Abstract
The bidentate N-cyclohexyl-2-(3-hydroxy-4-methoxybenzylidene)hydrazine-1-carbothioamide Schiff base ligand (HL) was coordinated to divalent nickel, palladium and platinum ions to form square planar complexes. The nickel and palladium complexes, [NiL
], [PdL
] form square planar complexes with 2:1 ligand to metal ratio. The platinum complex, [PtL(dmso)Cl] formed a square planar complex with 1:1 ligand to metal ratio. Platinum undergoes in situ reaction with DMSO before complexing with the ligand in solution. The cytotoxicity of HL, [NiL
], [PdL
], and [PtL(dmso)Cl] were evaluated against human colon cancer cell line (HCT-116), human cervical cancer (Hela) cell line, melanoma (B16F10) cells, and human normal endothelial cell lines (Eahy926) by MTT assay. The [NiL
] complex displayed selective cytotoxic effect against the HCT 116 cancer cell line with IC
of 7.9 ± 0.2 μM. However, HL, [PdL
], and [PtL(dmso)Cl] only exhibited moderate cytotoxic activity with IC
= 75.9 ± 2.4, 100.0 ± 1.8, and 101.0 ± 3.6 μM, respectively. The potent cytotoxicity of [NiL
] was characterized using Hoechst and Rhodamine assays. The nickel complex, [NiL
], caused remarkable nuclear condensation and reduction in mitochondrial membrane potential. In addition, molecular docking studies confirms that [NiL
] possesses significant binding efficiency with Tyrosine kinase. Altogether, the results revealed that [NiL
] exhibits cytotoxicity against the cancer cells via Tyrosine kinase-induced proapoptosis pathway. This study demonstrates that the [NiL
] complex could be a promising therapeutic agent against colorectal carcinoma.