Certain types of light have been successful in treating skin cancers when combined with a light-activated drug. However, deep-seated cancers have been challenging to target with light therapy due to their location within tissues and bones.
Researchers at the University of Notre Dame have introduced a wireless LED device that can be implanted to address these hard-to-reach cancers. By utilizing a light-sensitive dye in conjunction with this device, not only are cancer cells eliminated, but the body’s immune response against cancer is also activated. Their findings were recently published in Photodiagnosis and Photodynamic Therapy.
“Certain colors of light can penetrate tissues more effectively than others,” explained Thomas O’Sullivan, an associate professor of electrical engineering and co-author of the study. “We found that green light, which doesn’t penetrate deeply, can trigger a stronger response against cancer cells.”
Prior to light therapy, a dye containing light-absorbing molecules is applied to the cancer cells. The LED device activates the dye, converting light into energy that renders the cells’ oxygen toxic, essentially turning the cancer cells against themselves.
This treatment induces a unique form of cell death that promotes an immune response. Bradley Smith, the Emil T. Hofman Professor of Science and co-author, highlighted the observation of cell swelling, indicating a specific type of cell death called pyroptosis that stimulates the immune system’s response.
The researchers aim to trigger a controlled amount of pyroptotic cell death to prompt the immune system to battle the cancer. Future experiments involving mice will investigate whether this cancer-fighting response can target other tumors independently.
The LED device, comparable in size to a grain of rice, can be directly inserted into a tumor and activated remotely using an external antenna. Besides treatment delivery, it can monitor the tumor’s progress, adjusting signals as necessary.
This study was supported by Seed Transformative Interdisciplinary Research (STIR) grants established in 2023 by Notre Dame’s College of Science and College of Engineering. The grants aim to ignite research initiatives in health, environment, and information technologies.