90 K increased delivery efficiency of extracellular vesicles through mediating internalization

Area of Science:

• Oncology
• Immunology
• Biochemistry

Background:

• Extracellular vesicles (EVs) play roles in cancer progression and immune modulation.
• Identifying specific EV components can reveal prognostic markers and therapeutic targets.

Purpose of the Study:

• To identify novel prognostic biomarkers for head and neck cancer (HNC) on EVs.
• To investigate the role of identified EV proteins in regulating the tumor microenvironment and immune responses.
• To explore the potential of EV modification for therapeutic applications.

Main Methods:

• Mass spectrometry-based high-throughput proteomics to identify EV proteins.
• Analysis of serum EV 90 K levels in HNC patients.
• In vivo studies using immune-competent mice to assess the immune-suppressive effects of tumor-derived EVs (TDEs).
• Investigation of molecular interactions (integrin-β1, anti-siglec-9) and cargo (miR-21) within EVs.

Main Results:

• 90 K was identified as a membrane protein on EVs, and its levels in serum EVs independently predict poor overall survival in HNC patients.
• TDEs containing 90 K induced an immune-suppressive microenvironment in mice, mediated by myeloid-derived suppressor cells (MDSCs) and encapsulated miR-21.
• 90 K facilitates TDE cargo internalization via interactions with integrin-β1 and anti-siglec-9.
• Modifying γδT cell-derived EVs (γδTEVs) with 90 K enhanced the delivery and therapeutic efficacy of PD-L1 siRNA.

Conclusions:

• 90 K is a prognostic biomarker for HNC and a key mediator of TDE-mediated immune suppression.
• 90 K's role in cargo internalization suggests its utility in enhancing EV-based drug delivery systems.
• Targeting 90 K or utilizing its cargo-transporting function holds promise for novel cancer therapies.