Scientists have developed a new blood test that could detect the signs of pancreatic cancer in less than an hour. Pancreatic cancer is tough to cure because it is usually not discovered until it has reached an advanced stage. The test, described in the journal ACS Nano, can rapidly screen a drop of blood for biomarkers of pancreatic cancer. It can provide results in less than an hour. “An important step towards being able to cure diseases that come out of nowhere, like pancreatic cancer, is early detection,” said Jean Lewis, an assistant project scientist at the University California, San Diego in the US.
“We envision that in the future, physicians might perform this type of test using a quick finger stick to diagnose patients who may not know they have the disease yet,” said Lewis. To screen for pancreatic cancer in the blood, researchers are developing new methods that involve collecting and analysing nano-sized biological structures called exosomes, which are released from all cells in the body, including cancer cells. Exosomes contain proteins and genetic material that can serve as biomarkers for detecting cancers. Since exosomes are so tiny and fragile, they are hard to isolate from blood. Current methods to extract exosomes are time-consuming and require that blood samples be pretreated or diluted prior to use, researchers said.
The new test uses an electronic chip-based system to extract exosomes directly from blood in minutes. “We can use just a drop of blood as is – no extra processing required,” said Lewis. “We can also analyse the exosomes right there on the spot and show whether they carry any of the cancer biomarkers we are looking for,” he said. The test is simple and involves applying a drop of blood on a small electronic chip, turning the current on, and waiting several minutes, after which fluorescent labels are added to look at the results under a microscope.
If a blood sample tests positive for pancreatic cancer, bright fluorescent circles will appear. “This test could be used as a primary screening strategy to identify patients who would subsequently need to undergo more expensive and invasive diagnostic methods like a CT scan, MRI or endoscopy,” said Rebekah White, an associate professor at University California, San Diego.