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)

Using 31P-MR spectroscopy spectra with good signal-to-noise ratio were obtained in five different types of tumours (Ewing's sarcoma, osteosarcoma, malignant melanoma, metastases from a squamous cell carcinoma, parotid adenoma). Surface coils were used. Short- and long-term follow-up after chemotherapy was possible in some cases. In the short-term follow-up, changes in the phosphocreatine and inorganic phosphate resonances could be observed within minutes after the start of the infusion. In the longer follow-ups, changes in phosphodiester and phosphomonoester resonances were observed within two days. There were no significant changes in tissue pH during treatment, but increased pH values were observed in all tumours.
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PMID:[In vivo 31 phosphorus spectroscopy of tumors: pre-, intra- and post-therapy]. 284 3

The energy metabolism of Dunn osteosarcoma subcutaneously implanted in C3H/He mice was studied in vivo by a 31P-NMR spectrometer with surface-coils. The spectra of Dunn osteosarcoma showed peaks of sugar phosphate, inorganic phosphate, phosphocreatine, phosphomonoester, and ATPs. In the early stage of the tumor growth phosphocreatine and ATP showed large signal intensities and the tissue pH was 7.23 +/- 0.08. Following the tumor growth phosphocreatine and ATP decreased and the tissue pH fell to 6.82 +/- 0.08. Immediately after a small dose of MTX (2 mg/kg) was administered, an increase of inorganic phosphate and a decrease of phosphocreatine were temporarily observed when MTX concentrations of the tumor tissues were maximum. High energy metabolites were apparently consumed with the active transport of MTX. After twelve hours of a high dose of MTX (500 mg/kg) was administered, disappearance of phosphocreatine and ATP with an increase of inorganic phosphate was observed previous to the histological change. In vivo 31P-NMR spectroscopy may be useful in the evaluation of chemotherapy.
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PMID:[In vivo 31P-NMR studies on energy metabolism and the effect of methotrexate in murine implanted osteosarcoma]. 346 60

High resolution proton nuclear magnetic resonance (1H-NMR) spectroscopy was used to examine the response of the MG-63 osteosarcoma cell line grown in monolayer and as 3-dimensional tumor spheroids to the same low dose (2 Gy) of ionizing radiation. The MG-63 cells and spheroids were irradiated at 24 h of growth and the 1H-NMR spectra of whole control and irradiated monolayer cells and of whole control and irradiated multicellular spheroids collected after another 24 h were compared. The 1H-NMR spectra of the perchloric acid extracts as well as the 2-dimensional 1H-NMR spectra of both pairs of cell systems were also obtained. Possible radiation-induced cell damage was determined by lactate dehydrogenase (LDH) release and variations in cell growth, while cell death was evaluated by chromatin dye Hoechst staining and DNA fragmentation assays. The results demonstrated that no cell damage took place, but that significant variations in numerous metabolites occured in both the monolayer cells and the spheroids after irradiation. Most of the changes observed were very similar in nature. In fact, significant increases in lactate, alanine, creatine and phosphocreatine and choline-containing metabolites and a significant decrease in glutathione (GSH) were observed in both cells and spheroids. However, while significant increases in CH2 and CH3 mobile lipids, glutamine/glutamate, taurine and inositol were seen in the spheroids, no variations in CH2 or CH3 lipids, glutamine/glutamate or taurine were recorded in the MG-63 cells grown in monolayer after irradiation. In addition, a significant decrease rather than a significant increase in inositol was also noted in the monolayer cells. The data presented seem to suggest that, although neither monolayer cells nor spheroids show apparent signs of damage after exposure to the same dose of ionizing radiation, very different cell death responses as well as very diverse antioxidant/osmoregulatory reactions were triggered by this stressing agent.
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PMID:1H-NMR evidence for a different response to the same dose (2 Gy) of ionizing radiation of MG-63 human osteosarcoma cells and three-dimensional spheroids. 1647 7

The metabolic changes that occur as a function of time in MG-63 osteosarcoma three-dimensional tumor spheroids undergoing radiation-induced apoptosis were studied using high-resolution proton nuclear magnetic resonance ((1)H-NMR) spectroscopy. Specifically, the (1)H-NMR spectra of MG-63 spheroids collected at 24, 48 and 72 h after exposure to 5 Gy of ionizing radiation were compared to the spectra of their respective controls. Small spheroids (about 50-80 microm in diameter) with no hypoxic center were used. Apoptosis was verified by both staining of spheroid DNA with the Hoechst 33258 dye and determination of caspase 3 enzyme activity at the three times examined. The results demonstrate that, as the percentage of apoptosis rises with time after exposure to ionizing radiation, the metabolic changes that take place in MG-63 spheroids follow very precise temporal dynamics. In particular, significant time-related increases in both CH(2) and CH(3) mobile lipids, considered by many authors as markers of apoptosis, were observed. In addition, temporal variations were also observed in choline-containing metabolites, reduced glutathione (GSH), glutamine/glutamate, taurine, alanine, creatine/phosphocreatine and lactate. These data show that in addition to CH(2) and CH(3) lipids, other metabolites can also be extremely useful in a deeper understanding of the temporal dynamics of radiation-induced apoptosis. This comprehension is particularly important in spheroids, a cell model of great complexity that resembles in vivo tumors much more closely than monolayer cultures. Ultimately, it is hoped that such studies can help to evaluate the outcome of radiotherapy protocols more accurately.
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PMID:Temporal dynamics of 1H-NMR-visible metabolites during radiation-induced apoptosis in MG-63 human osteosarcoma spheroids. 1706 11

The glycolytic-based metabolism of cancers promotes an acidic microenvironment that is responsible for increased aggressiveness. However, the effects of acidosis on tumour metabolism have been almost unexplored. By using capillary electrophoresis with time-of-flight mass spectrometry, we observed a significant metabolic difference associated with glycolysis repression (dihydroxyacetone phosphate), increase of amino acid catabolism (phosphocreatine and glutamate) and urea cycle enhancement (arginino succinic acid) in osteosarcoma (OS) cells compared with normal fibroblasts. Noteworthy, metabolites associated with chromatin modification, like UDP-glucose and N(8)-acetylspermidine, decreased more in OS cells than in fibroblasts. COBRA assay and acetyl-H3 immunoblotting indicated an epigenetic stability in OS cells than in normal cells, and OS cells were more sensitive to an HDAC inhibitor under acidosis than under neutral pH. Since our data suggest that acidosis promotes a metabolic reprogramming that can contribute to the epigenetic maintenance under acidosis only in tumour cells, the acidic microenvironment should be considered for future therapies.
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PMID:Tumour-specific metabolic adaptation to acidosis is coupled to epigenetic stability in osteosarcoma cells. 2718 36