Engineered Exosomes Carrying miR-588 for Treatment of Triple Negative Breast Cancer Through Remodeling the Immunosuppressive Microenvironment

Abstract

Zhengjia Zhang,1,* Xinyi Luo,1,* Xiaoxia Xue,1 Mingshi Pang,1 Xiangpeng Wang,1 Liuchunyang Yu,1 Jinxiu Qian,1 Xiaoyu Li,1 Meng Tian,1 Aiping Lu,2 Cheng Lu,3 Yuanyan Liu1 1School of Materia Medica, Beijing University of Chinese Medicine, Beijing, People’s Republic of China; 2School of Chinese Medicine, Hong Kong Baptist University, Kowloon, Hongkong, People’s Republic of China; 3Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Beijing, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yuanyan Liu; Cheng Lu, Email [email protected]; [email protected]: The morbidity and mortality of triple-negative breast cancer (TNBC) are still high, causing a heavy medical burden. CCL5, as a chemokine, can be involved in altering the composition of the tumor microenvironment (TME) as well as the immunosuppressive degree, and has become a very promising target for the treatment of TNBC. Dysregulation of microRNAs (miRNAs) in tumor tissues is closely related to tumor progression, and its utilization can be used to achieve therapeutic purposes. Engineered exosomes can avoid the shortcomings of miRNAs and also enhance their targeting and anti-tumor effects through engineering. Therefore, we aimed to create a cRGD-modified exosome for targeted delivery of miR-588 and to investigate its effect in remodeling immunosuppressive TME by anchoring CCL5 in TNBC.Methods: In this study, we loaded miR-588 into exosomes using electroporation and modified it with cRGD using post insertion to obtain cRGD-Exos/miR-588. Transmission electron microscopy (TEM), nanoparticle tracking assay technique (NTA), Western Blots, qPCR, and flow cytometry were applied for its characterization. CCK-8, qPCR and enzyme-linked immunosorbent assay (ELISA), in vivo fluorescence imaging system, immunohistochemistry and H&E staining were used to explore the efficacy as well as the mechanism at the cellular level as well as in subcutaneous graft-tumor nude mouse model.Results: The cRGD-Exos/miR-588 was successfully constructed and had strong TNBC tumor targeting in vitro and in vivo. Meanwhile, it has significant efficacy on TME components affected by CCL5 and the degree of immunosuppression, which can effectively control TNBC with good safety.Conclusion: In this experiment, cRGD-Exos/miR-588 was prepared to remodel immunosuppressive TME by anchoring CCL5, which is affected by the vicious cycle of immune escape. Overall, cRGD-Exos/miR-588 explored the feasibility of targeting TME for the TNBC treatment, and provided a competitive delivery system for the engineered exosomes to deliver miRNAs for antitumor therapy drug.Keywords: engineered exosome, triple negative breast cancer, miR-588, CCL5, tumor environment

Keywords

• engineered exosome
• triple negative breast cancer
• mir-588
• ccl5
• tumor environment