Popular statin drugs widely used to lower cholesterol to prevent heart disease apparently do not reduce the risk of cancer, despite a flurry of recent studies suggesting a strong anti-cancer benefit, two scientific investigations report today.
Statins are the most commonly prescribed medications in the United States and include Lipitor, Zocor, Mevacor, Crestor, Pravachol and Lescol.
For years, evidence has mounted from a series of smaller studies that have suggested statins dramatically reduce the risk of many common forms of cancer, mostly through their powerful anti-inflammatory activity.
But when two separate teams of scientists further scrutinized whether statins could beat back the risk of cancer, they concluded that excitement over the drugs for that reason might be premature.
"Statins do tons of things all over the body," said C. Michael White, a professor of pharmacy at the University of Connecticut at Storrs, whose analysis on statins' effect on cancer risk is reported in today's issue of the Journal of the American Medical Assn.
He added that statins had properties that might influence cancer development, just as they possessed anti-inflammatory activity that might prevent the genesis of a tumor.
"When viewed together, these positive and negative effects cancel each other out," White said. Among statins' negative properties, White pointed to their tendency to decrease the body's population of natural killer cells, immune system constituents capable of quashing early cancers.
"We were very hopeful that we would verify there was an anti-cancer effect," White said. "We ended up showing no change in cancer or cancer death."
He said his study, along with another reported in today's Journal of the National Cancer Institute, has provided enough evidence to stop further pursuit of statins as cancer-prevention agents.
"Both of these studies together answer a lot of questions," he said.
Hope for statins as cancer fighters was sharpened by the fact that so many people already take the drugs to lower cholesterol and that the drugs are considered safe.
Previous research, including animal studies and observational studies of people, had suggested statins might prevent various types of cancer.