A Survey of Anticancer Effect of Some Five- and Six-Membered Palladium (II) Complexes (Containing Bidentate Phosphorus Ligands) on Caco-2 Colon Cancer Cell Line

Background and Objectives: Transition metal complexes possess a variety of biological and pharmacological activities, such as antitumor, antimicrobial, anti-inflammatory, anti-diabetic, and free radical scavenging. Many studies have been carried out on platinum-based chemotherapy agents, however, most attention has been paid to non-platinum metal-based agents in order to find different metal complexes with less side effects and similar cytotoxicity. This study was conducted with the objective of investigating the anticancer effect of various five- and six-membered palladium (II) complexes on colon cancer cell line.   Methods: In this study, in order to investigate the anticancer effect of 8 five- and six-membered palladium (II) complexes containing bidentate phosphorus ligands, the colon cancer cell line was treated for 24 h. Cell viability was studied using MTT assay. Also, in order to further study on the mechanism of action of these compounds, lipid peroxidation index was evaluated by TBA (thiobarbituric acid) test.   Results: In this study, the results were indicative of anticancer properties of five- and six-membered ring palladium complexes compared to the control group. Maximum cytotoxicity was shown in treatment of cells with C6 complex and the minimum cytotoxicity was found in treatment of the cells with C5 complex. Also, the results of TBA test indicated the anticancer property of five- and six-membered ring palladium complexes in comparison with the control group.   Conclusion: The comparison of inhibitory effect between five-membered palladium complexes (C1-C4) showed that the chlorine substituted complex (C1) had the highest effect on cell growth, while between six-membered palladium complexes (C5-C8), the bromine substituted complex (C6) had the highest effect on cell growth.