In vivo pharmacokinetics, biodistribution and the anti-tumor effect of cyclic RGD-modified doxorubicin-loaded polymers in tumor-bearing mice

Abstract

In our previous study, we successfully produced and characterized a multifunctional drug delivery system with doxorubicin (RC/GO/DOX), which was based on graphene oxide (GO) and cyclic RGD-modified chitosan (RC). Its characteristics include: pH-responsiveness, active targeting of hepatocarcinoma cells, and efficient loading with controlled drug release. Here, we report the pharmacokinetics, biodistribution, and anti-tumor efficacy of RC/GO/DOX polymers in tumor-bearing nude mice. The objective of this study is to assess its targeting potential for tumors. Pharmacokinetic and biodistribution profiles demonstrated that tumor accumulation of RC/GO/DOX polymers was almost three times higher than the others, highlighting the efficacy of the active targeting strategy. Furthermore, the tumor inhibition rate of RC/GO/DOX polymers was 56.64%, 2.09 and 2.93 times higher than that of CS/GO/DOX polymers (without modification) and the DOX solution, respectively. Anti-tumor efficacy results indicated that the tumor growth was better controlled by RC/GO/DOX polymers than the others. Hematoxylin and eosin (H&E) staining showed remarkable changes in tumor histology. Compared with the saline group, the tumor section from the RC/GO/DOX group revealed a marked increase in the quantity of apoptotic and necrotic cells, and a reduction in the quantity of the blood vessels. Together, these studies show that this new system could be regarded as a suitable form of DOX-based treatment of the hepatocellular carcinoma.