Biomarker helps identify who might benefit from aspirin for colon cancer protection
Aspirin has been shown to prevent colon cancer, but researchers say protection is limited to individuals with a specific biomarker for inflammation and already at risk. The inflammatory marker, known as sTNFR-2, increased the chances of colon cancer 60 percent compared to individuals with lower levels.
Specific inflammatory marker linked to colorectal cancer
Investigators from Massachusetts General Hospital (MGH) and Dana-Farber Cancer Institute conducted the study that they say supports inflammation as a risk for cancer and other diseases - but not all inflammatory biomarkers predict who is at risk.
Andrew Chan, MD, MPH, of the MGH Gastrointestinal Unit, the paper's lead author says the new findings suggest the biomarker can show who would benefit from taking aspirin or NSAID's to prevent colon cancer and notes the complexity of inflammatory pathways in the body that lead to chronic disease and various types of cancer.
For the study, researchers used data from the Nurses Health Study that included 120,000 female registered nurses analyzing blood samples provided in 1989 or 1990. All of the nurses were cancer free at the time.
During the study 283 study participants developed colorectal cancer. The scientists matched those who developed the disease to 555 controls who were cancer free. They then analyzed baseline levels of three inflammatory factors – C-reactive protein (CRP), interleukin-6 (IL-6) and soluble tumor necrosis factor receptor-2 (sTNFR-2), finding the increased risk of colon cancer in association with with s TNFR-2, but not the other biomarkers.
Chan explains, "Our results suggest that, even though chronic inflammation may increase colorectal cancer risk, not all blood markers of inflammation are markers of that risk," says Chan. "The most common blood biomarkers of inflammation – CRP and IL-6 – do not appear to be relevant, while sTNFR-2 does. A better understanding of the significance of these markers will help us identify individuals most likely to benefit from chemoprevention using aspirin or NSAIDs."
The researchers also found aspirin and NSAID's protection from colorectal cancer was seen mostly among study participants with elevated levels of soluble tumor necrosis factor receptor.