Establishment of the radiosensitivity predicting system by comet assay using peripheral lymphocytes

点击翻译按钮获取中文摘要

Twenty-nine patients with breast cancer who had developed Grade 2 acute radiation dermatitis following whole breast radiotherapy and 34 control patients who had not developed radiation dermatitis entered the present study. The patients' lymphocytes were irradiated at a dose of 12 Gy, and subjected to the single cell gel alkaline electrophoresis assay(comet assay) 0 to 180 minutes after irradiation. In most cases, standardized tail moment(STM) decreased with time, representing the repair procedure of radiation-induced DNA damage. The mean +/- SE of repair half-time(RHT), defined as the time required to reduce the STM to 50% of the STM at 0 min, in the dermatitis group and the control group was 31.0 +/- 4.8 min and 20.6 +/- 2.5 min(p=0.05), respectively. The results suggested that RHT, a parameter representing DNA repair velocity in ex vivo comet assay, may be a candidate for the radiation dermatitis predictor in patients receiving whole breast radiotherapy. Further evaluation of this assay in a prospective setting is indicated.