Role of Glutathione in Apoptosis Induced by Radiation as Determined by 1H MR Spectra of Cultured Tumor Cells

Abstract Rosi, A., Grande, S., Luciani, A. M., Palma, A., Giovannini, C., Guidoni, L., Sapora, O. and Viti, V. Role of Glutathione in Apoptosis Induced by Radiation as Determined by 1H MR Spectra of Cultured Tumor Cells. Radiat. Res. 167, 268–282 (2007). The relationship between apoptosis induced by γ radiation and glutathione in cells of two human cancer cell lines, HeLa from cervix carcinoma and MCF-7 from mammary carcinoma, was examined. MCF-7 cells appeared to be more radioresistant than HeLa cells, and radiation-induced apoptosis, which was monitored by assessing phosphatidylserine externalization, was observed in HeLa cells but not in MCF-7 cells. Glutathione levels monitored by 1H MRS were higher in MCF-7 cells than in HeLa cells, while the opposite was true for the free glu signals. MCF-7 cells became more radiosensitive when treated with 0.1 mM buthionine sulfoximine, which inhibits GSH synthesis through inactivation of γ-glutamylcysteine synthetase, with the concomitant appearance of radiation-i...