Co-Encapsulation Of Paclitaxel And 2-Methoxyestradiol In Folate-Conjugated Human Serum Albumin Nanoparticles For Improving Antitumor Efficacy

In recent years,cancer is a great threat to human health and survival.There are many ways to cure cancer and some main techniques include surgical treatment,radiotherapy and chemotherapy.However,undoubtedly,chemotherapy drugs are the best choice for cancer treatment in the future,for surgical treatment and radiotherapy will bring great pain to patients.The use of chemotherapeutic drug Paclitaxel?PTX?for the treatment of tumors has several limitations such as multidrug resistance and serious adverse reactions.To overcome these faultiness,the aim of study to develop co-encapsulation of Paclitaxel?PTX?and the chemosensitizer 2-Methoxyestradiol?2-ME?into folate-conjugated human serum albumin nanoparticles?FA-HSANPs?for multiple drug resistance and anti-tumor efficiency.The main contents of this research are divided into the following three aspects:Part ?PTX/2-ME@FA-HSANPs Preparation and Characterization:PTX/2-ME@FA-HSANPs were prepared by desolvation method.The particle size,zeta potential of PTX/2-ME@FA-HSANPs were measured by dynamic light scattering.Transmission electron microscope was used for morphological examination.The encapsulation efficiency,drug loading and drug release profile of PTX /2-ME@FA-HSANPs were determined by using HPLC.PTX/2-ME@FA-HSANPs exhibited spherical morphology,which was uniform with particle size of 180 ± 12.31 nm.The zeta potential was approximately-20 mV.The encapsulation efficiency of PTX was 92.3 ± 0.57% and 2-ME was88.3 ± 0.31% in PTX/2-ME@FA-HSANPs,and the loading efficiency of drugs in PTX/2-ME@FA-HSANPs was 8.3 ± 0.15% and 7.9 ±0.41%.Cumulative release reached almost 85% after two days and showed that the NP formulation was able to release the drug almost completely.Part ? Antitumor activity of PTX/2-ME@FA-HSANPs in vitro: The human esophageal cancer cell line EC109 and its PTX-resistant cells?EC109/Taxol?were used for investigating this part.The in vitro cytotoxicity ofdifferent formulations in EC109 and EC109/Taxol cells was evaluated by MTT assay.The cellular inhibition rate,IC50 values and Resistant index?RI?were calculated.We used fluorescence microscopy and FACS to evaluate the cellular uptake ability.Cell apoptosis and cycle was analyzed by FACS to investigate its anti-tumor mechanism.MTT test results show that the combination of the two drugs can reduce the drug resistance index and increase the killing effect on tumor cells.In addition,compared with other control groups,the targeted agent group PTX/2-ME@FA-HSANPs has the strongest inhibitory effect on tumor cells;PTX/2-ME@HSANPs delivery system could effectively enhance the uptake of drugs into cells.Moreover,PTX/2-ME@FA-HSANPs demonstrated greater ability to transfer the drugs into the cells.PTX/2-ME@FA-HSANPs exhibited optimal effects in inducing cell apoptosis,which further demonstrated that PTX and 2-ME co-encapsulated in FA-HSANPs exhibited enhanced antitumor effects and apoptosis-inducing activities in the G2/M phase through the synergistic effects of simultaneously released PTX and 2-ME.Part ? Pharmacokinetics and in vivo antitumor activity of PTX/2-ME@FA-HSANPs: Female Sprague Dawley rats?180–220 g?were used for studying Pharmacokinetics of PTX/2-ME@FA-HSANPs.S₁80 tumor-bearing mice were used as model animals to investigating antitumor activity of PTX/2-ME@FA-HSANPs.The tumor treatment effect was judged by tumor volume size and HE tissue staining;the safety of the preparation in vivo was evaluated by blood routine examination of mouse appearance,HE tisue staining section,bone marrow suppression and hepatotoxicity.The pharmacokinetic parameters AUC and t_1/2in the PTX/2-ME @FA-HSANP group were around two times that in the PTX+2-ME group,respectively.From the relative tumor volume,the synergistic effect can be achieved after the combination of the two drugs,and the anti-tumor effect is obvious.In the safety evaluation,tumor weight and other indicators proved that the targeted preparation PTX/2-ME@FA-HSANPs was not obvious toxic side effects on the health organs.Therefore,co-encapsulation of PTX and 2-ME in FA-HSANPs could improveantitumor effects and minimize side effects in vivo.Therefore,co-delivery of anticancer drug and a chemosensitizer in nanocarriers might be a promising approach for drug-resistance tumor therapy.