Previous studies suggested a connection between aspirin use and improved cancer survival rates. A study published in Nature last week explains the underlying reasons for this connection. Nonetheless, experts emphasize that aspirin is not a cure and comes with risks such as an increased potential for internal bleeding.
So, how does aspirin potentially halt the spread of cancer? And what implications does this have for future treatments?
What have studies found about aspirin use and cancer?
Recent studies indicate that aspirin, a widely used painkiller, might help prevent the spread of cancer, although its effectiveness across all types of cancer remains unclear.
The first clinical study, published in 1988, showed that regular aspirin use significantly lowered the risk of colorectal cancer, but the underlying reasons were unclear.
Now, research from the University of Cambridge offers more insight. This study identifies the mechanism by which aspirin may help prevent cancer from spreading, a process known as metastasis.
Metastasis is responsible for the majority of cancer-related deaths, as cancer cells break away from the original tumor and attempt to establish themselves in other parts of the body.
As these errant cancer cells turn rogue, aspirin may enhance the body’s natural defense mechanisms, preventing the cancer cells from colonizing more organs.
How can aspirin keep cancer from spreading?
The key to aspirin’s effect on cancer lies within the body’s immune system, a complex network of cells and proteins that defend against infections, diseases, and harmful germs.
When cancer cells detach from a tumor, they enter the bloodstream, where the immune system – specifically types of white blood cells known as T-cells – normally locates and destroys them. However, platelets – tiny cell fragments in the blood that assist with clotting – can interfere with this process.
Cancer exploits platelets by triggering a response similar to an injury. When platelets detect these free-floating cancer cells, they rush to coat them, resembling how they would cover a wound to stop bleeding.
This creates a protective shield, making it harder for the immune system to recognize and attack the cancer cells. Additionally, platelets release signals that suppress T-cells, hindering their ability to function.
Aspirin disrupts cancer’s attempts at deception by reducing the production of a molecule that platelets use to suppress immune activity. With the platelets weakened, T-cells regain their ability to recognize and destroy cancer cells before they have a chance to form new tumors.
How could aspirin be used against cancer?
The study suggests that aspirin could be used after treatments like surgery, where tumors are removed.
This is significant because some cancer cells may have already escaped from the tumor and begun to settle in other parts of the body, a process known as seeding, where tiny cancer cells embed themselves in new areas and may later grow into tumors.
However, experts warn against immediately using aspirin as a cancer treatment without further research. The painkiller carries the potential for serious side effects, such as internal bleeding, because by weakening the platelets, it can diminish their ability to help blood clot.
Aspirin blocks a molecule that prompts platelets to clump together. This makes the blood thinner and increases the risk of uncontrolled bleeding, which is especially dangerous in the stomach and brain.
Additionally, the study was conducted on mice, not humans, so its effects on cancer spread still need to be confirmed before it can be recommended for treatment.
“Our research provides a molecular explanation for observations from clinical studies, but proper clinical validation is still needed,” Rahul Roychoudhuri, a professor in Cambridge’s Department of Pathology involved in the Nature study, told Al Jazeera.
Several clinical trials are underway to determine which patients are most likely to benefit from taking aspirin and whether it is effective for specific types of cancers.
Roychoudhuri added that he does not anticipate an “immediate fast-tracked translation” of aspirin to cancer treatment.
Has aspirin been used against diseases in the past?
Some patients with a high genetic risk for cancer, such as those with Lynch syndrome (a condition that increases the likelihood of developing certain cancers), are already advised to take aspirin as a preventive measure in countries like Australia and the UK.
Since the 1980s, aspirin has also been prescribed to help prevent heart attacks and strokes in people at high risk of heart disease, by reducing the ability of platelets to form harmful clots that can block blood flow to the heart or brain.
Does this mean we are close to a breakthrough in curing cancer?
Not necessarily. While aspirin may help slow or prevent the spread of cancer, it does not eliminate tumors entirely.
However, scientists are working to identify biomarkers and platelet activity to help detect individuals at risk for cancer early on.
“This would allow for timely treatment with aspirin while minimizing unnecessary exposure for those who do not require it,” said Paola Patrignani, a professor of pharmacology at Gabriele d’Annunzio University in Italy.
Experts say the findings could contribute to the development of drugs that inhibit cancer spread.
“Our discoveries open possibilities for developing more targeted therapies that could potentially provide the benefits without aspirin’s side effects,” Roychoudhuri said.
Patrignani, who is involved in research funded by Cancer Research UK to investigate whether other anti-platelet drugs might offer similar benefits, says these studies will require another three to five years to be completed.
However, she is optimistic about the direction of the research. “We are on the verge of a significant breakthrough in cancer research. This newfound knowledge could pave the way for innovative treatments and potentially save countless lives.”
Why does a cure for cancer remain so elusive?
Finding a cure for cancer remains one of the greatest challenges in medicine.
As there are many different types of cancer, each with its own characteristics and ways of spreading, it is difficult to develop a universal cure.
Additionally, tumor development is influenced by a combination of genetic predisposition and environmental factors. Studies suggest that treatment must be personalized to be truly effective.
Many cancers also develop ways to hide from or suppress the immune system, making them harder to attack even with immunotherapy.
Source: https://www.aljazeera.com/news/2025/3/15/can-an-aspirin-a-day-keep-cancer-away?traffic_source=rss
