Heartbeats may keep heart cancers rare, study suggests

New research suggests the heart’s rhythmic beating creates mechanical strain that suppresses cancer growth in heart tissue. In mouse experiments, non‑beating transplanted hearts rapidly developed cancer, while beating native hearts largely resisted it and restricted cancer to the outer layers; engineered heart tissue that beat only when stimulated with calcium showed a similar pattern. This mechanical effect could help explain why heart tumors are extraordinarily rare in mammals.