Analysis of oxidative DNA damage and HPRT mutant frequencies in cancer patients before and after radiotherapy

作者：Zwingmann IH; Welle IJ; Engelen JJM; Schilderman PAEL; de Jong JMA; Kleinjans JCS^*

来源：Mutation Research-Fundamental and Molecular Mechanisms of Mutagenesis, 1999, 431(2): 361-369.

DOI：10.1016/S0027-5107(99)00179-7

• radiotherapy
• oxidative DNA damage
• HPRT mutant frequency
• micronuclei

Various markers of radiation-induced DNA damage including DNA oxidation were investigated in peripheral lymphocytes of 23 cancer patients prior to and one week after receiving radiotherapy with a cumulative dose of 54-70 Gy. Exposure to ionizing radiation nonsignificantly increased the ratio 2' deoxy-7-dihydro-8-oxoguanosine/2'deoxyguanosine (8-oxodC/dC) from 1.73 X 10(-5) to 3.33 X 10(-5). Frequencies of micronuclei significantly (p = 0.0003) increased from 6.4 to 38.9 per 1000 cells. The frequency of hypoxanthine-guanine-phosphoribosyltransferase (HPRT) mutant lymphocytes measured as 6-thioguanine resistant variant cells by 5-bromodeoxyuridine labeling, was elevated eight-fold, from 4.7 X 10(-6) to 36.2 X 10(-6) (p = 0.008) after termination of the radiotherapy, thus showing a clear response to the radiation treatment. No correlation between levels of oxidative DNA damage and frequencies of HPRT mutant lymphocytes or micronuclei could be established.

• 出版日期1999-12-17