Design And Application Of Ratio-type CO Light-controlled Release Agent And Carbonic Anhydrase IX Prodrug

Carbon monoxide(CO)is a toxic gas without colour and taste.It readily binds with hemoglobin to produce carboxyhemoglobin,which weakens the ability of hemoglobin to transport oxygen.Therefore,excessive inhalation of CO can lead to death.Moreover,excessive CO is toxic to almost all kinds of cells,especially the cerebral cortex,so CO has been considered as a toxic gas harmful to human body.In recent years,it has been found that CO,as an important gas signal molecule and neurotransmitter,is widely involved in the regulation of nerve,cardiovascular,endocrine and immune system.Therefore,the effective delivery of CO in organisms has attracted wide attention.Carbonic anhydrase IX(CAIX),as a zinc-containing metalloproteinase widely existing in organisms,can regulate intracellular p H and increase the ability of cancer cells to tolerate hypoxia,which is closely related to the proliferation and metastasis of cancer cells.Under hypoxia,cancer cells trigger hypoxia-inducible factor-mediated signal cascade reaction,and up-regulation of CAIX gene is triggered by transcription of angiogenesis factor.All these make CAIX abundantly expressed in hypoxic tumors,thus mediating cancer recurrence.Therefore,as a cancer marker and a target of anticancer prodrugs,CAIX has received a certain degree of attention.In view of the important physiological and pathological roles of CO and CAIX,two small molecule fluorescent compounds,PFN and CNN,have been designed and synthesized.The mechanism of light-controlled release of CO by PFN and CAIX-inhibition based anti-cancer effect of CSN was studied.Moreover,their preliminary applications were performed.The specific research contents are as follows:(1)Hydrogen sulfide-activated CO photo-releasing agent PFN was prepared by linking photosensitive compound of flavonol and pyrene as fluorescent parent,as well as dinitrophenyl ether as the H2S-responsive group.The ratiometric fluorescence response to H2 S was achieved with PFN.Moreover,this "H2S activated" molecule released the gas signal molecule CO under illumination.Based on this,a cell model of colitis was constructed.The response of the probe to endogenous H2 S and the photocontrolled release of CO in cells were investigated.It was found that the release of CO could effectively reduce the levels of inflammatory cytokines such as TNF-alpha and IL-6,which could potentially alleviate or treat colitis.This study further expands the types of CO photo-controlled release agents and provides an effective analytical method for studying the physiological and pathological functions of CO.(2)Sulfonamide group based carbonic anhydrase IX inhibitory prodrug CSN was prepared.The prodrug targets the overexpressed carbonic anhydrase IX in breast cancer cells through the carbonic anhydrase IX inhibitor group,and releases the antineoplastic drug nitrogen mustard under hypoxic conditions,in order to achieve the dual killing effect on cancer cells.Inhibitory effect of CSN on breast cancer cells was preliminarily investigated,and the effect was good.The results provide a new method for the study of anticancer prodrugs based on tumor migration and transformation related enzyme inhibitors.