Synthesis And Antitumor Activity Of Theranostic Prodrug Activated By Hypoxia And Mediated By Indomethacin

Chemotherapy is the main means of cancer treatment and traditional chemotherapy drugs have serious toxic side effects and drug resistance in clinical applications.FDU is an anti-metabolism and anti-tumor drug that can be used for the treatment of colon cancer,rectal cancer,liver cancer,and gastric cancer.However,FDU can cause toxic effects on normal tissues and bring about some adverse consequences.Therefore,it's imperative to develop anti-tumor prodrugs with better therapeutic effects and less side effects.Small-molecule theranostic prodrugs for tumors with the diagnosis,treatment and evaluation can realize the monitoring of drug-specific release and release of drugs in the tumor area.The feedback of relevant information in the tumor tissue can evaluate the therapeutic effect and guide the next treatment.Hypoxia is one of the most important features of solid tumors.The tumor's hypoxic microenvironment can lead to enhanced tumor cell tolerance and treatment failure.However,the hypoxic microenvironment of tumors has also opened up new avenues for the treatment of cancer by utilizing the unique microenvironment of hypoxic tumor tissue to activate hypoxic-responsive antitumor prodrugs.It can be caused specific release in hypoxic regions of tumors and reduces toxic effects on normal tissues.Indomethacin?IMC?is a commercially available and anti-inflammatory of non-steroidal drug?NSAID?,which has analgesic,anti-inflammatory and antipyretic effects.It is mainly used to treat acute and chronic rheumatism,such as arthritis,gouty arthritis,ankylosing spondylitis,and cancerous pain.It has been reported that IMC can be used as a targeting group to be recognized by over-expressed COX-2 in tumor cell.In addition IMC increase the accumulation of IMC conjugated drugs in the lesion site.In order to reduce the toxic effects of chemotherapeutic drugs in the course of cancer treatment,and to monitor the release of the drug in the lesion and the therapeutic effect in real time we start our study.In our study,FDU is used as an active drug model,and IMC is used as atargetinggrouptotargetCOX-2overexpressedbytumorcells.2-Carboxy-2'-hydroxybiphenyl is used as a fluorescent dye precursor and p-nitrobenzyl is Hypoxia-activated groups.Based on the study we designed and synthesized hypoxic activated anti-tumor prodrug IMC-FDU-YNB-NO₂.We characterized prodrugs and intermediates by NMR,MS and other means.Fluorescence spectroscopy was used to investigate the effect of hypoxic incubation time on drug release and the stability and selectivity of the prodrug.MTT assay was used to determine the cell viability of IMC-FDU-YNB-NO₂ co-incubated with HepG-2 and BRL-3A under different oxygen levels.Cellular hypoxia and drug release were detected by confocal fluorescence imaging,and the ability of IMC to target tumor cells was evaluated according to intracellular fluorescence signal intensity.BALB/c Nude mice were used to establish HepG-2 xenograft mouse models.The tumor volume and body weight were measured by tail vein injection of IMC-FDU-YNB-NO₂?10 mg/Kg?to evaluate its antitumor activity in vivo.Pathological analysis of mouse tumors and various organs using HE and TUNEL staining.The results show that IMC-FDU-YNB-NO₂ has hypoxic selectivity and IMC-FDU-YNB-NO₂ can releases FDU,IMC-TZBCM under hypoxic conditions.As the incubation time increases,the drug release increases,and the fluorescence intensity of IMC-TZBCM is proportional to the release of FDU.IMC-FDU-YNB-NO₂ is toxic to HepG-2cells and dose-dependent under hypoxic conditions.Under the mediation of IMC,cells increase the uptake of IMC-FDU-YNB-NO₂ and the released IMC-TZBCM can be used for the detection of cellular hypoxia.MC-FDU-YNB-NO₂ exhibited good anti-tumor activity in tumor-bearing mice.The tumor inhibition rate was 82.7%,and IMC-FDU-YNB-NO₂ had no toxic effects on various organs.The constructed IMC-FDU-YNB-NO₂ has the dual functions of diagnosis and treatment.After targeted delivery of drugs to the tumor area,the IMC-FDU-YNB-NO₂ uses the hypoxia activation strategy to achieve the precise release of drugs in the tumor region,reduces the toxic and side effects of FDU,and provides a new method of detection and treatment in hypoxic tumors.