A diagnosis of pancreatic cancer usually isn’t a good one. Difficult to detect and quick to spread, the mortality rate for its most common form is a grim 93% after five years.

Which is why a team of researchers chose it as a testbed for their latest experimental treatment—one that involves using our body’s own intracellular messengers to precisely deliver a deadly payload.

The messengers, known as exosomes, are tiny packages that our cells produce and load up with proteins and RNA before releasing them into the bloodstream. There, they wind their way though the body until they reach their intended target. By adding an engineered strand of RNA to the payload, Valerie LeBleu, an assistant professor of cancer biology at the University of Texas MD Anderson Cancer Center, and her colleagues think they can halt even the most recalcitrant of tumors like late-stage pancreatic cancers.

Here’s Emily Mullin, reporting for Technology Review: