A new study recently published in the Journal of Clinical Oncology revealed that aspirin may reduce the risk of cancer development in obese patients. The study was developed by an international research team led by researchers at the University of Leeds and Newcastle University in the United Kingdom, and is entitled “Obesity, Aspirin, and Risk of Colorectal Cancer in Carriers of Hereditary Colorectal Cancer: A Prospective Investigation in the CAPP2 Study.”
It is known that obesity causes a systemic inflammatory state in the body being associated with the development of several disorders including heart disease, type 2 diabetes and certain types of cancer such as colorectal cancer. The impact of obesity in patients with hereditary colorectal cancer, however, is not clear.
In the study, researchers investigated the possible link between the body mass index (BMI) and cancer risk in patients with Lynch syndrome, an inherited disorder characterized by the increased risk of developing several types of cancer, especially colorectal cancer due to defects on genes involved in the detection and damage repair in the DNA. In total, 937 Lynch syndrome patients were randomly assigned to receive aspirin 600 mg per day or a placebo, plus resistant starch 30 g per day or a placebo for a period of two years.
Researchers found that ten years after the intervention 55 patients of the cohort had developed bowel cancers. Furthermore, the team reported that Lynch syndrome patients who were obese had more than twice the likelihood of developing colorectal cancer, and that this risk increased with the BMI. Interestingly, obese Lynch syndrome patients with mutations in the MLH1 gene (which is associated with colon cancer development) were found to be at a 3.72 greater risk for developing colorectal cancer than normal-weight patients, suggesting that obesity potentiates the risk for cancer development in individuals who are already predispose to the condition. Remarkably, the team found that the cancer risk in overweight patients with Lynch syndrome could be reduced through a regular dose of aspirin.
“For those with Lynch Syndrome, we found that every unit of BMI above what is considered healthy increased the risk of bowel cancer by 7%. What is surprising is that even in people with a genetic predisposition for cancer, obesity is also a driver of the disease. Indeed, the obesity-associated risk was twice as great for people with Lynch Syndrome as for the general population.” explained the study’s senior author Dr. John Mathers in a news release. “The lesson for all of us is that everyone should try to maintain a healthy weight and for those already obese the best thing is to lose weight. However, for many patients this can be very difficult so a simple aspirin may be able to help this group.”
The research team concluded that obesity is strongly linked to an increased risk of colorectal cancer in patients with Lynch syndrome, and that this high risk can be abolished by regular aspirin administration.
“This is important for people with Lynch Syndrome but affects the rest of us too. Lots of people struggle with their weight and this suggests the extra cancer risk can be cancelled by taking an aspirin,” noted the study’s co-author Professor Sir John Burn. “This research adds to the growing body of evidence which links an increased inflammatory process to an increased risk of cancer. Obesity increases the inflammatory response. One explanation for our findings is that the aspirin may be suppressing that inflammation which opens up new avenues of research into the cause of cancer.”
The team also suggests that aspirin may enhance programmed cell death in pre-cancerous cells, consequently reducing cancer development. “We may be seeing a mechanism in humans whereby aspirin is encouraging genetically damaged stem cells to undergo programmed cell death, this would have an impact on cancer” said Sir Burn. However, he advises “Before anyone begins to take aspirin on a regular basis they should consult their doctor as aspirin is known to bring with it a risk of stomach complaints including ulcers. (…) But if there is a strong family history of cancer then people may want to weigh up the cost-benefits particularly as these days drugs which block acid production in the stomach are available over the counter.”
“Our study suggests that the daily aspirin dose of 600 mg per day removed the majority of the increased risk associated with higher BMI. However, this needs to be shown in a further study to confirm the extent of the protective power of the aspirin with respect to BMI” concluded the study’s co-author Dr. Tim Bishop. The research team is currently planning a large-scale follow-up trial with 3,000 people worldwide to evaluate the protective effects of different aspirin doses.