Cancer treatments have come a long way from just chemotherapy and radiation. Researchers at Harvard University and the Dana-Farber Cancer Institute's Cancer Vaccine Center have announced the start of a Phase I clinical trial of an implantable treatment for the deadly skin cancer melanoma.
Melanoma causes 8,000 U.S. deaths a year, according to the Centers for Disease Control and Prevention (CDC).
The team took advantage of bio-inspired technology, and devised a treatment that will get patients' own immune systems to target cancerous cells.
Existing therapies use stem cells that have been removed from the patient and manipulated in a laboratory to stimulate an immune response, but sometimes, the body doesn’t accept the treatment. By implanting a vaccine that works in the body over time, it’s possible to cut out the laboratory middleman and decrease the risk of rejection.
“It was surprising that this technology, which manipulates immune cells in the body, was as effective or more than approaches in which the cells are manipulated in a laboratory and then infused into the individual,” says project lead David Mooney, a Robert P. Pinkas Family Professor of Bioengineering at Harvard.
Not to mention, the implant may also be cheaper. “Therapies that manipulate cells outside of the body are complex and expensive, and we desired to move the relevant biology into the body instead,” Mooney says.
The Body's White Knights
The implant works by stimulating dendritic cells (DCs), specific white bloods cells that are promising for immunotherapy because they regulate other white blood cells called T-cells. White blood cells are the body's warriors, used to fight off invading bacteria, viruses, and cancer cells. Researchers found that in mice, DCs spur an immune response against melanoma tumors.
In a preclinical study published in Science Translational Medicine in 2009, tiny sponges containing the white blood cell growth factor GM-CSF were inserted into the backs of seven-to-nine-week-old male mice to prompt a DC response. Half of the mice that received two doses of GM-CSF saw their tumors disappear completely. Now, it’s time to try this promising treatment on humans.
Not Your Average Implant
“This implant led to complete regression of a high percentage of tumors in mouse models of melanoma, and this was a significant improvement over previous therapeutic vaccines,” Mooney says.
Clinical trials will determine which patients will benefit the most from implanted vaccines, Mooney says.
Ideally, this implantable treatment, which recruits a person’s own immune cells to circulate throughout the body and target cancerous cells, could be used to treat a variety of cancers.
“We believe this approach may be useful for the treatment of a number of other types of cancer,” Mooney says. He and his team are currently exploring these possibilities.