Figure 4

Comparative study of calcium effect on zoledronic acid or paclitaxel, and magnesium effect on ibandronate. Cells were exposed for (a) 72 hours to increasing concentrations of zoledronic acid (1 to 1,000 μmol/l) or (b) to increasing concentrations of paclitaxel (0.1 to 1,000 μmol/l), in culture medium containing 0.6 mmol/l calcium (filled squares) or 1.6 mmol/l calcium (open squares), or (c) to 30 μmol/l ibandronate (open circles) in the presence of increasing magnesium concentrations (0.4 to 1.8 mmol/l; filled circles, no ibandronate). Cell culture densities were measured by crystal violet staining assay. Data are presented as percentages (mean ± standard deviation) of control values, which refer to culture with 0.6 mmol/l calcium or 0.4 mmol/l magnesium and without drug. Mean of results pooled from two experiments (n = 12).