Ibandronate-induced apoptosis in MCF-7 cells assessed by annexin-V fluorescein isothiocyanate and propidium iodide double staining (An/PI). Cancer cells were cultured for three to six days in steroid-free medium containing ibandronate (Iban) or vehicle (control). Apoptotic cells were detected as An+/PI- cells, while viable cells were An-/PI- cells and necrotic cells were PI+. (a) Representative dot plots after five days of Iban exposure. (b) The percentage of An+/PI- cells was determined from three experiments (mean ± SD). Statistical analysis on log transformed data; asterisks indicate ANOVA p < 0.01 versus corresponding control, Dunnett post hoc test.