ABSTRACT
Apoptosis could be a major mechanism of antitumor effect of tamoxifen. Therefore this study is designed to characterize the kinetic behavior of tamoxifen-induced apoptosis in the estrogen receptor positive [ER+] and negative [ER-] cell lines, MCF-7 and MDA-MB-468. Frequency of cell death was examined by trypan blue and acridine orange staining. Annexin V-Fluorescein/PI was used in flow cytometry for distinguishing the dividing, apoptotic and necrotic cells and Hoechst 33258 staining was also applied to detect apoptotic changes in the nuclear morphology. The results showed that tamoxifen was able to induce apoptosis in both cell lines [