Their findings could lead to new therapies to treat or prevent heart disease - a leading cause of death in North America - as well as answer key questions about other diseases associated with high cholesterol levels, including some types of cancer.

The study is published in an early online edition of the Journal of Cell Science (http://jcs.biologists.org).

"We believe these findings represent a significant and novel breakthrough in cardiovascular research," said Jung San Huang, Ph.D., professor of biochemistry and molecular biology at the Saint Louis University School of Medicine and the study's lead researcher.

"This study gives us new insight into how cholesterol promotes atherosclerosis - and in turn, how it leads to heart attack and stroke," Dr. Huang added. "This could give us important new tools in the fight against heart disease."

It has long been known that high blood cholesterol is a key risk factor for developing atherosclerosis - sometimes called hardening of the arteries. The condition causes the arteries of the heart and other tissues to become damaged and narrowed, preventing blood from pumping through as it should and increasing the risk of heart attack and stroke.

Until now, however, the process by which cholesterol contributes to atherosclerosis has not been well understood.

The findings suggest answers to questions about other diseases associated with high blood cholesterol levels, including cancer. For example, why are patients with high cholesterol also prone to develop cancer? And why does drug therapy to lower blood cholesterol correlate with a lower incidence of some cancers, as has been previously reported?

The study, carried out over two years, was supported by grants from the National Institutes of Health, by Research to Prevent Blindness and by the Norman J. Stupp Charitable Trust.

A balanced diet and adequate daily exercise are still the most effective modes of prevention to curb heart disease and cancer, and these findings could certainly lead to further research to reinforce the postive impact of healthy lifestyles.