This study aims to assess the targeted effect and antitumor efficacy of Gambogic-acid-loaded particles (GA-Ps). GA-Ps with uniform particle sizes of 69.8 ± 17.8 nm (GA-P1), 185.6 ± 33.8 nm (GA-P2), 357.8 ± 81.5 nm (GA-P3), and 7.56 ± 0.95 μm (GA-P4) were prepared using an electrospray technique and exhibited extremely high entrapment efficiency. As the particle size increased from the nano- to microscale, the in vitro GA release rate sharply decreased. After tail-vein injection in mice, GA-P samples GA-P1, GA-P2, GA-P3, and GA-P4 improved the uptake of GA 1.67-times in the liver, 1.78-times in the liver, 2.18-times in the spleen, and 2.35-times in the lung, respectively, compared with GA solution (GA-S). The antitumor efficacy of GA-P2, with an 82.51% targeting efficiency (Te) for the liver, was examined in hepatocellular carcinoma (HCC) model mice. After 2 weeks of administration, HCC mice in the GA-P2 group exhibited a lower degree of tumor invasion and cell lesions in hepatic tissue, recovered liver function, and significantly prolonged survival time, compared with mice in the model, GA-S, and normal saline (NS) groups. Pharmacokinetic studies indicated that the superior antitumor efficacy of GA-P2 was attributed not only to tissue targeting but also to low clearance, extended retention, high bioavailability in plasma, and increased GA stability.
Keywords: antitumor efficacy; electrospray; gambogic acid (GA); gambogic acid-loaded particle (GA-P); tissue targeting.