The Study On The Synthesis And Antitumor Activity Of New Iridium(?) Complexes And Their Long-circulating Liposomes Preparations

Due to the rapid economic development,people's living standards have greatly been improved,but a lot of problems were arosen.Concerning about the current medical challenges,treatment of malignant tumors is a hot spot.The therapy of tumors can be displayed as chemotherapy,radiotherapy and surgery.Comprehensively considering the conditions in various aspects,chemotherapy priors to others,and metal antitumor drug cisplatin appears in clinical applications with its effective therapy.However,some water-soluble,toxic side effects,and poor selectivity have emerged with the improvement of treatment.Scientists began to explore new anti-cancer drugs and turned their attention to iridium metal complexes as new anti-neoplastic drugs.In this dissertation,five antimony complexes were synthesized,among which three of them have poor water solubility,they cannot enter into the cells through cell membranes,so they have no anti-tumor activity.In order to overcome the shortcomings of poor water solubility,we changed the formulation of the drug to prepare a Iridium???complex liposome with good water solubility and long cycle characteristics,which laid the foundation for subsequent anti-tumor biological activity experiments.In this study,we explore the antitumor activity of drugs both in vitro and in vivo.In vitro experiments,we first performed a preliminary screening of the antitumor activity of the complexes using MTT assay and found that these complexes have good effect on specific cells.Afterwards,we found that the morphology of the cells changed and the nucleus was pyknosis after dyed with AO/EB for complexes and liposomes.Flow cytometry to quantify was used the cell cycle and the percentage of apoptosis,it was found that the cells were arrested in a certain phase,resulting in a large proportion of cells undergo apoptosis.Single-cell gel electrophoresis was used to analyze the extent of damage to DNA for the complexes and liposomes,which found that complexes and liposomes caused DNA tailing,indicating that the DNA was broken.Changes in levels of reactive oxygen species,changes in mitochondrial membrane potential,Ca²⁺,and autophagy in the cells were assessed using fluorescence microscopy or flow cytometry or high-content cell imagers.The results showed that increased levels of reactive oxygen species,decreased mitochondrial membrane potential,increased Ca²⁺content,and induced autophagy occurred.The cytochrome c content was also detected by immunofluorescence.The cytochrome c content was also detected by immunofluorescence.As a result,the cytochrome c was released from the mitochondria to the cytoplasm due to the disruption of the mitochondrial membrane which due to the complex.Finally,we investigated the apoptotic pathway of cells through Western blotting experiments.We found that these complexes and liposomes increased the expression of the pro-apoptotic proteins of the Bcl-2 family,reduced the expression of anti-apoptotic proteins,and activated the expression of the Caspase family proteins,which leads to cell apoptosis.These results indicate that these Iridium complexes and liposomes induce apoptosis through ROS-mediated mitochondrial apoptosis pathway.We further conducted in vivo experiments on the anti-tumor activity of drugs.We evaluated the in vivo inhibitory effect of drug on tumor growth by xenograft model.The study found that the relative growth rate of the tumor in the administration group became slow,the weight of the tumor was smaller,and the inhibition rate of the tumor was larger compared with the blank group.Therefore,in vivo experiments also confirmed that the drug has anti-tumor activity.