With La Jolla Institute of Immunology experts, a team from UC San Diego showed promise using immunity against a common virus as a cancer treatment.
UC San Diego researchers have discovered hope for a new treatment approach to pancreatic cancer in leveraging the body’s natural immune responses to cytomegalovirus (CMV), a common but typically harmless virus. Working with CMV experts at La Jolla Institute of Immunology, the team harnessed CMV immunity to significantly delay pancreatic tumor growth and extend survival in mice.
The scientists’ results, published Feb 4 in the Journal for ImmunoTherapy of Cancer, may mean a new direction for attacking pancreatic cancer, one of the deadliest and most treatment-resistant cancers, offering an effective and less expensive alternative to traditional immunotherapies.
In delivering small pieces of viral proteins, called CMV peptides, to pancreatic tumors directly via the bloodstream, the scientists redirected the virus-specific T cells against the cancer cells.
“We were thrilled to see such a strong response in our preclinical studies,” co-senior author Tatiana Hurtado de Mendoza, PhD, assistant professor of surgery at UCSD School of Medicine, said in a press release.
“Because our strategy relies only on previous immunity against CMV and not on the specific characteristics of an individual’s tumor, it has the potential to be an off-the-shelf solution that could be applicable to a large number of patients,” Hurtado de Mendoza continued.
Testing the CMV-immunity approach in mice, the researchers found treated mice gained a 70% increase in survival, living 42 days compared to 25 days for control mice.
The treatment also changed the gene expression profile of tumor cells, making them more sensitive to an immune response.
“This therapy represents a significant step forward in the fight against pancreatic cancer, and we’re hopeful that it could provide new treatment options for patients with limited alternatives,” said co-first author Jay Patel, a research assistant at UCSD.
The hope is necessary: pancreatic cancer, which accounts for 3.3% of all cancer cases but 8.4% of deaths, has a five-year survival rate of just 12%; current immunotherapies that are successful in melanoma or lung cancer patients have mostly failed in pancreatic cancer.
And the new approach might also be effective against a range of cancer types, as the researchers noticed its “potential to be tumor-agnostic,” Hurtado de Mendoza said. “We’re excited to explore its potential in humanized mouse models to bring it one step closer to clinical trials.”
“CMV-specific T cells have the potential to become a powerful tool in the fight against cancer,” Patel added. “We’re only just beginning to unlock their possibilities.”
