PT  - JOURNAL ARTICLE
AU  - MARIA TERESA SANTINI
AU  - ROCCO ROMANO
AU  - GABRIELLA RAINALDI
AU  - ANTONELLA FERRANTE
AU  - PAOLA INDOVINA
AU  - ANDREA MOTTA
AU  - PIETRO LUIGI INDOVINA
TI  - <sup>1</sup>H-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
DP  - 2006 Jan 01
TA  - Anticancer Research
PG  - 267--281
VI  - 26
IP  - 1A
4099  - http://ar.iiarjournals.org/content/26/1A/267.short
4100  - http://ar.iiarjournals.org/content/26/1A/267.full
SO  - Anticancer Res2006 Jan 01; 26
AB  - 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. Copyright© 2006 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved