The internationally renowned academic journal Nature recently published a cancer research paper stating that aspirin may enhance the immune response against cancer metastasis in mice. This experimental study, which shows the potential of aspirin to limit cancer metastasis, may help develop effective anti metastatic immunotherapy. The paper introduces that cancer metastasis (the spread of cancer cells from the primary lesion to distant organs) is the culprit behind 90% of cancer-related deaths worldwide. The immune system plays an important role in combating metastasis, but cancer cells often manage to evade immune surveillance, one of which is by producing thromboxane A2 (TXA2) from platelets in the blood, thereby inhibiting the activity of T cells (an immune cell) at the site of metastasis. This inhibitory effect will hinder the immune system from effectively attacking and eliminating cancer cells in metastasis. Previously, it was found that aspirin was associated with reduced metastasis, but the exact mechanism of action was unclear. In this study, co corresponding author Rahul Roychoudhuri from the University of Cambridge in the UK, along with colleagues and collaborators, conducted experiments in mice and discovered a new immunosuppressive pathway. Aspirin can enhance the anti metastatic immune ability of mice targeting this pathway. They also found that compared with the untreated control group, the mouse models with a variety of different cancers (including breast cancer, melanoma and colon cancer) had lower rates of metastasis to other organs (such as lung and liver) after aspirin treatment. Aspirin is known to inhibit cyclooxygenase-1 (an enzyme involved in inflammation) in platelets and reduce TXA2 production. Research has found that the reduction of TXA2 alleviates T cell inhibition, thereby enhancing its ability to combat metastatic cancer cells. The authors of the paper summarize that this study suggests that aspirin may serve as a relatively inexpensive, low tech, and effective adjuvant therapy to prevent cancer metastasis by enhancing the natural immunity of mice. They believe that future research can explore the combination of aspirin and other immunotherapies to further enhance their anti metastatic effects. (New Society)