Phil Mickelson's wife diagnosed with breast cancer

Certain changes in DNA can cause normal breast cells to become cancerous. DNA is the chemical in each of our cells that makes up our genes -- the instructions for how our cells work. Some inherited DNA changes can increase the risk for developing cancer and are responsible for the cancers that run in some families.

Mickelson's wife, Amy, has been diagnosed with breast cancer, and the three-time major champion said Wednesday he will suspend his PGA Tour schedule indefinitely.

Mickelson, the No. 2 player in the world with 36 career PGA Tour victories, was to play in the Byron Nelson Championship this week before defending his title next week at Colonial. It was not certain if he would return in time for the U.S. Open from June 18-21 in New York, where he was the runner-up to Tiger Woods in 2002 and is beloved by golf fans

According to a release from Mickelson's management company, his wife was to have more tests but begin treatment with major surgery as early as the next two weeks.

Stress worsens cancer

Stress can lower the body’s ability to do the immune system dan DNA cannot repair the abnormal cells. People who are in acute stress have been shown to have a reduction in immune function.

Stress hormones attach directly to tumour cells and stimulate new blood vessel growth and other factors that lead to faster and more aggressive tumours, the researchers said

Dr Anil Sood of The University of Texas M.D. Anderson Cancer Centre and colleagues noticed that ovarian cancer patients who reported high levels of stress in their lives also had higher levels of a protein called VEGF, which stimulates blood vessel growth in tumours. Patients who had more social support in their lives had lower levels of VEGF.

So the team infected mice with ovarian cancer and then stressed some by confining them alone in a small space for two or six hours. Mice stressed for six hours had 3.6 times as many tumours. And in half the stressed mice the tumours had already spread to the liver or spleen.