in the P-glycoprotein positive cell lines, whereas cyclosporin A was relatively ineffective. Because these cell lines retain the histological and biochemical features of bone-producing sarcomas and display the multidrug-resistant phenotype, they may be useful models for additional investigations of drug resistance in osteosarcoma.
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PMID:Experimental models for the study of drug resistance in osteosarcoma: P-glycoprotein-positive, murine osteosarcoma cell lines. 861 43

Intra-arterial (IA) and intravenous (IV) cisplatinum (CDP) were studied in a multiagent regimen of neoadjuvant chemotherapy for osteosarcoma of the extremities. Preoperatively two cycles of high-dose methotrexate (HDMTX) were administered, followed 5 days later by CDP and Adriamycin (ADM). MTX and ADM were administered IV, and CDP was delivered IA or IV. Postoperatively, good responders received 3 more cycles of the same drugs, while poor responders had a longer chemotherapy including ifosfamide. The rate of good histological response to chemotherapy was significantly higher in patients treated intraarterially (78% vs 46%: P < .004), while no significant differences in terms of disease-free survival were observed between patients who received CDP IA and patients who received CDP IV (55% vs 51%). In the IA group, however, there was only one local recurrence vs 5 in the IV group. The IA infusion of CDP is more active on the primary tumor than the IV infusion.
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PMID:Intra-arterial versus intravenous cisplatinum (in addition to systemic Adriamycin and high dose methotrexate) in the neoadjuvant treatment of osteosarcoma of the extremities. results of a randomized study. 883 14

The authors investigated the influence of methotrexate (MTX) serum concentration on (histologically evaluated) tumor necrosis, induced by a primary multiagent chemotherapy, including MTX, for osteosarcoma. MTX serum peaks in 151 patients, preoperatively treated with MTX (8-12g/m2), cisplatin (120mg/m2) and Adriamycin (60mg/m2), were analyzed. Significantly (p < 0.01) higher serum MTX mean peaks were observed in patients with complete tumor necrosis (MTX 773.8 mumol/l) compared to patients with 90-99% tumor necrosis (639.8 mumol/l), 50-89% tumor necrosis (649.1 mumol/l) or less than 50% tumor necrosis (610 mumol/l). Complete tumor necrosis was observed in 9% of patients with MTX peaks of less than 600 mumol/l, in 27% of patients with serum MTX peaks between 600 and 699 mumol/l and in 37% of those with MTX peaks ranging from 700 to 799 mumol/l. Higher MTX peaks (800-899, 900-999, > 1000 mumol/l) were not associated with a further increase of cases with complete tumor necrosis. 40% of patients with an MTX peak greater than 700 mumol/l had complete tumor necrosis, compared to 15.5% of patients who did not reach this value (p < 0.002). At a multivariant analysis including age, sex, tumor site and volume, pretreatment serum alkaline phosphatase and lactic dehydrogenase levels, MTX peaks of 700 mumol/l and, less significantly, the histologic type (telangiectatic osteosarcoma), were independent factors influencing tumor necrosis. The authors conclude that MTX serum peaks significantly influence chemotherapy-induced tumor necrosis in osteosarcoma. In a primary treatment consisting of cisplatin, Adriamycin and MTX, complete tumor necrosis can be obtained in 40% of patients with MTX peak concentrations > or = 700 mumol/l.
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PMID:Methotrexate serum concentration and histological response to multiagent primary chemotherapy for osteosarcoma of the limbs. 898 Nov 89

This prospective study was designed to test the activity of an ifosfamide-etoposide (VP-16) regimen on poor-risk, nonmetastatic, osteogenic sarcoma. A total of 13 patients with nonmetastatic osteogenic sarcoma with a poor histologic response to primary high-dose methotrexate-doxorubicin (Adriamycin)-cisplatinum chemotherapy received a total of six 5-day courses of ifosfamide (1,800 mg/m2) and etoposide (100 mg/m2) at three weekly intervals. The protocol was well tolerated, with only one case of transient renal failure. At present, eight patients (62%) have been in sustained complete remission with no evidence of recurrent disease for a mean follow-up of 3.4 years (range, 1.5-7.0 years). One patient is alive with lung metastases, and four have died of progressive disease. This prospective, albeit small, study confirms the efficacy of an ifosfamide-VP-16-based regimen in poor-risk, extremity, nonmetastatic osteogenic sarcoma. The demonstrated activity should spark large trials of ifosfamide-containing regimens in osteogenic sarcoma.
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PMID:Postsurgical etoposide-ifosfamide regimen in poor-risk nonmetastatic osteogenic sarcoma. 949 63

