Studies On The Antitumor Activity Of Cordycepin And Its Transferrin Targeted Liposomes

Background / Objective: cancer has always been the biggest killer of human health.Liver cancer is the third most common malignant tumor after gastric cancer and esophageal cancer.Surgical resection,liver transplantation and radiotherapy and chemotherapy are used in the clinic.However the recovery rate is lower in advanced patients because of the proliferation of cancer cells.There is about 110 thousand people in China died of liver cancer ever year,accounting for 45% of the world's total deaths.Breast cancer is one of the most common cancer in women.There are still a lot of women suffering from breast cancer in the world,despite the growing technology.According to statistics,about 400 thousand cases of women die from breast cancer worldwide every year.Therefore,early detection,early diagnosis and early treatment of cancer should be done.Cordycepin(cordycepin),also known as cordycepin,cordycepin and so on,is the main active ingredient in Cordyceps sinensis,an endogenous nucleoside.It has many pharmacological functions such as anti-tumor,anti-virus,anti-aging,antibacterial,immunological regulation and scavenging oxygen free radicals.Although the cordycepin shows good prospects for clinical application,however it is easy to find that drugs after reaching the lesion have low absorption rate and poor solubility,direct drug effect of poor.The purpose of this study is to develop an effective targeting liposome drug delivery system to enhance the solubility and biological activity of cordycepin and to evaluate the drug delivery system in vivo and in vitro.This research mainly includes the following aspects:1.Evaluation of anti hepatoma and anti breast cancer activity of cordycepinThe apoptosis of cancer cells has been widely concerned,studies have shown that mitochondria is the core parts of apoptosis,which can be used as an effective target for cancer treatment,when the decline of mitochondrial membrane potential will then start MAPKs and AKT signaling pathways in cell apoptosis by regulating m TOR protein dependent Caspase activity and inhibit tumor growth.By using PLC/PRF/5 and Hep G2 hepatocellular carcinoma cells and breast cancer cells MCF-7 and MDA-MB-231 cells model respectively on cell viability,cell proliferation,LDH activity and the level of reactive oxygen species,determine the change of mitochondrial membrane potential and apoptosis related protein content analysis and a series of experiments in vitro,and in vivo experiment in nude mice,the dosage is 30 mg the cordycepin medication for two weeks.Results showed that cordycepin could induce apoptosis of hepatocellular carcinoma cells and breast cancer cells,cancer cells promote the accumulation of ROS,leading to mitochondrial apoptosis related protein content changes,and after administration of the tumor volume decreased significantly.Therefore,both in vivo and in vitro experiments confirmed the anticancer effect of cordycepin and determined the medicinal safety of cordycepin2.Preparation of cordycepin liposome and characterization preliminary metabolism in vivoLiposome is an effective carrier with good biocompatibility,commonly used to targeted transport drug,improve the therapeutic effect,and reduce the toxic side effects of sensitiveorgans.The standard curve of cordycepin was established by HPLC method of cordycepin in cordycepin liposomes in vitro.The linearity was good in the range of 0.1-200ug/ml,R2 reached 1 and the entrapment efficiency was 65.3%.Metho-dological study found that its precision,stability are good.In order to increase its practical application value,we have established a polyethylene glycol lipid intermediate layer and multilayer lipid nanoparticles targeting the outer layer ofthe ligand,Mainly through the transferrin modified lipo-somes and contain a new drug-carried system containingcordycepin.And the determination of particle size and pote-ntial of cordycepin,liposome and transferrin-modified lipos-omes.The results showed that the size of the transferrin-modified liposome was 125 nm,which was slightly larger than that of the liposome 91 nm.The transferrin-modified liposome potential was 2.9 m V,which was smaller than that of the liposomes 9.2m V,with significant differences.And also through the liposome,transferrin liposome in vitro test,both showed liposomes and transferrin liposomes have a better release rate,transferrin liposome than liposomes The cytotoxicity is stronger,the intake is high,the ability to induce apoptosis is more remarkable.3.Evaluation of Antagonistic Activity of Cordycepin Liposomes and Transferrin Liposomes against Liver Cancer and Breast CancerUsing hepatoma cell lines(Hep G2 and PLC/PRF/5)and breast cancer cell lines(MCF-7 and MDA-MB-231)to investigate the antitumor effects and related mechanisms of LPs and Tf-LPs two different drug delivery systems in vitro and in vivo.The cell inhibition test,ROS assay and mitochondrial membrane potential detection,Western blot,cellular uptake pathways of LPs and Tf-LPs drug delivery systems were tested for antitumor activity analysis,and study on the anti-tumor effect of mouse liver cancer model and breast cancer model in vivo.In vitro evaluation showed that the IC50 values of hepatoma cell lines(Hep G2 and PLC / PRF / 5)and breast cancer cell line(MCF-7 and MDA-MB-231)via the Tf-LPscordycepin drug group was significantly lower than other administration group,and the transfection efficiency of Tf-LPs-Cordycepin was also better than that of LPs-cordycepin group by flow cytometry.Inhibitors were added to facilitate the study of drug uptake,and found that it is a transferrin-mediated endocytosis pathway into the tumor cells and take effect.Due to the accumulation of intracellular reactive oxygen species will make mitochondrial membrane potential changes,and cause apoptosis.Tf-LPs significantly increased intracellular ROS production and induced mitochondrial membrane potential depolarization.Western blot analysis showed that the expression of pro-apoptotic protein was significantly increased by Tf-LPs,and the anti-apoptotic protein content was decreased.This suggests that Tf-LPs-Cordyceps can inhibit cell proliferation in both tumor cell lines and induce apoptosis of cancer cells through ROS-associated mitochondrial pathways.In vivo evaluation results show that Hep G2 and PLC/PRF/5 hepatoma model and MCF-7 and MDA-MB-231 in ectopic ectopic breast cancer model after 14 days after treatment,the changes of body weight of nude mice was not obvious,while the Tf-LPs-cordycepin group tumor volume decreased significantly,indicating that Tf-LPs can carry more drugs into cells exert antitumor effects.Therefore,the stability and security of the investigation in the preparation process and method of liposome and study its antitumor activity in vitro and in vivo.The results show that transferrin-conjugated liposomes are effective as nanocarriers for cordycepin delivery to cancer cells.To provide a theoretical basis for the new preparation of cancer targeted therapy.