TUESDAY, Aug. 18, 2009 (HealthDay News) -- Prion, an abnormal protein, is a biomarker of early pancreatic cancer, a new study suggests.
Prion accumulation causes mad cow disease, but very little is known about prions outside of the brain. This study identified the mechanism by which prions cause pancreatic tumors to grow more aggressively, said researchers at Case Western Reserve University School of Medicine in Cleveland.
They found that prion is incompletely processed in pancreatic cancer cells and binds to a molecule inside the cells called filamin A, which is a regulator of the cell's skeleton and its signaling machineries. By binding to filamin A, incompletely processed prion disrupts the tumor cells' organization and signaling, causing more aggressive cancer growth.
When the prion level is reduced, the cancer cell loses the ability to grow in tissue culture and in animals.
The researchers also found that patients with incompletely processed prion protein in their pancreatic cancer had significantly shorter survival than patients whose tumors didn't have prion.
"Currently, there is no early diagnostic marker for pancreatic cancer. Detection of the incompletely processed prion may provide such a marker. Preventing the binding of prion to filamin A may open new avenues for therapeutic intervention of this deadly disease," study co-author Man-Sun Sy, professor of pathology, said in a university news release.
The study appears in the September issue of the Journal of Clinical Investigation.
The U.S. National Cancer Institute has more about pancreatic cancer.