Figure 2

Concentration-effect relationships of ibandronate on cancer cell proliferation in hypocalcaemic or hypercalcaemic conditions. MDA-MB-231 and MCF-7 cells were exposed for 72 hours to increasing ibandronate concentrations (1 to 1,000 μmol/l) in culture medium containing 0.6 mmol/l calcium (filled squares) or 1.6 mmol/l calcium (open squares). Cell culture densities were evaluated by crystal violet staining assay. Data are presented as percentages (mean ± standard deviation) of control values, which refer to cultures with 0.6 mmol/l calcium and without ibandronate. Mean of results pooled from three experiments (n = 18). *P < 0.01 versus 0.6 mmol/l calcium, analysis of variance, Tukey post hoc test.