Ionizing Radiation Upregulates Glutamine Metabolism and Induces Cell Death via Accumulation of Reactive Oxygen Species

Figure 3

Ionizing radiation enhances oxidative stress in tumor cells. MCF-7 and HCT-116 cells were irradiated with X-rays at different doses. The morphology of the mitochondria of MCF-7 cells was observed by transmission electron microscopy (a). Immunofluorescence staining showed that X-rays caused mitochondrial shrinkage (b). DHR123 staining showed that X-rays induced ROS accumulation in mitochondria in a dose-dependent manner (c). 2 Gy X-ray irradiation increased the peroxidation index of the MCF-7 tumor cells (d). Inhibition of glutamine metabolic flux reduces the accumulation of ROS (e) and reduces DNA damage (f, g) induced by ionizing radiation. of triplicate assessments, one-way ANOVA with post hoc Dunnett test, , and (b, c). Student’s unpaired -test, (d). One-way ANOVA with post hoc Dunnett test, , , and (e–g).

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