Researchers Identify Possible New Approach to Treating Pancreatic Cancer
Pancreatic cancer treatments could become more effective through the help of a new strategy designed to target cancer cells while sparing the healthy ones.
Pancreatic cancer begins in the tissues of the pancreas and is an especially aggressive, deadly form of cancer. Rarely detected in its early stages, often signs and symptoms do not arise until the cancer is too advanced to be removed surgically. According to the National Cancer Institute, an estimated 45,220 new cases of the disease will arise in 2013, with some 38,460 deaths are expected to occur.
"To make things worse, pancreatic cancer is highly resistant to chemotherapy and radiotherapy," said Dr. Jason Bruce, from the University of Manchester. "Clearly a radical new approach to treatment is urgently required."
Published in The Journal of Biological Chemistry, the study found that pancreatic cancer cells may boast a specialized supply of energy responsible for maintaining the calcium levels that keep cancer cells alive.
If cells are to survive, they have to keep a low concentration of calcium. This is done with the help of a calcium pump, known as PMCA, that is fueled using adenosine triphosphate, or ATP.
Cells' energy comes from two major sources: mitochondria, which account for roughly 90 percent of a healthy cell's energy, and glycolysis. Pancreatic cells are different in that their major energy source switches over to the latter. The belief is that the the calcium pump may harbor its own glycolytic ATP supply that enables the cancer cells to survive better than the normal cells.
Using cells from human tumors, the researchers blocked the two energy sources in turn. When the mitochondrial metabolism was blocked, there was no effect. But when they blocked glycolysis, a reduced supply of ATP occurred, which in turn inhibited the calcium pump. As a result, the cells died from a calcium overload.
"It looks like glycolysis is the key process in providing ATP fuel for the calcium pump in pancreatic cancer cells," Bruce said. "Although an important strategy for cell survival, it may also be their major weakness."
Knowing this could mean an entirely new pathway of therapy, according to the scientist.
"Designing drugs to cut off this supply to the calcium pumps might be an effective strategy for selectively killing cancer cells while sparing normal cells within the pancreas."