Study Of Effects And Mechanism Of Targeted Drug-Loaded FA-Pluronic-PLA Nanoparticles On Ovarian Cancer Cells

Ovarian cancer has been one of the most seriously life-threatening malignant cancers in female with high morbidity and mortality.The number of ovarian cancer patients and deaths are increasing year by year in China.At present,the methods of ovarian cancer treatment is still based on surgical treatment and chemotherapy.However,the application of chemotherapeutic drugs is limited because of its non-selectivity and severe side effects.Targeted drug nanocarrier is one of the hottest point in the research of new anticancer drugs because of its excellent tissue specificity and low side effect.Previous researches generally focused on the synthesis of several amphiphilic block copolymers(PLA-P85-PLA,PLA-F127-PLA and PLA-F87-PLA)and folic acid modified amphiphilic block copolymers(FA-P85-PLA,FA-F127-PLA and FA-F87-PLA)as delivery vectors.In this study,we focus on the cytocompatibility of amphiphilic block copolymers nanoparticles and antitumor effects of FA-Pluronic-PLA loaded with Paclitaxel(PTX)in vitro.1.The cytocompatibility of FA-Pluronic-PLA nanoparticles: Dialysis method in water was applied to prepare PLA-P85-PLA,FA-P85-PLA,PLA-F127-PLA、FA-F127-PLA、PLA-F87-PLA and FA-F87-PLAnanoparticles.The diameter of the nanoparticles determined by dynamic light scattering(DLS)technique,the particle size ranged from 60 nm to 80 nm with a uniform polydispersity index.The morphology of the nanoparticles determined by transmission electron microscope were spherical micelles.The cytocompatibility of PLA-Pluronic-PLA,FA-Pluronic-PLA,and unmodified Pluronic(P85,F127,F87)nanoparticles was analyzed by MTT assay,NRU assay and LDH assay.Our findings suggested that PLA-Pluronic-PLA NPs and FA-Pluronic-PLA NPs have good cytocompatibility,and the modification of FA and PLA can improve the cytocompatibility of Pluronic nanoparticles.The cytocompatibility of FA-F127-PLA nanoparticles was better than others,so we chose it as drug carrier.2.Antitumor efficacy in vitro: The targeting antitumor behavior of FA-F127-PLA loaded with PTX nanoparticles was studied on OVCAR-3 cell line with over expression of Folate receptor(FR)by cytotoxicity assay,AO staining,western blotting.The results showed that FA-F127-PLA/PTX had stronger inhibitory effect on OVCAR-3 cells than nontargeted PLA-F127-PLA/PTX nanoparticles and PTX only in time-and dosage-dependent manner.And FA-F127-PLA/PTX could significantly induce OVCAR-3 cells apoptosis.Furthermore,FA-F127-PLA/PTX induced significantly the expression of p53 protein and reduced the expression of Bcl-2 protein in OVCAR-3 cells.The results above suggested that FA-F127-PLA nanoparticles can target the OVCAR-3 cells which overexpressing FR,and can enhance PTX to move into OVCAR-3 cells more effectively,thereby improving the antitumor efficacy of PTX and,also,that FA-F127-PLA / PTX can kill cancer cells by enhancing the induction of apoptosis through change the expression of apoptosis-related target proteins.In conclusion,FA-F127-PLA nanoparticles may be used as targeted delivery vectors for hydrophobic chemotherapeutic drug,paclitaxel.