Purpose: to investigate the cytotoxic activity of newly synthesized gold(III) complexes [AuCl(2)(en)](+), [AuCl(2) (SMC)](+), [AuCl(2)(DMSO)(2)(+) (en: ethylenediamine, SMC: S-methyl- L-cysteine and DMSO: for dimethylsulfoxide) in 4T1 mouse breast cancer cell line in vitro and in vivo and to compare their antitumor characteristics with cisplatin complex [PtCl(2)(NH(3))(2)].
Methods: the in vitro, effects of the tested complexes on 4T1 cell viability were determined using MTT colorimetric technique. In vivo, progression of mouse breast tumor growth in BALB/c mice was measured by using external caliper.
Results: among the tested gold(III) complexes, [AuCl(2) (en)](+) showed best cytotoxic effects in vitro. The cytotoxic effects of [AuCl(2)(en)](+) and [PtCl(2)(NH(3))(2)] were similar at all concentrations. The data from the in vivo experiment showed that among the tested gold(III) complexes only [AuCl(2)(en)](+) can prevent the primary breast tumor growth. [AuCl(2)(en)](+) was tolerated well and much better than [AuCl(2)(DMSO)(2)(+), [AuCl(2)(SMC)](+) and [PtCl(2)(NH(3))(2)] complex which was confirmed by weight gain in mice that received [AuCl(2)(en)](+). In addition, mice that received [AuCl(2)(en)](+) showed better survival time in comparison with mice that received [PtCl(2) (NH(3))(2)] complex.
Conclusion: [AuCl(2) (en)](+) complex seems to be good candidate for future pharmacological evaluation in breast cancer research.