Researchers from the Penn State Materials Research Institute have developed a biodegradable and photoluminescent nanoparticle that are carried by immune cells to target melanoma. The team’s work was published last week in the journal Small. 

“The traditional way to deliver drugs to tumors is to put the drug inside some type of nanoparticle and inject those particles into the bloodstream,” co-senior author Jian Yang said in prepared remarks. “Because the particles are so small, if they happen to reach the tumor site they have a chance of penetrating through the blood vessel wall because the vasculature of tumors is usually leaky.”

A protein or antibody-coating on the outside of nanoparticles helps to bind the particle with a cancer cell. But this process is still passive – if the nanoparticle doesn’t interact with the tumor, they can’t bind to deliver the drug. The team hypothesized that immune cells could act as a means to actively target drugs to cancerous cells.

“I have 10 years of working in immunology and cancer,” co-senior author Cheng Dong said. “Jian is more a biomaterials scientist. He knows how to make the nanoparticles biodegradable. He knows how to modify the particles with surface chemistry, to decorate them with peptides or antibodies. His material is naturally fluorescent, so you can track the particles at the same time they are delivering the drug, a process called theranostics that combines therapy and diagnostics. On the other hand, I study the cancer microenvironment, and I have discovered that the microenvironment of the tumor generates kinds of inflammatory signals similar to what would happen if you had an infection.”

In their proof-of-concept study, the team targeted circulating melanoma cells and showed that immune cells could bind to the melanoma cells under conditions that mimicked those found in the bloodstream. Next, the team hopes to perform animal studies, since their initial experiments were performed outside the body.

“This is the first study and is just to show that the technology works,” Dong explained. “This study is not about curing melanoma. There are probably other ways to do that. We used melanoma cells to validate the approach.”