Differential Effects of Extracellular Vesicles from Two Different Glioblastomas on Normal Human Brain Cells

Area of Science:

• Neuro-oncology
• Cell Biology
• Extracellular Vesicles

Background:

• Glioblastomas (GBMs) are aggressive brain tumors with poor prognoses.
• GBM extracellular vesicles (EVs) significantly influence the tumor microenvironment (TME), particularly astrocytes.
• Understanding differential GBM EV effects is crucial for therapeutic development.

Purpose of the Study:

• To investigate if EVs from distinct GBM patient-derived spheroid lines differentially affect recipient brain cell phenotypes.
• To determine the net impact of these altered phenotypes on tumor-related processes.

Main Methods:

• Isolation and characterization of EVs from patient-derived GBM spheroids.
• Treatment of astrocytes and brain slices with GBM EVs.
• Analysis of cellular responses including secretome alterations, signaling pathway modulation (ERK1/2), and gene/protein expression.
• Assessment of conditioned media from treated cells on GBM proliferation.

Main Results:

• GBM EVs induced differential changes in astrocyte secretomes, including pro-inflammatory and proteolytic effects.
• Astrocyte responses involved altered gene/protein expression (e.g., anti-viral) and cytokine release.
• Conditioned media from EV-treated astrocytes enhanced GBM cell proliferation.
• EVs from different GBMs elicited unique cellular and molecular responses.

Conclusions:

• GBM EVs exert 'personalized', tumor-specific effects on the brain tumor microenvironment (TME).
• Observed differential effects challenge the sole reliance on generalized model systems for translational research.
• Despite differential cellular impacts, the net outcome of GBM EV treatment consistently increased GBM tumorigenicity.