Background: A broad range of metal-coordinated complexes have been studied for their anticancer
activities. However, some of these complexes display high toxicity profiles to non-malignant cells, therefore
limiting their use in cancer therapeutics.
Aims/Method: Several silver(I) triphenylphosphine adducts were prepared as 1:1 to 1:4 ratios of silver nitrate to
triphenylphosphine. They were further used to determine their anticancer activity in a malignant SNO esophageal
cell line. The silver(I) phosphine adducts include: [Ag(PPh3)]NO3 (1); [Ag(PPh3)2]NO3 (2); [Ag(PPh3)3]NO3
(3) and [Ag(PPh3)4]NO3 (4). In addition, the activity of complexes 1-4 was compared to previously reported
complexes [Ag(Ph2P(CH2)2PPh2)2]NO3 (5) and [Ag(Ph2P(CH2)3PPh2)2]NO3 (6). The cytotoxicity of complexes
1-6 was also evaluated in non-malignant human dermal fibroblast cells (HDF-a).
Results: The majority of the complexes (specifically those containing PPh3) were found to be highly toxic to the
SNO cells and less toxic towards HDF-a cells, as determined by the alamarBlue® assay. Morphological studies
and flow cytometry confirmed that the silver(I) complexes induced apoptosis in the malignant cells.
Conclusion: These results may have an impact on research related to drug discovery and silver(I) phosphine complexes
could be added to the arsenal of anticancer agents in addition to the silver-bis-diphenylphosphinoethane
and silver-bis-diphenylphosphinopropane adducts.