The effect of SIH and its analogs on ⁵⁹Fe mobilization from pre-labeled MCF-7 cells (A) and on internalized ⁵⁹Fe uptake from ⁵⁹Fe₂-transferrin (Tf) by MCF-7 cells (B).

<p>(<b>A</b>) The ability of the ligands to promote ⁵⁹Fe mobilization from MCF-7 cells was performed by first prelabeling the cells with ⁵⁹Fe₂-Tf (0.75 µM) for 3 h/37°C, followed by washing and then reincubation for 3 h/37°C with either control medium alone, or control medium containing the chelator (25 µM). (<b>B</b>) Inhibition of ⁵⁹Fe uptake from ⁵⁹Fe₂-Tf by MCF-7 cells by chelators was performed by incubating cells for 3 h/37°C with ⁵⁹Fe₂-Tf (0.75 µM) in the presence or absence of the chelator (25 µM). Results are Mean ±SD (<i>n</i>≥3 experiments). Statistical significance (ANOVA): * <i>p</i><0.05, ** <i>p</i><0.01, *** <i>p</i><0.001 compared to the control (untreated) group, and # <i>p</i><0.05, ## <i>p</i><0.01, ### <i>p</i><0.001 compared to the reference chelator, SIH.