Anticancer activity studies of ruthenium(II) polypyridyl complexes against human gastric carcinoma SGC-7901 cell

Abstract

A new ligand TCPI and its three ruthenium(II) polypyridyl complexes [Ru(N-N)2(TCPI)](PF6)2 (N-N=bpy: 2,2′-bipyridine 1; phen: phenanthroline 2; dmp: 2,9-dimethyl-1,10-phenanthroline 3) were synthesized and characterized by elemental analysis, ESI-MS, 1H NMR, IR, absorption and emission spectra. The cytotoxic activity in vitro of the ligand and complexes against cancer cells SGC-7901, PC-12, HepG-2, SiHa, Eca-109, HeLa and normal cell LO2 was evaluated by MTT method. Complex 3 shows the highest cytotoxic activity toward SGC-7901 cell among the complexes. Interestingly, the complexes show low or no cytotoxic activity against normal cell LO2. The apoptosis in SGC-7901 cell was investigated with AO/EB staining method. The ROS levels and the changes of mitochondrial membrane potential were studied under fluorescent microscope and flow cytometry. The cell invasion, cell cycle arrest and the expression of Bcl-2 family proteins were studied in detail. The results demonstrate that the complexes induce apoptosis in SGC-7901 cell through a ROS-mediated mitochondrial dysfunction pathway, which was accompanied by the regulation of Bcl-2 family proteins.