PHILADELPHIA, Feb. 18 (UPI) -- Scientists have proven successful in engineering immune cells to track down and attack cancer cells. The heat-seeking T cells have proven effective in controlling brain tumor growth in mice, and have also shown promise as a potential treatment for two types of leukemia.
The new treatment technique is specific to cancers that express the protein EGFRvIII. Roughly a third of all glioblastomas -- the most common and aggressive type of brain tumor -- feature EGFRvIII. Tumors that express the protein tend to be the most aggressive and the most resistant to traditional treatments.
The unique treatment begins with the extraction of blood from the cancer patient. The sample's T cells, the body's main blood-bound immune cell, are isolated and trained to hunt down a specific protein via gene therapy.
The engineered T cells are then reintroduced to the patient. The cells seek out the tumor, binding to the surface of the EGFRvIII-expressing cells and inhibiting growth.
"A series of Penn trials that began in 2010 have found that engineered T cells have an effect in treating some blood cancers, but expanding this approach into solid tumors has posed challenges," lead study author Dr. Marcela Maus, an assistant professor of oncology at the University of Pennsylvania's Abramson Cancer Center, explained in a press release.
"A challenging aspect of applying engineered T cell technology is finding the best targets that are found on tumors but not normal tissues," Maus added. "This is the key to making this kind of T cell therapy both effective and safe."
While the cancer-hunting T cells weren't enough to thwart cancer alone, when mice with human brain tumors were treated simultaneously with chemotherapy and targeted T cell therapy, researchers were able to control the growth of the glioblastomas.
The treatment was safe and effective enough to move onto a Phase 2 trial, with human patients. Twelve people with EGFRvIII-expressing brain cancer have already begun the experimental treatment.
Researchers say a similar technique could allow scientists to engineer T cells to thwart leukemia, as well.
The new study was published this week in the journal Science Translational Medicine.