It is a popular saying that no matter what the symptoms, doctors will say: “Take two aspirin and go to bed.” Ironically, aspirin has come to play a role in prevention and cure of disease. Commonly recommended for prevention of stroke and heart attack, a highly publicized study in the Journal of the American Medical Association (JAMA) concludes that taking aspirin increases the survival rate among patients with colon cancer.
Description of the Study
Published in the August 2009 issue of JAMA, the study, “Aspirin Use and Survival After Diagnosis of Colorectal Cancer,” (Chan AT et. al.), a group of over twelve hundred people in various stages of colon cancer were followed for 11 years. Investigators hypothesized that aspirin could be a treatment for colon cancer.
History of Aspirin
Sunny Y. Auyang, in the article, “From experience to design – The science behind Aspirin,” (n.d.), says that white willow bark was prescribed for pain relief in Egyptian papyrus, the writings of Hippocrates, and in medieval medicine. By the late 1800s, salicylic acid had become a standard pain reliever.
A side effect of salicylic acid was stomach irritation. In 1897, Felix Hoffman, a German chemist, created a less-irritating medicine for his father, who was suffering from arthritis. What he developed was synthesized acetylsalicylic acid (ASA), called aspirin.
How Aspirin Works
The next challenge for scientists was to determine the exact mechanism by which aspirin provides pain relief. In 1966, John Vane won the Nobel Prize for answering this question (Auyang, SY. n.d.). Aspirin works by preventing the production of prostaglandins. Prostaglandins cause pain and inflammation by the action of an enzyme called COX. COX1 is actually beneficial to the body. It aids in blood coagulation and supports the mucus that coats the lining of the stomach. COX2 causes pain and inflammation. By inhibiting prostaglandins, aspirin has a triple effect:
- Aspirin fights pain and inflammation by blocking COX 2
- Aspirin thins the blood by inhibiting the clotting mechanism of COX1
- Aspirin prevents COX1 from protecting the gastric mucosa
Aspirin and the Risk of Heart Attack and Stroke
The effect of aspirin on the stomach was quickly recognized. Tylenol became popular and coated aspirin came into being. However, it was not until a special report in the January 28, 1988 issue of the NewEngland Journal of Medicine that aspirin’s ability to thin the blood was first recognized for its potential to reduce the risk of heart attack and stroke.
In spite of its side effects on the stomach, regular consumption of low-dose aspirin was recommended to prevent heart attack and stroke. The 2005 Nobel Prize winning discovery that peptic ulcers are caused by the bacteria H. pylori - and not stomach acid - further encouraged the regular use of aspirin.
How Aspirin Cures Colon Cancer
In the 2009 study (Chan et. al.), the effect of aspirin on the survival rate of patients with colon cancer was much greater among persons whose tumors produced excessive COX2. Aspirin was not as effective in other cases, but still showed a longer survival rate. The conclusion of the study was that consumption of aspirin increases the survival rate of individuals with colon cancer, and especially for those with COX2 producing tumors. The study supported the consumption of aspirin in all stages of established disease.
From Tree Bark to “Super Drug”
Learning how aspirin works increased knowledge of the both the side effects of aspirin, and resulted in the discovery of additional benefits of aspirin. John Vane won a Nobel Prize by answering the question, “how aspirin works.” It appears that he is winning that prize over and over again.
References:
“Aspirin Use and Survival After Diagnosis of Colorectal Cancer, “Chan, AT, Ogino, S, Fuchs, CS, JAMA. 2009;302(6):649-658.
Special Report on the “Physicians' HealthStudy,” NewEngland Journal of Medicine, Jan 28, 1988.
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