BOSTON — New research published in the October 2011 issue of Harvard Men's Health Watch suggested aspirin may play a role in fighting cancer, the publication announced Wednesday.
Aspirin inhibits the action of two enzymes in the body — cox-1 and cox-2. One of these, cox-2, triggers the production of chemicals that cause fever, create inflammation in joints and other tissues and aggravate pain. Research suggests that these same cox-2 enzymes may have a role in certain cancers. Cox-2 appears to promote the growth of new blood vessels to support the rapid growth of tumors, and also may interact with various growth factors to stimulate the multiplication of malignant cells. It also appears to inhibit apoptosis, a natural defense mechanism that helps prevent runaway tumor growth by triggering cell death by suicide.
The information about cox-2 inhibitors and human cancer still is under study, but scientists have discovered that many of the most aggressive colon cancers have unusually high levels of cox-2, as do many prostate cancers. In addition, randomized clinical trials have demonstrated that cox-2 inhibitors help prevent people at high risk of colon cancer from producing the benign polyps that give rise to nearly all colon cancers.
A British study analyzed fully completed, high-quality randomized trials of aspirin. When analyzed together, these trials showed that daily aspirin reduced the risk of dying from cancer by 21%. Seven-of-the-8 trials provided enough information to permit analysis of individual patients and specific cancers. Aspirin was most effective against gastrointestinal cancers, reducing the risk of death by 54%.
It’s too soon to recommend routine aspirin use to prevent cancer, stated Harvard Men’s Health Watch. But people at high risk of cancer, particularly colon cancer patients, people with colonic adenomas and individuals with a strong family history of colon cancer, should discuss the issue with their doctors.
Though not included in the Harvard Men's Health Watch report, other over-the-counter medicines that also inhibit the cox-2 enzyme include ibuprofen (Advil, Motrin) and naproxen (Aleve). Prescription-only cox-2 inhibitors include Celebrex (celecoxib) and the older pain reliever Mobic (meloxicam).