Cytotoxic effects of gold(I) complexes against colon, cervical and osteo carcinoma cell lines: A mechanistic approach
Water-soluble gold(I) complexes of the type [Au(Ipr)(L)]PF6, where L = thiourea (Tu) 1 and N,N'-dimethylthiourea (Me2Tu) 2 synthesized from the parent 1,3-Bis(2,6-di-isopropylphenyl)imidazol-2-ylidenechloridogold(I) [(Ipr)AuCl] 0. The complexes (0-2) fully characterized using elemental analysis (EA), FT-IR, 1H and 13C NMR. Single crystal X-ray diffraction analysis shows both complexes have a near linear geometry. We investigated the in vitro cytotoxic activity of the complexes and cisplatin using an MTT assay against Human osteosarcoma (MG-63), colon adenocarcinoma (HCT15), and cervical cancer cell line (HeLa) cell lines. The IC50 values show the complexes 1 and 2 exhibited cytotoxicity higher than cisplatin against all cancer cell lines. The complex 2 exhibited cytotoxicity less than cisplatin against HeLa. The interaction of the complexes with amino acids tested electrochemically in a phosphate buffer aqueous solution using cyclic voltammetry. Complex 1 interacted more with L-tryptophan than complex 2. The interaction of both complexes with L-tryptophan observed the reduction in peak height and peak current with L-tryptophan. Studying the expression levels of Caspase-3 and Caspase-9 gene measured the cell death mechanism. The treatment of the HCT-15 and HeLa cells with complex 1 resulted in the induction of apoptosis and a significant up-regulation in the expression of both caspase-3 and 9. No significant deviation noted in the expression of the MG-63 cells treated with complex 1.