Mouse Study Finds Heart's Mechanical Stress May Suppress Cancer Growth

A study published in Science on Thursday proposes that the constant mechanical pressure from the heart beating thousands of times a day and pushing gallons of blood creates an environment hostile to cancers. The research, led by Giulio Ciucci and Serena Zacchigna at the International Centre for Genetic Engineering and Biotechnology in Trieste, Italy, was conducted in mice.

@statnews reported that this could explain why heart disease and cancer are the leading causes of death in the United States, yet cancer rarely affects the heart.

To test the hypothesis, researchers transplanted a second heart into mice that was not pumping blood through the left ventricle. They then injected cancer cells into both hearts. Cancer spread quickly in the transplanted heart under less stress, but rarely spread in the native heart.

The research team found genetic differences between cancers that spread in the heart and those that did not. They identified a protein that senses mechanical forces and reduces the activity of genes linked to proliferation in cancer cells. @statnews reported that this link between mechanical load and epigenetic regulation shows physical forces can directly alter gene expression in cancer cells.

Michael Fradley, a professor of clinical medicine at University of Pennsylvania who was not involved with the study, said, 'It’s interesting that [cancer] doesn’t occur that often in the heart. People have not really been sure exactly why, but it’s just something that we accepted.

' Javid Moslehi, a cardiologist at the University of California, San Francisco who was not involved in the study, said, 'What’s really striking is this link they provide between mechanical load and epigenetic regulation.