Bone only metastasis in patients with estrogen receptor (ER) positive breast cancer reported to have favorable response to chemotherapy, favorable prognosis, and an "indolent" course. Therefore, we assessed the ability of MG-63 osteoblast-like human osteosarcoma cells (MG-63 cells) and MG-63 conditioned media (CM) to influence adriamycin-cytotoxicity of ER-positive MCF-7 human breast cancer cells. Estradiol (E2; 100 nM) increased the distribution at S and G2/M phases in the cell cycle and stimulated the growth of MCF-7 cells. Adriamycin (100 nM) inhibited the growth and arrested the MCF-7 cells supplemented with or without 100 nM of estradiol [(-E2) and (+E2) MCF-7 cultures] at G2/M phase in the cell cycle. In addition, adriamycin (100 nM) increased the distribution at G1/G0 phase in the cell cycle of (+E2) MCF-7 cultures. Adriamycin (100 nM and 10 microM) did not induce apoptosis of MCF-7 cells as assessed by flow cytometry and analysis of DNA fragmentation on simple agarose gel. Exogenous insulin-like growth factor I (IGF I) stimulated while transforming growth factor beta 1 (TGF beta 1) and MG-63 CM inhibited the growth of MCF-7 cells. Furthermore, MG-63 CM and TGF beta 1 enhanced while exogenous IGF I reversed adriamycin (100 nM)-cytostasis of MCF-7 cells. These data suggested that osteoblastic CM contained growth factors, such as TGF beta 1 capable of enhancing adriamycin-cytostasis, in vitro. Conceivably, these osteoblast-derived "enhancers" of chemotherapy-cytostasis can explain the favorable prognosis and "indolent" course of ER-positive breast cancer patients with bone only metastasis.
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PMID:Osteoblast-derived growth factors enhance adriamycin-cytostasis of MCF-7 human breast cancer cells. 989 70

Neoadjuvant chemotherapy plays a significant role in improving the prognosis of malignant bone tumors such as osteosarcoma and Ewing's sarcoma. Doxorubicin, cisplatin and high-dose methotrexate are key drugs in the chemotherapy for osteosarcoma. Intraarterial administration of the drugs is very effective in local control, so that wide resection of the tumor may be performed safely. The efficacy of preoperative chemotherapy is evaluated by the histological necrosis rate of the resected tumor after which postoperative drugs will be chosen. Limb salvage is becoming more and more common, and an excellent limb can be reconstructed using an artificial joint. In soft tissue sarcomas, brachytherapy can make the surgical resection margin narrower, resulting in good function of the extremities. Fragility of bone caused by metastatic bone diseases is reversed by surgical intervention.
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PMID:[Recent advances in management of musculoskeletal tumors]. 1041 Jun 73

The purpose of these studies was to determine whether interferon-alpha (IFN-alpha) could enhance the sensitivity of human osteosarcoma cells to the cytotoxic actions of etoposide (VP-16). Cytostasis was determined using a [3H]thymidine incorporation assay, whereas cytotoxicity was quantified by a colony-formation assay. Low concentrations (0.1-5 U/ml) of IFN-alpha enhanced the cytostatic activity of VP-16 against MG-63, SAOS-2, and TE-85 osteosarcoma cells. The cytostatic activity of 1 microM VP-16 rose from 11% to 64%, 9% to 31%, and 10% to 71%, respectively, in the three cell lines when IFN-alpha was present. Survival fraction was also decreased when the osteosarcoma cells were treated with VP-16 + IFN-alpha as compared to either agent alone. The interaction between these two agents was determined to be synergistic rather than additive by interaction index analysis. Similar effects on cytostasis and cytotoxicity were observed when IFN-alpha was combined with Adriamycin but not cisplatin, actinomycin D, vinblastine, or amsacrine. VP-16 uptake was enhanced 12-fold in the presence of IFN-alpha, but this did not appear to translate into an increase in topoisomerase-II (topo-II)-DNA complex formation as quantified by the sodium dodecyl sulfate-KCl precipitation assay. We also could not detect alterations in topo-II expression, topo-II protein production, or cell cycle kinetics that have been shown to correlate with increased VP-16 cell sensitivity. Therefore, at this time the mechanism of enhanced cell sensitivity to the combination treatment remains unclear.
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PMID:Interferon-alpha enhances the sensitivity of human osteosarcoma cells to etoposide. 1043 62

