SOD1 and cancer: Zhou et al. (16) have compared cells lacking mtDNA with normal cells and showed that the absence of mitochondria reduced mutagenesis in bystander cells through inhibiting the expression of other genes involved in this process such as COX-2 and iNOS. Since lung cancer is one of most common cancer after pelvis radiotherapy; therefore, this study aimed to evaluate oxidative damage to out-of-field lung tissue 24 and 72 hours after pelvic irradiation in rats using the measurement of the malondialdehyde (MDA) and glutathione (GSH) levels as well as superoxide dismutase (SOD) activity.