A new generic treatment for multiple types of cancerDate: June 27, 2023
Source: RIKEN
Summary: Researchers have developed a new type of tumor-targeted alpha-particle therapy that has the potential to generically treat several kinds of cancer, with fewer negative side effects than currently available methods. The proof-of-concept study showed that tumors in mice grew almost three times less and survival was 100% after just one injection of a compound that is designed to emit small amounts of alpha radiation from the inside of cancer cells, thus killing them but sparing healthy tissue.
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. Published on June 27 in Chemical Science, the proof-of-concept study showed that tumors in mice grew almost three times less and survival was 100% after just one injection of a compound that is designed to emit small amounts of alpha radiation from the inside of cancer cells, thus killing them but sparing healthy tissue.
The side effects of standard chemotherapy and radiation treatment can be devastating, and the eradication of all cancer cells is not guaranteed, especially when the cancer has already metastasized and spread throughout the body. Therefore, the goal of most research these days is to find a way to specifically target cancer cells so that treatments only affect tumors. Some targeted treatments do exist, but they cannot be applied to all cancers. “One of the greatest advantages of our new method,” says Tanaka, “is that is can be used to treat many kinds of cancer without any targeting vectors, such as antibodies or peptides.”
The new technique relies on basic chemistry and the fact that a compound called acrolein accumulates in cancer cells. A few years ago, Tanaka’s team used a similar technique to detect individual breast cancer cells. They attached a fluorescent compound to a specific type of azide—an organic molecule with a group of three nitrogen atoms (N3) at the end. When the azide and acrolein meet inside a cancer cell, they react, and the fluorescent compound becomes anchored to structures inside the cancer cell. Because acrolein is almost absent from healthy cells, this technique acted like a probe to light up cancer cells in the body.
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. The 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 a cancer cell, the emitted alpha particles should damage the cancer cell, but not much beyond.
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Source:
https://www.sciencedaily.com/releases/2023/06/230627225205.htm
