Many kinds of cells shed microvesicles, small pouches that pucker off cells’ outer membrane. For decades, researchers have ignored microvesicles, thinking of them as a kind of cellular debris. But in the last few years, scientists have discovered that microvesicles contain DNA and other molecules, and that they can be linked to the cell type from which they came. Cancer cells shed a lot of microvesicles. “So you would easily find a million to several billion tumor microvesicles per milliliter of blood,” says Ralph Weissleder, MD, PhD, who is a professor of radiology at Harvard Medical School.
Until now, finding cancer-related microvesicles required a complicated process that can take days. But at Massachusetts General Hospital’s Center for Systems Biology, where Dr. Weissleder is the director, he and his team have developed a handheld device that uses a nanotechnology sensor to detect tumor microvesicles in a drop of blood in about 2 hours. The technology has the potential to diagnose cancer early.
“It’s opening new frontiers in diagnostics that can save lives. We’re trying to figure out how useful it is for other cancers and diseases,” says Dr. Wissleder. Such a device could also be used to help determine how well a cancer treatment is working, because the device also measures the composition of microvesicles, which changes with cancer treatment.
(Source: Harvard Health Letter, February 2013, Harvard Health Publications)