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)

Vitamin A is known to be able to modulate cell growth and differentiation and to act as an inhibitor of the process of carcinogenesis in some experimental models. Here we have studied the effect of different concentrations of vitamin A on chemotactic and chemoinvasive behaviour of a metastatic osteosarcoma cell line. The cell proliferation was partially inhibited in the presence of 10(-5) M retinol after 4 days of incubation. Retinol effect on chemotactic and chemoinvasive activity of osteosarcoma cells seemed to be dose-dependent. The highest retinol concentration used (10(-5) M) had an inhibitory effect on migratory and invasive cell response. Lower retinol concentrations seemed to be able to enhance (10(-8) M) both chemotactic and chemoinvasive activity of osteosarcoma cells. Chemotaxis and chemoinvasion assays provide rapid and quantitative tools to study the "in vitro" behaviour of metastatic cells. Furthermore, they represent a mean to screen for drugs, hormones and other substances able to alter the metastatic phenotype.
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PMID:Effect of vitamin A on chemotactic and chemoinvasive behaviour of an osteosarcoma cell line. 239 Feb 27

Retinol and retinoic acid at 20 microM altered cell morphology and inhibited cell proliferation of UMR 106 osteosarcoma cells in culture. No specific cytosolic binding proteins for retinol could be detected.
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PMID:Vitamin A effects on UMR 106 osteosarcoma cells are not mediated by specific cytosolic receptors. 386 50

The in vivo carcinogenic risk of hyperthermia, alone or in combination with irradiation, and the anti-carcinogenic potential of vitamin A and N-acetylcysteine (AcCys) were investigated. Starting 1 month before treatment, 160 rats were divided into four diet groups: no additives, vitamin A-enriched diet, AcCys and the combination vitamin A + AcCys. In 10 animals per diet group, the hind leg was treated with either X-irradiation alone (16 Gy), hyperthermia alone (60 min at 43 degrees C), hyperthermia 5 h prior to irradiation or hyperthermia 5 h after irradiation. Animals were observed for 2 years after treatment with regard to the development of tumours either inside or outside the treated volume. After 16 Gy alone 12 +/- 5% of the animals developed a tumour. Tumour incidence increased to 37 +/- 9% (borderline significance P = 0.07 versus treatment with X-rays alone) when hyperthermia was applied prior to X-rays, and to 24 +/- 8% (NS) with hyperthermia after irradiation. The relative risk ratio (RRR) for tumour induction was increased to 2.4 by hyperthermia if combined with X-irradiation. Pathological characterization of induced tumours showed that these were of the fibrosarcoma, osteosarcoma and carcinoma type. Vitamin A alone or in combination with AcCys slightly protected against the induction of tumours by X-rays without or with hyperthermia (RRR of 0.4). However, morphological changes such as lipid accumulation in hepatocytes and damage to the parenchyma were noticed in livers from all animals that were given a vitamin-A-enriched diet (P < 0.0001). Data from the present and past reports show that hyperthermia alone is not carcinogenic, but that it may increase radiation carcinogenesis. Treatment temperature and time of exposure to heat in addition to the radiation dose applied are important factors in the carcinogenic process. The enhancement of radiation carcinogenesis seems to occur independently of the sequence and time interval between irradiation and hyperthermia. However, not all data are consistent with this interpretation.
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PMID:Hyperthermia, radiation carcinogenesis and the protective potential of vitamin A and N-acetylcysteine. 864 44

Vitamin A targeting to bones is a suitable treatment for osteoporosis. In this study, we have developed vitamin A-encapsulated liposomes that can be useful to deliver vitamin A to the bones in a selective manner. This liposomal formulation of vitamin A has been found to be stable for >6 months as no significant change in size and charge occurred. Vitamin A liposomes-induced cell proliferation in SaOS-2 (human osteosarcoma cell line) and release kinetics study concluded that the liposomal formulation of vitamin A gives a controlled release of vitamin A in comparison to the free vitamin. The MTT assay showed the proliferation of SaOS-2 cells after their treatment with vitamin A liposomes.
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PMID:Liposomal formulation of vitamin A for the potential treatment of osteoporosis. 2959 95