Why it matters. Glioblastoma kills the vast majority of patients within a few years worldwide, and getting drugs past the brain's protective barrier is a problem researchers everywhere are racing to solve — so a less toxic, more targeted delivery route is globally relevant.
Background. The work comes from a collaboration between Seoul St. Mary's Hospital — a major teaching hospital run by the Catholic University of Korea — and POSTECH (Pohang University of Science and Technology), one of South Korea's elite research universities known for science and engineering. South Korea invests heavily in biomedical and nanotechnology research, and such hospital-university partnerships are a common engine for its translational medicine output.
What to watch next. The next hurdle is moving from mouse studies toward larger-animal and eventual human trials to confirm the method is safe and effective in people.
A South Korean research team has developed a new way to treat glioblastoma — one of the deadliest adult brain cancers — by delivering chemotherapy nanoparticles through the nose and steering them to the tumor with an external magnetic field. The teams, led by neurosurgeon Yang Seung-ho of Seoul St. Mary’s Hospital and chemists and engineers at POSTECH, announced the animal-study results on June 11, with the work published in the journal Drug Delivery and Translational Research.
Why glioblastoma is so hard to treat
Glioblastoma is the most common malignant brain tumor in adults and remains notoriously difficult to cure. Even with standard treatment, patients survive about 15 months on average, and the 10-year survival rate is just 5.3%.
Part of the problem is the blood-brain barrier (BBB), a protective layer that keeps most substances out of the brain. The frontline drug temozolomide is taken as a pill, but it struggles to cross the barrier in meaningful amounts. That means low efficiency inside the tumor and unwanted side effects throughout the body.
Two ideas combined: the nose and a magnet
The researchers tackled the barrier from a different angle. First, instead of routing the drug through the bloodstream, they used the olfactory nerve — the smell-sensing nerve that connects directly to the brain — as a delivery channel. Second, they bound the drug to magnetic particles so its movement could be guided from outside the skull.
In practice, temozolomide was attached to 56-nanometer superparamagnetic iron oxide nanoparticles (SPIONs). This complex was administered through the nose, then directed toward the tumor using transcranial magnetic stimulation (TMS), a non-invasive technique that applies magnetic fields to the head.
What the experiments showed
In cell tests, the nanoparticle complex killed tumor cells as effectively as the conventional drug. Electron microscopy confirmed the particles spread evenly, reaching even the nuclei of tumor cells.
The animal study followed mice with induced glioblastoma for 90 days. The results lined up clearly by median survival:
- 72 days — mice given the complex and then TMS guidance
- 51 days — mice given the complex alone
- 27 days — untreated control group
That amounts to up to a 2.7-fold extension in survival compared with no treatment. Strikingly, the effect held even though the dose was cut to just 5.6% of the standard oral amount. Precise tissue analysis using liquid chromatography–tandem mass spectrometry showed that the magnetic field meaningfully raised drug concentrations inside the brain tissue at the tumor site.
What the researchers say
“By combining nasal delivery with transcranial magnetic stimulation, this approach effectively bypasses the blood-brain barrier while sharply reducing the side effects of conventional chemotherapy, such as systemic immune suppression,” said Professor Yang. He added that he hopes the method can help “turn glioblastoma into a condition that can be managed over the long term.”
The findings are early and limited to laboratory and animal models, but they point toward a less toxic, more targeted route for getting cancer drugs into the brain.
