학술논문

Ruthenium(II)-mercapto Complexes with Anticancer Activity Interact with Topoisomerase IB
Document Type
article
Source
Journal of the Brazilian Chemical Society. March 2020 31(3)
Subject
ruthenium(II) complexes
mercapto ligands
cytotoxicity
topoisomerase IB
Language
English
ISSN
0103-5053
Abstract
Herein we present four new ruthenium(II) complexes: [Ru(mtz)2(dppb)] (1), [Ru(mmi)2(dppb)] (2), [Ru(dmp)2(dppb)] (3), and [Ru(mpca)2(dppb)] (4), where mtz = 2-mercaptothiazoline; mmi = 2-mercapto-1-methyl-imidazole; dmp = 4,6-diamino-2-mercaptopyrimidine; mpca = 6-mercaptopyridine-3-carboxylic acid; dppb = 1,4-bis(diphenylphosphino)butane. In vitro cell culture experiments revealed cytotoxic activity for complexes 2, 3 and 4 against MCF-7 (breast, non-invasive), MDA-MB-231 (breast, invasive), A549 (lung), DU-145 (prostate) and HepG2 (liver) tumor cells, in some cases lower than the half maximal inhibitory concentration (IC50) for the reference drug (cisplatin). The deoxyribonucleic acid (DNA) interactions studied by viscosity measurements, gel electrophoresis and square-wave voltammetry indicated that the DNA binding affinity primarily occurs through non-covalent interactions. Only complex 2 was able to fully inhibit the DNA supercoiled relaxation mediated by human topoisomerase IB (Top IB). The analysis indicates that complex 2 inhibits the cleavage and the reconnection steps of the catalytic cycle, being both a poison and a catalytic inhibitor.