A potential role for protein tyrosine phosphatase inhibition by a RuIII-edta complex (edta = ethylenediaminetetraacetate) in its biological activity.

[RuIII(edta)(OH2/OH)]1-/2- (edta = ethylenediaminetetraacetate) inhibits protein tyrosine phosphatase (PTP) at physiological pH values in a mechanism that involves binding of the Cys residue of the catalytic domain of the enzyme and similar interactions may be important in the anti-cancer properties of the active forms of many Ru pro-drugs.