The theranostic efficiency of tumor-specific, pH-responsive, peptide-modified, liposome-containing paclitaxel and superparamagnetic iron oxide nanoparticles

Xiu-Chai Zheng,1,2,* Wei Ren,1,2,* Shuang Zhang,1,2 Ting Zhong,1,2 Xiao-Chuan Duan,1,2 Yi-Fan Yin,1,2 Mei-Qi Xu,1,2 Yan-Li Hao,1,2 Zhan-Tao Li,1,2 Hui Li,1,2 Man Liu,1,2 Zhuo-Yue Li,1,2 Xuan Zhang1,2 1Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing, People’s Republic of China; 2Department of Pharmaceutics, School of Pharmaceutical Sciences, Peking University, Beijing, People’s Republic of China *These authors contributed equally to this work Background: In the present study, the tumor-specific, pH-responsive peptide H7K(R2)2 -modified, theranostic liposome-containing paclitaxel (PTX) and superparamagnetic iron oxide nanoparticles (SPIO NPs), PTX/SPIO-SSL-H7K(R2)2, was prepared by using H7K(R2)2 as the targeting ligand, SPIO NPs as the magnetic resonance imaging (MRI) agent, PTX as antitumor drug. Methods: The PTX/SPIO-SSL-H7K(R2)2 was prepared by a thin film hydration method. The characteristics of PTX/SPIO-SSL-H7K(R2)2 were evaluated. The targeting effect, MRI, and antitumor activity of PTX/SPIO-SSL-H7K(R2)2 were investigated detail in vitro and in vivo in human breast carcinoma MDA-MB-231 cell models. Results: Our results of in vitro flow cytometry, in vivo imaging, and in vivo MR imaging confirmed the pH-responsive characteristic of H7K(R2)2 in MDA-MB-231 cell line in vitro and in vivo. The results of in vivo MRI and in vivo antitumor activity confirmed the theranostic effect of PTX/SPIO-SSL-H7K(R2)2 in MDA-MB-231 tumor-bearing model. Conclusion: Considering all our in vitro and in vivo results, we conclude that we developed targeting modified theranostic liposome which could achieve both role of antitumor and MRI. Keywords: tumor-specific pH-responsive peptide, paclitaxel, superparamagnetic iron oxide nanoparticles, liposome, theranostic efficiency