International Journal of Nanomedicine (Dec 2015)
Biodegradable Eri silk nanoparticles as a delivery vehicle for bovine lactoferrin against MDA-MB-231 and MCF-7 breast cancer cells
Abstract
Kislay Roy,1,* Yogesh S Patel,1,* Rupinder K Kanwar,1 Rangam Rajkhowa,2 Xungai Wang,2 Jagat R Kanwar1 1Nanomedicine-Laboratory of Immunology and Molecular Biomedical Research (NLIMBR), Centre for Molecular and Medical Research (C-MMR), School of Medicine (SoM), Faculty of Health, 2Institute for Frontier Materials (IFM), Deakin University, Waurn Ponds, VIC, Australia *These authors contributed equally to this work Abstract: This study used the Eri silk nanoparticles (NPs) for delivering apo-bovine lactoferrin (Apo-bLf) (~2% iron saturated) and Fe-bLf (100% iron saturated) in MDA-MB-231 and MCF-7 breast cancer cell lines. Apo-bLf and Fe-bLf-loaded Eri silk NPs with sizes between 200 and 300 nm (±10 nm) showed a significant internalization within 4 hours in MDA-MB-231 cells when compared to MCF-7 cells. The ex vivo loop assay with chitosan-coated Fe-bLf-loaded silk NPs was able to substantiate its future use in oral administration and showed the maximum absorption within 24 hours by ileum. Both Apo-bLf and Fe-bLf induced increase in expression of low-density lipoprotein receptor-related protein 1 and lactoferrin receptor in epidermal growth factor (EGFR)-positive MDA-MB-231 cells, while transferrin receptor (TfR) and TfR2 in MCF-7 cells facilitated the receptor-mediated endocytosis of NPs. Controlled and sustained release of both bLf from silk NPs was shown to induce more cancer-specific cytotoxicity in MDA-MB-231 and MCF-7 cells compared to normal MCF-10A cells. Due to higher degree of internalization, the extent of cytotoxicity and apoptosis was significantly higher in MDA-MB-231 (EGFR+) cells when compared to MCF-7 (EGFR-) cells. The expression of a prominent anti-cancer target, survivin, was found to be downregulated at both gene and protein levels. Taken together, all the observations suggest the potential use of Eri silk NPs as a delivery vehicle for an anti-cancer milk protein, and indicate bLf for the treatment of breast cancer. Keywords: breast cancer, silk nanoparticles, bovine lactoferrin, epidermal growth factor receptor, apoptosis