The adrenal glands, which sit on the kidneys, produce epinephrine, also known as adrenaline. The body uses this hormone like a power tool at times of stress, but when stress is prolonged, the adrenals continue to pump out the hormone and levels remain elevated. Wondering how the excess epinephrine affects cancer cells, and by what process, researchers exposed breast and prostate cancer cells to the hormone in the lab. What's supposed to happen in the body, normally, is that a protein with the peculiar name of "BAD" helps trigger naturally occurring cell death, called apoptosis -- but when epinephrine comes into contact with BAD, as the researchers discovered, it activates enzymes that inactivate BAD and the cells continue to grow.
This might be one way high stress connects to cancer... unchecked by BAD, the cancerous cells continue on their destructive path. This discovery could help explain a previous Canadian study's finding that men who had taken beta blocker drugs for hypertension for at least four years had an 18% lower risk of developing prostate cancer... since beta blockers block the effects of epinephrine. Also, even more recently, another study published in the Journal of Psychosomatic Research, demonstrated that in patients with metastatic breast cancer, stressful or traumatic life events reduced the "median disease-free interval" to 30 months from 62.
INSIGHTS FROM THE RESEARCH TEAM
George Kulik, PhD, was one of the study's lead authors. When I called him he told me that not all types of cancer cells respond this way to stress hormones, so one priority is identifying which ones do. One reason past studies on stress and cancer have not been able to show a relationship could be because not all cancers are shown to react to epinephrine and Dr. Kulik suspects only 5% to 10% may be affected by the hormone. Dr. Kulik explained that in a large population study, these would be "washed out" in the overall findings. But once researchers know which cancer cells respond, they will have the opportunity to study them more closely.
WHAT CAUSES WHAT?
In some ways it almost seems like a bad joke -- a cancer diagnosis is highly stressful for anyone to have and obviously a time that stress hormones are likely to soar. It's not known whether epinephrine has an impact on the development of cancerous cells but, according to Dr. Kulik, the presence of stress hormones might interfere with cancer care because treatment is designed to trigger apoptosis of the diseased cells. Dr. Kulik and his colleagues are now working to learn more about the impact of stress hormones on individual patients, which he says will be aided by the fact that it is already possible to identify the level of stress hormones people have.
His team has now moved from experiments in the lab to doing them with mice. However, there is no reason to wait to develop better awareness of personal stress levels and to build an arsenal of tools to handle stress more successfully. Immediate responses to the acute stress of, say, receiving disappointing news or being anxious about a big event should include deep breathing, quiet music and other practices that are instantly soothing. For longer-term stress, such as day-to-day parenting challenges, a difficult job situation, or, for that matter, a cancer diagnosis, it is useful to develop stress management skills, which may include meditation, self-hypnosis, exercise and other techniques that calm the mind and the body. You can learn these in formal classes frequently found at community centers, YMCAs and the like, but there are also many books and CDs that are extremely helpful in practicing these techniques at home. Since stress has certainly been linked to other diseases as well, you can't lose by focusing on managing your stress.
George Kulik, PhD, assistant professor of cancer biology, Wake Forest University School of Medicine, Winston-Salem, North Carolina.