Scientists discover how aspirin could prevent cancer cells from spreading

Cancer remains one of the most devastating health challenges worldwide, with millions of people diagnosed every year. 

According to the World Health Organization, about one in five people develop cancer in their lifetime. Approximately one in nine men and one in 12 women die from the disease. Despite advancements in early detection and treatment, the spread of cancer cells continues to be the primary cause of death for most cancer patients. Now, researchers at the University of Cambridge may have uncovered a surprising way to do that — through a common, affordable drug: aspirin.

The study, published in Nature, explores how aspirin could stop metastasis—the spread of cancer cells from the original tumour to other organs—offering new hope for patients battling early-stage cancers.

Traditionally, cancer therapies have focused on either removing tumours surgically or using radiation and chemotherapy to kill cancer cells. However, despite these treatments, cancer often returns because micrometastases — tiny, dormant cancer cells that have already begun to spread — can evade detection and treatment. These cells can later activate, leading to recurrent and often more aggressive forms of cancer. The Cambridge team’s research has uncovered an unexpected mechanism by which aspirin could stop these early-stage cancer cells from developing into dangerous metastases.

The key discovery is the role aspirin plays in the body’s immune response to cancer. The research team found that aspirin works by targeting platelets, the cells responsible for blood clotting. When cancer cells begin to spread, platelets release a substance known as thromboxane A2 (TXA2), which suppresses the body’s immune T cells—the fighters tasked with destroying cancerous cells.

The breakthrough was made while studying melanoma, an aggressive form of skin cancer. In the study, mice treated with aspirin developed fewer metastases compared to control groups. “Aspirin worked as a switch, reactivating the body’s immune system to target and kill cancer cells,” said Prof Rahul Roychoudhuri, a lead author of the study. 

The discovery also highlights what scientists call a “therapeutic window” — a crucial period when cancer cells are particularly vulnerable to immune attacks after spreading from their original tumour site. “When cancer cells first begin to spread, they are at their weakest. This window of vulnerability is a key opportunity to stop metastasis before it fully takes hold,” said Prof Roychoudhuri.

In the study, the researchers focused on early-stage cancers that have a high risk of recurrence. The findings suggest that targeting this vulnerable phase with aspirin or similar drugs could dramatically reduce the risk of cancer metastasis and recurrence, potentially changing the way we treat cancer in its early stages.

“Aspirin inhibits the production of TXA2, essentially freeing the T cells from suppression, allowing them to target and eliminate the rogue cancer cells,” explained Dr Jie Yang, a co-author of the study. “It was a eureka moment when we found that TXA2 was the molecular signal responsible for this suppressive effect. This discovery opens up new avenues for therapies that could prevent the spread of cancer."

Unlike more expensive cancer therapies such as antibody-based immunotherapies, the researchers say that aspirin is cheap and widely available. 

“Aspirin could provide a low-cost alternative to prevent metastasis, especially in the early stages of cancer. This could significantly impact global cancer survival rates,” Dr Yang added.

However, despite the promising findings, researchers caution that aspirin is not a universal solution and may not be suitable for everyone. Like any drug, aspirin comes with risks and potential side effects, including stomach ulcers, bleeding, and digestive issues, particularly when taken long-term.

Further research is needed to determine the precise conditions under which aspirin may be effective in preventing cancer recurrence and metastasis. 

Lnjeru@ke.nationmedia.com