Biomarker found to detect pancreatic cancer much earlier than other techniques

Scientists have found a specific biomarker that could detect pancreatic cancer much earlier and simpler than current methods. This may allow surgical intervention at an earlier stage in a cancer population with an average 5-year survival rate of only 7.2%.

A team of scientists at the University of Texas MD Anderson Cancer Center in Houston found the biomarker—glypican-1 (GPC1)—on cancer exosomes. Exosomes are extracellular vesicles, containing nucleic acids and proteins, that are secreted by all cells and circulate in the blood.

The scientists isolated and monitored GPC1-enriched circulating exosomes, termed GPC1+ crExos, from the blood of pancreatic cancer patients.

“GPC1+ crExos were detected in small amounts of serum from about 250 patients with pancreatic cancer with absolute specificity and sensitivity, importantly distinguishing patients with chronic pancreatitis from those with early- and late-stage pancreatic cancer,” said lead investigator Raghu Kalluri, MD, PhD, chair of Cancer Biology at MD Anderson.

While pancreatic cancer represents only 3% of all new cancer cases in the United States, it’s the third leading cause of cancer death, according to the National Cancer Institute.

Patients with higher GPC1-positive levels were more likely to have precancerous pancreatic lesions. Thus, GPC1 appears to be a more reliable screening tool than the commonly used carbohydrate antigen 19-9 biomarker, which could not distinguish people with precancerous lesions from healthy controls, the researchers noted.

They also found that GPC1 predicted pancreatic cancer in mouse models before the mice showed signs of pancreatic disease by MRI or other techniques.

“Routine screening of the general population for pancreatic cancer using MRIs or CTs would be prohibitively expensive, with the likelihood for many false positives,” said David Piwnica-Worms, MD, PhD, chair of Cancer Systems Imaging at MD Anderson. “Our study suggests the potential for GPC1+ crExos as a detection and monitoring tool for pancreatic cancer in combination with imaging, with an emphasis on its application in early detection.”

If pancreatic cancer is detected early, surgery can be curative for patients. But because pancreatic cancer is often diagnosed in the later stages, only about 15% of patients qualify for the surgery.

“Studies comparing stage of disease with outcome following surgery suggest that death rates for pancreatic cancer would be reduced if the disease were diagnosed at an earlier stage,” Dr. Kalluri said. “This presents an unprecedented opportunity for informative early detection of pancreatic cancer and in designing potential curative surgical options.”