Brain tumors are not always successfully treated with conventional treatments. A team from Empa and the hospital network HOCH Health Ostschweiz is therefore developing a nanozyme that can directly attack cancer cells in the brain during tumor surgery. This project was made possible thanks to the generous support of several foundations.
Among malignant brain tumors, astrocytomas are particularly common and equally dangerous. Surgical removal of this actively growing tumor can be difficult because the cells invade surrounding healthy tissue. Furthermore, in 7 out of 10 cases, the cancer recurs after treatment, and the prognosis is correspondingly poor. The five-year survival rate is only about 5%. Now, a team at the hospital network HOCH Health Ostschweiz in Empa and St. Gallen, led by neurosurgeon Isabelle Hostetler, hopes to improve the chances of curing this type of tumor with a new, gentler treatment based on so-called nanozymes. This project is being carried out thanks to the generous support of the Hedy Groh-Meyer Foundation, the Swiss Cancer Foundation and four other foundations.
bypass the blood-brain barrier
Currently, treatment for astrocytomas includes a combination of surgery, radiation, and chemotherapy. However, the location of the tumor, i.e. the brain, poses a problem, especially with drug therapy. This is because the blood-brain barrier, the body’s own protective mechanism that protects organs from harmful effects from the bloodstream, prevents certain therapeutic drugs from reaching the brain.
Empa researcher Giacomo Reina and his team at the Institute for Health Nanomaterials in St. Gallen now hope to circumvent this barrier with a clever approach. They are developing biocompatible nanomaterials that can act as nanomedicines that can be used directly in the field during brain tumor surgery. “Cancer cells are particularly metabolically active, so drugs accumulate specifically in tumor tissue,” says Reyna. Another advantage is that nanozymes can be activated with near-infrared light to obtain particularly precise and controllable effects.
Gentle but powerful
This new treatment combines several mechanisms of action. Nanozymes, nanomaterials with enzyme-like activities, can, for example, activate inactive precursors of drugs or generate reactive oxygen compounds that damage tumor cells. Their small size allows them to penetrate deep into tissues and attack malignant cells several millimeters away. Furthermore, thanks to its ability to be activated by IR light, the dosage and side effects of the treatment can be minimized.
The team is now ready to tackle its ambitious goals. At the end of the four-year project, nanomedicine should be ready for clinical trials as a minimally invasive and low-impact treatment to existing treatments. Researchers have high expectations as follows. ”Nanozymes may even prevent astrocytoma recurrence if the tumor is already resistant to conventional chemotherapy” says Giacomo Reina. Furthermore, this approach has promising potential for the treatment of other brain and spinal cord tumors.
Empa Research Initiative “Oncology”
Cancer remains one of the biggest challenges to public health in Switzerland, with around 45,000 new infections and 17,000 deaths each year. Empa’s Oncology Initiative aims to address this problem with an innovative materials-based approach that takes into account a patient’s genetic and metabolic fingerprint. Empa’s five laboratories bring together expertise in (nano)materials science, sensor technology, imaging, and advanced in vitro and in silico models to develop new strategies for diagnosis, monitoring, and treatment. The aim is to implement these innovative approaches in collaboration with clinic and industry partners. The first phase of this initiative will run from 2025 to 2035. Another example of a project in the oncology effort is investigating thyroid cancer using innovative 3D imaging technology. This technology allows for a more precise and above all non-destructive analysis of biopsy samples.

