A novel nanoparticle drug delivery system based on PEGylated hemoglobin for cancer therapy ZhaoYongmei ChenGang MengZhengjie GongGuangming ZhaoWei WangKaikai LiuTianqing 2019 <p>Proteins such as albumin, gelatin, casein, transferrin, and collagen are widely used as drug delivery systems. However, only albumin-based paclitaxel (PTX) formulation Abraxane<sup>®</sup> (PTX-albumin NPs prepared by nab-technology) has been successfully developed for treating metastatic breast cancer clinically due to abundant materials, simple industrial scale-up process, and well tumor-targeting ability. Hemoglobin (Hb) is another protein used for drug delivery with similar advantages. In this study, we successfully synthesized PEG-Hb nanoparticles loading with PTX based on previously well-established acid-denatured method. PEG-Hb-PTX NPs showed enhanced cellular uptake and great cellular inhibition ability <i>in vitro</i>. Moreover, our animal study showed that PEGylated NPs greatly accumulated in tumor tissues and exhibited excellent anticancer activity <i>in vivo.</i> We found that PEG-Hb-PTX NPs possess a better <i>in vivo</i> antitumor effect than the commercially available Taxol<sup>®</sup> formulation. We believe that PEG-Hb has great potential as an efficient drug delivery system for further clinic study.</p>