Sister chromatid exchange in peripheral blood lymphocytes as a possible breast cancer risk biomarker: A study of Iranian patients with breast cancer

Introduction: Sister chromatid exchanges (SCEs) can be induced by variousgenotoxic treatments, suggesting that SCEs refl ect a DNA repair process and it may be a good index for assessment of genomic instability. However, the occurrence of genetic instability and in particular, of spontaneous SCEs has been strongly linked to cancer. Several chromosomal regions and many genes have been implicated in breast cancer.Materials and Methods: Blood samples were obtained from 31 Iranian breast cancer patients and 11 healthy women. SCE was measured in peripheral blood lymphocytes by adding to Ham’sF10 medium in presence of PHA, BrdU (5-bromo-deoxy Uridine) fl uorochrome Hoechst 33258, exposure to UV light and Giemsa staining. Then, SCE frequencies of patient and control groups were compared by the Mann-Withney U-test.Results: Signifi cantly difference was observed between two groups (