A novel generic treatment for various forms of cancer

Researchers led by Katsunori Tanaka at the RIKEN Cluster for Pioneering Research (CPR) in Japan and Hiromitsu Haba at the RIKEN Nishina Center for Accelerator-Based Science (RNC) have developed a new technique that has the potential to generically treat several kinds of cancer, with fewer negative side effects than currently available methods.

The new technique relies on basic chemistry and the fact that a compound called acrolein accumulates in cancer cells. In the new study, rather than simply detecting cancer cells, the team targeted those cells for destruction. The logic was fairly simple. Instead of attaching the azide to a fluorescent compound, they attached it to something that can kill a cell without harming surrounding cells. They chose to work with astatine-211, a radionuclide that emits a small amount of radiation in the form of an alpha particle as it decays. Compared to other forms of radiation therapy, alpha particles are a little more deadly, but they can only travel about one-twentieth of a millimeter and can be stopped by a piece of paper. In theory, when astatine-211 is anchored to the inside of a cancer cell, the emitted alpha particles should damage the cancer cell, but not much beyond.

Once the team figured out the best way to attach astatine-211 to the azide probe, they were able to perform a proof-of-concept experiment to test their theory. They implanted human lung-tumor cells into mice and tested the treatment under three conditions: simply injecting astatine-211 into the tumor, injecting the astatine-211-azide probe into the tumor, and injecting the astatine-211-azide probe into the bloodstream. They found that without targeting, tumors continued to grow, and mice did not survive. As expected, when the azide probe was used, tumors grew almost three times less and many more mice survived — 100% when it was injected into the tumor and 80% when injected into the blood.

Reference: Ode et al. (2023) Therapeutic efficacy of 211At-radiolabeled 2,6-diisopropyl phenyl azide in mouse models of human lung cancer. Chem Sci. doi: 10.1039/d3sc02513f