, Volume 28, Issue 1, pp 219–228 | Cite as

The induction of cell death by phosphine silver(I) thiocyanate complexes in SNO-esophageal cancer cells

  • Zelinda Human
  • Appollinaire Munyaneza
  • Bernard Omondi
  • Natasha M. Sanabria
  • Reinout Meijboom
  • Marianne J. CronjéEmail author


Esophageal cancer is one of the least studied cancers and is found to be prominent in black South African males. It is mainly diagnosed in the late stages, and patients tend to have a low 5-year survival rate of only 10 %. Silver is generally used as an antimicrobial agent, with limited reports on anticancer studies. In this study, dimeric silver(I) thiocyanate complexes were used containing a variation of 4-substitued triphenylphosphines, including [AgSCN(PPh3)2]2 (1), [AgSCN{P(4-MeC6H4)3}2]2 (2), [AgSCN{P(4-FC6H4)3}2]2 (3) and [AgSCN{P(4-ClC6H4)3}2]2 (4). All four complexes, with their respective phosphine ligands, PPh3 (L1), P(4-MeC6H4)3 (L2), P(4-FC6H4)3 (L3) and P(4-ClC6H4)3 (L4), were subjected to in vitro toxicity studies in SNO-esophageal cancer cells, using an alamarBlue® assay. Morphological changes, including blebbing and apoptotic body formation, were observed. Phosphatidylserine externalization, a marker of apoptosis, was quantified by flow cytometry. The phosphine ligands L1L4, on their own, had minimal effect on the malignant while complexes 14 resulted in significant cell death. A 10× decreased concentration of these complexes had similar effects than cisplatin, used as the positive control. These complexes show promise as anticancer agents.


Silver(I) thiocyanate complexes Phosphines Anticancer Flow cytometry Apoptosis SNO-esophageal cancer 



The authors gratefully acknowledge financial assistance from the University Research Council of the University of Johannesburg, SASOL, TESP, CANSA. This work is based on the research supported in part by the National Research Foundation of South Africa (Grant specific unique reference number (UID) 85386). The University of Pretoria is thanked for the gift of SNO-esophageal cancer cells.

Supplementary material

10534_2014_9817_MOESM1_ESM.docx (42 kb)
Supplementary material 1 (DOCX 42 kb)


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Zelinda Human
    • 1
  • Appollinaire Munyaneza
    • 2
  • Bernard Omondi
    • 2
  • Natasha M. Sanabria
    • 1
    • 2
  • Reinout Meijboom
    • 2
  • Marianne J. Cronjé
    • 1
    Email author
  1. 1.Department of BiochemistryUniversity of JohannesburgAuckland Park, JohannesburgSouth Africa
  2. 2.Department of Chemistry, Research Centre for Synthesis and CatalysisUniversity of JohannesburgAuckland Park, JohannesburgSouth Africa

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