8-HYDROXYDEOXYGUANOSINE LEVELS IN DNA OF HUMAN BREAST CANCERS ARE NOTSIGNIFICANTLY DIFFERENT FROM THOSE OF NON-CANCEROUS BREAST TISSUES BYTHE HPLC-ECD METHOD

8-Hydroxydeoxyguanosine (oh(8)dG) is a promutagenic DNA lesion produce d by oxygen radicals, and a high level of 8-hydroxyguanine in breast c ancers was previously demonstrated by the gas chromatography-mass-spec trometry method, To confirm the previous observation, the oh(8)dG leve ls of DNA of 22 breast cancers and corresponding adjacent non-cancerou s breast tissues were analyzed by high performance liquid chromatograp hy-electrochemical detector (HPLC-ECD) system, and the correlation of the oh(8)dG levels in breast cancer DNAs with clinical and immunohisto chemical parameters was examined. However, the levels of oh(8)dG in DN A of breast cancers are not significantly different from those of corr esponding non-cancerous breast tissues (P=0.084) by the HPLC-ECD metho d. Furthermore, the oh(8)dG levels in breast cancers were not associat ed with p53 and erbB-2 immunoreactions, with expression of estrogen an d progesterone receptors, and with clinical stage and histological gra de. Thus, in contrast to the previous data, the present study using th e HPLC-ECD method does not indicate an increase of oh(8)dG levels in b reast cancers.