HQ Team
March 10, 2025: University of Cambridge scientists have uncovered the mechanism behind how aspirin could reduce the spread of certain cancers by stimulating the immune system. The findings could pave the way for targeted use of aspirin to prevent cancer metastasis and the development of more effective drugs.
Cancer metastasis
Cancer metastasis, the process by which cancer cells spread from the primary tumor to other parts of the body, is a major challenge in cancer treatment. It is responsible for approximately 90% of cancer-related deaths, as once cancer spreads, it becomes much harder to treat effectively. The immune system plays a crucial role in fighting cancer, particularly when cancer cells are in their early stages of spreading. However, these cells often evade immune detection by creating an environment that suppresses the immune response.
How aspirin targets cancer spread
Previous studies have shown that daily low-dose aspirin reduces the spread of cancers such as breast, bowel, and prostate cancer. However, the exact mechanism remained unclear until now. The Cambridge team discovered that aspirin decreases the production of a clotting factor called thromboxane A2 (TXA2), which suppresses immune cells known as T cells. These T cells play a critical role in recognizing and killing cancer cells that break away from primary tumors and spread to other parts of the body.
The researchers found that TXA2 activates a protein called ARHGEF1, which suppresses T cells. By reducing TXA2 levels, aspirin releases T cells from this suppression, enabling them to attack metastatic cancer cells more effectively. In mouse models of melanoma, aspirin significantly reduced the frequency of metastases, demonstrating its potential to prevent cancer spread.
Professor Rahul Roychoudhuri, who led the study, explained: “When cancer first spreads, there’s a unique therapeutic window of opportunity when cancer cells are particularly vulnerable to immune attack. Targeting this window could prevent recurrence in patients with early-stage cancer.”
Aspirin’s potential in preventing cancer recurrence
The discovery has significant implications for ongoing clinical trials, such as the Add-Aspirin trial, which investigates whether aspirin can stop or delay early-stage cancers from returning. Dr. Jie Yang, a key researcher on the team, described the moment they identified TXA2 as a “Eureka moment,” noting that it opened up an entirely new avenue of research.
Aspirin’s affordability and accessibility make it a promising candidate for global use in cancer prevention. However, the researchers emphasize that aspirin is not without risks. In some individuals, it can cause serious side effects, including bleeding and stomach ulcers.
Professor Ruth Langley, who leads the Add-Aspirin trial, highlighted the importance of understanding which patients are most likely to benefit from aspirin. “This discovery will help us interpret clinical trial results and identify the right candidates for aspirin therapy,” she said. “However, patients should always consult their doctors before starting aspirin.”
The study was funded by the MRC, Wellcome Trust, and European Research Council, with additional support for the Add-Aspirin trial from Cancer Research UK, the National Institute for Health and Care Research, and the Tata Memorial Foundation of India.
As research continues, the findings offer hope for new strategies to prevent cancer metastasis and improve outcomes for patients worldwide.
The study is published in Nature
