The cytotoxicity of four Co(III) complexes of arginine on nontumour MDBK cells and on two cell lines
derived from transplantable tumors, LSCC-SF(Mc29) and LSR-SF (SR), was evaluated comparative!y. Based on the
cytotoxic concentration required to inhibit cell surveillance by 50% (CC50)
it was found that: (i) the cytotoxicity of
complexes tested increases when the concentration decreased; (ii) the cell surveillance depends on both complex and
cell specificities. The complex specificity was illustrated by the order 1 > 4 > 2 ≥ 3 . The cell specific response was
demonstrated by the fact that LSCC-SG (Mc29) cells were up to 60 times more sensitive to 1 while LSR-SF (SR)
cells were up to 1000 times more sensitive to 2 as compared to MDBK cells. Furthermore, with the prolongation of
action on nontumour cells the cytotoxicity of 4 decreased up to 300 times while for both tumour cells it was
independent on the duration of action.
