A new early detection tool uses an innovative strategy to analyze blood samples for a specific pancreatic cancer marker, or protein. The technology requires only a very small blood sample to detect tumor-derived extracellular vesicles (EVs), which he describes as “tiny bubbles of material emitted from most living cells.

The test detects tumor-derived EVs that carry a protein called Ephrin type-A receptor 2 (EphA2), which the researchers consider a distinct biomarker of pancreatic cancer. The group believes that rapid and inexpensive blood tests to detect this marker could potentially diagnose pancreatic cancer at its earliest stages.

With the diagnostic tool, blood samples are diluted and applied to a sensor chip. The chip is coated with antibodies of one EV protein. EVs that bind to the chip are mixed with antibody-coated nanoparticles — one green, one red — that recognize a second EV protein and the pancreatic cancer marker EphA2. Only pancreatic cancer EVs bind both nanoparticles, and this double-binding event produces a strong color change that is easily detectable when EV sensor chips are examined under a microscope.

The test could also inform cancer treatment progress, because EV levels should increase as tumor mass can increase or decrease in response to treatment. This is especially important for pancreatic cancer patients whose tumors often exhibit severe resistance to antitumor therapies.