Tamoxifen does not form detectable DNA adducts in white blood cells of breast cancer patients

Abstract

DNA from white blood cells of seven women receiving tamoxifen as adjuvant therapy for breast cancer and of three women who served as healthy controls was analysed for the presence of tamoxifen-DNA adducts using 32P-postlabelling with a limit of detection of 8 adducts/1010 nucleotides. No postlabelled adducts with the chromatographic properties of known tamoxifen-DNA adducts were detected in any of the samples. It is concluded that at therapeutic levels of exposure there is no significant formation of DNA adducts by tamoxifen or its metabolites in circulating white blood cells.