Synthesis And Anticancer Properties Of Multiorganelle Targeted Type Ⅰ Photosensitizer

Cancer has become a serious threat to human health.Surgery,chemotherapy and radiotherapy are the most usually used cancer therapeutic methods,but these methods are more or less seriously inadequate.Photodynamic therapy（PDT）has gained widely attention and rapidly development due to the advantages of non-invasive,small side effects,low drug resistance and elimination of recessive lesions.According to the photodynamic mechanism,PDT can be divided into two types:Type Ⅰ and Type Ⅱ.Currently,most PSs were through Type Ⅱ mechanism which heavily relied on aerobic conditions to perform the treatment.However,hypoxia in tumor microenvironment can lower the efficiency of type Ⅱ PDT,while the advantage of oxygen production in electron transfer reaction through type I PDT can effectively solve the problem of mionectic tumor.Type Ⅰ PSs dependence solve the problem of traditional PSs of mionectic tumor.Nevertheless,seldom tumor targeting type I PSs have been reported,and only a handful of type I PSs have been developed through targeted composite material or modified with specific target groups to improve the tumor selective.Furthermore,there was only one targeted organelle for those type I PSs,it is quite difficult to achieve coordinated precision therapy through one PS with multiple targets.Therefore,this thesis aims to design and synthesize type I PSs with multi-organelle targeting for selective photodynamic anticancer research.Specific research results are described as follows:1.Synthesis and photophysical property of thiophene acrylonitrile photosensitizer:Using thiophene acrylonitrile as the skeleton,the fluorophore was constructed with push-pull electron system in order to establish the regulation of type Ⅱ to type I PSs system,in which the electron donor groups with different ring tension were modified.A series of 6 liposoluble cationic PSs with D-A structure were synthesized.The chemical structures of these PSs were characterized by ¹H NMR,¹³C NMR and high resolution mass spectrometry.The photophysical properties of PSs were studied by ultraviolet-visable spectrophotometer and fluorescence spectrometer.With the changes of the ring tension from the electron-donating group,no obvious absorption and emission change was observed.However,the decrease of ring tension can effectively improve the production performance of reactive oxygen species and hydroxyl radicals,and reduce the production efficiency of singlet oxygen,which can help us regulate the PSs from type Ⅱ to type I through changing the ring tension.Among them,ACR-DME has the best production performance of reactive oxygen species and hydroxyl radical.2.Selective photodynamic anticancer studies based on thiophene acrylonitrile photosensitizers:The cancer cells selectivity of the thiophene acrylonitrile fluorescent probes was investigated through fluorescence imaging experimental.ACR-DME and ACR-CBNBO could selectively enter into cancer cells,while other PSs did not have any selectivity for cancer cells.The co-localization analysis of the organelle targeting of the probes showed that ACR-CBNBO,ACR-CBN,ACR-CPN,ACR-CHN and ACR-DME were enriched in the cell membrane,mitochondria and nucleus simultaneously,while ACR-TPA was only enriched in mitochondria.CCK8 assay was used to investigate the cytotoxicity of the probes in vitro.All probes had good biocompatibility.ACR-CBNBO can selectively enter cancer cells and has no any phototoxicity.ACR-CBN,ACR-CPN,ACR-CHN and ACR-TPA have certain phototoxicity to all kinds of cells.ACR-DME has excellent phototoxicity to cancer cells and no phototoxicity to non-cancer cells,so it can be used for selective photodynamic therapy of cancers.Confocal laser imaging showed that ACR-DME could effectively produce type I ROS in cells,i.e.^·OH,and had no significant effect on cell survival under normoxic and hypoxic conditions,indicating that ACR-DME could effectively combat with hypoxic conditions of tumor and has excellent potential for photodynamic therapy of tumor.3.In vivo imaging and antitumor activity of thiophene acrylonitrile PSs:4T1tumor-bearing mice were established for in vivo imaging and photodynamic therapy.In vivo imaging showed that ACR-DME was mainly distributed at the tumor site after 4 h intravenous injection.Under white light irradiation,ACR-DME could significantly inhibit the solid tumor growth and the therapeutic effect was better than that of commercial PS Ce6.The anti-tumor ability of ACR-DME was verified by immunohistochemical analysis of H&E and Ki67 pathological methods.In addition,ACR-DME has good biocompatibility and has no any toxicity and side effects on mice.