Aspirin protects against colon cancer, Pitt study shows
Doctors have known for years that taking aspirin might reduce the risk of colon cancer by as much as 50 percent — they just didn’t know how the science works.
A study based at the University of Pittsburgh Cancer Institute has spotted a biological mechanism that could unravel the mystery, a discovery that might lead to better treatments with fewer side effects, researchers announced Monday.
The disease ranks as the second-leading cause of cancer-related fatalities nationwide and is projected to kill 50,000 people in 2014.
“If you can reduce the risk of colon cancer by significant fractions or (a small) percentage, that saves the lives of a lot of people,” said senior investigator Lin Zhang, an associate professor at the cancer institute and the Pitt School of Medicine.
His five-year collaboration with researchers at Pitt and two other schools shows that aspirin and other common painkillers such as ibuprofen can trigger self-destruction of cells that might lead to cancerous tumors. Their findings appear online in the Proceedings of the National Academy of Sciences, a research journal.
Zhang said researchers will use the information to try to refine preventive treatments for those at high risk of colon cancer. An estimated 136,830 people in the United States will be diagnosed this year, according to the American Cancer Society.
“Basically, you sort out the good things and hopefully mitigate the bad things. In that way, I think — hopefully — we’ll improve the preventive effects of those drugs,” Zhang said.
Chronic use of the painkillers reviewed in the study, known as nonsteroidal anti-inflammatory drugs, can cause dangerous complications, including gastrointestinal bleeding and ulcers.
Those side effects have long worried doctors, said Dr. Otis Brawley, chief medical officer at the American Cancer Society in Atlanta. He said people on aspirin therapy can bruise more easily and can have a higher chance of hemorrhagic stroke.
Still, a separate study in 2011 found that aspirin use cut the risk of cancer-related death by about 20 percent for participants in the research, according to the National Cancer Institute. The institute said several ongoing clinical trials are exploring aspirin’s effects on cancer risk in more detail.
“Given the fact that it decreases the risk of heart attack death, it’s an amazing substance,” Brawley said.
But people should rely on doctors’ recommendations before adopting an aspirin regimen, Zhang said.
He said $2 million to $3 million in funding from the National Institutes of Health helped finance his team’s latest work and related research. The American Cancer Society and Pitt assisted.
Adam Smeltz is a staff writer for Trib Total Media. He can be reached at 412-380-5676 or [email protected].