In vitro evaluation of antitumor activity of doxorubicin-loaded nanoemulsion in MCF-7 human breast cancer cells

Doxorubicin (DOX) is an anticancer drug used to treat several cancer diseases. However, it has several dose limitation aspects because of its poor bioavailability, hydrophobicity, and cytotoxicity. In this study, five nanoemulsion (NE) formulations, containing soya phosphatidylcholine/polyoxyethylenglycerol trihydroxy-stearate 40 (EU)/sodium oleate as surfactant, cholesterol (CHO) as oil phase, and Tris–HCl buffer (pH 7.22), were produced. The NE droplets morphologies of the entire blank and DOX-loaded formulations, revealed by the transmission electron microscope, were spherical. The droplet sizes of blank NEs, obtained between 2.9 and 6.4 nm, decreased significantly with the increase in the ratio of surfactant-to-oil, whereas the droplets sizes of DOX-loaded NE formulations were significantly higher and found in the range of 7.7–15.9 nm. The evaluation for both blank and DOX-loaded NE formulations proved that the NE carrier had improved the DOX efficacy and reduced its cytotoxicity. It showed that the cell growth inhibition of the breast cancer cells (MCF-7) have exceeded the commercial DOX by a factor of 1.7 with increased apoptosis activity and minimal cytotoxicity against the normal human foreskin cells (HFS). In contrast, commercial DOX was found to exhibit a significant non-selective toxicity against both MCF-7 and HFS cells. In conclusion, we have developed DOX-loaded NE formulations which selectively and significantly inhibited cell proliferation of MCF-7 cells and increased apoptosis.