UNC researcher aims to 'unmask' cancer cells to trigger body's immune system

CHAPEL HILL — Cancer cells are deadly traitors, good cells gone bad. They evade the body's defense systems, passing themselves off as organisms that pose no threat.

But researchers at the University of North Carolina at Chapel Hill's Eshelman School of Pharmacy are working on a way to blow their cover.

Moo J. Cho, Ph.D., an associate professor of molecular pharmaceutics, is creating a delivery system that would embed bacterial elements in a cancer tumor in order to encourage the body's immune system to recognize and attack the tumor.

"It's like planting a big red flag on the tumor to attract the attention of the body's immune system, which normally ignores cancerous cells," Cho said. "It's a great idea. We just don't know how to do it yet."

To support his work, Cho, who is also a member of UNC's Lineberger Comprehensive Cancer Center, has received a five-year grant from the National Cancer Institute worth more than $1.5 million.

The goal of the research is to develop a unique way to intravenously administer a nucleic acid derived from bacteria and deliver it to a tumor. While it is possible to inject some tumors directly, many are relatively inaccessible and can be better reached through the body's own pathways, Cho said.

The bacteria's nucleic acid would normally be excreted very rapidly from the body when delivered via IV. Cho plans to add a molecule to the nucleic acid that will allow it to latch on to a class of proteins called IgG immunoglobulin that occur naturally in the body.

"We will ask the IgG antibodies to carry the bacteria-derived nucleic acid as a guest throughout the body," Cho said. "This will allow the nucleic acid to circulate for days, which is different from how antibodies have been used in classical targeted delivery."

Cho believes that eventually enough nucleic acid will be carried to the tumor to attract the attention of nearby immune cells, which recognize the nucleic acids as an invading pathogen, triggering an anti-tumor immune response. This approach differs from the classical method of actively targeting a tumor based on specific markers.