Effects of EGCG on DNA cleavage site utilization by topoisomerase II. Data for human topoisomerase IIα (hTIIα; left) and topoisomerase IIβ (hTIIβ; right) are shown. Autoradiograms of polyacrylamide gels are shown. DNA cleavage reactions contained enzyme in the absence of compounds (hTIIα or hTIIβ), or in the presence of 12.5 μM etoposide (Etop), 50 μM genistein (Gen), 25 μM 1,4-benzoquinone (BQ), or 25–500 μM EGCG. A DNA control is shown in the far left lane of each autoradiogram (DNA). Data are representative of three independent experiments.