Water-based Ferrofluids Combine With Fusion Proteins RGD-tTF Double Target Tumor Vessels And Induced Thrombosis

It is a promising anti-tumor strategy to selectively induce thrombosis in tumor vessels by using targeted vascular embolization drug.This strategy used truncated Tissue Factor(tTF) as the effector,which combined with tumor vessels targeting carrier to selectively induce thrombosis in tumor vasculature and cut off the nutrition or oxygen supplies of tumor,subsequently resulted in necrosis of the tumor and obtained anti-tumor effects.Current research usually adopted the mode of monomer carrier combined with monomer effector whose curative effect would not be satisfied, owing to the problem of insufficient binding,low loading drug carrier and slow effector targeting enrichment and deficiency concentration.In order to overcome the above problem and improve the anti-tumor effects,using water-basic ferrofluids to prepare a novel targeting vascular embolization nano-sized drug is introduced for the first time in this paper,which have the properties of drug carrier multiple binding; high capacity carried and double targeting.To verify the possibility of this assumption,MnFe₂O₄ was prepared by improved chemical coprecipitation,used FeCl₃·6H₂O as iron sources and NaOH as alkali.Acetic acid and citric acid was used to modify the property of MnFe₂O₄ in the process of preparation.The diameters of MnFe₂O₄ were measured under H-600 electron microscope.Magnetic property was identified by SQUID.MTT and LDH colorimetric assay were used to test its cytotoxicity.Series of experiments in vitro were used to test the activity of RGD-tTF-MnFe₂O₄.The targeted location and tumor vascular embolization effect of RGD-tTF-MnFe₂O₄ was tested in tumor-bearing mouse models.The results showed that the synthesized nanoparticle were round or ellipse,whose diameter was about 10-25 nm.This water-basic ferrofluids exhibits apparent the superparamagnetism and magnetic fluxional phenomenon,which can be stably preserved.Procoagulation activity test and activating factorâ…©properties test showed that the ability to activate Fâ…©and induce blood coagulation was preserved after RGD-tTF fusion protein combined with ferrofluids,while the binding rate with endothelial cells had no significant effect.Water-basic ferrofluids can also induce RGD-tTF to localize cell in vitro in a magnetic field.In the H22(mouse liver cancer)-bearing mouse models,the selective localization was observed both in RGD-tTF-MnFe₂O₄ group and RGD-tTF group in histological studies.Blood vessels of the tumors in the treated groups were thrombosed and occluded,which induced tumor necrosis,while no thrombosis and cell necrosis was observed in normal tissues. Besides,with the effect of magnetic fields the localization of RGD-tTF-MnFe₂O₄ in tumor tissues and thrombosis degree was all better than treated with RGD-tTF alone.In summary,RGD-tTF water-basic ferrofluids was successfully prepared by nanotechnology,which has both biological and physical targeting.It could selectively and effectively induce thrombosis in tumor blood vessels,inhibit the growth of tumor, and lead to the necrosis of tumor tissues.These results testified that the combination of water-basic ferrofluids and RGD-tTF can implement the double targeting therapy of selective thrombosis in tumor blood vessels.