Synthesis And Anti-tumor Mechanism Studies Of Asymmetric Ruthenium(Ⅱ) Complexes

The high morbidity and mortality of cancer had received more attention. Chemical treatment as one of the main methods in treatment of cancer had acquired remarkable achievements in recent years. A variety of chemotherapy drugs with high inhibitory effect on cancer have been developed successfully and put into clinical use, such as carboplatin, oxaliplatin etc. Owing to the side effects of these drugs, scientists had set their sights in ruthenium complexes with high efficiency, low toxicity, and easy excretion.Four new ligands and sixteen asymmetric ruthenium metal complexes were synthesized and characterized in this paper, and the cytotoxicity in vitro of those complexes were assessed against different kinds of cells(Hep G-2, MG-63, Bel-7402, A549, He La). It has been confirmed that those complexes could cause apoptosis in the morphology by cellular uptake, AO/EB double dyes and Hoechst 33258 experiments. Scratching assay indicates that the complexes can effectively inhibit the cell migration. In addition, single cell gel electrophoresis experiment, flow cytometry, mitochondrial membrane potential detection, reactive oxygen species, western blot were also used to investigate the anti-tumor mechanism of those ruthenium metal complexes. The binding of bovine serum albumin of the ruthenium complexes was studied, which is of great significance for the ruthenium complexes in vivo of transportation including transport and distribution, meanwhile.The thesis was divided into six chapters.The first chapter is the introduction. The background and significance of this paper was described in this section. In the meantime, it expounded the progress of metal complexes on the antitumor activity and introduced the mechanism and methods of antitumor activity that involved in this paper.In chapter II, a ligand of DHBT that contained two hydroxyl groups and four new hydroxyl-containing ruthenium(II) polypyridyl complexes 2A, 2B, 2C, 2D were synthesized. The complexes show considerable activity toward the selected tumor cell lines. Complex 2B might arrest the cell cycle in G0 / G1 phase, while the complexes 2A, 2C, 2D blocked the cell cycle in S phase. At the same time, the four complexes could decrease the expression of anti-apoptotic protein Bcl-2 and upregulate expression of pro-apoptotic protein Bad. These complexes induce apoptosis by a ROS-mediated mitochondrial apoptosis pathway.In the chapter III, a symmetry ligand dqtbt and complexes 3A-3D were synthesized with 3, 3’-diaminobenzidine and benzil. Complexes 3A-3D showed with a lower IC50 value on Bel-7402 cells than cisplatin. Therefore, Bel-7402 cells were selected to explore the molecular mechanisms of the four complexes on anti-tumor activity.In chapter IV, a ligand AQTP and four relative complexes 4A-4D were synthesized. The complexes only performed a strong cytotoxicity on the selected cell line A549 which was meaningful on the screening of targeted antitumor metal drugs. In addition, apoptosis, cellular uptake, ROS, mitochondrial membrane potential, cell cycle arrest, western blot analysis induced by complexes 4A-4D were also studied in detail.In the fifth chapter, a ligand TBTIQ and complexes 5A-5D were synthesized and characterized. Mitochondrial membrane potential detection, detection of reactive oxygen species and western blot were performed which confirmed that complexes 5A-5D could induce cell apoptosis through the mitochondrial pathway. Complexes 5A-5D could combine with bovine serum albumin that caused the occurrence fluorescence quenching of bovine serum albumin.The sixth chapter is the conclusion of this thesis. It summarized the molecular mechanisms of antitumor activity for the 16 complexes, pointed out the shortcomings in the designed experiments, and put forward the direction of the experimental research in the later days.