Routine vaccinations have been part of our lives since childhood. It was always thought the vaccine only protected you from the specific pathogen for which you were getting vaccinated. However, a recent group at the University of Massachusetts Amherst found that these routine vaccinations might provide a protective benefit against cancer.
A research team led by Dr. Neil Forbes, Professor of Chemical Engineering, demonstrated that an antigen, from childhood vaccines can direct the immune system to fight cancer. An antigen is a protein in your body that elicits an immune response specifically to that antigen. Interestingly, Forbes and others found that these antigens can be delivered to the tumor and effectively suppress proliferation and recurrence. Researchers used a bacterial delivery system in which a non-toxic form of salmonella releases the vaccine antigen once it is inside a cancer cell. Much like a nanoparticle drug delivery system, this delivery system can also be used to release different drugs at the cellular level and is a unique method that improves specificity in drug treatment.
Forbes and others, who published the paper in Frontiers of Immunology, state that this immunotherapy has the potential to have broad effects in various cancer types. The Forbes Lab at the Institute for Applied Life Sciences (IALS) study different mechanisms of immunotherapy in multiple cancer models including liver, breast, and pancreatic. Currently the Forbes Lab is working to patent their delivery system and license it out to Ernst Pharmaceuticals, which is a start-up company co-founded by Forbes and the two co-first authors of the paper: Nele Van Dessel and Vishnu Raman. Interestingly, Van Dessel developed the delivery system while a postdoctoral fellow in the Forbes Lab. The goal of the Forbes Lab is to get U.S. Food and Drug Administration (FDA) approval and use the delivery system in clinical trials.
The concept behind the immunotherapy is to get vaccinated and then redirect the antigen to tumor cells that do not normally express antigen. This technology would trick the immune system in attacking the cancer because the antigen embedded in the cancer is from a separate pathogen. It is another way to make unresponsive cancers recognizable to the immune system. Normally, aggressive cancers remain invisible to the immune system because they do not express antigens. This delivery system specifically puts antigens in the cancer to elicit an immune response.
Forbes and others genetically modified salmonella to deliver antigen into mice with pancreatic tumors once injected with the antigen specific vaccine. The researchers found that the vaccine generated an immune response in which the cancer was attacked. The therapy cleared almost half of the pancreatic cancer, increased survival of mice, and prevented tumor recurrence. Specifically, in some mice the researchers found complete cure of pancreatic tumor. These results are significant because they indicate that mice are extremely responsive to therapy and have durable lasting immunity after immunization.
Forbes and colleagues generated a novel approach to treat cancer through routine vaccinations. By redirecting antigen release into tumors, the immune system is able to recognize tumor invasion and respond. This research has significant impacts to the field of immunotherapy. The delivery system used can provide treatment options in a broad range of cancers. More importantly, this technology has the potential to improve immunotherapy and quality of life in cancer patients.
University of Massachusetts Amherst, Neil Forbes, Nele Van Dessel, Vishnu Raman, Forbes Lab, IALS, FDA, paper, Frontiers of Immunology, Ernst Pharmaceuticals
