Wireless Implantable LED Device Treats Deep-Seated Cancers Using Light

Image: The wireless implantable LED-device when combined with a light-sensitive dye destroys cancer cells (Photo courtesy of University of Notre Dame)

Certain types of light, when used in conjunction with a light-activated drug, have been shown to be an effective, minimally invasive treatment for cancers situated on or just beneath the skin. However, cancers that are deep-seated and shielded by layers of tissue, blood, and bone have historically been unreachable by light-based treatments. To extend the therapeutic benefits of light to these more inaccessible cancers, a team of engineers and scientists has developed a wireless, implantable LED device. This innovative device, when used alongside a light-sensitive dye, not only kills cancer cells but also stimulates the immune system’s cancer-targeting response.

Some colors of light have been found to penetrate tissue deeper than others. Green light, which does not penetrate very deeply, is particularly effective at eliciting a strong anti-cancer response. However, before the light can effectively destroy cancer cells, the cells must be treated with a dye that contains light-absorbing molecules. Engineers and scientists at the University of Notre Dame (Notre Dame, IN, USA) have created a device that activates this dye, converting the light into energy that converts the cells’ own oxygen into a toxic agent, thereby turning the cancer cells against themselves. While other treatments also use the cells' oxygen in a similar manner, this device uniquely induces a type of cell death that is especially beneficial.

In their research published in Photodiagnosis and Photodynamic Therapy, the team observed that the treated cells exhibited swelling, indicative of a type of cell death known as pyroptosis. This form of cell death is particularly effective at activating the immune response. The device, small enough to be the size of a grain of rice, can be injected directly into a tumor and activated remotely via an external antenna. The aim is to induce a small amount of pyroptotic cell death, which in turn triggers the immune system to begin attacking the cancer. The device is designed not just to administer treatment but also to monitor the tumor’s response, allowing for adjustments in signal strength and timing as necessary. Future experiments will involve using the device in mice to determine if the immune response triggered in one tumor can encourage the immune system to recognize and attack another cancerous tumor independently.