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

The human osteosarcoma cell line (OST-1-PF) can grow in protein-free Coon's modified Ham's F12 medium. Growth of the cells in protein-free medium was partially density-dependent and partially depressed by medium change. An extract and conditioned medium of OST-1-PF cells contained high mitogenic activity for BALB/c3T3 cells. The growth factor in the cells was purified and identified as a basic fibroblast growth factor (bFGF)--like factor on the basis of its elution profile on heparin-affinity chromatography and the result of immunoblotting. An unidentified factor in a conditioned medium eliciting most of the DNA synthesis-stimulating activity showed a weak affinity for heparin. Various additions, including serum and growth factors, stimulated the growth of OST-1-PF cells in protein-free medium. Of these factors, epidermal growth factor (EGF), transforming growth factor-alpha (TGF-alpha), acidic fibroblast growth factor (aFGF) and bFGF were the most potent mitogens. High-affinity receptors of EGF and FGF were found on the surface of these cells. These results indicate that autonomous growth of OST-1-PF cells in protein-free medium is mainly controlled by an intracellular mechanism.
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PMID:Roles of various growth factors in growth of human osteosarcoma cells which can grow in protein-free medium. 158 71

We investigated the differentiation-inducing effects of dibutyryl cyclic AMP (dBc AMP) on several cultured osteosarcoma cell lines (DUNN, MOLONEY, OST, FBJ). 1. Cell growth rates of all the osteosarcoma cell lines were reduced by 3mM dBc AMP. 2. Both alkaline phosphatase activity and 45Ca2(+)-uptake were promoted by 3mM dBc AMP. 3. There was, in each cell line except for the OST cells, a marked enlargement of the cell processes under the light microscopic observation. At the electron microscopic level, there were also many findings indicating an increase in cell functions. These results suggest that the differentiation may be induced by cAMP in osteosarcoma cells, and that the differentiation therapy by cAMP-related drugs is promising for a clinical application.
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PMID:[Experimental study on maturational therapy of osteosarcoma cell]. 216 18

Recently, it has been revealed that anticancer effects are increased by the inhibition of DNA repair of cancer cells. Methylxanthine is the drug which block DNA repair. In this study we discussed the combined effects of CDDP and caffeine or pentoxifylline using human osteosarcoma cells (OST strain). When 2 mM caffeine was added before 1 hr exposure of CDDP or caffeine and CDDP was added simultaneously for 1 hr, no synergistic effect was shown. On the other hand, marked synergistic growth inhibition was observed when caffeine or pentoxifylline was added continuously after 1 hr exposure of CDDP. The addition of caffeine from 24 hr to 48 hr after 1 hr exposure of CDDP also showed synergistic effects as the doubling time of OST cells was about 30 hrs. Further more we treated three patients with advanced osteosarcomas by the combination of CDDP, ADM, and caffeine (p.o.) or that of CDDP and caffeine. A nine-year-old boy with multicentric osteosarcoma treated by the combination of CDDP, ADM, and caffeine showed partial response, and caffeine did not increase the side effects of anticancer agents. Hence the study on overcoming drug resistance by the inhibition of DNA repair will be promising.
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PMID:[DNA repair and drug resistance: enhancement of the effects of anticancer agents by DNA repair inhibitors]. 270 88

A nontoxic dose of caffeine enhanced the cytotoxicity of cisplatin in human osteosarcoma cells (OST strain). Synergistic cytotoxicity was seen in vitro in OST cells when 2 mmol caffeine was added to a nontoxic dose of cisplatin (2 micrograms/ml). Caffeine reduced S-phase, G2/M-phase, and S-and-G2/M-phase accumulation by cisplatin on the DNA histogram, and nuclear fragmentation of tumor cells was frequently observed. Flow cytometric analysis appeared to be useful in assessing the efficacy of the combination of cisplatin and caffeine. The antitumor effect of the combination of cisplatin and caffeine was examined in OST transplanted to BALB/C athymic mice. Regression of the tumor was observed when cisplatin was given at a dose of 10 mg/kg. When 4 mg of caffeine was given once a day for three days after the administration of cisplatin, marked regression of the tumor was observed in groups treated with 5 or 10 mg/kg of cisplatin, without significant weight loss. These results indicate that caffeine enhances the antitumor effect of cisplatin on transplanted osteosarcoma in BALB/C athymic mice.
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PMID:Enhancement of cytocidal and antitumor effect of cisplatin by caffeine in human osteosarcoma. 272 Jul 27

