Image: Sonodynamic therapy may offer a new option for treating glioma (Photo courtesy of Shutterstock)
Combining 5-ALA, a drug that sensitizes cancer to sound waves, and focused ultrasound is far more effective than either alone in killing glioblastoma cells, claims a new study.
Under investigation by researchers at the University of Virginia Health Sciences Center (Charlottesville, USA) and Fondazione IRCCS Istituto Neurologico C. Besta (Milan, Italy), sonodynamic therapy (SDT) is an emerging modality for cancer treatment which combines ultrasound with sonosensitizers to produce a localized cytotoxic effect. The aim of the study was to demonstrate the efficacy of SDT with fluorescein (FL) and low-intensity focused ultrasound in inhibiting the growth of ectopic gliomas implanted in a rat’s subcutaneous tissue.
For the study, in vivo cytotoxicity of FL-SDT was evaluated in C6 rat glioma cells which were inoculated subcutaneously. They then examined the benefits of 5-ALA and focused ultrasound, both individually and in combination, and found that the pairing was far more effective than either alone. While the drug alone reduced the number of viable cancer cells by 5%, focused ultrasound reduced it by 16%. Together, the reduction was 47%. The study was published on June 4, 2020, in the Journal of Neuro-Oncology.
“Sonodynamic therapy with focused ultrasound offers a new therapeutic approach to treating patients with malignant brain tumors,” said study co-author neurosurgeon Jason Sheehan, MD, PhD, of UVA Health. ""Focused ultrasound has the potential to improve outcomes for patients with complex brain tumors and other neurosurgical pathologies. We may be at the tip of the iceberg in terms of intracranial indications for focused ultrasound.”
Focused ultrasound is based on nonlinear acoustic mathematical optimization methods to analyze and simulate the propagation of sound in material. The information is then used to enhance the shape of an acoustic lens in such a way that that ultrasound pressure is focused precisely on the location of the tissue to be treated, while the surrounding tissue retains as little damage as possible.
University of Virginia Health Sciences Center
Fondazione IRCCS Istituto Neurologico C. Besta