Effects of various durations of exposure of MCF-7 cells to ibandronate. Cells were cultured in steroid-free medium and exposed to 10-4 M ibandronate or vehicle (control) for 1 to 72 h (pulse exposures). Cell growth measurements were performed after 72 h as described in Fig. 1. Asterisks indicate ANOVA p < 0.01 versus control, Tukey post hoc test. NS, not significant.