Chimeric nanocomposites for the rapid and simple isolation of urinary extracellular vesicles

Cancer cell-derived extracellular vesicles (EVs) are promising biomarkers for cancer diagnosis and prognosis. However, the lack of rapid and sensitive isolation techniques to obtain EVs from clinical samples at a sufficiently high yield limits their practicability. Chimeric nanocomposites of lactoferrin conjugated 2,2-bis(methylol)propionic acid dendrimer-modified magnetic nanoparticles (LF-bis-MPA-MNPs) are fabricated and used for simple and sensitive EV isolation from various biological samples via a combination of electrostatic interaction, physically absorption, and biorecognition between the surfaces of the EVs and the LF-bis-MPA-MNPs. The speed, efficiency, recovery rate, and purity of EV isolation by the LF-bis-MPA-MNPs are superior to those obtained by using established methods. The relative expressions of exosomal microRNAs (miRNAs) from isolated EVs in cancerous cell-derived exosomes are verified as significantly higher than those from noncancerous ones. Finally, the chimeric nanocomposites are used to assess urinary exosomal miRNAs from urine specimens from 20 prostate cancer (PCa), 10 benign prostatic hyperplasia (BPH), patients and 10 healthy controls. Significant up-regulation of miR-21 and miR-346 and down-regulation of miR-23a and miR-122-5p occurs in both groups compared to healthy controls. LF-bis-MPA-MNPs provide a rapid, simple, and high yield method for human excreta analysis in clinical applications.

Automated summary

This study developed lactoferrin-conjugated nanoparticles to achieve simple and sensitive isolation of extracellular vesicles (EVs) through electrostatic interaction, physical absorption, and biorecognition. The method showed faster speed, higher efficiency, recovery rate, and purity compared to established methods. The study also confirmed the significantly higher expression of exosomal microRNAs (miRNAs) from cancer cell-derived exosomes. Finally, the method was applied to analyze urinary exosomal miRNAs from prostate cancer patients and healthy controls, revealing significant up-regulation of miR-21 and miR-346 and down-regulation of miR-23a and miR-122-5p in both groups compared to controls. The method provides a rapid, simple, and high-yield approach for human excreta analysis in clinical applications.