Duke University researchers reported in Scientific Reports earlier this week that they have combined an FDA-approved cancer immunotherapy with an emerging tumor-roasting nanotechnology and improved the efficacy of both therapies in a proof-of-concept study using mice. The combination attacks satellite tumors and distant cancerous cells, completely curing two mice and effectively vaccinating one against the disease.
This approach from Duke researchers, Tuan Vo-Dinh, Brant Inman, Greg Palmer, and Paolo Maccarini, relies on a "photothermal immunotherapy" technology in which the researchers use lasers and gold nanostars to heat up and destroy tumors in combination with an immunotherapeutic drug. The photothermal therapy takes advantage of the fact that nanoparticles accumulate preferentially within a tumor due to its leaky vasculature. In addition, the gold nanostars have multiple sharp spikes so that they are able to capture the laser's energy more efficiently. This allows them to work with less exposure, making them more effective deeper within a tissue.
The combined treatment worked so well that one mouse is still alive nearly a year out with zero recurrences of cancer. Even a month later, when the researchers injected more cancerous cells, the mouse's immune system attacked and destroyed them without a problem indicating a vaccine effect in the cured mouse.
The team now plans to follow up with larger cohorts and to work with other clinical researchers to test the treatment in mouse models of brain, breast and lung cancer.
Image: A gold nanostar under an electron microscope. The nanostar's size causes it to accumulate within tumors, where researchers use infrared light to heat it and destroy cancerous growths. Image courtesy of Tuan Vo-Dinh at Duke University.