Breast cancer treatment strategies often include chemotherapy, which may cause serious side effects because of nonspecific drug action on tumor cells. To solve this problem it is possible to use different nanoparticles for loading of these drugs and provide targeted delivery to the deseased tissues. The goal of this research is to obtain the complex of Doxorubicin (Dox) with iron oxide magnetic nanoparticles (MNP), modified by monoclonal antibody to vascular endothelial growth factor (VEGF), to investigate its biochemical properties and anti-tumor efficiency (therapy and diagnostics) during in vivo experiments.
MNP were synthesized by thermal decomposition of iron acetyl acetonate (III). The coating of these nanoparticles was carried out by bovine serum albumin and polyethylene glycol. The morphology was analyzed by TEM. Dox loading was carried out by adsorption of drug molecules on MNP surface. The sizes of MNP, MNP-Dox and zeta-potential values were analyzed by method of DLS. Cytotoxic activity of samples was determined with MTS-assay (4T1 cell line). Internalization of Dox-loaded nanoparticles in living 4T1 cells was analyzed by confocal microscopy on Nikon A1R MP+. Nanoparticles cellular uptake was measured by flow cytometry (FACS). In vivo experiments were carried out with Balb/c female mice, which have experimental tumor 4T1. Nanoparticles accumulation in tumor in vivo was detected by MRI.
We obtained biocompatible, stable under physiological conditions MNP with core-shell strucrure and Dox-loaded by 8% by weight. MNP-Dox zeta-potential increased with increase of Dox-loading, therefore we proposed electrostatic interactions as driving force of complexation process. Dox-release under acidic condition was more intensive compared to physiological conditions, however Dox-loaded MNP showed quite similar cytotoxicity compared to free Dox. It was shown, that MNP-VEGF-Dox can provide more effective Dox accumulation in 4T1 cells compared with MNP-IgG-Dox due to specific interactions between antibodies and VEGF-receptor. MNP-VEGF-Dox intravenous administration resulted in increased of breast adenocarcinoma mice survivability compared to Dox. In addition MNP-VEGF were able to visualize breast adenocarcinoma during MRI of mice.
Thus, MNP-VEGF seem to be promising tool for tumor MRI-visualization and targeted Dox delivery in breast adenocarcinoma.
Work was supported by by grant of President of Russian Federation МК-6371.2016.7.
Targeted drug delivery and nanocarriers , Nanomedicine for cancer diagnosis & therapy
