Fig 9. Effects of iron on 1, 2 and 5 activity.

(A) Effect of 2 h FeCl₂ pre-incubation (FeCl₂ p) (dotted line) or co-incubation (FeCl₂ c) (dashed line) at 1, 10 or 100 μmol/L on the cytotoxicity of 2 (5 μmol/L) in MCF-7 and CAPAN-1 cells. FeCl₂ alone was included as a control (solid line). Cell viability was determined after 48 h of treatment by the MTT assay. (B) Effect of FeCl₂ pre-incubation or co-incubation (100 μmol/L) on the cytotoxicity of 2 (5 μmol/L), 1 and 5 (10 μmol/L). Cells treated with the ligands alone were included as a reference (control). (C) ROS induction in CAPAN-1 cells after 24 h treatment with 2 (10 μmol/L) alone, together with FeCl₂ or after FeCl₂ pre-incubation (at 100 μmol/L). Results are presented as a percentage of untreated cells and represent mean±SD of 3 independent experiments. *p < 0.05 versus control cells.