Plasma Preparation Strategies for Extracellular Vesicle-Based Biomarkers in Metastatic Castration-Resistant Prostate Cancer

Prima Dewi Sinawang ^1,2,3, Priyanka Multani ^2,3, Mehmet O Ozen ^2,3

¹Department of Chemical Engineering Stanford University Stanford California USA.
²Bio-Acoustic MEMS in Medicine (BAMM) Laboratories, Department of Radiology Stanford University Palo Alto California USA.
³Canary Center at Stanford, Department of Radiology Stanford University Palo Alto California USA.
⁴Department of Tumor Microenvironment & Metastasis H. Lee Moffitt Cancer Center Tampa Florida USA.
⁵Division of Oncology, Department of Medicine University of Utah Salt Lake City Utah USA.
⁶George E. Wahlen Anticoagulation and Thrombosis Service, Division of Hematology and Hematologic Malignancies, Department of Internal Medicine Huntsman Cancer Institute & University of Utah Health Salt Lake City Utah USA.
⁷Molecular Medicine Program University of Utah Salt Lake City Utah USA.
⁸Department of Electrical and Computer Engineering University of Illinois at Urbana-Champaign Urbana Illinois USA.
⁹Department of Bioengineering University of Illinois at Urbana-Champaign Urbana Illinois USA.
¹⁰Nick Holonyak Jr. Micro and Nanotechnology Lab University of Illinois at Urbana-Champaign Urbana Illinois USA.
¹¹Center for Genomic Diagnostics Carl R. Woese Institute for Genomic Biology Urbana Illinois USA.

⁰Department of Chemical Engineering Stanford University Stanford California USA.

Journal of Extracellular Biology +

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August 4, 2025

View abstract on PubMed

Summary

Optimizing plasma sample preparation improves extracellular vesicle (EV) analysis for metastatic castration-resistant prostate cancer (mCRPC). Platelet-poor plasma (PPP) enhances detection of EV biomarkers like miR-375, aiding patient management.

Area Of Science

Biochemistry
Oncology
Nanotechnology

Background

Extracellular vesicles (EVs) are promising for cancer detection, but standardization is lacking.
Clinical utility of EV biomarkers is limited by inconsistent sample preparation and isolation methods.
Accurate analysis of plasma EV content is crucial for metastatic castration-resistant prostate cancer (mCRPC) patient management.

Purpose Of The Study

To investigate the impact of clinical sample preparation variables on plasma-derived EV quality and content in mCRPC patients.
To evaluate the efficacy of the ExoTIC device for EV isolation and biomarker analysis.
To identify optimal biospecimen preparation for enhanced detection accuracy of EV-associated biomarkers.

Main Methods

Assessed effects of anticoagulant choice (EDTA vs. sodium citrate), plasma platelet fraction (platelet-rich vs. platelet-poor), and protease inhibitors.
Isolated EVs using the ExoTIC device.
Characterized EVs and analyzed RNA/protein cargo via nanoparticle tracking analysis, cryogenic electron microscopy, Western blot, and digital PCR.

Main Results

mCRPC-relevant proteins (ARv7, PSMA) were detected in EVs across all tested plasma sample types.
Platelet-poor plasma (PPP) proved optimal for detecting the mCRPC biomarker miR-375.
Elevated EV miR-375 in PPP correlated with poor docetaxel response in progressing mCRPC patients (n=3).

Conclusions

Optimal biospecimen preparation enhances the accuracy of EV biomarker detection for mCRPC.
Standardized EV analysis, particularly using PPP, can improve patient management and therapeutic response prediction.
Detection of plasma EV-associated proteins (ARv7, PSMA) and microRNA (miR-375) holds significant clinical potential.

Keywords:

ARv7 PSMA extracellular vesicles fluidic isolation device metastatic castration‐resistant prostate cancer miR‐375 plasma preparation