An experimental cancer drug appears to help regenerate damaged heart muscle — an unexpected finding that may help prevent congestive heart failure.

The findings from UT Southwestern Medical Center were published recently in Proceedings of the National Academy of Sciences.

Many parts of the body, such as blood cells and the lining of the gut, renew continuously while others, such as the heart, do not. Because the heart can’t repair itself, damage from a heart attack causes permanent scarring that frequently results in serious weakening of the heart.

Lawrence Lum, Ph.D., senior author of the study and an associate professor of cell biology at UT Southwestern, has worked to develop a cancer drug targeting signaling molecules that are crucial for tissue regeneration, but also frequently contribute to cancer.

Researchers induced heart attacks in mice and then treated them with a so-called porcupine inhibitor. Their hearts’ ability to pump blood improved by nearly two-fold compared to untreated mice, a finding the researchers called “striking.”

“We saw many predictable adverse effects — in bone and hair, for example — but one surprise was that the number of dividing [heart muscle cells] was slightly increased,” Lum said in a news release.

The researchers also noticed a reduction in fibrosis, or scarring in the hearts. Such scarring that occurs after a heart attack can cause the heart to increase in size and lead to heart failure.

Preliminary experiments show that the porcupine inhibitor would only need to be used for a short time after a heart attack, suggesting that the common side effects of cancer drugs might be avoided.

Lum said they plan to test a Porcn inhibitor in humans as a regenerative agent for heart disease within the next year.