We studied hyperthermia for malignant tumors of the extremities, and obtained the following findings. In osteosarcoma cultured cells from OST (Human) and Dunn (Mouse), proliferation was clearly inhibited on being heated to 42 approximately 43 degrees C. On heat-treating the femurs of pigs, a rise in temperature to 42.5 degrees C or above was observed so that an antitumor effect could be anticipated. Moreover, no abnormal rise in temperature in the tissues surrounding the bone and light microscopy revealed no particular abnormalities. Clinically, a rise in temperature above 42.5 degrees C was observed in the majority of the malignant bone tumors (4 cases of osteosarcoma and 1 case of chordoma) and soft tissue tumors (1 case of epithelioid sarcoma, malignant fibrous histiocytoma, rhabdomyosarcoma, malignant melanoma and osteosarcoma) of which 2 cases were metastatic tumors. Before administration, 7 patients complained of pain, 4 of whom (57%) experienced an alleviation following treatment. Also in 5 (50%) out of 10 cases a shrinking of the tumor was observed and especially, in the case of soft tissue tumors a tendency towards a softening of tumor texture was seen.
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PMID:[Hyperthermia in malignant tumors of the extremities--experimental heating by a radiofrequency applicator and its clinical significance]. 273 74

A study on the effect of anti-tumor agents combined with caffeine on sarcoma cells was carried out by clonogenic assay. The materials used were an established line of human osteosarcoma cells (OST strain) and twelve surgically resected or biopsied specimens. Caffeine showed a marked synergistic effect on sarcoma cells with the DNA-damaging agents, ADR, CDDP, CPM and MMC in terms of colony inhibition. In particular, 0.2 micrograms/ml CDDP with 2 mM caffeine showed a considerable synergistic effect on human sarcoma cells. Among the 12 cases, more than 50% colony inhibition was observed in 7 cases which were treated with this combination of CDDP with caffeine. Furthermore, a combination of 0.02 micrograms/ml CDDP (1/100 of peak plasma concentration) with 2 mM caffeine also showed more than 50% colony inhibition. Therefore, we assumed that caffeine was able to reduce the necessary dose of anti-tumor agent in some way. We stress that caffeine seems to be a very useful synergistic drug for causing lethality in sarcoma cells in combination with various DNA-damaging agents which are not effective on sarcoma cells.
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PMID:[A study of the effect of anti-tumor agents combined with caffeine on established lines of human osteosarcoma cells and primary cultured human sarcoma cells by clonogenic assay]. 347 41

It has been previously reported that several human cancer cell lines possess specific receptors for 1,25-dihydroxyvitamin D3. In the present study, the concentration of the 1 alpha,25 dihydroxyvitamin D3 receptors has been determined in four human osteosarcoma cell lines--MG63, OST, MNNG-HOS, and KHOS-NP, and we report the effect of 1 alpha, 25 dihydroxyvitamin D3 on these cells. The concentration of 1 alpha, 25 dihydroxyvitamin D3 receptors in MG63, OST, MNNG-HOS and KHOS-NP was 31.1, 12.1, 5.9 and 3.0 fmol/mg of cytosol protein, respectively. These cell lines were classified into two groups according to the concentration of the receptors. The two receptor-rich cell lines were MG63 and OST, and the receptor-poor cell lines were MNNG-HOS and KHOS-NP. In a colony-forming assay, 1 alpha, 25 dihydroxyvitamin D3 (10(-8)M, 10(-9)M) was found to significantly suppress the growth of the receptor-rich cell lines (p < 0.01), but did not suppress that of the receptor-poor cell lines. In an antitumor assay, athymic mice received a transplantation of tumor cells and were treated with 2.5 nmol/kg of 1 alpha hydroxyvitamin D3. Then the relative mean weight of the tumor was measured (MG63 was, however, not transplantable into athymic mice.) As a result, 1 alpha hydroxyvitamin D3 was found to have significantly suppressed the relative mean tumor weight of OST and MNNG-HOS compared with a control group (p < 0.05), but did not suppress that of KHOS-NP. Histologically, 1 alpha hydroxyvitamin D3 induced marked chondrogenetic differentiation in OST alone.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Correlation between the concentration of 1,25 alpha dihydroxyvitamin D3 receptors and growth inhibition, and differentiation of human osteosarcoma cells induced by vitamin D3]. 778 56

