Designing anticancer copper(II) complexes by optimizing 2-pyridine-thiosemicarbazone ligands

Eur J Med Chem. 2018 Oct 5:158:442-452. doi: 10.1016/j.ejmech.2018.09.020. Epub 2018 Sep 10.

Abstract

To develop potential next-generation metal anticancer agents, we designed and synthesised five Cu(II) 2-pyridine-thiosemicarbazone complexes by modifying the hydrogen atom at the N-4 position of ligands, and then investigated their structure-activity relationships and anticancer mechanisms. Modification of the N-4 position with different groups caused significant differences in cellular uptake and produced superior antitumor activity. Cu complexes arrested the cell cycle at S phase, leading to down-regulation of levels of cyclin and cyclin-dependent kinases and up-regulation of expression of cyclin-dependent kinase inhibitors. Cu complexes exerted chemotherapeutic effects via activating p53 and inducing production of reactive oxygen species to regulate expression of the B-cell lymphoma-2 family of proteins, causing a change in the mitochondrial membrane potential and release of cytochrome c to form a dimer with apoptosis protease activating factor-1, resulting in activation of caspase-9/3 to induce apoptosis. In addition, Cu complexes inhibited telomerase by down-regulating the c-myc regulator gene and expression of the human telomerase reverse transcriptase.

Keywords: Anticancer; Cu(II) complexes; Telomerase; Thiosemicarbazone; p53.

MeSH terms

  • Antineoplastic Agents / chemistry*
  • Antineoplastic Agents / pharmacology*
  • Apoptosis / drug effects
  • Cell Cycle / drug effects
  • Cell Line, Tumor
  • Coordination Complexes / chemistry
  • Coordination Complexes / pharmacology
  • Copper / chemistry*
  • Copper / pharmacology*
  • Drug Design
  • Humans
  • Ligands
  • Membrane Potential, Mitochondrial / drug effects
  • Models, Molecular
  • Neoplasms / drug therapy
  • Neoplasms / metabolism
  • Pyridines / chemistry
  • Pyridines / pharmacology
  • Reactive Oxygen Species / metabolism
  • Telomerase / antagonists & inhibitors
  • Telomerase / metabolism
  • Thiosemicarbazones / chemistry*
  • Thiosemicarbazones / pharmacology*
  • Tumor Suppressor Protein p53 / metabolism

Substances

  • Antineoplastic Agents
  • Coordination Complexes
  • Ligands
  • Pyridines
  • Reactive Oxygen Species
  • Thiosemicarbazones
  • Tumor Suppressor Protein p53
  • Copper
  • Telomerase