Glioblastoma is among the most devastating of cancers: fewer than 30 percent of patients survive two years, and the standard treatment — surgery, radiation, and chemotherapy with temozolomide — has changed little in decades. A major barrier to progress has been physical. The blood-brain barrier, a tightly sealed network of endothelial cells, blocks nearly all therapeutic molecules from reaching the brain, and glioblastoma’s aggressive invasion into surrounding tissue makes complete surgical removal impossible.
A team at Oregon State University’s College of Pharmacy has now demonstrated a novel approach that exploits the body’s own glucose transport system to sneak therapeutic mRNA past this barrier. In a study published in the Journal of Controlled Release, the researchers showed that lipid nanoparticles coated with mannose — a sugar that is chemically similar to glucose — can cross the blood-brain barrier via GLUT1 transporters and deliver messenger RNA that restores the tumor-suppressing protein PTEN directly to glioblastoma cells.
The coating trick
The key innovation is a chemical modification to the lipid nanoparticle itself. Mannose, a glucose epimer that differs from glucose at a single carbon atom, was conjugated directly to cholesterol, a structural lipid that makes up roughly 40 percent of the nanoparticle. This achieved a surface density of approximately 30 percent mannose — a six-fold improvement over conventional PEG-lipid functionalization, which typically tops out at about 5 percent. The high density is essential because blood glucose circulates at millimolar concentrations, meaning the nanoparticles must outcompete glucose for binding to GLUT1.
“This is what makes our platform unique,” said Olena Taratula, co-corresponding author. “The same sugar that allows the nanoparticle to cross the blood-brain barrier also helps it target the tumor, because glioblastoma cells express GLUT1 at roughly three times the level of normal brain tissue.”
Results in mice
In an orthotopic glioblastoma mouse model, the mannose-coated nanoparticles carrying PTEN mRNA achieved a 9.9-fold increase in brain accumulation compared to non-targeted nanoparticles. Tumor burden at day 28 shrank roughly six-fold, and median survival increased from 33 days to 49 days — a 50 percent extension. No measurable organ toxicity was detected across repeated dosing.
The team also validated the platform using Cre mRNA in reporter mice, demonstrating that the delivered mRNA was translated into functional protein in neurons and astrocytes, confirming true brain-parenchymal delivery rather than mere endothelial uptake.
PTEN and glioblastoma
Loss of the PTEN tumor-suppressor gene occurs in roughly 40 percent of glioblastomas, driving uncontrolled growth through hyperactivation of the PI3K/AKT signaling pathway. The mRNA therapy restores PTEN expression, reinstating the cell’s natural growth-control mechanisms. As a transient therapy rather than a permanent genetic modification, mRNA delivery offers a safety advantage: the treatment is reversible and titratable.
Caveats
All results come from a mouse model. Many therapies that show promise in murine glioblastoma fail in human trials, where tumor heterogeneity and the human immune microenvironment introduce complexities that animal models cannot replicate. The therapy depends on GLUT1 overexpression, which may not be uniform across all tumor cells. Clinical trials have not yet been announced, and translation from mouse to human typically takes years.
Sources
- Goo YT, Cataldi VN, Grigoriev V, et al. “Single-ligand dual-targeting lipid nanoparticles for therapeutic mRNA delivery to glioblastoma across the blood-brain barrier.” Journal of Controlled Release 396, 115107, 2026. DOI: 10.1016/j.jconrel.2026.115107
- Oregon State University press release via ScienceDaily