In Situ Simultaneous Detection of Surface Protein and microRNA in Clustered Extracellular Vesicles from Cancer Cell...

Area of Science:

• Biochemistry
• Molecular Biology
• Nanotechnology

Background:

• Extracellular vesicles (EVs) are crucial biomarkers in liquid biopsy for cancer detection due to their circulating nature and diverse molecular cargo.
• Accurate cancer diagnosis necessitates multiplexed biomarker detection from heterogeneous cancer cell-derived EVs.
• In situ EV biomarker detection offers enhanced efficiency, addressing challenges in handling these nanoparticles.

Purpose of the Study:

• To develop an in situ method for simultaneous detection of EV surface protein PD-L1 and internal miR-21 for breast cancer liquid biopsy.
• To overcome the limitation of flow cytometry in detecting small EVs by inducing EV clustering.

Main Methods:

• Developed a flow cytometry-based assay for simultaneous in situ detection of PD-L1 and miR-21 in extracellular vesicles.
• Utilized 1,2-distearoyl-sn-glycero-3-phosphoethanolamine (DSPE)-polyethylene glycol-DSPE to induce extracellular vesicle clustering.
• Analyzed biomarker detection signals from clustered extracellular vesicles.

Main Results:

• Induced extracellular vesicle clustering significantly amplified PD-L1 and miR-21 detection signals.
• Clustering enabled clear differentiation between cancer cell-derived EVs and normal cell-derived EVs.
• The developed method demonstrated a substantial increase in sensitivity and accuracy for EV-based liquid biopsy.

Conclusions:

• In situ simultaneous detection of EV biomarkers, including PD-L1 and miR-21, is feasible using flow cytometry.
• EV clustering is an effective strategy to enhance the detectability of small EVs for improved biomarker analysis.
• This approach significantly advances the sensitivity and accuracy of extracellular vesicle-based liquid biopsy for cancer diagnosis.