Exosomal PD-L1 harbors active defense function to suppress T cell killing of breast cancer cells and promote tumor growth

• 来源期刊: 细胞研究（英文版）
• 年，卷（期）: 2018,（8）
• 页码范围: 862-864
• 页数: 3页
• 语种: 英文

摘要

Dear Editor, The tumor-microenvironment interactions play important roles in tumor progression, metastasis, and therapeutic resistance,1 and increasing evidence indicates that tumor cell-derived exosomes can systematically modulate or reprogram the tumor microenvironment by transferring molecules, such as microRNAs, mRNAs, and proteins from donor cells to recipient cells.2 PD-L1 is a classical immune surface protein, which inhibits anti-tumor function of T cells by binding to its receptor programmed cell death-1 (PD-1) and effectively protects tumor from immune surveillance.3 Exosomes have been reported to contain certain types of proteins, including membrane proteins, e.g., EGFR and MET, that promote cancer metastasis.4,5 As a membrane-bound protein, whether PD-L1 exists in cancer cell-derived exosomes and whether it plays a role in tumor progress are largely unknown.