The differentiating and antitumor activities of 1 alpha,25-dihydroxyvitamin D3 (1 alpha,25(OH)2D3) in vitro and 1 alpha-hydroxyvitamin D3 (1 alpha(OH)D3) in vivo were studied with a human osteosarcoma cell line (OST strain). Anti-tumor activity was estimated with the use of 3-(4,5-dimethylthiazol)-2, 5-diphenyltetrazolium bromide (MTT) assay, colony-forming assay, and athymic mouse assay. The intracellular alkaline phosphatase (ALP) activity of tumor cells and production of bone Gla protein (BGP) in culture media were measured to mark osteoblastic differentiation. In addition, the combination of 1 alpha,25(OH)2D3 and cis-dichlorodiammineplatinum(II) (CDDP) was tested by the colony-forming assay and the measurement of ALP activity and BGP production for differentiating and antitumor effects. The assays revealed that 1 alpha,25(OH)2D3 exerted a dose-related, growth-inhibitory influence. In the colony-forming assay, the 1 alpha,25(OH)2D3-treated colonies were smaller than the untreated colonies. The ALP activity and the BGP production also increased in relation to dose. In the assay in athymic mice, the relative weight of tumors treated with 1 alpha(OH)D3 at 2.5 nmol/kg was significantly smaller than that of the controls, and no side effects were observed in the 1 alpha(OH)D3-treated mice. Marked tumor chondrogenesis was observed in human osteosarcoma treated with 1 alpha(OH)D3 in athymic mice. The combination of 1 alpha,25(OH)2D3 at 10(-8) M and CDDP at 2 micrograms/ml significantly enhanced both the differentiation and the growth inhibition in vitro. Our study apparently is the first demonstration that vitamin D3 metabolites have an antitumor and differentiating effect on human osteosarcoma cells in vitro and in athymic mice.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Differentiating and antitumor activities of 1 alpha,25-dihydroxyvitamin D3 in vitro and 1 alpha-hydroxyvitamin D3 in vivo on human osteosarcoma. 842 14

Two human osteosarcoma cell lines, Hu09 and OST, were suspended in Matrigel (Becton Dickinson Labware, Bedford, Massachusetts) and implanted subcutaneously in the backs of nude mice. To study phenotypic changes of tumor cells and host cells, expression of mRNA for osteopontin (OPN), osteocalcin (OC), and osteonectin (ON) was analyzed by in situ hybridization. Bone tissue was formed in the tumors derived from Hu09 cells. OPN mRNA was transcribed predominantly in osteocyte-like cells within the bone, whereas OC mRNA was transcribed in osteoblast-like cells that surrounded the bone. ON mRNA was detected in both types of cells. The similarity of the expression pattern of OPN, OC, and ON during osteogenesis of Hu09 cells to that of normal skeletal development suggests that the bone formed in Hu09-implanted mice is the same as normal bone tissue. By DNA-DNA in situ hybridization using a human-specific Alu probe and a mouse-specific m-L1 probe, osteoblast-like cells in Hu09 tumorous bone were, however, of human origin, whereas osteocyte-like cells were of mouse origin. In the tumors derived from OST cells, no osteogenesis was observed during the experimental period, and the expression of OPN, OC, and ON was not detected in tumor cells. An endochondral bone formation was not evident when these cells were simply implanted into muscle tissue. An endochondral bone was, however, reactively induced in the host mUscle tissue either when 1 alpha-hydroxyvitamin D3 and all-transretinoic acid were administered to OST-implanted mice or when Hu09 cells were pretreated with dexamethasone before implantation. Hu09 implantation seems to be a useful tool not only for the study of the differentiation of osteosarcoma cells but also for the investigation of the mechanism of bone formation. This system, using Hu09 and OST, may provide us with a new tool for the isolation of the unidentified factors that induce or inhibit osteogenesis in vivo.
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PMID:In vivo implantation of human osteosarcoma cells in nude mice induces bones with human-derived osteoblasts and mouse-derived osteocytes. 894 Dec 16

A cisplatin (CDDP)-resistant human osteosarcoma cell line (OST/R) was established by continuous exposure to CDDP. OST/R cells proved to be 6.73 times more resistant to CDDP compared with parental OST cells, and showed cross-resistance to carboplatin (CBDCA). The mechanism of CDDP resistance was a significant decrease of intracellular platinum accumulation which was 40% of that in OST cells. OST/R cells were exposed to CDDP for 6 hours, the platinum was released from the cytoplasm of OST/R cells without reaching a state of equilibrium. DNA synthesis in OST/R cells was not inhibited by CDDP exposure, while in OST cells it was reduced by 50%. These data provide the first evidence that the increased efflux of platinum may play an important role in CDDP-resistance.
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PMID:Establishment and characterization of an acquired cisplatin-resistant subline in a human osteosarcoma cell line. 967 2


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