Silk fibroin nanoparticles and cancer therapy

Curcumin is a potent anticancer molecule naturally derived from the spice turmeric and was combined with silk fibroin (SF) to improve its intracellular bioavailability. This study focused on the fabrication and characterization of SF nanoparticles loaded with curcumin (SF-curcumin) and evaluated their efficacy in vitro using a metastatic breast cancer cell line (GILM2). SF-curcumin nanoparticles were characterized for particle size, morphology, curcumin loading efficiency and release kinetics, efficacy against GILM2 cells, and protein expression profiles using protein microarray. Nanoparticles had an average diameter of 127.7±6.8. nm and a bimodal distribution with most particles falling within the 70- to 110-nm range. SEM showed the nanoparticles had a spherical morphology and aggregated into grape-like structures, which was confirmed using dynamic light scattering. Curcumin release from the nanoparticles showed a typical profile with an initial burst release within the first 24 hours and continued release up to 7 days. The efficacy of SF-curcumin nanoparticles in vitro improved with increased concentration of curcumin and with time. Molecular effects of nanocurcumin on GILM2 cells targeted the high expression of AKT1. Our results indicate that SF nanoparticles may be an attractive nontoxic alternative for the systemic delivery of curcumin.