Scientists from the University of Cambridge have made a surprising discovery about how aspirin might help stop cancer from spreading.
Their research shows that aspirin can reduce the spread of some cancers by boosting the body’s immune system.
This new finding could help guide future treatments and clinical trials. The study was published in the journal Nature and mainly funded by the Medical Research Council.
Aspirin is a common medicine that people have used for over a century to reduce pain, fever, and inflammation. It’s also often taken in low doses to prevent heart attacks and strokes, because it stops blood from clotting too easily.
But over the years, researchers noticed something interesting—people who regularly took low-dose aspirin seemed to have a lower chance of their cancer spreading, especially for breast, bowel, and prostate cancers. Scientists were unsure why this was happening until now.
In this new study, researchers were originally trying to learn more about metastasis, the process where cancer spreads from one part of the body to another. Even though cancer often starts in one place, about 90% of cancer-related deaths happen when it spreads.
Scientists know that when cancer cells move away from the main tumor and travel alone, they are more exposed and easier for the immune system to attack. In contrast, large tumors can hide from the immune system by creating an environment that weakens it.
The Cambridge researchers studied mice and looked at 810 different genes to find out which ones affect cancer spread. They found 15 genes of interest, and one in particular stood out—a gene that makes a protein called ARHGEF1.
Mice that did not have this gene had fewer cancer metastases in the lungs and liver. It turns out that ARHGEF1 weakens the immune system by stopping T cells from working. T cells are a type of immune cell that can destroy cancer cells, especially when they are alone and trying to spread.
To find a way to target this gene, the team looked deeper into the cell’s signaling system and discovered that a molecule called thromboxane A2 (TXA2) turns on ARHGEF1.
This was a big surprise. TXA2 is made by platelets—cells in the blood that help stop bleeding by forming clots. Too much TXA2 can cause dangerous clots that lead to heart attacks or strokes. Aspirin works by lowering TXA2, which is why it’s used to prevent heart problems.
Now, the scientists realized that aspirin might also help stop cancer from spreading by lowering TXA2 and allowing T cells to attack cancer more freely. In tests with mice that had melanoma, those given aspirin had fewer cancer metastases than those that were not, and the benefit came from allowing the immune system to fight back.
Professor Rahul Roychoudhuri, who led the study, said that even though many patients get surgery or early treatment for cancer, the disease sometimes comes back because tiny cancer cells hide in the body.
He believes there is a short window after cancer starts to spread where the immune system has a good chance to stop it—and aspirin might help during that time.
Dr. Jie Yang, who also worked on the research, said that finding out TXA2 was involved felt like a “Eureka moment.” The discovery completely changed the direction of their research and opened up a new way of thinking about aspirin’s role in fighting cancer.
While this is exciting news, scientists warn that aspirin isn’t safe for everyone. For some people, it can cause stomach bleeding or ulcers. That’s why clinical trials are needed to figure out who would benefit the most.
One such trial is the Add-Aspirin trial, led by Professor Ruth Langley in London. She hopes the new study will help them better understand which patients should take aspirin after a cancer diagnosis.
This research highlights a new path for cancer treatment that could be simpler and more affordable than current methods like antibody therapies. If aspirin or similar drugs can safely help the immune system fight cancer early on, they could offer new hope to people around the world.
If you care about cancer, please read studies about Researchers find a new cause of cancer and findings of Scientists make a big breakthrough in prostate cancer treatment.
For more about cancer, please read studies about Research finds a new cause of cancer growth and findings of Scientists find the missing link between autoimmune diseases and blood cancer.
The study is published in Nature.
Copyright © 2025 Knowridge Science Report. All rights reserved.
