Cancerous signs have been discovered in atherosclerosis, which opens up new treatment options

Researchers have found that smooth muscle cells lining the arteries of people with atherosclerosis can develop into new cell types and take on cancer-like features, making the disease worse. The study was published in the magazine Circulation.

Atherosclerosis is characterized by narrowing of artery walls and may increase the risk of developing coronary heart disease, stroke, peripheral arterial disease or kidney disease. These findings, supported by the National Institutes of Health (NIH), may pave the way for the use of anticancer drugs to counter the tumor mechanisms that lead to plaque formation in the arteries, a leading cause of cardiovascular disease.

“This discovery opens an entirely new dimension in our understanding of therapeutic strategies for preventing and treating atherosclerosis,” said Ahmed Hasan, MD, program director of the Division of Cardiovascular Sciences at the National Heart, Lung, and Blood Institute, which is part of NIH.

“Previous studies have suggested that atherosclerosis and cancer may have some similarities, but this relationship has not been fully described until now.”

Using a combination of molecular techniques in mouse models and tissue samples taken from patients with atherosclerosis, researchers have characterized the molecular mechanisms that lead to the transition of smooth muscle cells into cancer-like cell types.

Researchers found increased levels of DNA damage and genomic instability—two hallmarks of cancer—in transformed smooth muscle cells from atherosclerotic plaques compared with healthy tissue. Genomic instability is an increased tendency for DNA mutations and other genetic changes during cell division.

Exploring further, they also found that genes associated with cancer became more active as smooth muscle cells were reprogrammed into the cells that make up the plaque. Using a mouse model with a known cancer mutation accelerated reprogramming and worsened atherosclerosis. Finally, treating atherosclerotic mice with the anticancer drug niraparib, which targets DNA damage, showed potential for preventing and treating atherosclerosis.

Atherosclerosis is a disease of the cardiovascular system. If it affects the coronary arteries (which supply the heart), it can lead to angina or, in worse cases, a heart attack. Source: Wikipedia/CC BY 3.0

“What we actually saw was that niraparib actually reduced atherosclerotic plaque in mice,” said Huise Pan, PhD, assistant professor of medicine at Vanderbilt University Medical Center in Nashville, Tennessee, and first author of the study.

Muredah Reilly, MD, professor of medicine at Columbia University in New York and senior author of the study, explained that understanding the molecular mechanisms leading to smooth muscle cell transition may provide opportunities to disrupt tumor pathways and change cell behavior. Which, in turn, can prevent or slow the progression of atherosclerosis.