One of the major factors for efficacy of a chemotherapeutic drug is its activity to induce apoptosis of tumor cells. Doxorubicin and daunorubicin, radiomimetic anthracycline-group drugs, have been used for chemotherapy for about 30 years. Here we established the colorectal tumor and osteosarcoma cells in which Bax expression can be induced by the treatment of isopropyl-beta-D-thiogalactopyranoside, and examined the effect of the Bax overexpression on the cell death caused by these drugs. While the Bax overexpression neither affected growth nor morphology of the undamaged cells, it enhanced the cell death caused by these drugs. Increase in cellular nucleus fragmentation and DNA ladder formation indicates that the Bax-enhanced cell death is due to enhanced apoptosis of the drug-treated cells. The enhanced cell death was not observed when the cells were irradiated with X-ray or treated with other chemotherapeutic agents we examined. These results indicate that Bax may have a specific role to enhance the efficacy of chemotherapy with anthracycline-group agents.
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PMID:Apoptosis of human tumor cells by chemotherapeutic anthracyclines is enhanced by Bax overexpression. 1064 88

After pulsed exposure of Dunn osteosarcoma cells (nonresistant cells) to Adriamycin (ADR) at increasing concentrations and single-cell cloning of surviving cells, ADR-resistant cells were obtained. These resistant cells expressed P-glycoprotein and had resistance more than 10 times that of their nonresistant parent cells. Compared to the nonresistant cells not exposed to pulsing electromagnetic fields (PEMF) in ADR-free medium, their growth rates at ADR concentrations of 0.01 and 0.02 micrograms/ml, which were below IC50, were 83.0% and 61.8%, respectively. On the other hand, in the nonresistant cells exposed to PEMF (repetition frequency, 10 Hz; rise time, 25 microsec, peak magnetic field intensity, 0.4-0.8 mT), the growth rate was 111.9% in ADR-free medium, 95.5% at an ADR concentration of 0.01 micrograms/ml, and 92.2% at an ADR concentration of 0.02 micrograms/ml. This promotion of growth by PEMF is considered to be a result of mobilization of cells in the non-proliferative period of the cell cycle due to exposure to PEMF. However, at ADR concentrations above the IC50, the growth rate tended to decrease in the cells not exposed to PEMF. This may be caused by an increase in cells sensitive to ADR resulting from mobilization of cells in the non-proliferative period to the cell cycle. The growth rate in the resistant cells exposed to PEMF was significantly lower than that in the non-exposed resistant cells at all ADR concentrations, including ADR-free culture (P</=0.0114). Therefore, this study suggests that PEMF promotes the growth of undifferentiated cells but progressively suppresses the growth of more differentiated cells, i.e., PEMF controls cell growth depending on the degree of cell differentiation. This study also shows the potentiality of PEMF as an adjunctive treatment method for malignant tumors.
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PMID:Effects of PEMF on a murine osteosarcoma cell line: drug-resistant (P-glycoprotein-positive) and non-resistant cells. 1065 22

Morbidity resulting from the toxicity of chemotherapeutic drugs suggests that novel approaches are worthy of investigation. Development of the use of low intensity magnetic fields as an adjuvant to current treatment regimens to prevent metastatic disease may prove to be efficacious. Using a cell culture model, we have developed a magnetic field (MF) treatment that offers the possibility of lowering the therapeutic dose of these drugs and thereby reducing morbidity. Our studies have found that a low intensity (approximately 2 gauss) MF signal and a relatively low dose (0.1 microg/ml) of Adriamycin (ADR) inhibited proliferation of human osteosarcoma cells by 82%, whereas the MF and ADR acting individually caused only 19% and 44% inhibition, respectively.
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PMID:Magnetic field induced inhibition of human osteosarcoma cells treated with adriamycin. 1073 5


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