Aspirin May Prevent Metastasis of Cancer

Scientists at the University of Cambridge, who have been investigating how certain common medications might hold back the movement of cancer cells, have found that daily low-dose aspirin use could curb the spread of certain cancers, including breast and prostate tumors.

According to the researchers, when a tumor stays in one spot, doctors often have a chance to remove or treat it. However, when the cancer cells slip into the bloodstream and lodge in other areas, they create metastatic growths that are much harder to manage. Therefore, knowing that small, lone cancer cells traveling through the body might be more open to immune system attacks than large tumors, the researchers tested this idea by looking for the factors that shrink or boost immune defense.

They found that thromboxane A2, often called TXA2, which is produced by platelets, triggers a pathway in T cells involving a protein called ARHGEF1, limiting the ability of these T cells to attack cancer. Aspirin blocks the enzyme that leads to the creation of TXA2. When TXA2 levels drop, T cells have more energy to find and eliminate microscopic cancer threats. “It was a eureka moment when we found TXA2 was the molecular signal that activates this suppressive effect on T cells,” said Jie Yang, PhD, a researcher in the department of pathology.

The experts found that the protein ARHGEF1 makes T cells weaker, so they don’t fight cancer as well. When they stopped ARHGEF1 from doing this, the T cells stayed strong and attacked cancer more effectively. As a result, fewer cancer cells spread in the mice they tested. In simple terms, the aspirin pathway stifles TXA2 production, which then allows T cells to keep doing their job without being put to sleep by that clotting factor.

The researchers suspect that, in many people, this added boost could stand between remission and a devastating cancer comeback.