<p>Multiple myeloma (MM) progression involves extensive immunosuppressive remodeling of the bone marrow microenvironment. In this study, we performed a comprehensive mass spectrometry–based proteomic analysis of exosomes derived from MM cells (MM-Exos), revealing that these exosomal proteins are predominantly enriched in pathways associated with immune regulation. We demonstrated that MM-Exos effectively drive macrophage polarization toward the M2 phenotype, thereby facilitating the establishment and maintenance of an immunosuppressive tumor microenvironment. Mechanistically, we identified the ERK1/2 signaling pathway as a critical mediator of MM-Exo-induced macrophage polarization. Importantly, we found that simvastatin, a widely used inhibitor of cholesterol biosynthesis, effectively impaired exosome secretion from MM cells and subsequently reduced M2 macrophage polarization. Collectively, our study reveals a novel mechanism of immune evasion in MM, in which MM-Exos promote the polarization of macrophages toward the M2 phenotype via ERK1/2 pathway activation. These findings underscore the therapeutic potential of targeting exosome-mediated intercellular communication within the MM bone marrow microenvironment to improve clinical outcomes.</p><p></p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

MM-derived exosomes promote M2 macrophage polarization and immunosuppressive microenvironment: therapeutic opportunities

  • Qi Li,
  • Yilei Shi,
  • Wenzhuo Zhuang,
  • Bingzong Li

摘要

Multiple myeloma (MM) progression involves extensive immunosuppressive remodeling of the bone marrow microenvironment. In this study, we performed a comprehensive mass spectrometry–based proteomic analysis of exosomes derived from MM cells (MM-Exos), revealing that these exosomal proteins are predominantly enriched in pathways associated with immune regulation. We demonstrated that MM-Exos effectively drive macrophage polarization toward the M2 phenotype, thereby facilitating the establishment and maintenance of an immunosuppressive tumor microenvironment. Mechanistically, we identified the ERK1/2 signaling pathway as a critical mediator of MM-Exo-induced macrophage polarization. Importantly, we found that simvastatin, a widely used inhibitor of cholesterol biosynthesis, effectively impaired exosome secretion from MM cells and subsequently reduced M2 macrophage polarization. Collectively, our study reveals a novel mechanism of immune evasion in MM, in which MM-Exos promote the polarization of macrophages toward the M2 phenotype via ERK1/2 pathway activation. These findings underscore the therapeutic potential of targeting exosome-mediated intercellular communication within the MM bone marrow microenvironment to improve clinical outcomes.