Aspirin ‘could help immune system fight cancer’

    4 September 2015

    Researchers at the Francis Crick Institute have made a discovery that they say could boost the power of immunotherapy treatments, which are designed to improve the body’s capacity to fight cancer.

    Professor Reis e Sousa looked more closely at the chemical signal prostaglandin E2, which has the ability to put a particular type of immune cell ‘to sleep’. This safety mechanism prevents the immune system from overreacting to threats. The researchers say that its ability to suppress cell activity makes prostaglandin E2 ‘an important player in cancer’.

    The molecular machines which produce it — cyclo-oxygenase 1 and 2 — are unusually prevalent in breast, lung and bowel cancer patients. The researchers investigated the possibility that prostaglandin E2, or the cells that produce it, could be possible targets for treating cancer.

    By identifying the chemical signal in cancerous skin call samples, and then ‘editing out’ the cyclo-oxygenase genes in the melanoma cells, they removed the cell’s ability to create prostaglandin E2. As a result the cancer cells lost their ability to suppress the immune system response.

    Aspirin works by targeting these genes. Trials on mice by Professor Reis e Sousa have shown that test subjects treated with aspirin, alongside a new class of immunotherapy treatment known as a checkpoint inhibitor, were cured much more quickly than those receiving immunotherapy alone.

    The researchers claim that following their experiments, the subject mice became ‘cancer-proof’, and were able to recognise and eliminate the same type of cancer cells months after the tests.

    Even more excitingly, the animals became ‘cancer-proof’: they developed a strong immune ‘memory’, and their immune cells recognised and immediately destroyed the same type of cancer cells, even months after the first experiment.

    Despite these encouraging results, Cancer Research urges caution.

    ‘Although aspirin might seem like a commonplace ‘harmless’ drug, it can have serious side effects in some people, including strokes and internal bleeding. If you’re considering taking aspirin alongside cancer treatment, or on a regular basis, you should talk to your doctor first.’