Investigation on anticancer activity of new Ni(II) cuminaldehyde based benzhydrazone complexes

Abstract

The research aims to find an efficacious anticancer agents of three new Ni(II) complexes containing cuminaldehyde based benzhydrazide ligands(L) with lesser side-effects. The complexes possessing the composition of [Ni(L)2] were characterized by analytical and spectral techniques(FT-IR, UV–vis, NMR, and HRMS). The square planar geometry of the complex 3 was authenticated by single-crystal X-ray diffraction and reveals the bidentate mode of coordination of the ligands in either side of the nickel (II) ion via imidolate oxygen and azomethine nitrogen resembling a butterfly. The cytotoxic efficiency of the complexes in inhibiting the growth of human cervical cancer cells (HeLa) and human colon carcinoma (HT-29) has been studied along with the cell viability assay against the non-cancerous fibroblast (L929) under in vitro condition by MTT assay. The results showed that all the three complexes displayed good cytotoxicity against the cancer cells with low IC50 values in the range 77.23 μM − 44.05 μM. In particular, complex 3 displayed excellent cytotoxicity against HT-29 cancer cells out of the three complexes with the IC50 value of 44.05 μM. This may be due to the electron releasing group (–OCH3) in the complex 3 which increases lipophilicity and enhances the permeability through the cell membrane. Further, the apoptotic mode of cell death in the cancer cells was assessed via AO–EB and Hoechst 33258 staining methods. In addition, reactive oxygen species (ROS), mitochondrial membrane potential (MMP) and flow cytometry methods were demonstrated to confirm the cell death in cancer cells through apoptosis.