Researchers have discovered that a drug already approved by the Food and Drug Administration (FDA) to treat cancer may hold the key to successfully combating Parkinson’s disease. This is welcome news as Parkinson’s disease cases are expected to rise by 60% in the U.S., according to the National Institute of Neurological Disorders and Stroke. There is currently no cure for the devastating disease.

In healthy brains, alpha-synuclein aids nerve cell communication, but in Parkinson’s disease the protein misfolds and clumps together to disrupt normal brain function. Alpha-synuclein proteins are the hallmarks of Parkinson’s disease A surface protein on brain cells, called Aplp1, is involved in spreading alpha-synuclein from cell to cell, according to ScienceAlert. Scientists believe that by taming that action, they may be able to slow down the progression of Parkinson’s disease.

A progressive neurodegenerative disorder, Parkinson's disease has long challenged scientists and clinicians alike. Characterized by symptoms such as tremors, rigidity, and slowed movements, it profoundly impacts the quality of life for millions worldwide. Now, emerging research surrounding the protein Aplp1 has opened a promising doorway toward understanding and managing this elusive disease.

In studies with genetically engineered mice, researchers at Johns Hopkins Medicine found that Aplp1 connects with Lag3, another cell receptor, to spread the harmful alpha-synuclein proteins to brain cells.

Lag3 is already the target of the combination cancer drug, nivolumab and relatlimab (Opdualag), which was approved in 2022 for cancer treatment, that teaches the human immune system how to seek and destroy its enemies.

“Now that we know how Aplp1 and Lag3 interact, we have a new way of understanding how alpha-synuclein contributes to the disease progression of Parkinson’s disease,” says Xiaobo Mao, associate professor of neurology at the Johns Hopkins University School of Medicine and a member of the Institute for Cell Engineering. “Our findings also suggest that targeting this interaction with drugs could significantly slow the progression of Parkinson’s disease and other neurodegenerative diseases.”

The researchers say that the Lag3 antibody cancer drug Opdualag could play a role in preventing cells from absorbing alpha-synuclein, according to Johns Hopkins Medicine. The findings of the study appeared in Nature Communications.

This research has potential applications in treating other neurodegenerative conditions that have no cures, Mao says. In Alzheimer’s research, for example, Mao says scientists could try to target Lag3 — which also binds with the dementia-related tau protein — with the same antibody.