Abstract 245: Interleukin-4 receptor-targeted Abraxane inhibits tumor growth by enhancing drug delivery and reprogramming of M2-type macrophages into M1 phenotype

Abstract Abraxane, an albumin-bound paclitaxel nanoparticle, is widely used in treating patients with cancer such as breast cancer. The present study aims at a targeted delivery of Abraxane to tumors by conjugating it with IL4RPep-1, an interleukin-4 receptor (IL4R)-binding peptide. IL4R is up-regulated in many tumor cells and M2-polarized macrophages. IL4R-targeted Abraxane (IL4RPep-1-Abx) showed more efficient binding and internalization into IL4R-high tumor cells and M2-type macrophages than untargeted Abraxane, which was inhibited in part by an inhibitor of macropinocytotsis and receptor-mediated endocytosis, respectively, while being completely inhibited by an IL4R-blocking antibody. In the same context, IL4RPep-1-Abx induced higher levels of cytotoxicity to IL4R-high tumor cells and reprogramming of M2-type macrophages into M1-like phenotype than untargeted Abraxane. In vivo fluorescence imaging showed that IL4RPep-1-Abx homed to tumor, with little accumulation in the liver and lung, more efficiently than untargeted Abraxane. In addition, IL4RPep-1-Abx inhibited tumor growth and metastasis to the lung in 4T1 or LLC tumor-bearing mice and reduced the number of tumor nodules in the lung of K-ras transgenic mice more efficiently than untargeted Abraxane. Liver function was maintained within the normal ranges after treatment with IL4RPep-1-Abx. In 4T1 and LLC tumor tissues, IL4RPep-1-Abx reduced the population of immune-suppressive cells such as M2-type macrophages and increased that of immune-stimulatory cells such as CD8+ T cells compared with untargeted Abraxane. These results suggest that IL4R-targeted Abraxane can enhance the therapeutic efficacy and anti-tumor immunity of Abraxane and is a promising strategy for targeted cancer therapy. Citation Format: Poongkavithai Vadevoo Sri Murugan, Gunassekaran Gowri Rangaswamy, Byungheon Lee. Interleukin-4 receptor-targeted Abraxane inhibits tumor growth by enhancing drug delivery and reprogramming of M2-type macrophages into M1 phenotype [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 245.