Exosomes in cancer immunoediting and immunotherapy

Abstract

As an important means of communication among cells, exosomes are being studied more and more widely, especially in the context of cancer immunotherapy. In the phase of tumor immunoediting, exosomes derived from tumor cells and different immune cells have complex and changeable physiological functions, because they carry different proteins and nucleic acid from the source cells. Based on the role of exosomes in the communication between different cells, cancer treatment methods are also under continuous research. This review briefly introduces the molecular composition of exosomes, which is closely related to their secretion mechanism. Subsequently, the role of exosomes encapsulating different information molecules is summarized. The role of exosomes in the three phases of tumor immunoediting is introduced in detail, and the relevant literature of exosomes in the tumor immune microenvironment is summarized by using a novel framework for extracting relevant documents. Finally, it summarizes the various exosome-based immunotherapies currently proposed, as well as the challenges and future prospects of exosomes in tumor immunotherapy.

Keywords: Exosomes; Immune escape; Immunotherapy; Tumor immunoediting,.

Graphical abstract

Fig. 1

The secretion mechanism and composition of exosomes. Exosomes originate from endosomes formed by cell membrane invagination. Early endosomes gradually develop into late endosomes containing multiple vesicles after material sorting and transportation. The small vesicles finally released to the outside through membrane fusion are exosomes. Small extracellular vesicles formed by plasma membrane budding may also be considered exosomes. Exosomes have a phospholipid bilayer and rich in tetraspanins, annexins, integrins, chaperones, lipids and nucleic acids.

Fig. 2

The framework is used to explore relevant literature on exosomes and tumor immunity. Step 1: input keywords, search all in PubMed, and count the frequency of keywords. Our keywords are “exosome/small extracellular vesicle”, “tumor/cancer” and “tumor microenvironment”. After screened, 726 articles were obtained. Based on the biomedical network and MORM model to expand and search for related entities, finding relevant entities such as “macrophages”, “dendritic cells”, “mast cells”, “natural killer cells”, “myeloid-derived suppressor cells” and “cytotoxicity T lymphocytes”; Step 2: Fine-tune the named entity recognition model to search for the most relevant documents describing the relationship between keywords and entities. In the end, we obtained 358 target documents.