Nanoparticles used for 'tumor painting'

Brain cancer is one of the most difficult-to-treat cancers; imaging is imperfect because brain cancer is so invasive, and its often difficult to tell where the diseases tissue ends and healthy tissue begins. Surgeons remove as much tumor tissue as possible, and then patients must endure chemo or radiation to kill the remaining cancerous cells.

University of Washington have developed fluorescent nanoparticles that could eventually be used to improved MRI images in patients afflicted with brain cancer. Injected into the bloodstreams of mice, the nanoparticles were able to safely cross the blood-brain barrier without damaging it. The result is greater contrast on the MRIs surgeons use during brain cancer tumor removal surgery. "If we can inject these nanoparticles with infrared dye, they will increase the contrast between the tumor tissue and the normal tissue," said lead study author Miqin Zhang said. "So during the surgery, the surgeons can see the boundary more precisely. We call it 'brain tumor illumination or brain tumor painting.'" She added, "The tumor will light up."

Before the team's work, no imaging nanoparticle had been able to cross the blood-brain barrier and specifically bind to brain tumor cells. UW researchers were able to engineer a nanoparticle that remained small enough to cross the barrier, and then used a peptide called chlorotoxin to target tumor cells.

The team will explore whether the nanoparticle can go beyond imaging to actually treat diseased tissue. Their next project will examine whether their nanoparticles can slow the spread of brain cancer.

- here's the report