Scientists find Alzheimer's Disease reduces human brain cancer growth

Sep 28 2010

Scientists at the Roskamp Institute in Sarasota, Florida, have shown that mice that naturally develop Alzheimer's are able to ward off the growth of brain cancer. In a series of experiments published in the Journal of Neuroscience, they showed that mice that spontaneously develop Alzheimer's Disease are able to dramatically reduce the growth of a human brain cancer. Brain cancers affect 612,000 people in the United States and are particularly common in children and older adults. 10,000 Americans are diagnosed each year with one of the most deadly brain tumors called malignant gliomas, the type of brain tumor tested in the study. Only about 50% of patients are alive 1 year after diagnosis, and 25% after two years despite surgical and medical treatment. Scientists believe that the cancers in the brains of the Alzheimer mice don't grow as they normally would because their blood supply is choked. It has long been known that in order to grow cancers need large blood supplies which they hijack from existing normal blood supplies. This is true of the brain cancers tested in the mice. In the normal mice without Alzheimer's Disease the cancers grew rapidly and aggressively in the brain as they do in humans. But in the mice with Alzheimer's Disease the brain cancers grew much more slowly and their blood supplies were greatly reduced. 

Dr Daniel Paris, lead author on the study paper: "We believe that the small protein that causes Alzheimer's Disease, called amyloid, stops cancer blood vessels growing and thus the supply of nutrients and oxygen to the cancer is stifled."

Studies of Alzheimer's Disease patients suggest that cancer rates may be lower than the general population which would be expected if amyloid can stop new blood vessel growth in cancers.

Dr Michael Mullan, Director of the Roskamp Institute: "We believe that small parts of the amyloid protein may be harnessed to bring about these beneficial effects against cancer while the negative effects (causing Alzheimer's Disease) are avoided."

The work was conducted in collaboration with a team led by Dr Steven Brem, neurosurgeon at the Moffitt Cancer center, Tampa.