Codelivery Of Curcumin And Cisplation Based On ZIF-8 Nanosystem For Esophageal Squamous Carcinoma Treatment In Vitro And In Vivo

Cancer is one of the major causes of human death in the world,among which,esophageal cancer is the eighth most common gastrointestinal malignancy in the world.Esophageal cancer ranks seventh in terms of incidence and sixth in mortality overall among all cancers.Although people have spent a lot of efforts to explore the treatments of esophageal cancer,such as endoscopic therapy,chemotherapy,surgical therapy,and the newly developed molecular targeted therapy and immunotherapy in recent years,the prognosis of esophageal cancer has not been significantly improved,so it is urgent to explore new and effective methods for the treatment of esophageal cancer.Cisplatin(CDDP)is the main chemotherapeutic agent in the first-line treatment of esophageal cancer.However,the dose-limiting side effects and the resistance of cisplatin reduce the clinical therapeutic effect and make the antitumor effect unsatisfactory.Fortunately,curcumin(Cur)-mediated glutathione depletion can reverse cisplatin resistance,enhance the chemical sensitivity of cisplatin,and further improve the effect of chemotherapy for esophageal cancer.However,the poor water solubility and low bioavailability in vivo restrict the application in clinic.In recent decades,with the rapid development of nanotechnology,nano drugs become popular in the research of pharmaceutical preparations.Compared with the traditional way of drug loading,nanoparticle can improve drug solubility and stability,enhance drug targeting and extend biologic half life of drug etc,thus possessing great advantages in the biomedical field and showing a broad application prospect.Metal-organic frameworks(MOFs)have become excellent candidate vectors for the construction of nanomedicines due to their adjustable chemical composition,highly ordered porous structures,high specific surface area,functional diversity and good biological stability.Therefore,in this paper,the most representative Zeolitic imidazole-8(ZIF-8)was used as the drug carrier to carry cisplatin and curcumin,in order to solve the above drawbacks at the same time to achieve multi-mode treatment of esophageal cancer.The specific content is as follows:1.We developed Cu-doped ZIF-8 nanomaterials(Cu/ZIF8)for loading chemotherapeutic drugs CDDP and Cur.The ultra-small gold nanoparticles(Au nanoparticles)were modified on the surface of Cu/ZIF8 by the method of surface reduction to synthesize Cur/CDDP@Cu/ZIF8@Au therapeutic nanocomposites.The particle size of the nanocomposite was about 145 nm.In this system,Cu/ZIF8 can not only be used as drug carrier to load CDDP and Cur(loading efficiency was 11.4%),but also induce Fenton-like reaction to generate hydroxyl radical(·OH)to kill tumor cells after reduction by intracellular glutathione(GSH).Au nanoparticles can act as GOx-minic.By catalyzing glucose in tumor cells,the content of hydrogen peroxide(H2O2)in cells is increased,so as to improve the production speed of Cu+-indecued Fenton like reaction,realize cascade catalysis,and improve the tumor inhibition rate of chemical kinetics(CDT).Cu/ZIF8 can release Cur and CDDP in acidic environment(the cumulative release rate of Cur was 27%in acidic environment at pH5.6 for 48 h).Cur-mediated GSH consumption can enhance the sensitivity and bioavailability of CDDP,and thus improve the antitumor efficiency.2.Using Eca-109 cells and tumor-bearing mice as models,we studied the antitumor effects of the Cur/CDDP@Cu/ZIF8@Au nanocomposites synthesized in our previous step in vitro and in vivo.The uptake of nanoparticles by Eca-109 cells and the intracellular production of reactive oxygen species(ROS)by nanoparticles were observed by confocal microscopy and analyzed by flow cytometry.CCK-8 assay,apoptosis test and Western blot analysis of apoptotic proteins were used to investigate the killing effect of nanoparticles on tumor cells.The antitumor effect of nanoparticles in vivo was studied by intravenous injection of nanocomposite in mice bearing Eca-109 tumor cells.The results showed that when the concentration of nanoparticles was 40μg/mL,the cell uptake rate reached 86.1%in 6 hours.A large number of ROS were found in Eca-109 cells co-incubated with Cur/CDDP@Cu/ZIF8@Au.When the concentration of nanoparticles was 40 μg/mL,cell survival rate is only 7.6%,and the apoptosis rate was as high as 45.3%,at the same time,the expression of Bcl-2(antiapoptotic protein)was downregulated and the expression of Caspase-3(apoptotic executive protein)and Bax(proapoptotic protein)was upregulated.Transportation of Cur and CDDP via Cur/CDDP@Cu/ZIF8@Au nanocomposites can sensitize CDDP,enhance its bioavailability.Enhanced chemotherapy in combination with chemodynamic therapy ultimately inhibits the proliferation of tumor cells.Cur/CDDP@Cu/ZIF8@Au nanoparticles could accumulate efficiently in Eca-109 tumor-bearing mice,thus improving the targeted utilization of drugs.After 12 days of treatment,the tumor weight was reduced by 87 times(compared with normal saline control group),and the expression of Bcl-2 was downregulated and the expression of Bax,Caspase-3,γ-H2AX(DNA damage protein),and PARP enzyme were upregulated.Nanoparticles did not cause major organ lesions and systemic side effects in mice during the whole treatment process.In conclusion,the nanosystems showed good tumor inhibition in vitro and in vivo with high biosecurity.This work provides an idea for the safe treatment of esophageal cancer using multifunctional nanotherapy platform.