Stress really does cause cancer - in fruit flies, at least - Yale researchers have discovered.
Both emotional and physical stress can trigger signals between cells that cause tumors to develop.
Until now, most researchers believed that there had to be more than one cancer-causing mutation in a single cell in order for tumors to grow. But the Yale team found that cancer-causing mutations can cooperate even from within different cells.
"The bad news is that it is much easier for a tissue to accumulate mutations in different cells than in the same cell," said Tian Xu, professor and vice chairman of genetics at Yale.
This cooperation turned out to be caused by a signaling process called JNK, which is activated by environmental stress conditions.
"A lot of different conditions can trigger stress signaling: physical stress, emotional stress, infections, inflammation – all these things," Xu said.
The good news is that it is possible to block these signals. "Better understanding of the underlying mechanism causing cancer always offers new tools to battle the disease," said Xu.
It's unclear how they triggered emotional stress in fruit flies - took away their bananas, possibly.