Injecting immune stimulants turns tumors into "cancer vaccine factories"
Scientists at New York's Icahn School of Medicine at Mount Sinai have made an exciting breakthrough in the realm of cancer treatment, describing a new way of supercharging the body's immune system so that it can take the upper hand and destroy tumor cells around the body.
The technique falls under an arm of cancer treatment known as immunotherapy. In essence, this means equipping the body's natural defenses with some extra weaponry so they can better take the fight to cancer. There are a few ways to go about this, including harvesting the immune system's T cells and engineering them to more effectively recognize the predatory cancer cells, known as adoptive immunotherapy, or treating T cells with drugs to disable proteins that would otherwise neutralize their attacks, known as checkpoint blockade immunotherapy.
In what they describe as a novel approach, the researchers at Mount Sinai tried to quell cancerous cells by injecting carefully chosen immune stimulants directly into the tumor site. One of these stimulants recruits immune cells called dendritic cells, which take on the role of general of the immune system army, while another instructs those dendritic cells to command the T cells to kill off the cancer cells.
These work together to train the immune system to better recognize a tumor cell when it sees one, and take a more active role in hunting them down throughout the body and killing them off. The researchers describe this as "in situ vaccination" and say that it effectively turns a tumor into a cancer vaccine factory.
It was first tested in the lab on mice where it greatly improved the effectiveness of checkpoint blockade immunotherapy. The team then tested it on 11 patients with advanced stage lymphoma as part of a clinical trial, where some experienced full remission for periods ranging from months to years.
Buoyed by these promising results, the researchers have already kicked off clinical trials for lymphoma, breast, head and neck cancer patients, and lab tests are continuing on liver and ovarian cancer. The team says that combining this in situ vaccine technique with checkpoint blockage immunotherapy is at least three times as powerful as either on their own, and they are "extremely optimistic" about the new trials.
"The in situ vaccine approach has broad implications for multiple types of cancer," says lead author Joshua Brody. "This method could also increase the success of other immunotherapies such as checkpoint blockade."
The research was published in the journal Nature Medicine.
Source: Mount Sinai