Researchers have created a nanomedicine-based nasal spray that, in mouse studies, travels straight to the brain and stimulates the immune system to attack aggressive brain tumours. The findings open the door to a non-invasive and potentially game-changing approach for treating conditions such as glioblastoma.
A New Route to the Brain
The innovative therapy uses tiny engineered particles known as spherical nucleic acids (SNAs). Instead of being injected or taken orally, the SNAs are administered through simple nasal drops. From there, they move along the olfactory and trigeminal nerves—pathways that directly link the nasal cavity to the brain. This allows the therapy to bypass the blood–brain barrier, a major obstacle for most brain cancer drugs.
Once inside the brain, the SNAs activate a defence mechanism called the STING pathway. By switching on this pathway, immune cells are alerted to the presence of tumour tissue, prompting them to recognise and attack cancer cells. In experiments involving mice with aggressive glioblastoma—typically considered a “cold” tumour that avoids immune detection—the nasal treatment successfully triggered an immune response that targeted the tumour.
Why the Findings Matter
Glioblastoma remains one of the most difficult cancers to treat. It spreads rapidly, responds poorly to conventional therapies, and survival rates have barely improved over decades. Current treatments often involve complex surgery, radiation, and chemotherapy, all of which carry significant risks and side-effects.
The nasal delivery strategy stands out because:
- It is non-invasive, eliminating the need for brain surgery or direct injections into tumour tissue.
- It offers efficient drug delivery, using nerve pathways instead of the bloodstream to reach the tumour site.
- It boosts the immune system rather than relying solely on tumour-killing drugs.
- In mice, one or two nasal doses combined with T-cell–activating immunotherapies not only cleared tumours but also produced long-lasting immunity against recurrence.
Important Limitations
Although the early results are striking, the research is still in its preclinical stage. Human trials have not yet begun, and scientists caution that several questions remain—such as long-term safety, effectiveness in human patients, and applicability across different glioblastoma subtypes.
Researchers also note that activating the STING pathway alone may not be sufficient. A combination of immune-based strategies will likely be needed to maximise the therapeutic effect.
What Lies Ahead
If future clinical trials show similar outcomes in humans, this nasal nanomedicine could represent a major shift in the treatment of brain cancer—moving from invasive, high-risk procedures to simpler, immune-driven therapies. For patients, this could eventually translate into fewer complications, easier administration, and more durable treatment responses.
(Image credit: kjpargeter/freepik)