Scientists at the University of Illinois Chicago report they have developed an experimental anti-cancer peptide, dubbed aurB, based on a bacterial protein found in tumor samples and designed to disrupt cancer cells’ mitochondrial energy production.
Researchers at the University of Illinois Chicago (UIC) say they have created an experimental cancer treatment based on bacteria that naturally live inside tumors. The treatment is built from a small fragment of a bacterial protein—a peptide they call aurB—that they report can disrupt energy production in tumor cell mitochondria.
In preclinical work in prostate cancer, the team reported that aurB produced striking anti-tumor effects when combined with radiation therapy, a standard prostate cancer treatment. According to the researchers, the combination substantially reduced tumor growth in mouse models of hormone therapy-resistant prostate cancer and did so without signs of significant toxicity.
Tohru Yamada, the study’s senior author and an associate professor in UIC’s departments of surgery and biomedical engineering, said the group aimed to develop an approach that does not depend on the tumor-suppressor gene p53, which is frequently mutated in cancer.
“We wanted to have an anti-cancer agent that doesn't use the p53 function,” Yamada said.
Instead, the researchers reported that aurB acts by targeting mitochondria—often described as the cell’s “power plants.” In laboratory experiments, they found that aurB can enter tumor cell mitochondria and attach to ATP synthase, a protein essential for generating ATP, the cell’s main energy source.
For the study, the team analyzed tumor samples from breast cancer patients and used DNA sequencing to identify bacteria present inside the tumors. They focused on a bacterial species that contained a copper-containing cupredoxin protein called auracyanin, then designed aurB based on auracyanin.
UIC said it has patented aurB with support from the university’s Office of Technology Management, and the researchers are exploring paths to advance the therapy into human clinical trials. The findings were published in Signal Transduction and Targeted Therapy.