PO-416 Cytotoxicity of Ru (II) and Ru (III) salen complexes against breast and colorectal cancer cell lines

Abstract

Introduction Breast and colorectal cancer are the most common cancers, and are therefore responsible for a high mortality rate worldwide. The search for new anticancer drugs has increased in the last decades since chemotherapeutic drugs used nowadays show many adverse effects and cancer resistance. Previous studies have shown that metallic salen complexes exhibit antitumor activity. Additionally, Ru complexes have revealed cytotoxic activity, proving greater selectivity for tumour cells. They are less toxic relatively to Pt complexes, being for this reason pointed out in the literature as a credible alternative to current drugs used in chemotherapy. The aim of this study is to synthesise four novel Ru(III) and Ru(II) chlorinated salen complexes and test their cytotoxicity on breast and colorectal cancer cell lines. Material and methods Ru salen complexes were synthesised from camphoric acid derivatives. MCF-7 and HCC1806 breast cancer cell lines and LS1034 and WiDr colorectal cancer cell lines were cultured in appropriate culture medium. The effect of the compounds on cell metabolic activity was evaluated by colorimetric MTT (3-(4,5-dimethylthiazol-2-yl)−2,5-diphenyltetrazolium bromide) test. For this study, the cells were seeded in 48-well plates and after 24 hour were incubated with increasing concentrations of the complexes (0.5 to 200 µM). After 48 hour, cell proliferation was evaluated through MTT assay. Dose response curves were plotted and IC50 (half maximal inhibitory concentration) values for each ruthenium complex were determined. Results and discussions All compounds induced a decrease in cell proliferation in a dose-dependent way. For breast cancer MCF-7 and HCC1806 cell lines the tetrachlorinated Ru(III) complex presents greater cytotoxicity (IC50 Conclusion All compounds revealed dose-dependent anti-proliferative effects. The tetrachlorinated Ru(III) complex was found to be the most promising, exhibiting high anticancer activity in all cell lines, namely in the HCC1806 and LS1034 chemoresistant cell lines.