Preparation Of Sorafenib Nanoparticles Targeting To Liver Tumor And Evaluation Their Anti-Hepatic Cancer Activity

Sorafenib(SRF)is a multi-target tyrosine kinase inhibitor with a dual anti-tumor effects.However,the progression-free survival of patients on sorafenib is only 167 days,the therapeutic effect is not satisfactory.Lack of tumor targeting is one of the important reasons for the poor efficacy.Nanotechnology provides a feasible strategy to solve this problem:The tumor targeting of drugs can be improved by preparing a nano-drug delivery system.Accordingly,we first designed the human serum albumin-sorafenib nanoparticles(HSA-SRF-NPs)and the folic acid-human serum albumin-sorafenib nanoparticles(FA-HSA-SRF-NPs),and the properties of the two nanoparticles were characterized.The results showed that the hydration particle sizes of the two nanoparticles were 75.8±2.6 nm and 85.4±3.3 nm,respectively,and both of them were less than 100 nm.It is beneficial for nanoparticles to escape the phagocytosis by the reticuloendothelial system(RES),and can reach the tumor site and actively transport into tumor cells.We performed a quantitative and qualitative analysis of folic acid on FA-HSA-SRF-NPs.The results showed that folic acid covalently binds to the surface of the nanoparticles with a high grafting rate.After 6 months,about 81.4%of folic acid was still present on albumin nanoparticles with less shedding.The content of sorafenib in the two nanoparticles was determined by high performance liquid chromatography(HPLC),and the encapsulation efficiency was 92.52 ± 2.40%and 91.09 ±6.14%respectively,in accordance with the requirements of the pharmacopoeia.In vitro release results indicate that the two nanoparticles have sustained release characteristics.Then,in vitro experiments were performed using human liver cancer BEL-7402 cells and HepG2 cells.Results about the accumulation of two nanoparticles in BEL-7402 cells showed that coating sorafenib with HSA significantly increased the amount of sorafenib entering into BEL-7402 cells,and more nanoparticles entered into BEL-7402 cells after grafting folic acid.Although HSA-SRF-NPs uptake in HepG2 cells did not increase significantly,FA-HSA-SRF-NPs uptake was significantly higher than sorafenib.The results of cytotoxicity experiments and plate cloning experiments demonstrated that FA-HSA-SRF-NPs could increase the toxicity of sorafenib to liver cancer cells,while reducing its toxicity to normal hepatocytes.Apoptosis and Western blot experiments demonstrated that FA-HSA-SRF-NPs could further enhance the proapoptotic effect of sorafenib on liver cancer cells.Furthermore,in vivo experiments were conducted to examine the pharmacodynamics,safety,pharmacokinetics and tissue distribution of the two nanoparticles,and to investigate the molecular mechanism of the two nanoparticles to improve the antitumor effect.The results showed that the inhibition effect of FA-HSA-SRF-NPs on tumor gro-wth was significantly stronger than that of HSA-SRF-NPs and sorafenib.Meanwhile,the two nanoparticles did not increase the toxicity of the drug.The retention time of the drug in vivo was significantly prolonged,and the area under the curve of sorafenib was increased after preparing nanoparticles.Among three groups,the distribution of drugs in the heart,liver,spleen,lung and kidney was not statistically different,but the accumulation of FA-HSA-SRF-NPs in tumor site increased significantly,indicating that FA-HSA-SRF-NPs had tumor active targeting effect on xenografts.FA-HSA-SRF-NPs significantly increased inhibition of tumor proliferation and angiogenesis,activation of apoptotic pathways and blocking of RAF/MEK/ERK pathways.To sum up,the prepared FA-HSA-SRF-NPs had high encapsulation efficiency,good stability and sustained release,and had obvious active targeting to the two liver tumor cells expressing folic acid receptors.The activity of anti-liver tumor in vitro and in vivo was significantly better than that of sorafenib,which has potential clinical research value.