Pterostilbene nanoparticles with small particle size show excellent anti-breast cancer activity in vitro and in vivo

Abstract

Pterostilbene (PTE) is known as resveratrol of the next generation and it has attracted extensive attention in recent years. PTE can inhibit the growth of a variety of tumor cells. To overcome the problem of insolubility, PTE was loaded into nanoparticles (NPs) by anti-solvent precipitation technique using soybean lecithin (SPC) and D-α-tocopheryl polyethylene glycol succinate (TPGS) as stabilizers. The obtained PTE-NPs had an average particle size of 71.0 nm, a polydispersity index （PDI） value of 0.258, and a high zeta potential of −40.8 mV. PTE-NPs can maintain particle size stability in various physiological media. The entrapment efficiency of PTE-NPs was 98.24%. And the apparently water solubility of PTE-NPs was about 53 times higher than the solubility of PTE (54.41 μg ml−1 v−1 s−1. 2.89 mg ml−1). M−1T−1T−1 assay showed that the antitumor activity of PTE-NPs on 4T1 breast cancer cells, MCF-7 breast cancer cells and Hela cervical cancer cells was significantly increased by 4, 6 and 8 times than that of free PTE, respectively. In vivo studies have shown that PTE-NPs has a certain dose dependence. When injected intraperitoneally, PTE-NPs showed a similar therapeutic effect as paclitaxel injection (TIR was 57.53% versus 57.23%) against 4T1 tumor-bearing mice. This should be due to the improved bioavailability of the drug caused by nano-drug delivery system (nano-DDS). These results indicate that PTE-NPs may be a clinically promising anti-tumor drug for breast cancer treatment.