URBANA, Ill. – Cancer: The word alone evokes dread, anxiety, and fear. Accordingly, many women living with the disease and undergoing treatment experience chronic stress and depression. Scientists have demonstrated, in studies with rodents and humans, that stress can exacerbate cancer’s progression, but it wasn’t clear how.

A new study, published in The Journal of Clinical Investigation, establishes that the stress hormone epinephrine sets off a cascade of biochemical reactions that favor breast cancer growth and spread.