Preparation Of 5-Fluorouracil-Loaded Poly(D,L-lactide-co-glycolide) Nanoparticles And Its Inhibitory Effect On Proliferation Of Huh7 Hepatocarcinoma Cell In Vitro

Chemothrapy is one of the methods commonly used in treating liver cancer,however,the chemotherapy drugs are often short of selectivity and thus produce toxic side effects on the body, which limit the widespread application of chemotherapy. At present, as a new targeting drug delivery system, drug-loaded nanoparticle system has great potential for development in the field of drug delivery systems. It is a new product produced by nanotechnology combined with modern medicine. Drug-loaded nanoparticles can enhance the efficacy of drugs and reduce toxic side effects by changing the distribution of drugs in the body and process of the pharmacokinetics, enhancing drug accumulation in the targeted areas at a higher concentration, and controlling drug release effectively. Especially in the field of treatment of cancer, drug-loaded nanoparticle system has broad prospects in application. This study is aimed to prepare 5-fluorouracil(5-FU) loaded nanoparticles and expected to provide a new way to treat liver cancer in the future.【Objective】Using the poly(D,L-lactide-co-glycolide)(PLGA) as a carrier, this study was carried out to construct 5-FU loaded nanoparticles(5-FU-PLGA) and to investigate its inhibitory effect on proliferation of Huh7 hepatocarcinoma cell in vitro.【Methods】The 5-FU-PLGA nanoparticles were prepared by double emulsification solvent evaporation technique. The morphology and particle size distribution of nanoparticles were determined by field emission scanning electron microscope and laser particle size analyzer, respectively, and the granulation rate of nanoparticles was calculated. The drug loading, encapsulation efficiency of 5-FU and release in vitro were detected by ultraviolet spectrophotometer. Huh7 cells were co-cultured with nanoparticles for 24 hours and then the celluar uptake of nanoparticles was evaluated by fluorescence microcopy and transmission electronic microscopy. The cell viability was detected by MTT assay when Huh7 cells were co-cultured with different concentration of 5-FU-PLGA nanoparticles or naked 5-FU for 24 hours, 48 hours, 72 hours, 96 hours, 120 hours, 144 hours, respectively. Cell apoptosis was analyzed by flow cytometry.【Results】The nanoparticles were spherical in shape with average diameter (186±14) nm. The granulation rate, drug loading and encapsulation efficiency were 70.8%, 6.6% and 28.1%, respectively. The 5-FU-PLGA nanoparticles showed slow release character in vitro. The cumulative release of 5-FU was 83.6% at the 10th day. The celluar uptake of nanoparticles was observed by fluorescence microcopy and transmission electronic microscopy. The MTT assay showed that cell viability decreased in naked 5-FU and 5-FU-PLGA group with time (P<0.001). The cell viability in 5-FU-PLGA group was significantly lower than that in naked 5-FU group at the same time point (P<0.001), and 20μg/mL 5-FU-PLGA group had the strongest effect on inhibition of cell proliferation with cell viability of (20.3±1.25)% after 144 hours. Cell apoptosis rate was detected at the end of 144 hours induced by 5-FU and 5-FU-PLGA nanoparticles. Cell apoptosis in 5-FU-PLGA group was significantly higher than that in naked 5-FU group (P<0.001), especially in 20μg/mL 5-FU-PLGA group with cell apoptosis rate of (81.0±3.8)% .【Conclusion】The 5-FU-PLGA nanoparticles are prepared successfully and have slow release function in vitro. 5-FU-PLGA nanoparticles can be internalizated by Huh7 cell and provide a slow and sustained release of 5-FU in the cytoplasm. The inhibitory effect on proliferation of Huh7 cell of 5-FU-PLGA nanoparticles is better than that of naked 5-FU, especillay at the concentration of 20μg/mL. 5-FU-PLGA nanoparticles are expected to be a new targeting drug delivey system for treatment of liver cancer.