The effect of 1:2 Ag(I) thiocyanate complexes in MCF-7 breast cancer cells

Abstract

There is much interest currently in the design of metal compounds as drugs and various metal compounds are already in clinical use. These include gold(I) compounds such as auranofin and the anti-cancer platinum(II) complex, cisplatin. Bis-chelated gold(I) phosphine complexes have also shown great potential as anticancer agents, however, their efficacy has been limited by their high toxicity. In this study, silver(I) thiocyanate compounds linked to four specific ligands, were synthesized and characterized. These silver-phosphine adducts included [AgSCN{P(4-MeC6H4)3}2]2 (1); [AgSCN{P(4-ClC6H4)3}2]2 (2); [AgSCN{P(4-MeOC6H4)3}2]2 (3); [AgSCN(PPh3)2]2 (4). The compounds were found to be toxic to MCF-7 breast cancer cells while the ligands on their own were not toxic. Our findings further indicate that the silver(I) phosphine compounds induce apoptotic cell death in these breast cancer cells. In addition, the compounds were not toxic to nonmalignant fibroblast cells at the IC50 concentrations. This is an indication that the compounds show selectivity towards the cancer cells.

The selective cytotoxicity of silver thiosulfate, a silver complex, on MCF-7 breast cancer cells through ROS-induced cell death

“…2c), indicating the cytotoxicity of STS on a visual basis. Some studies have reported that the anticancer effect of silver complexes is not due to ligands but due to the silver element itself [18], which was also supported by the results of the present research (i.e., no cytotoxicity with sodium thiosulfate, which is the ligand of STS, as shown in Fig. 3d).…”

Apoptosis-inducing ability of silver(I) cyanide-phosphines useful for anti-cancer studies

“…Complex 1 had a low IC 50 value of 4.02 lM when compared to the IC 50 of cisplatin (47.39 lM). This marked degree of toxicity between this class of silver(I) complexes and cisplatin was previously reported (Ferreira et al 2015;Human et al 2015;Potgieter et al 2015). Furthermore, silver(I) saccharinate complexes with monophosphines (Yilmaz et al 2014) including silver(I) salicylic acid with triphenylphosphine (Poyraz et al 2011) showed improved cytotoxicity in malignant cells when compared to cisplatin.…”

“…In contrast, other silver(I) phosphine complexes were less, or had comparable, cytotoxic activities for normal cells than for the malignant cells (Poyraz et al 2011;Yilmaz et al 2014). In one study, a silver thiocyanate (AgSCN) complex selectivity was determined in the same non-malignant cell lines studied herein (Ferreira et al 2015). This complex is structurally similar to complex 1 with the only difference being a SCN linked to the silver rather than CN.…”

“…However, literature on the mechanism of the silver(I) complexes as potential anticancer drugs was limited until recently. The apoptotic inducing ability of a number of Ag(I) complexes in malignant cell lines have been reported recently (Ferreira et al 2015;Human et al 2015;Potgieter et al 2015).…”

Silver coordination compounds: A new horizon in medicine

“…All four complexes possessed cytotoxic activity against this tumor cell line, inducing apoptotic cell death, while the ligands on their own were not toxic. Furthermore, this antiproliferative action seemed to be selective towards the MCF-7 line, since the complexes were not toxic to nonmalignant fibroblast cells at the IC50 concentrations [74].…”