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

I.H. Zwingmann, I.J. Welle, J.J.M. Engelen, P.A.E.L. Schilderman-Houba, J.M.A. de Jong, J.C.S. Kleinjans

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

Department of Health Risk Analysis and Toxicology, Maastricht University, Netherlands.

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-oxodG/dG) 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.
Original languageEnglish
Pages (from-to)361-369
Number of pages9
JournalMutation Research-Fundamental and Molecular Mechanisms of Mutagenesis
Volume431
Issue number2
DOIs
Publication statusPublished - 1 Jan 1999

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