Background: Extreme hydrophobicity and poor stability of SN-38, a highly potent topoisomerase I inhibitor, has prevented its clinical use. Its encapsulation into nanoparticles may be a way to overcome these problems. Here we report the use of SN-38-loaded hyaluronic acid (HA)-decorated poly(lactic-co-glycolic acid)-polyethylene glycol (PLGA-PEG) nanoparticles (NPs) for targeted ovarian cancer therapy.
Materials and methods: PLGA-PEG nanoparticles loaded with SN-38 were prepared by single- emulsion (O/W) solvent evaporation method. HA was decorated onto the nanoparticles by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) coupling and the extent of HA conjugation was quantified by hexadecyltrimmethylammonium bromide (CTAB) assay. Cancer cell specificity of the NPs was determined by flow cytometry and cytotoxicity of the NPs was tested by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium (MTT) bromide assay.
Results: Mean size, zeta potential and encapsulation efficiency of PLGA-PEG-HA NPs were 265.6 ± 3.8 nm, -30.4 ± 0.1 mV and 75.8 ± 4.1%, respectively. Cellular uptake of PLGA-PEG-HA NPs was 8- and 16-fold higher in CD44-positive cell lines, SKOV-3 and OVCAR-8, as compared to CD44-negative cells (CHO). Cytotoxicity of the targeted NPs was significantly higher as compared to non-targeted NPs for the above cell lines. These results suggest that PLGA-PEG-HA NPs could be an efficient delivery system for SN-38 for targeted therapy of ovarian cancer.
Keywords: CD44-targeted delivery; CTAB assay; PLGA nanoparticles; SN-38; hyaluronic acid; ovarian cancer; surface decoration.