What if one of the deadliest brain cancers could one day be treated through the nose? Scientists in the United States are exploring that possibility in a study that could reshape how doctors approach glioblastoma, an aggressive cancer with few effective treatment options.
Researchers at Washington University School of Medicine, working with Northwestern University, are testing whether nasal drops carrying tiny nanostructures can slip directly into the brain and spark an immune response against tumours. Their findings, published in the journal PNAS, offer an early but striking demonstration that a non-invasive approach might work.
Glioblastoma affects only a few people per hundred thousand, yet it remains one of the most feared cancers because of how fast it spreads and how poorly it responds to treatment. The biggest obstacle has always been the brain’s own defence system. The blood-brain barrier blocks most medicines, making it extremely difficult to deliver drugs where they are needed.
The research team decided to take a different route: bypass the barrier entirely by using the nose. The olfactory nerve provides a direct connection to the brain, and the scientists believe this pathway can be used to carry therapeutic molecules without surgery or other invasive procedures.
At the centre of the experiment are spherical nucleic acids, a form of nanotechnology developed at Northwestern. These tiny structures are engineered to hold strands of genetic material around a nanoparticle core, allowing them to transport drugs more effectively than many traditional delivery systems. In this case, they carry medicines designed to activate a pathway known as STING, which can turn a dormant tumour environment into one that alerts the immune system.
Glioblastoma tumours are often called cold tumours because the immune system barely recognises them. Activating the STING pathway is meant to heat up the response, helping the body identify and attack cancer cells. The challenge is that STING-based drugs usually break down too quickly and often require direct injections into the tumour, a method that is painful and not suitable for repeated use.
A member of the Washington University team, postdoctoral researcher Akanksha Mahajan, proposed using spherical nucleic acids to carry the STING-activating drugs through the nose. In mouse studies, the approach succeeded in reaching the brain and triggering the desired immune activity.
Scientists say the method has the potential to open a new chapter in brain cancer treatment. The hope is to stimulate strong immune pathways within the brain without putting patients through repeated surgical procedures.
The work is still in its early stages, and human trials remain some distance away. However, the findings mark one of the most inventive efforts in years to tackle a cancer that has long resisted conventional therapies. For researchers and patients, this approach represents a rare sense of possibility in a field where progress is often slow and outcomes are grim.
