Researchers led by Ludwig MIT’s Sangeeta Bhatia devised a diagnostic nanoparticle that can reveal the presence of tumors through a urine test and double as an imaging agent, pinpointing where the tumors are located. Their work was reported in a July paper in Nature Materials. Sangeeta’s lab has for several years been developing diagnostic nanoparticles coated with peptides that are selectively cleaved by enzymes known as proteases, including matrix metalloproteases, which are specifically expressed by cancer cells as they shape their environment and metastasize. When the particles enter a tumor, the peptides are snipped off by the proteases and excreted in the urine, where they can be detected via fluorescence. But it’s one thing to detect a tumor, quite another to locate where it’s growing. To equip their nanodetectors with that capability, Sangeeta and her colleagues added to them a radioactive tracer, copper-64, and coated them with a peptide that favors acidic environments, which are common in tumors. The peptides insert themselves into cell membranes in such environments, generating a strong signal for PET imaging. The technology could prove useful for cancer diagnostics and monitoring of patients for cancer recurrence.
This article appeared in the February 2022 issue of Ludwig Link. Click here to download a PDF (1 MB).