Cancer and Alzheimer’s disease are two of the most common illnesses that affect older adults.
But for years, doctors have noticed something surprising: people who survive cancer seem to be less likely to develop Alzheimer’s.
This strange connection has shown up in studies for quite some time, but no one really knew why it was happening—until now.
A new study from scientists in China may have found the answer. Researchers at the Huazhong University of Science and Technology looked closely at this relationship and made a breakthrough discovery. Their research was published in the journal Cell.
In Alzheimer’s disease, a protein called amyloid-beta builds up in the brain and sticks together to form clumps known as plaques. These plaques disrupt how brain cells talk to each other and are one of the main causes of memory loss and confusion in people with Alzheimer’s.
Current medications often try to stop new damage from happening, but they don’t do a good job of cleaning up the plaques that are already there.
The scientists wondered if something in cancer might help remove these harmful plaques. To test this, they used mice that had been specially bred to develop Alzheimer’s disease. Then, they gave these mice different types of cancer, including lung, colon, and prostate cancer. What they saw was remarkable: the plaques in the brains of these mice got smaller.
To understand how this was happening, the team studied the proteins that the cancer cells were releasing into the body. They found one protein in particular that seemed to be making the difference. It’s called Cystatin-C, or Cyst-C for short.
This protein entered the bloodstream and was able to cross the blood-brain barrier—a protective wall that usually keeps harmful substances out of the brain.
Once inside the brain, Cyst-C connected with toxic clumps of amyloid-beta and also interacted with microglia. These are special immune cells in the brain that normally help defend it. The Cyst-C protein helped activate these cells so they could start breaking down the plaques.
To see whether this helped the mice think better, the researchers gave them a memory test. In the test, the mice had to find a hidden platform in a pool of water—a task that requires memory and learning.
Before the treatment, the Alzheimer’s mice had trouble completing the task. But after being treated with either the purified Cyst-C protein or proteins from the cancer cells, the mice did much better. They remembered where the platform was and escaped the water more quickly.
This study is exciting because it shows a new way to treat Alzheimer’s. Instead of just trying to prevent damage, scientists might be able to use proteins like Cyst-C to actually clean up the damage that’s already been done. This could offer real hope to people who are already showing signs of memory loss.
The lead researcher, Youming Lu, said that these results give us a new way to think about treating Alzheimer’s. Instead of only lowering the levels of amyloid-beta, we might be able to break apart the plaques that are already there.
While more research is needed to see if this works in humans, the findings open up a new path for Alzheimer’s treatment—and give scientists one more reason to keep exploring the surprising connection between cancer and brain health.
If you care about Alzheimer’s, please read studies about the likely cause of Alzheimer’s disease , and new non-drug treatment that could help prevent Alzheimer’s.
For more health information, please see recent studies about diet that may help prevent Alzheimer’s, and results showing some dementia cases could be prevented by changing these 12 things.
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