Aspirin's cancer-fighting potential stems from its ability to decrease thromboxane A2 (TXA2) production, a clotting factor produced by platelets in the bloodstream12. TXA2 normally activates a protein called ARHGEF1 in T cells, suppressing their ability to identify and eliminate metastatic cancer cells3. By reducing TXA2 levels, aspirin effectively releases T cells from this suppression, enabling them to recognize and attack cancer cells before they establish metastatic tumors45. This mechanism was described as a "Eureka moment" by Dr. Jie Yang, one of the researchers at the University of Cambridge, as it unexpectedly revealed aspirin's role in enhancing the immune system's cancer-fighting capabilities67.

Researchers utilized a mouse model of melanoma to demonstrate aspirin's effectiveness in reducing cancer metastasis. Mice treated with aspirin exhibited significantly fewer metastases compared to control subjects, providing compelling evidence for the drug's anti-cancer properties12. This reduction in cancer spread was directly linked to aspirin's ability to prevent TXA2 from impairing T cell function, allowing these immune cells to more effectively recognize and eliminate metastatic cancer cells34. The experimental results highlight a critical "therapeutic window of opportunity" when cancer cells are particularly vulnerable to immune attack, as emphasized by Professor Rahul Roychoudhuri, who led the study5.

The Add-Aspirin clinical trial, a collaborative effort between researchers and Professor Ruth Langley at University College London, aims to determine if aspirin can stop or delay the recurrence of early-stage cancers1. This trial builds on previous large randomized controlled studies that unexpectedly found lower cancer mortality rates among daily aspirin users, with benefits emerging after just a few years of consumption2. The research could help identify specific cancer patients most likely to benefit from aspirin treatment, potentially offering a more affordable alternative to antibody-based therapies34. However, researchers caution that aspirin can cause serious side effects in some individuals, including bleeding and stomach ulcers, emphasizing the importance of consulting a doctor before starting any aspirin regimen5.

The discovery of aspirin's mechanism in preventing cancer metastasis opens up exciting possibilities for future cancer treatments. Researchers are exploring the potential of aspirin or other drugs targeting the TXA2 pathway as more affordable alternatives to antibody-based therapies, potentially making them more globally accessible12. This breakthrough could lead to the development of more targeted therapies to prevent cancer metastasis, which is responsible for approximately 90% of cancer-related deaths worldwide3. As the research progresses, it may pave the way for new strategies in cancer prevention and treatment, particularly in addressing the critical early stages of metastasis when cancer cells are most vulnerable to immune attack45.