Reporting on a small preliminary study, Johns Hopkins researchers say a simple blood test based on detection of tiny epigenetic alterations may reveal the earliest signs of pancreatic cancer, a disease that is nearly always fatal because it isn't usually discovered until it has spread to other parts of the body.
The findings of their research, if confirmed, they say, could be an important step in reducing mortality from the cancer, which has an overall five-year survival rate of less than 5 percent and has seen few improvements in survival over the last three decades.
"We have mammograms to screen for breast cancer and colonoscopies for colon cancer but we have had nothing to help us screen for pancreatic cancer," says Nita Ahuja, M.D., an associate professor of surgery, oncology and urology at the Johns Hopkins University School of Medicine and leader of the study described online this month in the journal Clinical Cancer Research. "While far from perfect, we think we have found an early detection marker for pancreatic cancer that may allow us to locate and attack the disease at a much earlier stage than we usually do."
For their study, Ahuja and her colleagues were able to identify two genes, BNC1 and ADAMTS1, which together were detectable in 81 percent of blood samples from 42 people with early-stage pancreatic cancer, but not in patients without the disease or in patients with a history of pancreatitis, a risk factor for pancreatic cancer. By contrast, the commonly used PSA antigen test for prostate cancer only picks up about 20 percent of prostate cancers.
Ahuja and her colleagues found that in pancreatic cancer cells, it appears that chemical alterations to BNC1 and ADAMTS1 -- epigenetic modifications that alter the way the genes function without changing the underlying DNA sequence -- silence the genes and prevent them from making their protein product, the role of which is not well-understood. These alteration
|Contact: Stephanie Desmon|
Johns Hopkins Medicine