A drug commonly used to treat symptoms of Parkinson’s disease may have the capacity to stop pancreatic tumor cells from growing, reports a new study.
The current study stems from previous observations showing Parkinson’s patients seem to have a reduced incidence of cancer. Could this be because of the drugs that Parkinson’s patients take?
Common drugs prescribed to help Parkinson’s patients include carbidopa in conjunction with levodopa (L-Dopa). However, previous studies that looked into whether L-Dopa conferred anti-cancer effects did not find promising evidence.
This time, researchers from the Texas Tech University Health Sciences Center (TTUHSC) focused on carbidopa, hoping this is the drug behind the anti-cancer effects.
"Interestingly, no one has previously suspected carbidopa as a potential player in this phenomenon,” said Dr. Yangzom Bhutia, the study’s senior research author. "Carbidopa is never used by itself as a drug for any disease. But [...] we believe that the reduced incidence of most cancers in Parkinson's disease patients is due to carbidopa."
The team exposed carbidopa to human pancreatic cell lines, chosen specifically because of pancreatic cancer’s notorious reputation as one of the most ruthless killers. "Pancreatic cancer, especially the pancreatic ductal adenocarcinoma, is the most lethal of all cancers with a dismal survival rate,” said Dr. Bhutia.
With carbidopa treatment, the tumor cells were less able to form colonies, suggesting carbidopa slowed the cells’ ability to grow.
When the team tested carbidopa in a mouse model of pancreatic cancer, they observed similar promising results. Mice treated with carbidopa had smaller tumors, by volume and weight, as compared to the untreated mice.
The team also observed that carbidopa activated a protein, known as aryl hydrocarbon receptor (AhR), has been shown to have anti-cancer effects. In addition to the pancreatic cancer cell lines, activation of the AhR protein was seen in liver cancer cell lines. "Hence carbidopa could potentially be repurposed to treat pancreatic cancer and possibly other cancers as well,” the authors speculated.
"Carbidopa as an anti-cancer agent to treat pancreatic cancer would be something truly amazing. Given the fact that it is an FDA-approved drug, repurposing the same drug for cancer treatment would be tremendously cost- and time-saving,” Dr. Bhutia said. "Our laboratory is actively working to determine if there are additional targets for this drug related to its potency as an anti-cancer drug."
Of note, the most common type of pancreatic cancer is known as pancreatic ductal adenocarcinoma (PDAC). It accounts for a small percentage of all diagnosed cancer (around 3 percent), but claims an aggressive number of lives (around 7 percent of all cancer-related deaths in the US). It’s estimated that of the 53,000 Americans who will be diagnosed with pancreatic cancer this year, almost 79 percent will succumb from the disease.
Additional sources: MNT