Biomechanical and biomolecular characterization of large extracellular vesicles

The National Cancer Institute awarded $1.22M to the University of Massachusetts Boston under its Cancer Biology Research program (CFDA 93.396) effective August 1, 2025, through July 31, 2028. This project grant supports fundamental research to advance understanding of extracellular vesicles (EVs)—cell-derived, membrane-bound structures that carry biomolecules and serve as circulating biomarkers for disease diagnosis and therapeutic delivery. The research addresses a critical knowledge gap regarding the biomechanical and biomolecular properties of large microscale EVs (L-EVs), which remain poorly characterized compared to smaller nanoscale exosomes. The project will deliver advanced microfluidic technology capable of measuring single L-EV properties and investigating EV heterogeneity and subtypes associated with glioblastoma-related genetic mutations (EGFR, EGFRvIII, and IDH1), with clinical validation through plasma sample analysis.

The collaborative research team, led by Dr. Dahl at UMass Boston (microfluidics and biomechanics expertise) in partnership with Massachusetts General Hospital sub-awardee Dr. Im (imaging and molecular characterization), will generate comprehensive characterization data on L-EV subpopulations to support downstream clinical applications in cancer diagnosis and treatment monitoring. The project includes a workforce development component, providing undergraduate researchers from UMass Boston with training in biotechnology laboratory techniques, hands-on data acquisition and analysis experience, and integration into the collaborative research team through biweekly presentations and publications, thereby advancing both cancer research capabilities and STEM education outcomes.

Abstract

Extracellular vesicles (EVS) are cell-derived, membrane-bound vesicles that carry various biomolecules (proteins, nucleic acids, lipids) and are found in noninvasive liquid biopsies. They play important roles in cell-to- cell communications as molecular messengers, meaning EVS are also attractive circulating biomarkers for molecular diagnosis of various diseases and carriers for therapeutics. Most previous studies have focused on the biomolecular contents of small nanoscale EVS (also called exosomes). There is less understanding of EVS' mechanical properties and the molecular characteristics of microscale large EVS (L-EVS). EV origins vary widely, and their functions are harder to determine. Investigating EV functions and downstream clinical applications requires rigorous approaches of separating and classifying EVS. The EV field is still determining the characteristics of EV subpopulations and how to best separate them into groups. The overall goal of this project is to investigate L-EV subtypes using our microfluidic technology that will be advanced to measure the biomechanical and biomolecular properties of single L-EVS. The two specific aims propose to investigate L-EV heterogeneity and subtypes from different GBM-associated mutations (e.g., egfr, egfrviii, and IDH1 mutations) and explore the clinical value of multiplex L-EV characterization from plasma samples. The collaborative team has complementary expertise (DR. Dahl at umass boston for microfluidics and biomechanics and DR. IM at massachusetts general hospital for imaging and molecular characterization of EVS). Undergraduate researchers from umass boston will be trained in biotechnology lab techniques at both umass boston and MGH, acquire and analyze data for this project, and be fully integrated into the collaborative research team through their participation and presentation of their work at biweekly project meetings and twice-a-year in-person project symposiums. This proposed work will deepen our understanding of EV biology, especially with the biomechanical properties of EVS, along with their roles as biomarkers. By correlating L-EV stiffness to its biomolecular content, we seek to explain the biomolecular origins of EV stiffness and assess the feasibility of using both physical and chemical properties as biomarkers to classify cancer subtypes more accurately.